AKAMAI TECHNOLOGIES, INC.,

                                     Issuer,

                                       and

                      STATE STREET BANK AND TRUST COMPANY,

                                     Trustee

                            ------------------------


                                    INDENTURE


                            Dated as of June 20, 2000

                            ------------------------



                                  $250,000,000

                 5-1/2% Convertible Subordinated Notes Due 2007


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                                TABLE OF CONTENTS
<TABLE>
<CAPTION>


<S>                                                                          <C>
ARTICLE I DEFINITIONS; TRUST INDENTURE ACT..................................   1
   SECTION 1.01. DEFINITIONS................................................   1
   SECTION 1.02. OTHER DEFINITIONS..........................................   5
   SECTION 1.03. INCORPORATION BY REFERENCE OF TRUST INDENTURE ACT..........   6
   SECTION 1.04. RULES OF CONSTRUCTION......................................   7

ARTICLE II THE NOTES........................................................   7
   SECTION 2.01. FORM AND DATING............................................   7
   SECTION 2.02. EXECUTION AND AUTHENTICATION...............................  11
   SECTION 2.03. REGISTRAR AND PAYING AGENT.................................  11
   SECTION 2.04. PAYING AGENT TO HOLD MONEY IN TRUST........................  12
   SECTION 2.05. HOLDER LISTS...............................................  12
   SECTION 2.06. TRANSFER AND EXCHANGE......................................  12
   SECTION 2.07. REPLACEMENT NOTES..........................................  17
   SECTION 2.08. OUTSTANDING NOTES..........................................  18
   SECTION 2.09. TREASURY NOTES.............................................  18
   SECTION 2.10. TEMPORARY NOTES; GLOBAL NOTES..............................  18
   SECTION 2.11. CANCELLATION...............................................  19
   SECTION 2.12. DEFAULTED INTEREST.........................................  19
   SECTION 2.13. CUSIP NUMBERS..............................................  19

ARTICLE III REDEMPTION......................................................  20
   SECTION 3.01. NOTICES TO TRUSTEE.........................................  20
   SECTION 3.02. SELECTION OF NOTES TO BE REDEEMED..........................  20
   SECTION 3.03. NOTICE OF REDEMPTION.......................................  20
   SECTION 3.04. EFFECT OF NOTICE OF REDEMPTION.............................  21
   SECTION 3.05. DEPOSIT OF REDEMPTION PRICE................................  21
   SECTION 3.06. NOTES REDEEMED IN PART.....................................  21
   SECTION 3.07. OPTIONAL REDEMPTION........................................  22
   SECTION 3.08. MANDATORY REDEMPTION.......................................  22
   SECTION 3.09. PURCHASE OFFER.............................................  22

ARTICLE IV COVENANTS........................................................  24
   SECTION 4.01. PAYMENT OF NOTES...........................................  24
   SECTION 4.02. REPORTS....................................................  24
   SECTION 4.03. COMPLIANCE CERTIFICATE.....................................  24
   SECTION 4.04. STAY, EXTENSION AND USURY LAWS.............................  25
   SECTION 4.05. CORPORATE EXISTENCE........................................  25
   SECTION 4.06. TAXES......................................................  26
   SECTION 4.07. FUNDAMENTAL CHANGE.........................................  26
   SECTION 4.08. LIMITATION ON STATUS AS INVESTMENT COMPANY.................  26
   SECTION 4.09. SPECIAL INTEREST...........................................  26
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<TABLE>
<CAPTION>

<S>                                                                          <C>
ARTICLE V CONVERSION........................................................  26
   SECTION 5.01. CONVERSION PRIVILEGE.......................................  26
   SECTION 5.02. CONVERSION PROCEDURE.......................................  27
   SECTION 5.03. FRACTIONAL SHARES..........................................  28
   SECTION 5.04. TAXES ON CONVERSION........................................  28
   SECTION 5.05. COMPANY TO PROVIDE STOCK...................................  28
   SECTION 5.06. ADJUSTMENT OF CONVERSION PRICE.............................  29
   SECTION 5.07. NO ADJUSTMENT..............................................  32
   SECTION 5.08. OTHER ADJUSTMENTS..........................................  32
   SECTION 5.09. ADJUSTMENTS FOR TAX PURPOSES...............................  32
   SECTION 5.10. NOTICE OF ADJUSTMENT.......................................  32
   SECTION 5.11. NOTICE OF CERTAIN TRANSACTIONS.............................  33
   SECTION 5.12. EFFECT OF RECLASSIFICATIONS, CONSOLIDATIONS,
                 MERGERS OR SALES ON CONVERSION PRIVILEGE ..................  33
   SECTION 5.13. TRUSTEE'S DISCLAIMER.......................................  34

ARTICLE VI SUBORDINATION....................................................  34
   SECTION 6.01. AGREEMENT TO SUBORDINATE AND RANKING.......................  34
   SECTION 6.02. NO PAYMENT ON NOTES IF SENIOR DEBT IN DEFAULT..............  35
   SECTION 6.03. DISTRIBUTION ON ACCELERATION OF NOTES; DISSOLUTION AND
                 REORGANIZATION; SUBROGATION OF NOTES ......................  36
   SECTION 6.04. RELIANCE BY SENIOR DEBT ON SUBORDINATION PROVISIONS........  38
   SECTION 6.05. NO WAIVER OF SUBORDINATION PROVISIONS......................  39
   SECTION 6.06. TRUSTEE'S RELATION TO SENIOR DEBT..........................  39
   SECTION 6.07. OTHER PROVISIONS SUBJECT HERETO............................  40

ARTICLE VII SUCCESSORS......................................................  40
   SECTION 7.01. LIMITATION ON MERGER, SALE OR CONSOLIDATION................  40
   SECTION 7.02. SUCCESSOR CORPORATION SUBSTITUTED..........................  41

ARTICLE VIII DEFAULTS AND REMEDIES..........................................  41
   SECTION 8.01. EVENTS OF DEFAULT..........................................  41
   SECTION 8.02. ACCELERATION...............................................  43
   SECTION 8.03. OTHER REMEDIES.............................................  43
   SECTION 8.04. WAIVER OF PAST DEFAULTS....................................  44
   SECTION 8.05. CONTROL BY MAJORITY........................................  44
   SECTION 8.06. LIMITATION ON SUITS........................................  44
   SECTION 8.07. RIGHTS OF HOLDERS TO RECEIVE PAYMENT.......................  45
   SECTION 8.08. COLLECTION SUIT BY TRUSTEE.................................  45
   SECTION 8.09. TRUSTEE MAY FILE PROOFS OF CLAIM...........................  45
   SECTION 8.10. PRIORITIES.................................................  45
   SECTION 8.11. UNDERTAKING FOR COSTS......................................  45

ARTICLE IX TRUSTEE..........................................................  46
   SECTION 9.01. DUTIES OF TRUSTEE..........................................  46
   SECTION 9.02. RIGHTS OF TRUSTEE..........................................  46
   SECTION 9.03. INDIVIDUAL RIGHTS OF TRUSTEE...............................  47
</TABLE>

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<TABLE>
<CAPTION>

<S>                                                                           <C>
   SECTION 9.04. TRUSTEE'S DISCLAIMER.......................................  47
   SECTION 9.05. NOTICE OF DEFAULTS.........................................  47
   SECTION 9.06. REPORTS BY TRUSTEE TO HOLDERS..............................  48
   SECTION 9.07. COMPENSATION AND INDEMNITY.................................  48
   SECTION 9.08. REPLACEMENT OF TRUSTEE.....................................  49
   SECTION 9.09. SUCCESSOR TRUSTEE BY MERGER, ETC...........................  50
   SECTION 9.10. ELIGIBILITY; DISQUALIFICATION..............................  50
   SECTION 9.11. PREFERENTIAL COLLECTION OF CLAIMS AGAINST COMPANY..........  50

ARTICLE X DISCHARGE OF INDENTURE............................................  50
   SECTION 10.01. TERMINATION OF COMPANY'S OBLIGATIONS......................  50
   SECTION 10.02. REPAYMENT TO COMPANY......................................  50

ARTICLE XI AMENDMENTS, SUPPLEMENTS AND WAIVERS..............................  50
   SECTION 11.01. WITHOUT CONSENT OF HOLDERS................................  50
   SECTION 11.02. WITH CONSENT OF HOLDERS...................................  51
   SECTION 11.03. COMPLIANCE WITH TRUST INDENTURE ACT.......................  52
   SECTION 11.04. REVOCATION AND EFFECT OF CONSENTS.........................  52
   SECTION 11.05. NOTATION ON OR EXCHANGE OF NOTES..........................  52
   SECTION 11.06. TRUSTEE PROTECTED.........................................  53

ARTICLE XII MISCELLANEOUS...................................................  53
   SECTION 12.01. TRUST INDENTURE ACT CONTROLS..............................  53
   SECTION 12.02. NOTICES...................................................  53
   SECTION 12.03. COMMUNICATION BY HOLDERS WITH OTHER HOLDERS...............  54
   SECTION 12.04. CERTIFICATE AND OPINION AS TO CONDITIONS PRECEDENT........  54
   SECTION 12.05. STATEMENTS REQUIRED IN CERTIFICATE OR OPINION.............  54
   SECTION 12.06. RULES BY TRUSTEE AND AGENTS...............................  54
   SECTION 12.07. LEGAL HOLIDAYS............................................  54
   SECTION 12.08. NO RECOURSE AGAINST OTHERS................................  55
   SECTION 12.09. COUNTERPARTS AND FACSIMILE SIGNATURES.....................  55
   SECTION 12.10. VARIABLE PROVISIONS.......................................  55
   SECTION 12.11. GOVERNING LAW, SUBMISSION TO JURISDICTION.................  56
   SECTION 12.12. NO ADVERSE INTERPRETATION OF OTHER AGREEMENTS.............  56
   SECTION 12.13. SUCCESSORS................................................  57
   SECTION 12.14. SEVERABILITY..............................................  57
   SECTION 12.15. TABLE OF CONTENTS, HEADINGS, ETC..........................  57

Exhibits
Exhibit A Form of Legends and Notes.........................................  A1

Exhibit B Form of Transfer Certificate for Transfer From Rule 144A Global
  Note or Restricted Note to Regulation S Global Note.......................  B1

Exhibit C Form of Transfer Certificate for Transfer From Regulation S Global
  Note or Restricted Note to Rule 144A Global Note..........................  C1

Exhibit D Form of Transfer Certificate for Transfer from Global Note or
  Restricted Note to Restricted Note........................................  D1

Exhibit E Form of Letter to be Delivered by Institutional Accredited
  Investors ................................................................  E1

</TABLE>

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                  INDENTURE, dated as of June 20, 2000, between Akamai
         Technologies, Inc., a Delaware corporation (the "COMPANY"), and State
         Street Bank and Trust Company, a Massachusetts Trust Company, as
         trustee (the "TRUSTEE").


                  Each party agrees as follows for the benefit of the other
         party and for the equal and ratable benefit of the Holders (as defined
         in Section 1.01 hereof) of the Company's 5-1/2% Convertible
         Subordinated Notes due 2007 (the "NOTES"):

                                   ARTICLE I
                        DEFINITIONS; TRUST INDENTURE ACT

SECTION 1.01 DEFINITIONS.


                  "AFFILIATE" of any specified Person means any other Person
         directly or indirectly controlling or controlled by or under direct or
         indirect common control with such specified Person. For purposes of
         this definition, "control" (including, with correlative meanings, the
         terms "controlling," "controlled by" and "under common control with"),
         as used with respect to any Person, shall mean the possession, directly
         or indirectly, of the power to direct or cause the direction of the
         management or policies of such Person, whether through the ownership of
         voting securities, by agreement or otherwise.


                  "AGENT" means any Registrar, Paying Agent, New York Presenting
         Agent or Conversion Agent.


                  "BOARD OF DIRECTORS" means the Board of Directors of the
         Company or any authorized committee of the Board of Directors.


                  "BOARD RESOLUTION" means a duly authorized resolution of the
         Board of Directors.


                  "BUSINESS DAY" means any day that is not a Legal Holiday.


                  "CAPITAL STOCK" means any and all shares, interests,
         participations, rights or other equivalents, however designated, of
         corporate stock, including, without limitation, partnership interests.


                  "COMMON STOCK" means the common stock, par value $0.01 per
         share, of the Company as the same exists at the date of the execution
         of this Indenture or as such stock may be constituted from time to
         time.

                  "COMPANY" means the party named as such above until a
         successor replaces it in accordance with Article VII and thereafter
         means the successor.


                  "DAILY MARKET PRICE" means the price of a share of Common
         Stock on the relevant date, determined (a) on the basis of the last
         reported sale price regular way of the Common Stock as reported on the
         Nasdaq Stock Market's National Market (the "NNM"), or if

                                       1
<PAGE>   6
         the Common Stock is not then listed on the NNM, as reported on such
         national securities exchange upon which the Common Stock is listed, or
         (b) if there is no such reported sale on the day in question, on the
         basis of the average of the closing bid and asked quotations regular
         way as so reported, or (c) if the Common Stock is not listed on the NNM
         or on any national securities exchange, on the basis of the average of
         the high bid and low asked quotations regular way on the day in
         question in the over-the-counter market as reported by the National
         Association of Securities Dealers Automated Quotation System, or if not
         so quoted, as reported by National Quotation Bureau, Incorporated, or a
         similar organization.


                  "DEFAULT" means any event that is, or with the passage of time
         or the giving of notice or both would be, an Event of Default.


                  "DEPOSITARY" shall mean The Depository Trust Company, its
         nominees and their respective successors.


                  "DESIGNATED SENIOR DEBT" means Senior Debt in which the
         instrument creating or evidencing the same or the assumption or
         guarantee thereof (or related agreements or documents to which the
         Company is a party) expressly provides that such Senior Debt shall be
         "Designated Senior Debt" for the purposes of the Indenture (provided
         that such instrument, agreement or other document may place limitations
         and conditions on the right of such Senior Debt to exercise the rights
         of Designated Senior Debt).


                  "EQUITY INTERESTS" means Capital Stock and all warrants,
         options or other rights to acquire Capital Stock, but excluding any
         Indebtedness that is convertible into, or exchangeable for, Capital
         Stock.


                  "EXCESS PAYMENT" means the excess of (A) the aggregate of the
         cash and value of other consideration paid by the Company or any of its
         Subsidiaries with respect to shares of the Company acquired in a tender
         offer or other negotiated transaction over (B) the market value of such
         acquired shares after giving effect to the completion of a tender offer
         or other negotiated transaction.


                  "EXCHANGE ACT" means the Securities Exchange Act of 1934, as
         amended.


                  "EXCHANGE RATE CONTRACT" means, with respect to any Person,
         any currency swap agreements, forward exchange rate agreements, foreign
         currency futures or options, exchange rate collar agreements, exchange
         rate insurance and other agreements or arrangements, or combination
         thereof, the principal purpose of which is to provide protection
         against fluctuations in currency exchange rates. An Exchange Rate
         Contract may also include an Interest Rate Agreement.


                  "FUNDAMENTAL CHANGE" means the occurrence of any transaction
         or event in connection with which all or substantially all of the
         Common Stock shall be exchanged for, converted into, acquired for or
         constitute in all material respects solely the right to receive
         consideration, whether by means of an exchange offer, liquidation,
         tender offer, consolidation, merger, combination, reclassification,
         recapitalization or otherwise, which is not all or substantially all
         common stock that is, or upon issuance will be, (i) listed on a United
         States national securities exchange, or (ii) approved for quotation on
         the NASDAQ

                                       2
<PAGE>   7

         National Market or any similar United States system of automated
         dissemination of quotations of securities prices.


                  "FUNDAMENTAL CHANGE OFFER" means a Purchase Offer.


                  "GAAP" means generally accepted accounting principles set
         forth in the opinions and pronouncements of the Accounting Principles
         Board of the American Institute of Certified Public Accountants and
         statements and pronouncements of the Financial Accounting Standards
         Board or in such other statements by such other entity as approved by a
         significant segment of the accounting profession, which are in effect
         on the Issuance Date and are applied on a consistent basis.


                  "GUARANTEE" means a guarantee, other than by endorsement of
         negotiable instruments for collection in the ordinary course of
         business, direct or indirect, in any manner, including, without
         limitation, letters of credit and reimbursement agreements in respect
         thereof, of all or any part of any Indebtedness.


                  "HOLDER" means a Person in whose name a Note is registered in
         the register referred to in Section 2.03.


                  "INDEBTEDNESS" means, with respect to any Person, any
         indebtedness of such Person, whether or not contingent, in respect of
         borrowed money or evidenced by bonds, notes, debentures or similar
         instruments or letters of credit, or reimbursement agreements in
         respect thereof, or representing the balance deferred and unpaid of the
         purchase price of any property (which purchase price is due more than
         six months after the placing into service or delivery of such property)
         including pursuant to capital leases and sale-and-leaseback
         transactions, or representing any hedging obligations under an Exchange
         Rate Contract or an Interest Rate Agreement, except any such balance
         that constitutes an accrued expense or trade payable, if and to the
         extent any of the foregoing indebtedness, other than obligations under
         an Exchange Rate Contract or an Interest Rate Agreement, would appear
         as a liability upon a balance sheet of such Person prepared in
         accordance with GAAP, and also includes, to the extent not otherwise
         included, the Guarantee of items which would be included within this
         definition if incurred directly by such Person. The amount of any
         Indebtedness outstanding as of any date shall be the accreted value
         thereof, in the case of any Indebtedness issued with original issue
         discount. Indebtedness shall not include liabilities for taxes of any
         kind.


                  "INDENTURE" means this Indenture, as amended from time to
         time.


                  "INITIAL PURCHASERS" means Donaldson, Lufkin & Jenrette
         Securities Corporation, Morgan Stanley & Co. Incorporated, Salomon
         Smith Barney Inc. and Thomas Weisel Partners LLC.


                  "INTEREST RATE AGREEMENT" means, with respect to any Person,
         any interest rate swap agreement, interest rate cap agreement, interest
         rate collar agreement or other similar agreement the principal purpose
         of which is to protect the party indicated therein against fluctuations
         in interest rates.

                                       3
<PAGE>   8
                  "ISSUANCE DATE" means the date on which the Notes are first
         authenticated and issued.


                  "NOTES" has the meaning set forth in the preamble hereto.


                  "OBLIGATIONS" means any principal, interest, penalties, fees,
         indemnifications, reimbursements, damages and other liabilities payable
         under the documentation governing any Indebtedness.


                  "OFFICER" means the Chairman of the Board, the President, any
         Vice President, the Treasurer, the Secretary, any Assistant Treasurer
         or any Assistant Secretary of the Company.


                  "OFFICERS' CERTIFICATE" means a certificate of the Company
         signed by two Officers, one of whom must be the Chairman of the Board,
         the President, the Treasurer or a Vice President of the Company.


                  "OPINION OF COUNSEL" means a written opinion from legal
         counsel who is reasonably acceptable to the Trustee. The counsel may be
         an employee of or counsel to the Company or the Trustee.


                  "PERSON" means any individual, corporation, partnership, joint
         venture, association, joint stock company, trust, unincorporated
         organization, limited liability company or government or any agency or
         political subdivision thereof.


                  "PURCHASE AGREEMENT" means the Purchase Agreement, dated as of
         June 15, 2000, among the Company and the Initial Purchasers.


                  "REGISTRATION DEFAULT" has the meaning set forth in Section 2
         of the Notes.


                  "REGISTRATION RIGHTS AGREEMENT" means the Registration Rights
         Agreement relating to the Notes and the underlying Common Stock, dated
         June 20, 2000, among the Company and the Initial Purchasers party
         thereto.


                  "SEC" means the Securities and Exchange Commission.


                  "SECURITIES ACT" means the Securities Act of 1933, as amended.


                  "SENIOR DEBT" means the principal of, interest on and other
         amounts due on (i) Indebtedness of the Company, whether outstanding on
         the date hereof or thereafter created, incurred, assumed or guaranteed
         by the Company, for money borrowed from banks or other financial
         institutions; (ii) Indebtedness of the Company, whether outstanding on
         the date hereof or thereafter created, incurred, assumed or guaranteed
         by the Company; and (iii) Indebtedness of the Company under interest
         rate swaps, caps or similar hedging agreements and foreign exchange
         contracts, currency swaps or similar agreements: unless, in the
         instrument creating or evidencing or pursuant to which Indebtedness
         under (i) or (ii) is outstanding, it is expressly provided that such
         Indebtedness is not senior in right of payment to the Notes. Senior
         Debt includes, with respect to the obligations described in clauses (i)
         and (ii) above, interest accruing, pursuant to the terms of such Senior
         Debt, on or after the filing of

                                       4
<PAGE>   9

         any petition in bankruptcy or for reorganization relating to the
         Company, whether or not post-filing interest is allowed in such
         proceeding, at the rate specified in the instrument governing the
         relevant obligation. Notwithstanding anything to the contrary in the
         foregoing, Senior Debt shall not include: (a) Indebtedness of or
         amounts owed by the Company for compensation to employees, or for goods
         or materials purchased in the ordinary course of business, or for
         services; and (b) Indebtedness of the Company to any Subsidiary of the
         Company.


                  "SHELF REGISTRATION STATEMENT" shall have the meaning set
         forth in the Registration Rights Agreement.


                  "SIGNIFICANT SUBSIDIARY" means any Subsidiary of the Company
         which is a "significant subsidiary" as defined in Rule 1-02(w) of
         Regulation S-X under the Securities Act and the Exchange Act, as such
         Regulation is in effect on the date hereof.


                  "SPECIAL INTEREST" has the meaning set forth in Section 2 of
         the Notes.


                  "SUBSIDIARY" means any corporation, association or other
         business entity of which more than 50% of the total voting power of
         shares of Capital Stock entitled, without regard to the occurrence of
         any contingency, to vote in the election of directors, managers or
         trustees thereof is at the time owned or controlled, directly or
         indirectly, by any Person or one or more of the other Subsidiaries of
         that Person or a combination thereof.


                  "TIA" means the Trust Indenture Act of 1939 (15 U.S. Code
         Sections 77aaa-77bbbb) as in effect on the date of execution of this
         Indenture.


                  "TRUSTEE" means the party named as such above until a
         successor replaces it in accordance with the applicable provisions of
         this Indenture and thereafter means the successor.


                  "TRUST OFFICER" means any officer or assistant officer of the
         Trustee assigned by the Trustee to administer its corporate trust
         matters.


                  "WHOLLY-OWNED SUBSIDIARY" of any specified Person means a
         Subsidiary of such Person all of the outstanding Capital Stock or other
         ownership interests of which (other than directors' qualifying shares)
         shall at the time be owned by such Person or by one or more
         Wholly-Owned Subsidiaries of such Person and one or more Wholly-Owned
         Subsidiaries of such Person.

SECTION 1.02.     OTHER DEFINITIONS.

<TABLE>
<CAPTION>

                                                                             DEFINED
  TERM                                                                       IN SECTION

<S>                                                                              <C>
"AGENT MEMBER".................................................................  2.01
"BANKRUPTCY LAW"...............................................................  8.01
"CLEARSTREAM"..................................................................  2.01
</TABLE>

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<TABLE>
<CAPTION>

<S>                                                                             <C>
"COMMENCEMENT DATE"............................................................  3.09
"CONVERSION AGENT".............................................................  2.03
"CONVERSION DATE"..............................................................  5.02
"CONVERSION PRICE".............................................................  5.01
"CONVERSION SHARES"............................................................  5.06
"CUSTODIAN"....................................................................  8.01
"DISTRIBUTION DATE"............................................................  5.06
"DISTRIBUTION RECORD DATE".....................................................  5.06
"EUROCLEAR"....................................................................  2.01
"EVENT OF DEFAULT".............................................................  8.01
"FUNDAMENTAL CHANGE  PAYMENT"..................................................  4.07
"GLOBAL NOTE"..................................................................  2.01
"GLOBAL NOTES LEGEND"..........................................................  2.01
"LEGAL HOLIDAY"................................................................ 12.08
"NEW YORK PRESENTING AGENT"....................................................  2.03
"OFFER AMOUNT".................................................................  3.09
"PAYING AGENT".................................................................  2.03
"PAYMENT BLOCKAGE NOTICE"......................................................  6.02
"PAYMENT BLOCKAGE PERIOD"......................................................  6.02
"PAYMENT DEFAULT"..............................................................  8.01
"PURCHASE DATE"................................................................  3.09
"PURCHASE OFFER"...............................................................  3.09
"QIBs".........................................................................  2.01
"REGULATION S" ................................................................  2.01
"REGULATION S GLOBAL NOTE".....................................................  2.01
"REGISTRAR"....................................................................  2.03
"RESTRICTED NOTES".............................................................  2.01
"RESTRICTED NOTES LEGEND"......................................................  2.01
"RIGHTS".......................................................................  5.06
"RULE 144A"....................................................................  2.01
"RULE 144A GLOBAL NOTE"........................................................  2.01
"TENDER PERIOD"................................................................  3.09
</TABLE>
SECTION 1.03.     INCORPORATION BY REFERENCE OF TRUST INDENTURE ACT.


                  Whenever this Indenture refers to a provision of the TIA, the
         provision is incorporated by reference in and made a part of this
         Indenture.


         The following TIA terms used in this Indenture have the following
         meanings:


                  "INDENTURE SECURITIES" means the Notes;


                  "INDENTURE SECURITY HOLDER" means a Holder of a Note;


                  "INDENTURE TO BE QUALIFIED" means this Indenture;

                                       6
<PAGE>   11


                  "INDENTURE TRUSTEE" or "INSTITUTIONAL TRUSTEE" means the
                  Trustee;
and


                  "OBLIGOR" on the Notes means the Company or any other obligor
                  on the Notes.


                  All other terms used in this Indenture that are defined by the
         TIA, defined by TIA reference to another statute or defined by SEC rule
         under the TIA have the meanings so assigned to them.

SECTION 1.04.     RULES OF CONSTRUCTION.

         Unless the context otherwise requires:

         (a)      a term has the meaning assigned to it;

         (b)      an accounting term not otherwise defined has the meaning
                  assigned to it in accordance with GAAP consistently applied;

         (c)      "OR" is not exclusive;

         (d)      words in the singular include the plural, and in the plural
                  include the singular;

         (e)      provisions apply to successive events and transactions;

         (f)      references to sections of or rules under the Securities Act
                  shall be deemed to include substitute, replacement or
                  successor sections or rules adopted by the SEC from time to
                  time; and

         (g)      a reference to "$" or U.S. Dollars is to United States
                  dollars.

                                   ARTICLE II
                                    THE NOTES

SECTION 2.01.     FORM AND DATING.


(a)      GENERAL.


                  The Notes and the Trustee's certificate of authentication
         shall be substantially in the form of Exhibit A hereto, which is hereby
         incorporated by reference and expressly made a part of this Indenture.
         The Notes may have notations, legends or endorsements required by law,
         stock exchange rule, agreements to which the Company is subject, if
         any, or usage (provided that any such notation, legend or endorsement
         is in a form acceptable to the Company). The Company shall furnish any
         such legend not contained in Exhibit A to the Trustee in writing. Each
         Note shall be dated the date of its authentication. The Notes shall be
         in denominations of $1,000 and integral multiples thereof. The terms
         and provisions of the Notes set forth in Exhibit A are part of this
         Indenture and to the extent applicable, the Company and the Trustee, by
         their execution and delivery of this Indenture, expressly agree to such
         terms and provisions and to be bound thereby. However, to the extent
         any provision

                                       7
<PAGE>   12

         of any Note conflicts with the express provisions of this Indenture,
         the provisions of this Indenture shall govern and be controlling.

                  (b) GLOBAL NOTES.


                  The Notes are being offered and sold by the Company pursuant
         to the Purchase Agreement. The Notes shall be offered and sold
         primarily to Qualified Institutional Buyers ("QIBs") in reliance on
         Rule 144A under the Securities Act ("RULE 144A"), as provided in the
         Purchase Agreement. The Notes shall be issued initially in the form of
         one or more permanent Global Notes in definitive, fully registered form
         without interest coupons with the Global Notes Legend ("GLOBAL NOTES
         LEGEND") and Restricted Notes Legend ("RESTRICTED NOTES LEGEND") set
         forth in Exhibit A hereto ("RULE 144A GLOBAL NOTE"), which shall be
         deposited on behalf of the purchasers of the Notes represented thereby
         with the Trustee, as custodian for the Depositary, and registered in
         the name of the Depositary or a nominee of the Depositary, duly
         executed by the Company and authenticated by the Trustee as hereinafter
         provided. The aggregate principal amount of the Rule 144A Global Note
         may from time to time be increased or decreased by adjustments made on
         the records of the Trustee and the Depositary or its nominee as
         hereinafter provided.


                  Notes transferred in reliance on Regulation S under the
         Securities Act ("REGULATION S") as provided in Section 2.06(a)(ii) and
         (v) hereof, shall be issued in the form of one or more permanent Global
         Notes in definitive, fully registered form without interest coupons
         with the Global Notes Legend and Restricted Notes Legend set forth in
         Exhibit A hereto (the "REGULATION S GLOBAL NOTE"), which shall be
         deposited on behalf of the transferees of the Notes represented thereby
         with the Trustee, as custodian, for the Depositary, and registered in
         the name of the Depositary or the nominee of the Depositary for the
         accounts of designated agents holding on behalf of the Euroclear System
         ("EUROCLEAR") or Clearstream Banking ("CLEARSTREAM"), duly executed by
         the Company and authenticated by the Trustee as hereinafter provided.
         The aggregate principal of the Regulation S Global Note may from time
         to time be increased or decreased by adjustments made on the records of
         the Trustee and the Depositary or its nominee as hereinafter provided.


                  So long as any Global Note is outstanding, owners of
         beneficial interests therein may transfer their interests therein only
         in reliance on Regulation S or to QIBs in reliance on Rule 144A in
         accordance with Section 2.06.

                  (c) BOOK-ENTRY PROVISIONS.


                  This Section 2.01(c) shall apply only to the Rule 144A Global
         Note and the Regulation S Global Note issued in the form of one or more
         permanent Global Notes (collectively, the "GLOBAL NOTES") deposited
         with or on behalf of the Depositary.


                  The Company shall execute and the Trustee shall, in accordance
         with this Section 2.01(c), authenticate and deliver initially one or
         more Global Notes that (a) shall be registered in the name of the
         Depositary for such Global Note or Global Notes or the nominee

                                       8
<PAGE>   13

         of such Depositary and (b) shall be delivered by the Trustee to such
         Depositary or pursuant to such Depositary's instructions or held by the
         Trustee as custodian for the Depositary.


                  Members of, or participants in, the Depositary ("AGENT
         MEMBERS") shall have no rights under this Indenture with respect to any
         Global Note held on their behalf by the Depositary or by the Trustee as
         the custodian of the Depositary or under such Global Note, and the
         Depositary may be treated by the Company, the Trustee and any agent of
         the Company or the Trustee as the absolute owner of such Global Note
         for all purposes whatsoever. Notwithstanding the foregoing, nothing
         herein shall prevent the Company, the Trustee or any agent of the
         Company or the Trustee from giving effect to any written certification,
         proxy or other authorization furnished by the Depositary or impair, as
         between the Depositary and its Agent Members, the operation of
         customary practices of such Depositary governing the exercise of the
         rights of an owner of a beneficial interest in any Global Note.

                  (d) CERTIFICATED NOTES.


                  So long as the Depositary or its nominee is the registered
         owner of a Note, the Depositary or such nominee, as the case may be,
         will be considered the sole owner or Holder of the Notes represented by
         the Global Notes for all purposes under the Indenture. Except as
         provided below, owners of beneficial interests in a Global Note will
         not be entitled to have Notes represented by such Global Note
         registered in their names, will not receive or be entitled to receive
         physical delivery of certificated Notes, and will not be considered the
         owners or holders thereof under the Indenture for any purpose,
         including with respect to the giving of any directions, instructions or
         approvals to the Trustee thereunder.


                  Other than as set forth below in this Section, certificated
         Notes will be issued to owners of beneficial interests in Global Notes
         in exchange for their interests in Global Notes only if (1) the Company
         notifies the Trustee in writing that the Depositary is no longer
         willing or able to act as a depositary and the Company is unable to
         locate a qualified successor within 90 days, or (2) the Company, at its
         option, notifies the Trustee in writing that it elects to cause the
         issuance of Notes in definitive form under the Indenture. In either
         case, upon surrender by the Depositary of the Global Notes,
         certificated Notes will be issued to each Person that the Depositary
         identifies as the beneficial owner of the Notes represented by the
         Global Notes. In addition, the Company will issue certificated Notes in
         exchange for interests in Global Notes upon the request of an owner of
         such an interest if an Event of Default has occurred and is continuing,
         in which case, upon receipt of such request and necessary information
         from the Depositary in accordance with its procedures, the principal
         Registrar shall instruct the Depositary as to the corresponding
         reduction to be made in the principal amount of the relevant Global
         Note. Finally, at such time as all Global Notes cease to be outstanding
         pursuant to clause (1) or (2) above, certificated Notes may be issued
         in accordance with paragraphs (vi) and (vii) of Section 2.06(a). Upon
         any such issuance, the Trustee shall register such certificated Notes
         in the name of such Person or Persons (or the nominee of any thereof),
         and cause the same to be delivered thereto. All such certificated Notes
         shall bear the Restricted Notes Legend set forth in Exhibit A hereto
         (collectively with the Accredited Investor Restricted Notes defined
         below, the "RESTRICTED NOTES") unless otherwise provided in this
         Section 2.01(d) and Section 2.06(b) hereof.


                                       9
<PAGE>   14

                  Notes offered and sold to "accredited investors" (as defined
         in Rule 501(a)(1), (2), (3) or (7) of Regulation D under the Securities
         Act), as provided in the Purchase Agreement, shall be issued in the
         form of one or more certificated Notes (subject to a minimum initial
         purchase amount of $100,000) in definitive, fully registered form
         without interest coupons with the Restricted Notes Legend set forth in
         Exhibit A hereto ("ACCREDITED INVESTOR RESTRICTED NOTES"), which shall
         be registered in the name of such Accredited Investor or its nominee,
         duly executed by the Company and authenticated by the Trustee as
         hereinafter provided. So long as Global Notes have not ceased to be
         outstanding pursuant to clause (1) or (2) in the immediately preceding
         paragraph above (and unless such Accredited Investor Restricted Notes
         have been exchanged for certificated Notes without a Restricted Notes
         Legend pursuant to the last paragraph in this Section, if applicable),
         such Accredited Investor Restricted Notes may only be transferred in
         reliance on Regulation S (pursuant to Section 2.06(a)(iv))or to QIBs in
         reliance on Rule 144A (pursuant to Section 2.06(a)(v)). After such time
         as Global Notes have ceased to be outstanding pursuant to clauses (1)
         or (2) in the immediately preceding paragraph, Accredited Investor
         Restricted Notes may be transferred to transferees who hold the
         transferred interests in the form of certificated Notes in accordance
         with Section 2.06(a)(vii) or Section 2.06(b).


                  Notwithstanding the foregoing, Notes offered and sold on the
         Issuance Date to "accredited investors" (as defined above) shall be
         issued initially in the form of one or more permanent Global Notes in
         definitive, fully registered form without interest coupons with the
         Global Notes Legend and Restrictive Notes Legend set forth in Exhibit A
         (the "Accredited Investor Global Note"), which shall be deposited on
         behalf of the purchasers of the Notes represented thereby with the
         Trustee, as custodian for the Depositary, and registered in the name of
         the Depositary or a nominee of the Depositary, duly executed by the
         Company and authenticated by the Trustee as hereinafter provided. Such
         Accredited Investor Global Note shall be deemed to be a Global Note for
         all purposes of this Indenture. Promptly after the Issuance Date, the
         Company shall cause the purchasers of the Accredited Investor Global
         Note to arrange with the Depositary for the exchange of such Accredited
         Investor Global Note for Accredited Investor Restricted Notes. Upon
         receipt by the principal Registrar of instructions from the Depositary
         directing the principal Registrar to authenticate and deliver one or
         more Accredited Investor Restricted Notes of the same aggregate
         principal amount as the beneficial interest in the Accredited Investor
         Global Note to be exchanged, such instructions to contain the name or
         names of the Holder or Holders of such Accredited Investor Restricted
         Note or Notes, the authorized denominations of the Accredited Investor
         Restricted Note or Notes to be so issued and appropriate delivery
         instructions, the principal Registrar will instruct the Depositary to
         reduce the Accredited Investor Global Note by the aggregate principal
         amount of the beneficial interest therein to be exchanged and to debit
         from the account of the Person making such exchange the beneficial
         interest in the Accredited Investor Global Note that is being
         exchanged, and concurrently with such reduction and debit the Company
         shall execute, and the Trustee shall authenticate and deliver, one or
         more Accredited Investor Restricted Notes of the same aggregate
         principal amount in accordance with the instructions referred to above.
         Certificated Notes may be issued as aforesaid notwithstanding any other
         provision of this Indenture to the contrary restricting the issuance of
         certificated Notes.




                                       10
<PAGE>   15
                  After a transfer of any Notes during the period of the
         effectiveness of a Shelf Registration Statement with respect to the
         Notes and pursuant thereto, all requirements for Restricted Notes
         Legends on such Notes will cease to apply; and, in this case a
         certificated Note without a Restricted Notes Legend will be available
         to the Holder of such Restricted Notes upon request (and surrender of
         such Note bearing the Restricted Notes Legend for cancellation). The
         Company shall give written notice to the Trustee, in the form of an
         Officer's Certificate, of the effectiveness of the Shelf Registration
         Statement, on which the Trustee and Registrant may rely.

SECTION 2.02.     EXECUTION AND AUTHENTICATION.


                  One Officer shall sign the Notes for the Company by manual or
         facsimile signature.


                  If an Officer whose signature is on a Note no longer holds
         that office at the time the Note is authenticated, the Note shall
         nevertheless be valid.


                  A Note shall not be valid until authenticated by the manual
         signature of an authorized officer of the Trustee. The signature shall
         be conclusive evidence that the Note has been authenticated under this
         Indenture.


                  The Trustee shall, upon a written order of the Company signed
         by an Officer, authenticate one or more Notes for original issue up to
         an aggregate principal amount stated in Section 6 of the Notes. The
         aggregate principal amount of Notes outstanding at any time may not
         exceed $300,000,000 except as provided in Section 2.07; provided that
         Notes in excess of $250,000,000 shall not be issued other than pursuant
         to the over-allotment option granted by the Company to the Initial
         Purchasers as provided in the Purchase Agreement. In the event thereof,
         the Company shall certify to the Trustee in an Officer's Certificate
         that such issuance is pursuant to such over-allotment option granted by
         the Initial Purchasers under the Purchase Agreement.


                  The Trustee may appoint an authenticating agent acceptable to
         the Company to authenticate Notes. An authenticating agent may
         authenticate Notes whenever the Trustee may do so. Each reference in
         this Indenture to authentication by the Trustee includes authentication
         by such agent. An authenticating agent has the same rights as an Agent
         to deal with Holders, the Company or an Affiliate.

SECTION 2.03.     REGISTRAR AND PAYING AGENT.


                  The Company shall maintain in the Borough of Manhattan, City
         of New York, State of New York, an office or agency where the Notes may
         be presented for registration of transfer or for exchange, payment and
         conversion (collectively, the "NEW YORK PRESENTING AGENT"). The Company
         initially designates STATE STREET BANK AND TRUST COMPANY, N.A., an
         affiliate of the Trustee, at its corporate trust offices in the Borough
         of Manhattan, City of New York, State of New York to act as New York
         Presenting Agent. The Trustee is initially appointed to act as Note
         registrar to maintain a register of transfers of the Notes (the "NOTE
         REGISTRAR") and to act as paying agent with respect to the Notes
         ("PAYING AGENT") and to act as agent for conversion of the Notes
         ("CONVERSION AGENT"). The Registrar shall keep a register of the Notes
         and of their transfer and exchange. The Company may

                                       11
<PAGE>   16
         appoint one or more co-Registrars, one or more additional Paying Agents
         and one or more additional Conversion Agents in such other locations as
         it shall determine. The term "Registrar" includes any co-Registrar, the
         term "Paying Agent" includes any additional Paying Agent and the term
         "Conversion Agent" includes any additional conversion agent. The
         Company may change any Paying Agent, Registrar, New York Presenting
         Agent or Conversion Agent without prior notice to any Holder. The
         Company shall notify the Trustee of the name and address of any Agent
         not a party to this Indenture. If the Company fails to appoint or
         maintain another entity as Registrar, Paying Agent, New York Presenting
         Agent or Conversion Agent, the Trustee shall act as such. The Company
         or any of its Affiliates may act as Paying Agent, Registrar, New York
         Presenting Agent or Conversion Agent.

SECTION 2.04.     PAYING AGENT TO HOLD MONEY IN TRUST.


                  The Company shall require each Paying Agent other than the
         Trustee to agree in writing that the Paying Agent will hold in trust
         for the benefit of Holders or the Trustee all money held by the Paying
         Agent for the payment of principal or interest on the Notes, and will
         notify the Trustee of any default by the Company in making any such
         payment. While any such default continues, the Trustee may require a
         Paying Agent to pay all money held by it to the Trustee and to account
         for any money disbursed by it. The Company at any time may require a
         Paying Agent to pay all money held by it to the Trustee. Upon payment
         over to the Trustee, the Paying Agent (if other than the Company or an
         Affiliate of the Company) shall have no further liability for the
         money. If the Company or an Affiliate of the Company acts as Paying
         Agent, it shall segregate and hold in a separate trust fund for the
         benefit of the Holders all money held by it as Paying Agent.

SECTION 2.05.       HOLDER LISTS.


                  The Trustee shall preserve in as current a form as is
         reasonably practicable the most recent list available to it of the
         names and addresses of Holders. If the Trustee is not the Registrar,
         the Company shall furnish to the Trustee on or before each interest
         payment date and at such other times as the Trustee may request in
         writing a list in such form and as of such date as the Trustee may
         reasonably require of the names and addresses of Holders.

SECTION 2.06.     TRANSFER AND EXCHANGE.


                  Whenever Notes are presented to the Registrar or a
         co-Registrar with a request to register a transfer or to exchange them
         for an equal principal amount of Notes of other denominations, the
         Registrar shall register the transfer or make the exchange if its
         requirements for such transactions are met. To permit registrations of
         transfers and exchanges, the Company shall issue and the Trustee shall
         authenticate Notes at the Registrar's request. No service charge shall
         be made to a Holder for any registration of transfer or exchange
         (except as otherwise expressly permitted herein), but the Company may
         require payment of a sum sufficient to cover any transfer tax or
         similar governmental charge payable in connection therewith (other than
         any such transfer tax or similar governmental charge payable upon
         exchanges pursuant to Sections 2.10, 3.06 or 11.05 hereof).

                                       12
<PAGE>   17
                  The Company shall not be required (i) to issue, register the
         transfer of or exchange any Note for a period beginning at the opening
         of business 15 days before the day of any selection of Notes to be
         redeemed under Section 3.02 hereof and ending at the close of business
         on the day of selection, or (ii) to register the transfer, or exchange,
         of any Note so selected for redemption in whole or in part, except the
         unredeemed portion of any Note being redeemed in part.

                  (a) Notwithstanding any provision to the contrary herein, so
         long as a Global Note remains outstanding and is held by or on behalf
         of the Depositary, transfers of a Global Note, in whole or in part, or
         of any beneficial interest therein, shall only be made in reliance on
         Regulation S or to QIBs in reliance on Rule 144A in accordance with
         Section 2.01(b), Section 2.01(d), Section 2.06(a) and Section 2.06(b);
         provided, however, that beneficial interests in a Global Note may be
         transferred to Persons who take delivery thereof in the form of a
         beneficial interest in the same Global Note in accordance with the
         transfer restrictions set forth in the Restricted Notes Legend and
         under the heading "Notice to Investors" in the Company's Offering
         Memorandum dated June 15, 2000.

                          (i) Transfer of Global Note to Depositary. Except for
                       transfers or exchanges made in accordance with clauses
                       (ii) through (vii) of this Section 2.06(a), transfers of
                       a Global Note shall be limited to transfers of such
                       Global Note in whole, but not in part, to nominees of the
                       Depositary or to a successor of the Depositary or such
                       successor's nominee.

                          (ii) Rule 144A Global Note To Regulation S Global
                       Note. If an owner of a beneficial interest in the Rule
                       144A Global Note deposited with the Depositary or the
                       Trustee as custodian for the Depositary wishes at any
                       time to transfer its interest in such Rule 144A Global
                       Note in reliance on Regulation S to a Person whose
                       purchase or acceptance thereof would not qualify as a
                       transaction exempt from registration requirements under
                       144A, such owner may, subject to the rules and procedures
                       of the Depositary, exchange or cause the exchange of such
                       interest for an equivalent beneficial interest in the
                       Regulation S Global Note. Upon receipt by the principal
                       Registrar of (1) instructions given in accordance with
                       the Depositary's procedures from an Agent Member
                       directing the principal Registrar to credit or cause to
                       be credited a beneficial interest in the Regulation S
                       Global Note in an amount equal to the beneficial interest
                       in the Rule 144A Global Note to be exchanged, (2) a
                       written (or electronic) order given in accordance with
                       the Depositary's procedures containing information
                       regarding the participant account of the Depositary (and
                       which may include the Euroclear or Clearstream account)
                       to be credited with such increase and (3) a certificate
                       in the form of Exhibit B attached hereto given by the
                       holder of such account interest, then the principal
                       Registrar shall instruct the Depositary to reduce or
                       cause to be reduced the principal amount of the Rule 144A
                       Global Note and to increase or cause to be increased the
                       principal amount of the Regulation S Global Note by the
                       aggregate principal amount of the beneficial interest in
                       the Rule 144A Global Note equal to the beneficial
                       interest in the Regulation S Global Note to be exchanged
                       or transferred and to debit or cause to be debited from
                       the account of the Person making such exchange or
                       transfer the beneficial interest in the Rule 144A Global
                       Note that is being exchanged or transferred.


                                       13
<PAGE>   18

                          (iii) Regulation S Global Note To Rule 144A Global
                       Note. If an owner of a beneficial interest in the
                       Regulation S Global Note deposited with the Depositary or
                       with the Trustee as custodian for the Depositary wishes
                       at any time to transfer its interest in such Regulation S
                       Global Note in reliance on Rule 144A to a Person whose
                       purchase or acceptance thereof would not qualify as a
                       transaction exempt from registration requirements under
                       Regulation S, such Holder may, subject to the rules and
                       procedures of Euroclear or Clearstream, as the case may
                       be, and the Depositary, exchange or cause the exchange of
                       such interest for an equivalent beneficial interest in
                       the Rule 144A Global Note. Upon receipt by the principal
                       Registrar of (1) instructions from the Depositary
                       directing the principal Registrar to credit or cause to
                       be credited a beneficial interest in the Rule 144A Global
                       Note equal to the beneficial interest in the Regulation S
                       Global Note to be exchanged or transferred, (2) a written
                       (or electronic) order given in accordance with the
                       Depositary's procedures containing information regarding
                       the participant account of the Depositary to be credited
                       and (3) a certificate in the form of Exhibit C attached
                       hereto given by the owner of such account interest then
                       the principal Registrar will instruct the Depositary to
                       reduce or cause to be reduced the Regulation S Global
                       Note and to increase or cause to be increased the
                       principal amount of the Rule 144A Global Note by the
                       aggregate principal amount of the beneficial interest in
                       the Regulation S Global Note to be exchanged or
                       transferred.


                          (iv) Accredited Investor Restricted Note or Other
                       Restricted Note to Rule 144A Global Note. If an owner of
                       an Accredited Investor Restricted Note or Other
                       Restricted Note registered in the name of such owner
                       wishes at any time to transfer such Restricted Note to a
                       Person in reliance on Rule 144A, such Holder may, subject
                       to the rules and procedures of the Depositary, exchange
                       or cause the exchange of such Restricted Note for an
                       equivalent beneficial interest in the Rule 144A Global
                       Note. Upon receipt by the principal Registrar of (1)
                       surrender of the Restricted Note to be transferred or
                       exchanged, (2) instructions from the Company, directing
                       the principal Registrar (A) to credit or cause to be
                       credited a beneficial interest in the Rule 144A Global
                       Note equal to the principal amount of the Restricted Note
                       to be exchanged or transferred and (B) to cancel such
                       Restricted Note to be exchanged or transferred, (3) a
                       written (or electronic) order given in accordance with
                       the Depositary's procedures containing information
                       regarding the participant account of the Depositary to be
                       credited and (4) a certificate in the form of Exhibit C
                       attached hereto given by the Holder of such Restricted
                       Note, then the principal Registrar will instruct the
                       Trustee to cancel such Restricted Note and will instruct
                       the Depositary to increase or cause to be increased the
                       principal amount of the Rule 144A Global Note by the
                       principal amount of the Restricted Note to be exchanged
                       or transferred.


                          (v) Accredited Investor Restricted or Other Restricted
                       Note To Regulation S Global Note. If an owner of a
                       Restricted Note registered in the name of such owner
                       wishes at any time to transfer such Restricted Note to a
                       Person in reliance on Regulation S, such owner may,
                       subject to the rules and procedures of the Euroclear or
                       Clearstream, as the case may be, exchange or cause the
                       exchange of such Restricted Note for an equivalent
                       beneficial interest in the Regulation S Global Note. Upon



                                       14
<PAGE>   19
                       receipt by the principal Registrar of (1) surrender of
                       the Restricted Note to be transferred or exchanged, (2)
                       instructions from the Company, directing the principal
                       Registrar (A) to credit or cause to be credited a
                       beneficial interest in the Regulation S Global Note equal
                       to the principal amount of the Restricted Note to be
                       exchanged or transferred and (B) to cancel such
                       Restricted Note to be exchanged or transferred, (3) a
                       written (or electronic) order given in accordance with
                       the Depositary's procedures containing information
                       regarding the participant account of the Depositary (and
                       which may include a Euroclear or Clearstream account) to
                       be credited with such increase and (4) a certificate in
                       the form of Exhibit B attached hereto given by the Holder
                       of such Restricted Note, then the principal Registrar
                       will instruct the Trustee to cancel such Restricted Note
                       and will instruct the Depositary to increase or cause to
                       be increased the principal amount of the Regulation S
                       Global Note by the principal amount of the Restricted
                       Note to be exchanged or transferred.

                          (vi) Global Note To Restricted Note. On and after such
                       time as owners of beneficial interests in Global Notes
                       are permitted under Section 2.01(d) to exchange their
                       interests in Global Notes for certificated Notes, if an
                       owner of a beneficial interest in a Global Note deposited
                       with the Depositary or with the Trustee as custodian for
                       the Depositary wishes to transfer its interest in such
                       Global Note to a Person who is required to take delivery
                       thereof in the form of a Restricted Note under Section
                       2.06(b), such owner may, subject to the rules and
                       procedures of the Depositary, cause the transfer of such
                       interest for one or more Restricted Notes of any
                       authorized denomination or denominations and of the same
                       aggregate principal amount. Subject to the terms of
                       Section 2.01(d) regarding the circumstances under which
                       owners of beneficial interests in Global Notes are
                       entitled to exchange such interests for certificated
                       Notes, upon receipt by the principal Registrar of (1)
                       instructions from the Depositary directing the principal
                       Registrar to authenticate and deliver one or more
                       Restricted Notes of the same aggregate principal amount
                       as the beneficial interest in the Global Note to be
                       transfered, such instructions to contain the name or
                       names of the designated transferee or transferees, the
                       authorized denomination or denominations of the
                       Restricted Notes to be so issued and appropriate delivery
                       instructions, (2) a certificate in the form of Exhibit D
                       attached hereto given by the owner of such beneficial
                       interest to the effect set forth therein, (3) a
                       certificate in the form of Exhibit E attached hereto
                       given by the Person acquiring the Restricted Notes for
                       which such interest is being transferred, to the effect
                       set forth therein, and (4) such other certifications,
                       legal opinions or other information as the Company may
                       reasonably require to confirm that such transfer is being
                       made pursuant to an exemption from, or in a transaction
                       not subject to, the registration requirements of the
                       Securities Act, then the principal Registrar will
                       instruct the Depositary to reduce or cause to be reduced
                       such Global Note by the aggregate principal amount of the
                       beneficial interest therein to be exchanged and to debit
                       or cause to be debited from the account of the Person
                       making such transfer the beneficial interest in the
                       Global Note that is being transferred, and concurrently
                       with such reduction and debit the Company shall execute,
                       and the Trustee shall authenticate and deliver, one or
                       more Restricted Notes of the same aggregate principal
                       amount in accordance with the instructions referred to
                       above. In the event that certificated Notes are issued in
                       place of beneficial interests in Global Notes pursuant to
                       2.01(d) prior to the effectiveness of a Shelf


                                       15
<PAGE>   20
                       Registration Statement with respect to such Notes, such
                       Notes may be exchanged only in accordance with such
                       procedures as are substantially consistent with the
                       provisions of clauses (ii) and (iii) above (including the
                       certification requirements intended to ensure that such
                       transfers comply with Rule 144A, Regulation S, Rule 144,
                       or any other available exemption from registration, as
                       the case may be) and such other procedures as may from
                       time to time be adopted by the Company.


                          (vii) Restricted Note To Restricted Note. On and after
                       such time as Holders of Accredited Investor Restricted
                       Notes or other Restricted Notes are permitted to transfer
                       such Notes other than in reliance on Regulation S or to
                       QIBs in reliance on Rule 144A in certificated form
                       pursuant to Section 2.01(d), if a Holder of a Restricted
                       Note wishes to transfer such Restricted Note to a Person
                       who is required to take delivery thereof in the form of a
                       Restricted Note, such Holder may, subject to the
                       restrictions on transfer set forth herein and in such
                       Restricted Note, cause the exchange of such Restricted
                       Note for one or more Restricted Notes of any authorized
                       denomination or denominations and of the same aggregate
                       principal amount. Upon receipt by the principal Registrar
                       of (1) such Restricted Note, duly endorsed as provided
                       herein, (2) instructions from such Holder directing the
                       principal Registrar to authenticate and deliver one or
                       more Restricted Notes of the same aggregate principal
                       amount as the Restricted Note to be exchanged, such
                       instructions to contain the name or authorized
                       denomination or denominations of the Restricted Notes to
                       be so issued and appropriate delivery instructions, (3) a
                       certificate from the Holder of the Restricted Note to be
                       exchanged in the form of Exhibit D attached hereto, (4) a
                       certificate in the form of Exhibit E attached hereto
                       given by the Person acquiring the Restricted Notes for
                       which such interest is being exchanged, if such Person is
                       an "accredited investor" as defined and to the effect set
                       forth therein, and (5) such other certifications, legal
                       opinions or other information as the Company may
                       reasonably require to confirm that such transfer is being
                       made pursuant to an exemption from, or in a transaction
                       not subject to, the registration requirements of the
                       Securities Act, then the Registrar shall cancel or cause
                       to be canceled such Restricted Note and concurrently
                       therewith, the Company shall execute, and the Trustee
                       shall authenticate and deliver, one or more Restricted
                       Notes of the same aggregate principal amount, in
                       accordance with the instructions referred to above.

                       (b) Upon any sale of a Note bearing the Restricted Notes
                    Legend (or any interest in a Global Note subject to the
                    Restricted Notes Legend) pursuant to Rule 144 under the
                    Securities Act or an effective registration statement under
                    the Securities Act:

                          (i) (A) in the case of any Note that is a certificated
                       Note or a beneficial interest in a Global Note, the
                       Registrar shall permit the Holder thereof to exchange
                       such Note or interest for a certificated Note or a
                       beneficial interest in a Global Note, as the case may be,
                       that does not bear or is subject to, as the case may be,
                       the legend set forth above and rescind any restriction on
                       the transfer of such Note or interest (1) in the case of
                       a sale or transfer pursuant to Rule 144 under the
                       Securities Act, upon delivery to the Company such
                       satisfactory evidence, which may include an opinion of
                       counsel licensed to practice law in the State of New
                       York, as may be reasonably required by the Company, that
                       neither the legend nor the restrictions on transfer set



                                       16
<PAGE>   21
                       forth therein are required to ensure that transfers
                       thereof comply with the provisions of Rule 144A, Rule
                       144, Regulation S or any other available exemption from
                       registration under the Securities Act or, with respect to
                       Restricted Notes, that such Notes are not "restricted"
                       within the meaning of Rule 144 under the Securities Act
                       or (2) in the case of a sale or transfer pursuant to an
                       effective registration statement under the Securities
                       Act; and

                          (ii) any Global Note shall not be subject to the
                       Restricted Notes Legend (such sales or transfers being
                       subject only to the provisions of Section 2.06(a)(i) and
                       Section 2.01(d)).


                  Upon provision of such satisfactory evidence, the Trustee, at
         the direction of the Company, shall authenticate and deliver Notes that
         do not bear the Restricted Notes Legend.

                  (c) Neither the Company nor the Trustee shall have any
         responsibility for any actions taken or not taken by the Depositary and
         the Company shall have no responsibility for any actions taken or not
         taken by the Trustee as agent or custodian of the Depositary.

                  (d) Notwithstanding anything contained herein to the contrary,
         neither the Trustee nor the Note Registrar shall be responsible for
         ascertaining whether any purchase or transfer complies with the
         registration provisions of or exemptions from the Securities Act, Rule
         144A, Rule 144, Regulation S, or any applicable state securities laws;
         provided, that if a certificate or other written representation is
         specifically required by the express terms of this Section 2.06 to be
         delivered to the Registrar or Trustee by a transferee of a Note prior
         to registration of such transfer, the Trustee or Note Registrar, as the
         case may be, shall be under a duty to receive and examine the same to
         determine whether it conforms on its face to the requirements of this
         Section 2.06.


                  (e) Transfers of any Notes in certificated form not bearing
         the Restricted Notes Legend shall not be subject to the restrictions
         and requirements set forth in Section 2.06(a)(vii).

                  (f) Any transfer or exchange of a Note in certificated form
         shall be accompanied by surrender of the certificated Note, endorsed or
         accompanied by an instrument of transfer acceptable to the Registrar,
         executed by the Holder or an attorney in fact acting on its behalf.

SECTION 2.07.     REPLACEMENT NOTES.


                  If the Holder of a Note claims that the Note has been lost,
         destroyed or wrongfully taken or if such Note is mutilated and is
         surrendered to the Trustee, the Company shall issue and the Trustee
         shall authenticate a replacement Note if the Trustee's and the
         Company's requirements are met. If required by the Trustee or the
         Company, an indemnity bond must be supplied by the Holder that is
         sufficient in the judgment of both to protect the Company, the Trustee,
         any Agent or any authenticating agent from any loss which any of them
         may suffer if a Note is replaced. The Company may charge for its
         expenses in replacing a Note.


                  In case any such mutilated, destroyed, lost or stolen Note has
         become or is about to become due and payable, or is about to be
         purchased by the Company pursuant to Article III

                                       17
<PAGE>   22
                  hereof, the Company in its discretion may, instead of issuing
                  a new Note, pay or purchase such Note, as the case may be.


                  Every replacement Note is an additional obligation of the
         Company and shall be entitled to all of the benefits of this Indenture
         equally and proportionately with all other Notes duly issued hereunder.

SECTION 2.08.     OUTSTANDING NOTES.


                  The Notes outstanding at any time are all the Notes
         authenticated by the Trustee except for those canceled by it, those
         delivered to it for cancellation, and those described in this Section
         as not outstanding.


                  If a Note is replaced, paid or purchased pursuant to Section
         2.07 hereof, it ceases to be outstanding unless the Trustee receives
         proof satisfactory to it that the replaced, paid or purchased Note is
         held by a bona fide purchaser.


                  If the principal amount of any Note is considered paid under
         Section 4.01 hereof, it ceases to be outstanding and interest on it
         ceases to accrue.


                  Except as set forth in Section 2.09 hereof, a Note does not
         cease to be outstanding because the Company or an Affiliate of the
         Company holds the Note.

SECTION 2.09.     TREASURY NOTES.


                  In determining whether the Holders of the required principal
         amount of Notes have concurred in any direction, waiver or consent,
         Notes owned by the Company or an Affiliate of the Company shall be
         considered as though they are not outstanding, except that for the
         purposes of determining whether the Trustee shall be protected in
         relying on any such direction, waiver or consent, only Notes that the
         Trustee knows are so owned shall be so disregarded.

SECTION 2.10.     TEMPORARY NOTES; GLOBAL NOTES.

                  (a) Until definitive Notes are ready for delivery, the Company
         may prepare and the Trustee shall authenticate temporary Notes.
         Temporary Notes shall be substantially in the form of definitive Notes
         but may have variations that the Company considers appropriate for
         temporary Notes. Without unreasonable delay, the Company shall prepare
         and the Trustee shall authenticate definitive Notes in exchange for
         temporary Notes. Holders of temporary Notes shall be entitled to all of
         the benefits of this Indenture.

                  (b) A Global Note deposited with the Depositary or with the
         Trustee as custodian for the Depositary pursuant to Section 2.01 shall
         be transferred to the beneficial owners thereof in the form of
         certificated Notes only (i) in accordance with Section 2.01(d), and
         (ii) provided that such transfer complies with the applicable
         provisions of Section 2.06(b).

                  (c) Any Global Note that is re-issued to the beneficial owners
         thereof in the form of certificated Notes pursuant to Section 2.01(d)
         and this Section 2.10 shall be surrendered by

                                       18
<PAGE>   23
         the Depositary to the Trustee to be so transferred without charge, and
         the Trustee shall authenticate and deliver, upon such transfer of each
         portion of such Global Note, an equal aggregate principal amount of
         Notes of authorized denominations in the form of certificated Notes.
         Any portion of a Global Note transferred pursuant to this Section 2.10
         shall be executed, authenticated and delivered as the Depositary shall
         direct. Any Note in the form of certificated Notes delivered in
         exchange for an interest in the Global Notes shall, except as otherwise
         provided by Section 2.06(c), bear the Restricted Notes Legend set forth
         in Exhibit A hereto.

                  (d) Upon the occurrence of any of the events set forth in
         Section 2.01(d) requiring the issuance of certificated Notes in place
         of all beneficial interests in Global Notes then outstanding, the
         Company will promptly make available to the Trustee a reasonable supply
         of certificated Notes in definitive, fully registered form without
         interest coupons.

SECTION 2.11.     CANCELLATION.


                  The Company at any time may deliver Notes to the Trustee for
         cancellation. The Registrar, Paying Agent and Conversion Agent shall
         forward to the Trustee any Notes surrendered to them for registration
         of transfer, exchange or payment. The Trustee shall promptly cancel all
         Notes surrendered for registration of transfer, exchange, payment,
         conversion, replacement or cancellation and shall dispose of canceled
         Notes as the Company directs. The Company may not issue new Notes to
         replace Notes that it has paid or that have been delivered to the
         Trustee for cancellation.

SECTION 2.12.     DEFAULTED INTEREST.


                  If the Company fails to make a payment of interest on the
         Notes, it shall pay such defaulted interest plus any interest payable
         on the defaulted interest, in any lawful manner. It may pay such
         defaulted interest, plus any such interest payable on it, to the
         Persons who are Holders on a subsequent special record date. The
         Company shall fix any such record date and payment date, provided that
         no such record date shall be less than 10 days prior to the related
         payment date for such defaulted interest. At least 15 days before any
         such record date, the Company shall mail to Holders a notice that
         states the special record date, the related payment date and amount of
         such interest to be paid.

SECTION 2.13.     CUSIP NUMBERS.


                  The Company in issuing the Notes may use "CUSIP" numbers (if
         then generally in use), and, if so, the Trustee shall use "CUSIP"
         numbers in notices of redemption and other notices as a convenience to
         holders of Notes; provided, that any such notice may state that no
         representation is made as to the correctness of such numbers either as
         printed on the Notes or as contained in any notice of a redemption or
         notice of a Purchase Offer and that reliance may be placed only on the
         other identification numbers printed on the Notes, and any redemption
         or Purchase Offer shall not be affected by any defect in or omission of
         such numbers. The Company will promptly notify the Trustee of any
         change in the "CUSIP" numbers.

                                       19
<PAGE>   24
                                  ARTICLE III
                                   REDEMPTION

SECTION 3.01.    NOTICES TO TRUSTEE.


                  If the Company elects to redeem Notes pursuant to the optional
         redemption provisions of the Notes and Section 3.07 hereof, it shall
         notify the Trustee in writing of the redemption date and the principal
         amount of Notes to be redeemed. The Company shall give the notice
         provided for in this Section 3.01 at least 45 days before the
         redemption date, unless a shorter notice period shall be satisfactory
         to the Trustee. The Company may not give notice of any redemption if
         the Company has defaulted in payment of interest and the default is
         continuing.

SECTION 3.02.     SELECTION OF NOTES TO BE REDEEMED.


                  If less than all of the Notes are to be redeemed at any time,
         selection of Notes shall be made by the Trustee on a pro rata basis or
         by lot or by a method that complies with the requirements of any
         exchange on which the Notes are listed and that the Trustee considers
         fair and appropriate, provided that no Notes of $1,000 or less shall be
         redeemed in part. The Trustee shall make the selection not more than 60
         days and not less than 30 days before the redemption date from Notes
         outstanding not previously called for redemption. Notes and portions of
         Notes selected shall be in amounts of $1,000 or integral multiples of
         $1,000. Provisions of this Indenture that apply to Notes called for
         redemption also apply to portions of Notes called for redemption. The
         Trustee shall notify the Company promptly of the Notes or portions of
         Notes to be called for redemption.


                  If any Note selected for partial redemption is converted in
         part after such selection, the converted portion of such Note shall be
         deemed (so far as may be) to be the portion to be selected for
         redemption. The Notes (or portions thereof) so selected shall be deemed
         duly selected for redemption for all purposes hereunder,
         notwithstanding that any such Note is converted in whole or in part
         before the mailing of the notice of redemption. Upon any redemption of
         less than all the Notes, the Company and the Trustee may treat as
         outstanding any Notes surrendered for conversion during the period 15
         days next preceding the mailing of a notice of redemption and need not
         treat as outstanding any Note authenticated and delivered during such
         period in exchange for the unconverted portion of any Note converted in
         part during such period.

SECTION 3.03.     NOTICE OF REDEMPTION.


                  At least 30 days but not more than 60 days before a redemption
         date, the Company shall mail, by first class mail, a notice of
         redemption to each Holder whose Notes are to be redeemed at its
         registered address. The notice shall identify the Notes to be redeemed
         and shall state:

                  (a) the redemption date;

                  (b) the redemption price;

                                       20
<PAGE>   25

                  (c) if any Note is to be redeemed in part only, the portion of
         the principal amount thereof redeemed, and that, after the redemption
         date, upon surrender of such Note, a new Note in principal amount equal
         to the unredeemed portion thereof shall be issued in the name of the
         Holder thereof upon cancellation of the original Note;

                  (d) the name and address of the Paying Agent;

                  (e) that Notes called for redemption must be surrendered to
         the Paying Agent to collect the redemption price plus accrued interest,
         if any;

                  (f) that interest on Notes called for redemption ceases to
         accrue on and after the redemption date;

                  (g) the paragraph of the Notes pursuant to which the Notes
         called for redemption are being redeemed; and

                  (h) the "CUSIP" number of the Notes to be redeemed; and

                  (i) the current Conversion Price and the date on which the
         right to convert such Notes or portions thereof into Common Stock of
         the Company will expire.


                  At the Company's request, the Trustee shall give notice of
         redemption in the Company's name and at the Company's expense; provided
         that the Company shall have delivered to the Trustee, at least 45 days
         prior to the redemption date, an Officers' Certificate requesting that
         the Trustee give such notice and setting forth the information to be
         stated in such notice, as provided in the preceding paragraph.

SECTION 3.04.     EFFECT OF NOTICE OF REDEMPTION.


                  Once notice of redemption is mailed in accordance with Section
         3.03 hereof, Notes called for redemption become due and payable on the
         redemption date at the price set forth in the Note. A notice of
         redemption may not be conditional.

SECTION 3.05.     DEPOSIT OF REDEMPTION PRICE.


                  On or before 1:00 pm (Boston time) on the redemption date, the
         Company shall deposit with the Trustee or with the Paying Agent money
         (in immediately available funds) sufficient to pay the redemption price
         of and accrued interest on all Notes to be redeemed on that date unless
         theretofore converted into Common Stock pursuant to the provisions
         hereof. The Trustee or the Paying Agent shall return to the Company any
         money not required for that purpose.

SECTION 3.06.     NOTES REDEEMED IN PART.


                  Upon surrender of a Note that is redeemed in part, the Company
         shall issue and the Trustee shall authenticate for the Holder at the
         expense of the Company a new Note equal in principal amount to the
         unredeemed portion of the Note surrendered.



                                       21
<PAGE>   26
SECTION 3.07.     OPTIONAL REDEMPTION.


                  The Company may redeem all or any portion of the Notes, upon
         the terms and at the redemption prices set forth in the Notes. Any
         redemption pursuant to this Section 3.07 shall be made pursuant to the
         provisions of Section 3.01 through 3.06 hereof.

SECTION 3.08.     MANDATORY REDEMPTION.


                  The Company shall not be required to make mandatory redemption
         payments or sinking fund payments with respect to the Notes.

SECTION 3.09.     PURCHASE OFFER.

                  (a) In the event that, pursuant to Section 4.07 hereof, the
         Company shall commence an offer to all Holders of the Notes to purchase
         Notes (the "PURCHASE OFFER"), the Company shall follow the procedures
         in this Section 3.09.

                  (b) The Purchase Offer shall remain open for a period
         specified by the Company which shall be no less than 30 calendar days
         and no more than 45 calendar days following its commencement (the
         "COMMENCEMENT DATE") (as determined in accordance with Section 4.07
         hereof), except to the extent that a longer period is required by
         applicable law (the "TENDER PERIOD"). Upon the expiration of the Tender
         Period (the "PURCHASE DATE"), the Company shall purchase the principal
         amount of all of the Notes required to be purchased pursuant to Section
         4.07 hereof (the "OFFER AMOUNT").

                  (c) If the Purchase Date is on or after an interest payment
         record date and on or before the related interest payment date, any
         accrued interest shall be paid to the Person in whose name a Note is
         registered at the close of business on such record date, and no
         additional interest will be payable to Holders who tender Notes
         pursuant to the Purchase Offer.

                  (d) The Company shall provide the Trustee with written notice
         of the Purchase Offer at least 10 days before the Commencement Date.

                  (e) On or before the Commencement Date, the Company or the
         Trustee (at the written request and expense of the Company, the Company
         having provided to the Trustee the requisite information therefor)
         shall send, by first class mail, a notice to each of the Holders, which
         shall govern the terms of the Purchase Offer and shall state:

                           (i) that the Purchase Offer is being made pursuant to
                  this Section 3.09 and Section 4.07 hereof, that all Notes
                  validly tendered will be accepted for payment and the length
                  of time the Purchase Offer will remain open;


                           (ii) the purchase price (as determined in accordance
                  with Section 4.07 hereof) and the Purchase Date, and that all
                  Notes tendered will be accepted for payment;


                           (iii) that any Note or portion thereof not tendered
                  or accepted for payment will continue to accrue interest;





                                       22
<PAGE>   27

                           (iv) that, unless the Company defaults in the payment
                  of the purchase price, any Note or portion thereof accepted
                  for payment pursuant to the Purchase Offer will cease to
                  accrue interest after the Purchase Date;


                           (v) that Holders electing to have a Note or portion
                  thereof purchased pursuant to any Purchase Offer will be
                  required to surrender the Note, with the form entitled "Option
                  of Holder to Elect Purchase" on the reverse of the Note
                  completed, to the Company, a depositary, if appointed by the
                  Company, or a Paying Agent at the address specified in the
                  notice prior to the close of business on the third Business
                  Day preceding the Purchase Date;


                           (vi) that Holders will be entitled to withdraw their
                  election if the Company, depositary or Paying Agent, as the
                  case may be, receives, not later than the close of business on
                  the second Business Day preceding the Purchase Date, or such
                  longer period as may be required by law, a letter or a
                  telegram, telex or facsimile transmission (receipt of which is
                  confirmed and promptly followed by a letter) setting forth the
                  name of the Holder, the principal amount of the Note or
                  portion thereof the Holder delivered for purchase and a
                  statement that such Holder is withdrawing his election to have
                  the Note or portion thereof purchased;


                           (vii) that Holders whose Notes were purchased only in
                  part will be issued new Notes equal in principal amount to the
                  unpurchased portion of the Notes surrendered and


                           (viii) the "CUSIP" number of the Notes to be
                  purchased.


                         (f) On or prior to 1:00 pm (Boston time) on the
          Purchase Date, the Company shall irrevocably deposit with the Trustee
          or a Paying Agent in immediately available funds an amount equal to
          the Offer Amount to be held for payment in accordance with the terms
          of this Section 3.09. On the Purchase Date, the Company shall, to the
          extent lawful, (i) accept for payment the Notes or portions thereof
          properly tendered pursuant to the Purchase Offer, (ii) deliver or
          cause the Depositary or Paying Agent to deliver to the Trustee Notes
          so accepted and (iii) deliver to the Trustee an Officers' Certificate
          stating such Notes or portions thereof have been accepted for payment
          by the Company in accordance with the terms of this Section 3.09. The
          Depositary, the Paying Agent or the Company, as the case may be, shall
          promptly (but in any case not later than ten (10) calendar days after
          the Purchase Date) mail or deliver to each tendering Holder an amount
          equal to the purchase price of the Notes tendered by such Holder and
          accepted by the Company for purchase, and the Trustee shall promptly
          authenticate and mail or deliver to such Holders a new Note equal in
          principal amount to any unpurchased portion of the Note surrendered.
          Any Notes not so accepted shall be promptly mailed or delivered by or
          on behalf of the Company to the Holder thereof. The Company will
          publicly announce in a newspaper of general circulation the results of
          the Purchase Offer on or as soon as practicable after the Purchase
          Date.




                                       23
<PAGE>   28

                  The Purchase Offer shall be made by the Company in compliance
         with all applicable provisions of the Exchange Act, and all applicable
         tender offer rules promulgated thereunder, and shall include all
         instructions and materials necessary to enable such Holders to tender
         their Notes.


                                   ARTICLE IV
                                    COVENANTS

SECTION 4.01.     PAYMENT OF NOTES.


                  The Company shall pay the principal of, and premium, if any,
         and interest on, the Notes on the dates and in the manner provided in
         the Notes. Principal, premium, if any, and interest shall be considered
         paid on the date due if the Paying Agent (other than the Company or an
         Affiliate of the Company) holds on that date money designated for and
         sufficient to pay all principal, premium, if any, and interest then
         due. To the extent lawful, the Company shall pay interest (including
         post-petition interest in any proceeding under any Bankruptcy Law) on
         (i) overdue principal and premium, if any, at the rate borne by the
         Notes, compounded semiannually; and (ii) overdue installments of
         interest (without regard to any applicable grace period) at the same
         rate, compounded semiannually.


                  Whenever in this Indenture or the Notes there is mentioned, in
         any context, the payment of principal (and premium, if any), Offer
         Amount, interest or any other amount payable under or with respect to
         any Note, such mention shall be deemed to include mention of the
         payment of Special Interest provided for in Section 2 of the Notes to
         the extent that, in such context, Special Interest is, was or would be
         payable in respect thereof pursuant to the provisions of Section 2 of
         the Notes, and express mention of the payment of Special Interest (if
         applicable) in any provisions hereof shall not be construed as
         excluding Special Interest in those provisions hereof where such
         express mention is not made (if applicable).

SECTION 4.02      REPORTS.


                  Whether or not required by the rules and regulations of the
         SEC, so long as any Notes are outstanding, the Company shall file with
         the SEC and furnish to the Trustee and to the Holders of Notes, all
         quarterly and annual financial information required to be contained in
         a filing with the SEC on Forms 10-Q and 10-K, including a "Management's
         Discussion and Analysis of Results of Operations and Financial
         Condition" and, with respect to the annual information only, a report
         thereon by the Company's certified independent accountants, in each
         case, as required by the rules and regulations of the SEC as in effect
         on the Issuance Date. The Trustee shall be under no obligation or duty
         to review such reports, such delivery to it being for the purpose of
         having the same on file with the Trustee and available for examination.

SECTION 4.03.     COMPLIANCE CERTIFICATE.


                           The Company shall deliver to the Trustee, within 90
                  days after the end of each fiscal year of the Company, an
                  Officers' Certificate stating that a review of the activities
                  of the

                                       24
<PAGE>   29

                  Company and its subsidiaries during the preceding fiscal year
                  has been made under the supervision of the signing Officers
                  with a view to determining whether the Company has kept,
                  observed, performed and fulfilled its obligations under, and
                  complied with the covenants and conditions contained in, this
                  Indenture, and further stating, as to each such Officer
                  signing such certificate, that to the best of his knowledge
                  the Company has kept, observed, performed and fulfilled each
                  and every covenant, and complied with the covenants and
                  conditions contained in this Indenture and is not in default
                  in the performance or observance of any of the terms,
                  provisions and conditions hereof (or, if a Default or Event of
                  Default shall have occurred, describing all such Defaults or
                  Events of Default of which he may have knowledge) and that to
                  the best of his knowledge no event has occurred and remains in
                  existence by reason of which payments on account of the
                  principal or of interest, if any, on the Notes are prohibited.
                  One of the Officers signing such Officers' Certificate shall
                  be either the Company's principal executive officer, principal
                  financial officer or principal accounting officer.


                           The Company will, so long as any of the Notes are
                  outstanding, deliver to the Trustee forthwith upon becoming
                  aware of any Default or Event of Default, an Officers'
                  Certificate specifying such Default or Event of Default.


                           Immediately upon the occurrence of any Registration
                  Default giving rise to Special Interest or the cure of any
                  such Registration Default, the Company shall give the Trustee
                  written notice thereof and of the event giving rise to such
                  Registration Default or the cure of any such Registration
                  Default (such notice to be contained in an Officers'
                  Certificate) and prior to receipt of such Officers'
                  Certificate the Trustee shall be entitled to assume that no
                  such Registration Default has occurred or been cured, as the
                  case may be.

SECTION 4.04.     STAY, EXTENSION AND USURY LAWS.


                           The Company covenants (to the extent that it may
                  lawfully do so) that it will not at any time insist upon,
                  plead, or in any manner whatsoever claim or take the benefit
                  or advantage of, any stay, extension or usury law wherever
                  enacted, now or at any time hereafter in force, which may
                  affect the covenants or the performance of this Indenture; and
                  the Company (to the extent it may lawfully do so) hereby
                  expressly waives all benefit or advantage of any such law, and
                  covenants that it will not, by resort to any such law, hinder,
                  delay or impede the execution of any power herein granted to
                  the Trustee, but will suffer and permit the execution of every
                  such power as though no such law had been enacted.

SECTION 4.05.     CORPORATE EXISTENCE.


                           Subject to Article VII hereof, to the extent
                  permitted by law the Company will do or cause to be done all
                  things necessary to preserve and keep in full force and effect
                  its corporate existence and the corporate, partnership or
                  other existence of each subsidiary of the Company in
                  accordance with the respective organizational documents of
                  each subsidiary and the rights (charter and statutory),
                  licenses and franchises of the Company; provided, however,
                  that the Company shall not be required to preserve any such
                  right, license or franchise, or the corporate, partnership or
                  other existence of any subsidiary, if the preservation thereof
                  is no


                                       25
<PAGE>   30

                  longer desirable in the conduct of the business of the Company
                  and its subsidiaries taken as a whole.

SECTION 4.06.     TAXES.


                           The Company shall, and shall cause each of its
                  subsidiaries to, pay prior to delinquency all material taxes,
                  assessments and governmental levies, except as contested in
                  good faith and by appropriate proceedings.

SECTION 4.07.     FUNDAMENTAL CHANGE.

                           (a) Upon the occurrence of a Fundamental Change, each
                  Holder of Notes shall have the right to require the Company to
                  repurchase all or any part (equal to $1,000 or an integral
                  multiple thereof) of such Holder's Notes pursuant to the
                  Purchase Offer at a purchase price equal to 100% of the
                  principal amount thereof plus accrued and unpaid interest to
                  the date of purchase (the "FUNDAMENTAL CHANGE PAYMENT").

                           (b) Within 25 days following any Fundamental Change,
                  the Company shall give written notice to the Trustee and shall
                  mail to each Holder the notice provided by Section 3.09(e).

SECTION 4.08.     LIMITATION ON STATUS AS INVESTMENT COMPANY.


                           The Company shall not, and shall not permit any
                  Subsidiary to, conduct its business in a fashion that would
                  cause the Company to be required to be registered as an
                  "investment company" (as that term is defined in the
                  Investment Company Act of 1940, as amended).

SECTION 4.09.     SPECIAL INTEREST.


                           If Special Interest is payable by the Company
                  pursuant to Section 2 of the Notes, the Company shall deliver
                  to the Trustee a certificate to that effect stating (i) the
                  amount of such Special Interest that is payable and (ii) the
                  date on which such Special Interest is payable. Unless and
                  until a Trust Officer of the Trustee receives such a
                  certificate, the Trustee may assume without inquiry that no
                  such Special Interest is payable. If the Company has paid
                  Special Interest directly to the persons entitled to it, the
                  Company shall deliver to the Trustee a certificate setting
                  forth the particulars of such payment.

                                   ARTICLE V
                                   CONVERSION

SECTION 5.01.     CONVERSION PRIVILEGE.


                  A Holder of a Note may convert it into fully paid and
         nonassessable shares of Common Stock at any time following the Issuance
         Date and prior to maturity at the Conversion Price then in effect,
         except that, with respect to any Note called for redemption, such
         conversion right shall terminate at the close of business on the
         Business Day immediately preceding the redemption date (unless the
         Company shall default in making the redemption payment when it becomes
         due, in which case the conversion right shall terminate



                                       26
<PAGE>   31

         on the date such default is cured). The number of shares of Common
         Stock issuable upon conversion of a Note is determined by dividing the
         principal amount of such Note by the conversion price in effect on the
         Conversion Date (the "CONVERSION PRICE").


                  The initial Conversion Price is stated in Section 12 of the
         Notes and is subject to adjustment as provided in this Article V.


                  A Holder may convert a portion of a Note equal to any integral
         multiple of $1,000. Provisions of this Indenture that apply to
         conversion of all of a Note also apply to conversion of a portion of
         it.

SECTION 5.02.     CONVERSION PROCEDURE.


                  To convert a Note, a Holder must satisfy the requirements in
         Section 12 of the Notes. The date on which the Holder satisfies all of
         those requirements is the conversion date (the "CONVERSION DATE"). As
         soon as practicable after the Conversion Date, the Company shall
         deliver to the Holder through the Conversion Agent a certificate for
         the number of whole shares of Common Stock issuable upon the conversion
         and a check for any fractional share determined pursuant to Section
         5.03 hereof. The Person in whose name the certificate is registered
         shall become the stockholder of record on the Conversion Date and, as
         of such date, such Person's rights as a Holder of Notes hereunder shall
         cease (such Person's rights as a Holder of Transfer Restricted
         Securities, if any, under the Registration Rights Agreement, however,
         shall continue so long as such Person holds such Transfer Restricted
         Securities); provided, however, that no surrender of a Note on any date
         when the stock transfer books of the Company shall be closed shall be
         effective to constitute the Person entitled to receive the shares of
         Common Stock upon such conversion as the stockholder of record of such
         shares of Common Stock on such date, but such surrender shall be
         effective to constitute the Person entitled to receive such shares of
         Common Stock as the stockholder of record thereof for all purposes at
         the close of business on the next succeeding day on which such stock
         transfer books are open; provided further, however, that such
         conversion shall be at the Conversion Price in effect on the date that
         such Note shall have been surrendered for conversion, as if the stock
         transfer books of the Company had not been closed.


                  No payment or adjustment will be made for accrued and unpaid
         interest on a converted Note, but if any Holder surrenders a Note for
         conversion after the close of business on the record date for the
         payment of an installment of interest and prior to the opening of
         business on the next interest payment date, then, notwithstanding such
         conversion, the interest payable on such interest payment date shall be
         paid to the Holder of such Note on such record date. Any Notes that
         are, however, delivered to the Company for conversion after any record
         date but before the next interest payment date must, except as
         described in the next sentence, be accompanied by a payment equal to
         the interest payable on such interest payment date on the principal
         amount of convertible notes being converted. The payment to the Company
         described in the preceding sentence shall not be required if, during
         that period between a record date and the next interest payment date, a
         conversion occurs on or after the date that the Company has issued a
         redemption notice and prior to the date of redemption stated in such
         notice. If any Notes are converted after an interest payment date but
         on or before the next


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         record date, no interest will be paid on those Notes. No fractional
         shares will be issued upon conversion, but a cash adjustment will be
         made for any fractional shares.


                  If a Holder converts more than one Note at the same time, the
         number of whole shares of Common Stock issuable upon the conversion
         shall be based on the total principal amount of Notes converted.


                  Upon surrender of a Note that is converted in part, the
         Trustee shall authenticate for the Holder a new Note equal in principal
         amount to the unconverted portion of the Note surrendered.

SECTION 5.03.     FRACTIONAL SHARES.


                  The Company will not issue fractional shares of Common Stock
         upon conversion of a Note. In lieu thereof, the Company will pay an
         amount in cash based upon the Daily Market Price of the Common Stock on
         the trading day prior to the date of conversion.

SECTION 5.04.     TAXES ON CONVERSION.


                  The issuance of certificates for shares of Common Stock upon
         the conversion of any Note shall be made without charge to the
         converting Holder for such certificates or for any tax in respect of
         the issuance of such certificates, and such certificates shall be
         issued in the respective names of, or in such names as may be directed
         by, the Holder or Holders of the converted Note; provided, however,
         that in the event that certificates for shares of Common Stock are to
         be issued in a name other than the name of the Holder of the Note
         converted, such Note, when surrendered for conversion, shall be
         accompanied by an instrument of transfer, in form satisfactory to the
         Company, duly executed by the registered Holder thereof or his duly
         authorized attorney; and provided further, however, that the Company
         shall not be required to pay any tax which may be payable in respect of
         any transfer involved in the issuance and delivery of any such
         certificates in a name other than that of the Holder of the converted
         Note, and the Company shall not be required to issue or deliver such
         certificates unless or until the Person or Persons requesting the
         issuance thereof shall have paid to the Company the amount of such tax
         or shall have established to the satisfaction of the Company that such
         tax has been paid or is not applicable.

SECTION 5.05.     COMPANY TO PROVIDE STOCK.


                  The Company shall at all times reserve and keep available,
         free from preemptive rights, out of its authorized but unissued Common
         Stock, solely for the purpose of issuance upon conversion of Notes as
         herein provided, a sufficient number of shares of Common Stock to
         permit the conversion of all outstanding Notes for shares of Common
         Stock. All shares of Common Stock which may be issued upon conversion
         of the Notes shall be duly authorized, validly issued, fully paid and
         nonassessable when so issued. Shares of Common Stock issuable upon
         conversion of a Restricted Note shall bear such restrictive legends as
         the Company shall provide in accordance with applicable law. If shares
         of Common Stock are to be issued upon conversion of a Restricted Note
         and they are to be registered in a name other than that of the holder
         of such Restricted Note, then the Person in whose name such shares of
         Common Stock are to be registered must deliver to the Trustee a
         certificate satisfactory to the



                                       28
<PAGE>   33

         Company and signed by such Person as to compliance with the
         restrictions on transfer contained in such restrictive legends.

SECTION 5.06.     ADJUSTMENT OF CONVERSION PRICE.


                  The Conversion Price shall be subject to adjustment from time
         to time as follows:

                  (a) In case the Company shall (1) pay a dividend in shares of
         Common Stock to holders of Common Stock, (2) make a distribution in
         shares of Common Stock to holders of Common Stock, (3) subdivide its
         outstanding shares of Common Stock into a greater number of shares of
         Common Stock or (4) combine its outstanding shares of Common Stock into
         a smaller number of shares of Common Stock, the Conversion Price in
         effect immediately prior to such action shall be adjusted so that the
         Holder of any Note thereafter surrendered for conversion shall be
         entitled to receive the number of shares of Common Stock which he would
         have owned immediately following such action had such Notes been
         converted immediately prior thereto. Any adjustment made pursuant to
         this subsection (a) shall become effective immediately after the record
         date in the case of a dividend or distribution and shall become
         effective immediately after the effective date in the case of a
         subdivision or combination.

                  (b) In case the Company shall issue rights or warrants to
         substantially all holders of Common Stock entitling them (for a period
         commencing no earlier than the record date for the determination of
         holders of Common Stock entitled to receive such rights or warrants and
         expiring not more than 45 days after such record date) to subscribe for
         or purchase shares of Common Stock (or securities convertible into
         Common Stock) at a price per share less than the current market price
         (as determined pursuant to subsection (f) below) of the Common Stock on
         such record date, the Conversion Price shall be adjusted so that the
         same shall equal the price determined by multiplying the Conversion
         Price in effect immediately prior to such record date by a fraction of
         which the numerator shall be the number of shares of Common Stock
         outstanding on such record date, plus the number of shares of Common
         Stock which the aggregate offering price of the offered shares of
         Common Stock (or the aggregate conversion price of the convertible
         securities so offered) would purchase at such current market price, and
         of which the denominator shall be the number of shares of Common Stock
         outstanding on such record date plus the number of additional shares of
         Common Stock offered (or into which the convertible securities so
         offered are convertible). Such adjustments shall become effective
         immediately after such record date.

                  (c) In case the Company shall distribute to all holders of
         Common Stock shares of capital stock of the Company other than Common
         Stock, evidences of indebtedness or other assets (other than cash
         dividends out of current or retained earnings), or shall distribute to
         substantially all holders of Common Stock rights or warrants to
         subscribe for securities (other than those referred to in subsection
         (b) above), then in each such case the Conversion Price shall be
         adjusted so that the same shall equal the price determined by
         multiplying the Conversion Price in effect immediately prior to the
         date of such distribution by a fraction of which the numerator shall be
         the current market price (determined as provided in subsection (f)
         below) of the Common Stock on the record date mentioned below less the
         then fair market value (as determined by the Board of Directors, whose
         determination shall be



                                       29
<PAGE>   34

         conclusive evidence of such fair market value and described in a Board
         Resolution) of the portion of the assets so distributed or of such
         subscription rights or warrants applicable to one share of Common
         Stock, and of which the denominator shall be such current market price
         of the Common Stock. Such adjustment shall become effective immediately
         after the record date for the determination of the holders of Common
         Stock entitled to receive such distribution. Notwithstanding the
         foregoing, in the event that the Company shall distribute rights or
         warrants (other than those referred to in subsection (b) above)
         ("RIGHTS") pro rata to holders of Common Stock, the Company may, in
         lieu of making any adjustment pursuant to this Section 5.06, make
         proper provision so that each Holder of a Note who converts such Note
         (or any portion thereof) after the record date for such distribution
         and prior to the expiration or redemption of the Rights shall be
         entitled to receive upon such conversion, in addition to the shares of
         Common Stock issuable upon such conversion (the "CONVERSION SHARES"), a
         number of Rights to be determined as follows: (i) if such conversion
         occurs on or prior to the date for the distribution to the holders of
         Rights of separate certificates evidencing such Rights (the
         "DISTRIBUTION DATE"), the same number of Rights to which a holder of a
         number of shares of Common Stock equal to the number of Conversion
         Shares is entitled at the time of such conversion in accordance with
         the terms and provisions of and applicable to the Rights; and (ii) if
         such conversion occurs after the Distribution Date, the same number of
         Rights to which a holder of the number of shares of Common Stock into
         which the principal amount of the Note so converted was convertible
         immediately prior to the Distribution Date would have been entitled on
         the Distribution Date in accordance with the terms and provisions of
         and applicable to the Rights.

                  (d) In case the Company shall, by dividend or otherwise, at
         any time distribute to all holders of its Common Stock cash (including
         any distributions of cash out of current or retained earnings of the
         Company but excluding any cash that is distributed as part of a
         distribution requiring a Conversion Price adjustment pursuant to
         paragraph (c) of this Section 5.06) in an aggregate amount that,
         together with the sum of (x) the aggregate amount of any other
         distributions to all holders of its Common Stock made in cash plus (y)
         all Excess Payments, in each case made within the 12 months preceding
         the date fixed for determining the stockholders entitled to such
         distribution (the "DISTRIBUTION RECORD DATE") and in respect of which
         no Conversion Price adjustment pursuant to paragraphs (c) or (e) of
         this Section 5.06 or this paragraph (d) has been made, exceeds 15% of
         the product of the current market price per share (determined as
         provided in paragraph (f) of this Section 5.06) of the Common Stock on
         the Distribution Record Date times the number of shares of Common Stock
         outstanding on the Distribution Record Date (excluding shares held in
         the treasury of the Company), the Conversion Price shall be reduced so
         that the same shall equal the price determined by multiplying such
         Conversion Price in effect immediately prior to the effectiveness of
         the Conversion Price reduction contemplated by this paragraph (d) by a
         fraction of which the numerator shall be the current market price per
         share (determined as provided in paragraph (f) of this Section 5.06) of
         the Common Stock on the Distribution Record Date less the amount of
         such cash and other consideration (including any Excess Payments) so
         distributed applicable to one share (based on the pro rata portion of
         the aggregate amount of such cash and other consideration (including
         any Excess Payments), divided by the shares of Common Stock outstanding
         on the Distribution Record Date) of Common Stock and the denominator
         shall be such current market price per share (determined as provided in
         paragraph (f) of this Section 5.06) of the Common Stock on the
         Distribution



                                       30
<PAGE>   35

         Record Date, such reduction to become effective immediately prior to
         the opening of business on the day following the Distribution Record
         Date.

                  (e) In case a tender offer or other negotiated transaction
         made by the Company or any Subsidiary for all or any portion of the
         Common Stock shall be consummated, if an Excess Payment is made in
         respect of such tender offer or other negotiated transaction and the
         amount of such Excess Payment, together with the sum of (x) the
         aggregate amount of all Excess Payments plus (y) the aggregate amount
         of all distributions to all holders of the Common Stock made in cash
         (specifically including distributions of cash out of retained
         earnings), in each case made within the 12 months preceding the date of
         payment of such current negotiated transaction consideration or
         expiration of such current tender offer, as the case may be (the
         "PURCHASE DATE"), and as to which no adjustment pursuant to paragraph
         (c) or paragraph (d) of this Section 5.06 or this paragraph (e) has
         been made, exceeds 15% of the product of the current market price per
         share (determined as provided in paragraph (f) of this Section 5.06) of
         the Common Stock on the Purchase Date times the number of shares of
         Common Stock outstanding (including any tendered shares but excluding
         any shares held in the treasury of the Company) on the Purchase Date,
         the Conversion Price shall be reduced so that the same shall equal the
         price determined by multiplying such Conversion Price in effect
         immediately prior to the effectiveness of the Conversion Price
         reduction contemplated by this paragraph (e) by a fraction of which the
         numerator shall be the current market price per share (determined as
         provided in paragraph (f) of this Section 5.06) of the Common Stock on
         the Purchase Date less the amount of such Excess Payments and such cash
         distributions, if any, applicable to one share (based on the pro rata
         portion of the aggregate amount of such Excess Payments and such cash
         distributions, divided by the shares of Common Stock outstanding on the
         Purchase Date) of Common Stock and the denominator shall be such
         current market price per share (determined as provided in paragraph (f)
         of this Section 5.06) of the Common Stock on the Purchase Date, such
         reduction to become effective immediately prior to the opening of
         business on the day following the Purchase Date.

                  (f) The current market price per share of Common Stock on any
         date shall be deemed to be the average of the Daily Market Prices for
         the shorter of (i) ten consecutive business days ending on the last
         full trading day on the