<PAGE>

                                  Exhibit 4.1

================================================================================



                                   INDENTURE

                                    between

                             CURAGEN CORPORATION,

                                  the Company

                                      and

                           THE CHASE MANHATTAN BANK,

                                  as Trustee


              6.00% CONVERTIBLE SUBORDINATED DEBENTURES DUE 2007



                         Dated as of February 2, 2000


================================================================================
<PAGE>

                            CROSS-REFERENCE TABLE*

<TABLE>
<CAPTION>
Trust Indenture                                                                           Indenture
Act Section                                                                                Section
-----------                                                                                -------
<S>                                                                                       <C>
310(a)(1)........................................................................              5.11
   (a)(2)........................................................................              5.11
   (a)(3)........................................................................               n/a
   (a)(4)........................................................................               n/a
   (a)(5)........................................................................              5.11
   (b)...........................................................................         5.3; 5.11
   (c)...........................................................................               n/a

311(a)...........................................................................              5.12
   (b)...........................................................................              5.12
   (c)...........................................................................               n/a

312(a)...........................................................................              2.10
   (b)...........................................................................              14.3
   (c)...........................................................................              14.3

313(a)...........................................................................               5.7
   (b)(1)........................................................................               n/a
   (b)(2)........................................................................               5.7
   (c)...........................................................................         5.7; 14.2
   (d)...........................................................................               5.7

314(a)(1), (2), (3)..............................................................         9.6; 14.6
   (a)(4)........................................................................    9.6; 9.7; 14.6
   (b)...........................................................................               n/a
   (c)(1)........................................................................              14.5
   (c)(2)........................................................................              14.5
   (c)(3)........................................................................               n/a
   (d)...........................................................................               n/a
   (e)...........................................................................              14.6
   (f)...........................................................................               n/a

315(a)...........................................................................               5.1(a)
   (b)...........................................................................         5.6; 14.2
   (c)...........................................................................               5.1(b)
   (d)...........................................................................               5.1(c)
   (e)...........................................................................              4.14

316(a)(last sentence)............................................................              2.13
   (a)(1)(A).....................................................................               4.5
   (a)(1)(B).....................................................................               4.4
   (a)(2)........................................................................               n/a
</TABLE>

                                       i
<PAGE>

<TABLE>
<S>                                                                                            <C>
   (b)...........................................................................               4.7
   (c)...........................................................................               7.4

317(a)(1)........................................................................               4.8
   (a)(2)........................................................................               4.9
   (b)...........................................................................               2.5

318(a)...........................................................................              14.1
   (b)...........................................................................               n/a
   (c)...........................................................................              14.1
</TABLE>

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

"n/a" means not applicable.

*This Cross-Reference Table shall not, for any purpose, be deemed to be a part
of the Indenture.

                                      ii
<PAGE>

<TABLE>
<CAPTION>
                                                             ARTICLE 1

                                            DEFINITIONS AND INCORPORATION BY REFERENCE
<S>                                                                                                             <C>
Section 1.1       Definitions...................................................................................  1
Section 1.2       Incorporation by Reference of Trust Indenture Act............................................. 13
Section 1.3       Rules of Construction......................................................................... 14

                                                             ARTICLE 2

                                                          THE SECURITIES

Section 2.1       Title and Terms............................................................................... 14
Section 2.2       Form of Securities............................................................................ 15
Section 2.3       Legends....................................................................................... 17
Section 2.4       Execution, Authentication, Delivery and Dating................................................ 22
Section 2.5       Registrar and Paying Agent.................................................................... 23
Section 2.6       Paying Agent to Hold Assets in Trust.......................................................... 24
Section 2.7       General Provisions Relating to Transfer and Exchange.......................................... 24
Section 2.8       Book-Entry Provisions for the Global Securities............................................... 25
Section 2.9       Special Transfer Provisions................................................................... 27
Section 2.10      Holder Lists.................................................................................. 29
Section 2.11      Persons Deemed Owners......................................................................... 29
Section 2.12      Mutilated, Destroyed, Lost or Stolen Securities............................................... 29
Section 2.13      Treasury Securities........................................................................... 30
Section 2.14      Temporary Securities.......................................................................... 30
Section 2.15      Cancellation.................................................................................. 31
Section 2.16      CUSIP Numbers................................................................................. 31
Section 2.17      Defaulted Interest............................................................................ 31

                                                             ARTICLE 3

                                                    SATISFACTION AND DISCHARGE

Section 3.1       Satisfaction and Discharge of Indenture....................................................... 32
Section 3.2       Deposited Monies to be Held in Trust.......................................................... 33
Section 3.3       Return of Unclaimed Monies.................................................................... 33

                                                             ARTICLE 4

                                                       DEFAULTS AND REMEDIES

Section 4.1       Events of Default............................................................................. 34
Section 4.2       Acceleration of Maturity; Rescission and Annulment............................................ 35
Section 4.3       Other Remedies................................................................................ 36
Section 4.4       Waiver of Past Defaults....................................................................... 36
</TABLE>

                                      iii
<PAGE>

<TABLE>
<S>                                                                                                              <C>
Section 4.5       Control by Majority........................................................................... 37
Section 4.6       Limitation on Suit............................................................................ 37
Section 4.7       Unconditional Rights of Holders to Receive Payment and to Convert............................. 38
Section 4.8       Collection of Indebtedness and Suits for Enforcement by the Trustee........................... 38
Section 4.9       Trustee May File Proofs of Claim.............................................................. 39
Section 4.10      Restoration of Rights and Remedies............................................................ 39
Section 4.11      Rights and Remedies Cumulative................................................................ 39
Section 4.12      Delay or Omission Not Waiver.................................................................. 40
Section 4.13      Application of Money Collected................................................................ 40
Section 4.14      Undertaking for Costs......................................................................... 40
Section 4.15      Waiver of Stay or Extension Laws.............................................................. 41

                                                               ARTICLE 5

                                                              THE TRUSTEE

Section 5.1       Certain Duties and Responsibilities........................................................... 41
Section 5.2       Certain Rights of Trustee..................................................................... 43
Section 5.3       Individual Rights of Trustee.................................................................. 43
Section 5.4       Money Held in Trust........................................................................... 44
Section 5.5       Trustee's Disclaimer.......................................................................... 44
Section 5.6       Notice of Defaults............................................................................ 44
Section 5.7       Reports by Trustee to Holders................................................................. 44
Section 5.8       Compensation and Indemnification.............................................................. 44
Section 5.9       Replacement of Trustee........................................................................ 45
Section 5.10      Successor Trustee by Merger, Etc.............................................................. 46
Section 5.11      Corporate Trustee Required; Eligibility....................................................... 46
Section 5.12      Collection of Claims Against the Company...................................................... 46

                                                             ARTICLE 6

                                       CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE

Section 6.1       Company May Consolidate, Etc., Only on Certain Terms.......................................... 47
Section 6.2       Successor Corporation Substituted............................................................. 47

                                                             ARTICLE 7

                                                AMENDMENTS, SUPPLEMENTS AND WAIVERS

Section 7.1       Without Consent of Holders of Securities...................................................... 48
Section 7.2       With Consent of Holders of Securities......................................................... 49
Section 7.3       Compliance with Trust Indenture Act........................................................... 50
Section 7.4       Revocation of Consents and Effect of Consents or Votes........................................ 50
Section 7.5       Notation on or Exchange of Securities......................................................... 50
Section 7.6       Trustee to Sign Amendment, Etc................................................................ 51
</TABLE>

                                      iv
<PAGE>

<TABLE>
<CAPTION>
                                                             ARTICLE 8

                                                 MEETING OF HOLDERS OF SECURITIES
<S>                                                                                                               <C>
Section 8.1       Purposes for Which Meetings May Be Called.....................................................  51
Section 8.2       Call Notice and Place of Meetings.............................................................  51
Section 8.3       Persons Entitled to Vote at Meetings..........................................................  52
Section 8.4       Quorum; Action................................................................................  52
Section 8.5       Determination of Voting Rights; Conduct and Adjournment of Meetings...........................  53
Section 8.6       Counting Votes and Recording Action of Meetings...............................................  53

                                                             ARTICLE 9

                                                             COVENANTS

Section 9.1       Payment of Principal, Premium and Interest....................................................  54
Section 9.2       Maintenance of Offices or Agencies............................................................  54
Section 9.3       Corporate Existence...........................................................................  55
Section 9.4       Maintenance of Properties.....................................................................  55
Section 9.5       Payment of Taxes and Other Claims.............................................................  55
Section 9.6       Reports.......................................................................................  55
Section 9.7       Compliance Certificate........................................................................  56
Section 9.8       Resale of Certain Securities..................................................................  56

                                                            ARTICLE 10

                                                     REDEMPTION OF SECURITIES

Section 10.1      Provisional Redemption........................................................................  56
Section 10.2      Non-provisional Redemption....................................................................  58
Section 10.3      Notice to Trustee.............................................................................  59
Section 10.4      Selection of Securities to Be Redeemed........................................................  59
Section 10.5      Notice of Redemption..........................................................................  59
Section 10.6      Effect of Notice of Redemption................................................................  60
Section 10.7      Deposit of Redemption Price...................................................................  61
Section 10.8      Securities Redeemed in Part...................................................................  61
Section 11.1      Repurchase Right..............................................................................  61
Section 11.2      Conditions to the Company's Election to Pay the Repurchase Price or an Interest Make-Whole
                  Payment in Common Stock.......................................................................  62
Section 11.3      Notices; Method of Exercising Repurchase Right, Etc...........................................  63

                                                            ARTICLE 12

                                                     CONVERSION OF SECURITIES

Section 12.1      Conversion Right and Conversion Price.........................................................  66
Section 12.2      Exercise of Conversion Right..................................................................  66
</TABLE>

                                       v
<PAGE>

<TABLE>
<S>                                                                                                               <C>
Section 12.3      Fractions of Shares...........................................................................  67
Section 12.4      Adjustment of Conversion Price................................................................  68
Section 12.5      Notice of Adjustments of Conversion Price.....................................................  77
Section 12.6      Notice Prior to Certain Action................................................................  77
Section 12.7      Company to Reserve Common Stock...............................................................  78
Section 12.8      Section Taxes on Conversions..................................................................  78
Section 12.9      Covenant as to Common Stock...................................................................  78
Section 12.10     Cancellation of Converted Securities..........................................................  79
Section 12.11     Effect of Reclassification, Consolidation, Merger or Sale.....................................  79
Section 12.12     Responsibility of Trustee for Conversion Provisions...........................................  80

                                                            ARTICLE 13

                                                           SUBORDINATION

Section 13.1      Securities Subordinated to Senior Debt........................................................  81
Section 13.2      Subrogation...................................................................................  83
Section 13.3      Obligation of the Company is Absolute and Unconditional.......................................  83
Section 13.4      Maturity of or Default on Senior Debt.........................................................  83
Section 13.5      Payments on Securities Permitted..............................................................  84
Section 13.6      Effectuation of Subordination by Trustee......................................................  84
Section 13.7      Knowledge of Trustee..........................................................................  84
Section 13.8      Trustee's Relation to Senior Debt.............................................................  85
Section 13.9      Rights of Holders of Senior Debt Not Impaired.................................................  85
Section 13.10     Modification of Terms of Senior Debt..........................................................  85
Section 13.11     Certain Conversions Not Deemed Payment........................................................  85

                                                            ARTICLE 14

                                              OTHER PROVISIONS OF GENERAL APPLICATION

Section 14.1      Trust Indenture Act Controls..................................................................  86
Section 14.2      Notices.......................................................................................  86
Section 14.3      Communication by Holders with Other Holders...................................................  87
Section 14.4      Acts of Holders of Securities.................................................................  87
Section 14.5      Certificate and Opinion as to Conditions Precedent............................................  88
Section 14.6      Statements Required in Certificate or Opinion.................................................  89
Section 14.7      Effect of Headings and Table of Contents......................................................  89
Section 14.8      Successors and Assigns........................................................................  89
Section 14.9      Separability Clause...........................................................................  89
Section 14.10     Benefits of Indenture.........................................................................  90
Section 14.11     Section Governing Law.........................................................................  90
Section 14.12     Counterparts..................................................................................  90
Section 14.13     Legal Holidays................................................................................  90
Section 14.14     Recourse Against Others.......................................................................  90
</TABLE>

                                      vi
<PAGE>

<TABLE>
<S>                                                                                                            <C>
EXHIBITS

EXHIBIT A:          Form of Security........................................................................... A-1

EXHIBIT B:          Form of Investment Representation Letter................................................... B-1
</TABLE>

                                      vii
<PAGE>

          INDENTURE, dated as of February 2, 2000, between CURAGEN CORPORATION,
a corporation duly organized and existing under the laws of the State of
Delaware, having its principal office at 555 Long Wharf Drive, 11/th/ Floor, New
Haven, Connecticut 06511 (the "Company"), and THE CHASE MANHATTAN BANK, a New
York banking corporation, as Trustee (the "Trustee"), having its principal
corporate trust office at 450 West 33/rd/ Street, 15th Floor, New York, NY
10001.

                            RECITALS OF THE COMPANY

          The Company has duly authorized the creation of an issue of its 6.00%
Convertible Subordinated Debentures due 2007 (herein called the "Securities") of
substantially the tenor and amount hereinafter set forth, and to provide
therefor the Company has duly authorized the execution and delivery of this
Indenture.

          All things necessary to make the Securities, when the Securities are
executed by the Company and authenticated and delivered hereunder and duly
issued by the Company, the valid obligations of the Company, and to make this
Indenture a valid agreement of the Company, in accordance with their and its
terms, have been done.

          NOW, THEREFORE, THIS INDENTURE WITNESSETH:

          For and in consideration of the premises and the purchase of the
Securities by the Holders thereof, it is mutually covenanted and agreed, for the
equal and proportionate benefit of all Holders of the Securities, as follows:

                                   ARTICLE 1

                  DEFINITIONS AND INCORPORATION BY REFERENCE

  Section 1.1  Definitions.

          For all purposes of this Indenture and the Securities, the following
terms are defined as follows:

          "Act", when used with respect to any Holder of a Security, has the
     meaning specified in Section 14.4(a).

          "Additional Amounts" means all amounts, if any, payable pursuant to
     Section 3 of the Registration Rights Agreement.

          "Adjusted Interest Rate" means, with respect to any Reset Transaction,
     the rate per annum that is the arithmetic average of the rates quoted by
     two Reference Dealers selected by the Company or its successor as the rate
     at which interest on the Securities should accrue so that the fair market
     value, expressed in dollars, of a Security immediately after the later of:

               (1) the public announcement of such Reset Transaction; or

                                       1
<PAGE>

               (2) the public announcement of a change in dividend policy in
          connection with such Reset Transaction;

     will most closely equal the average Trading Price of a Security for the 20
     Trading Days preceding the date of public announcement of such Reset
     Transaction; provided that the Adjusted Interest Rate shall not be less
     than 6.00% per annum.

          "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 the purposes of this definition,
     "control", when used with respect to any specified Person, means the power
     to direct the management and policies of such Person, directly or
     indirectly, whether through the ownership of voting securities, by contract
     or otherwise; and the terms "controlling" and "controlled" have meanings
     correlative to the foregoing.

          "Agent Member" has the meaning stated in Section 2.8.

          "Applicable Procedures" has the meaning stated in Section 2.9(b).

          "Bankruptcy Law" means Title 11 of the U.S. Code or any similar
     federal or state law for the relief of debtors.

          "Board of Directors" means either the board of directors of the
     Company or any committee of that board empowered to act for it with respect
     to this Indenture.

          "Board Resolution" means a resolution duly adopted by the Board of
     Directors, a copy of which, certified by the Secretary or an Assistant
     Secretary of the Company to be in full force and effect on the date of such
     certification, shall have been delivered to the Trustee.

          "Business Day", when used with respect to any Place of Payment or
     Place of Conversion, means each Monday, Tuesday, Wednesday, Thursday and
     Friday which is not a day on which banking institutions in that Place of
     Payment or Place of Conversion, as the case may be, are authorized or
     obligated by law to close.

          "Capital Lease" means all obligations and liabilities (contingent or
     otherwise) in respect of leases of such Person required, in conformity with
     generally accepted accounting principles, to be accounted for as
     capitalized lease obligations on the balance sheet of such Person.

          "Change of Control" means the occurrence of any of the following after
     the original issuance of the Securities:

               (1) the acquisition by any Person of beneficial ownership,
          directly or indirectly, through a purchase, merger or other
          acquisition transaction or series of transactions, of shares of
          capital stock of the Company entitling such person to exercise 50% or
          more of the total voting power of all shares of capital stock of the
          Company entitled to vote generally in elections of directors, other
          than any such

                                       2
<PAGE>

          acquisition by the Company, any subsidiary of the Company or any
          employee benefit plan of the Company; or

               (2) any consolidation or merger of the Company with or into any
          other Person, any merger of another Person into the Company, or any
          conveyance, transfer, sale, lease or other disposition of all or
          substantially all of the properties and assets of the Company to
          another Person, other than (a) any such transaction (x) that does not
          result in any reclassification, conversion, exchange or cancellation
          of outstanding shares of capital stock of the Company and (y) pursuant
          to which holders of capital stock of the Company immediately prior to
          such transaction have the entitlement to exercise, directly or
          indirectly, 50% or more of the total voting power of all shares of
          capital stock of the Company entitled to vote generally in the
          election of directors of the continuing or surviving person
          immediately after such transaction and (b) any merger which is
          effected solely to change the jurisdiction of incorporation of the
          Company and results in a reclassification, conversion or exchange of
          outstanding shares of Common Stock solely into shares of common stock
          of the surviving entity;

     provided, however, that a Change of Control shall not be deemed to have
     occurred if the Trading Price per share of the Common Stock for any five
     Trading Days within the period of 10 consecutive Trading Days ending
     immediately after the later of the Change of Control or the public
     announcement of the Change of Control, in the case of a Change of Control
     under clause (1) above, or the period of 10 consecutive Trading Days ending
     immediately before the Change of Control, in the case of a Change of
     Control under clause (2) above, shall equal or exceed 110% of the
     Conversion Price of the Securities in effect on each such Trading Day.
     Beneficial ownership shall be determined in accordance with Rule 13d-3
     promulgated by the SEC under the Exchange Act.  As used in this definition,
     the term "Person" shall include any syndicate or group which would be
     deemed to be a "person" under Section 13(d)(3) of the Exchange Act.

          "Clearstream" means Clearstream Banking, societe anonyme (formerly
     Cedelbank).

          "Closing Date" means February 2, 2000 or such later date on which the
     Securities may be delivered pursuant to the Purchase Agreement.

          "Common Stock" means any stock of any class of the Company which has
     no preference in respect of dividends or of amounts payable in the event of
     any voluntary or involuntary liquidation, dissolution or winding up of the
     Company and which is not subject to redemption by the Company.  However,
     subject to the provisions of Section 12.11, shares issuable on conversion
     of Securities shall include only shares of the class designated as Common
     Stock, par value $0.01 per share, of the Company at the date of this
     Indenture or shares of any class or classes resulting from any
     reclassification or reclassifications thereof and which have no preference
     in respect of dividends or of amounts payable in the event of any voluntary
     or involuntary liquidation, dissolution or winding up of the Company and
     which are not subject to redemption by the Company; provided, however,
     that if at any time there shall be more than one such resulting class,

                                       3
<PAGE>

     the shares of each such class then so issuable shall be substantially in
     the proportion which the total number of shares of such class resulting
     from all such reclassifications bears to the total number of shares of all
     such classes resulting from all such reclassifications.

          "Company" means the corporation named as the "Company" in the first
     paragraph of this instrument until a successor Person shall have become
     such pursuant to the applicable provisions of this Indenture, and
     thereafter "Company" shall mean such successor Person.

          "Company Notice" has the meaning specified in Section 11.3.

          "Company Order" means a written order signed in the name of the
     Company by both (1) the Chairman of the Board, the Chief Executive Officer,
     the President or a Vice President and (2) so long as not the same as the
     officer signing pursuant to clause (1), the Chief Financial Officer, the
     Treasurer or the Secretary of the Company, and delivered to the Trustee.

          "Conversion Agent" means any Person authorized by the Company to
     convert Securities in accordance with Article 12.

          "Conversion Price" has the meaning specified in Section 12.1.

          "Corporate Trust Office" means for purposes of presentation or
     surrender of Securities for payment, registration, transfer, exchange or
     conversion or for service of notices or demands upon the Company or for any
     other purpose of this Indenture, the office of the Trustee located in The
     City of New York at which at any particular time its corporate trust
     business shall be administered (which at the date of this Indenture is
     located at 450 West 33/rd/ Street, 15th Floor, New York, NY 10001).

          "corporation" means corporations, associations, limited liability
     companies, companies and business trusts.

          "Current Market Price" has the meaning set forth in Section 12.4(g).

          "Current Market Value" has the meaning set forth in Section 10.1(a).

          "Custodian" means any receiver, trustee, assignee, liquidator,
     sequestrator or similar official under any Bankruptcy Law.

          "Default" means an event which is, or after notice or lapse of time or
     both would be, an Event of Default.

          "Defaulted Interest" has the meaning specified in Section 2.17.

          "Depositary" means The Depository Trust Company, its nominees and
     their respective successors.

                                       4
<PAGE>

          "Depositary Securities Certification" has the meaning specified in
     Section 2.2(b).

          "Designated Senior Debt" means Senior Debt of the Company which, at
     the date of determination, (i) has an aggregate amount outstanding of, or
     under which, at the date of determination, the holders thereof are
     committed to lend up to, at least (a) $25 million, in the case of any
     Senior Debt other than a Capital Lease and Purchase Money Debt or (b) $10
     million, in the case of a Capital Lease and Purchase Money Debt; and (ii)
     is specifically designated in the instrument, agreement or other document
     evidencing or governing that Senior Debt as "Designated Senior Debt" for
     purposes of this Indenture (provided, however, 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).

          "Dividend Yield" on any security for any period means the dividends
     paid or proposed to be paid pursuant to an announced dividend policy on
     such security for such period divided by, if with respect to dividends paid
     on such security, the average Trading Price of such security during such
     period and, if with respect to dividends proposed to be paid on such
     security, the Trading Price of such security on the effective date of the
     related Reset Transaction.

          "Dollar," "U.S. Dollar" or "U.S. $" means a dollar or other equivalent
     unit in such coin or currency of the United States as at the time shall be
     legal tender for the payment of public and private debts.

          "Euroclear" means Morgan Guaranty Trust Company of New York, Brussels
     Office, as operator of the Euroclear System.

          "Event of Default" has the meaning specified in Section 4.1.

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

          "Expiration Time" has the meaning specified in Section 12.4(f).

          "fair market value" has the meaning set forth in Section 12.4(g).

          "Global Security" has the meaning specified in Section 2.2(b).

          "guarantee" means any obligation, contingent or otherwise, of any
     Person, directly or indirectly guaranteeing any Indebtedness of any other
     Person and any obligation, direct or indirect, contingent or otherwise, of
     such Person:

               (1) to purchase or pay (or advance or supply funds for the
          purchase or payment of) such Indebtedness of such other Person
          (whether arising by virtue of partnership arrangements, or by
          agreement to keep-well, to purchase assets, goods, securities or
          services, to take-or-pay, or maintain financial statement conditions
          or otherwise); or

                                       5
<PAGE>

               (2) entered into for purposes of assuring in any other manner the
          obligee of such Indebtedness of the payment thereof or to protect such
          obligee against loss in respect thereof (in whole or in part);

     provided, however, that the term "guarantee" will not include endorsements
     for collection or deposit in the ordinary course of business.  The term
     "guarantee" used as a verb has a corresponding meaning.

          "Holder", when used with respect to any Security, including any Global
     Security, means the Person in whose name the Security is registered in the
     Register.

          "Indebtedness", when used with respect to any Person, and without
     duplication means:

               (1) all indebtedness, obligations and other liabilities
          (contingent or otherwise) of such Person for borrowed money (including
          obligations of the Company in respect of overdrafts, foreign exchange
          contracts, currency exchange agreements, Interest Rate Protection
          Agreements, and any loans or advances from banks, whether or not
          evidenced by notes or similar instruments) or evidenced by bonds,
          debentures, notes or other instruments for the payment of money, or
          Purchase Money Debt, or incurred in connection with the acquisition of
          any services (whether or not the recourse of the lender is to the
          whole of the assets of such Person or to only a portion thereof),
          other than any account payable or other accrued current liability or
          obligation to trade creditors incurred in the ordinary course of
          business in connection with the obtaining of such services;

               (2) all reimbursement obligations and other liabilities
          (contingent or otherwise) of such Person with respect to letters of
          credit, bank guarantees, bankers' acceptances, surety bonds,
          performance bonds or other guaranty of contractual performance;

               (3) all obligations and liabilities (contingent or otherwise) in
          respect of (a) Capital Leases; and (b) any lease or related documents
          (including a purchase agreement) in connection with the lease of real
          property which provides that such Person is contractually obligated to
          purchase or cause a third party to purchase the leased property and
          thereby guarantee a minimum residual value of the leased property to
          the landlord and the obligations of such Person under such lease or
          related document to purchase or to cause a third party to purchase the
          leased property;

               (4) all obligations of such Person (contingent or otherwise) with
          respect to an interest rate or other swap, cap or collar agreement or
          other similar instrument or agreement or foreign currency hedge,
          exchange, purchase or similar instrument or agreement;

               (5) all direct or indirect guaranties or similar agreements by
          such Person in respect of, and obligations or liabilities (contingent
          or otherwise) of such Person to purchase or otherwise acquire or
          otherwise assure a creditor

                                       6
<PAGE>

          against loss in respect of, indebtedness, obligations or liabilities
          of another Person of the kind described in clauses (1) through (4);

               (6) any indebtedness or other obligations described in clauses
          (1) through (4) secured by any mortgage, pledge, lien or other
          encumbrance existing on property which is owned or held by such
          Person, regardless of whether the indebtedness or other obligation
          secured thereby shall have been assumed by such Person; and

               (7) any and all deferrals, renewals, extensions and refundings
          of, or amendments, modifications or supplements to, any indebtedness,
          obligation or liability of the kind described in clauses (1) through
          (6).

          "Indenture" means this instrument as originally executed or as it may
     from time to time be supplemented or amended by one or more indentures
     supplemental hereto entered into pursuant to the applicable provisions
     hereof.

          "Initial Purchasers" mean Lehman Brothers Inc., Morgan Stanley & Co.
     Incorporated and Dain Rauscher Incorporated.

          "Institutional Accredited Investor" means an institution that is an
     "accredited investor" as that term is defined in Rule 501(a) (1), (2), (3)
     or (7) under the Securities Act.

          "Interest Make-Whole Payment" has the meaning specified in Section
     10.1(b).

          "Interest Make-Whole Period" has the meaning specified in Section
     10.1(b).

          "Interest Payment Date" means each of August 2 and February 2;
     provided, however, that if any such date is not a Business Day, the
     Interest Payment Date shall be the next succeeding Business Day.

          "Interest Rate" means, (a) if a Reset Transaction has not occurred,
     6.00% per annum, or (b) following the occurrence of a Reset Transaction,
     the Adjusted Interest Rate related to such Reset Transaction to, but not
     including the effective date of any succeeding Reset Transaction.

          "Interest Rate Protection Agreement" means, with respect to any
     Person, any interest rate swap agreement, interest rate cap or collar
     agreement or other financial agreement or arrangement designed to protect
     such person against fluctuations in interest rates, as in effect from time
     to time.

          "Internal Revenue Code" means the Internal Revenue Code of 1986, as
     amended.

          "Investment Representation Letter" has the meaning specified in
     Section 2.2(d).

          "Maturity" means the date on which the principal of such Security
     becomes due and payable as therein or herein provided, whether at the
     Stated Maturity or by

                                       7
<PAGE>

     acceleration, conversion, call for redemption, exercise of a Repurchase
     Right or otherwise.

          "Nasdaq National Market" means the National Association of Securities
     Dealers Automated Quotation National Market or any successor national
     securities exchange or automated over-the-counter trading market in the
     United States.

          "Non-Electing Share" has the meaning specified in Section 12.11.

          "Non-institutional Accredited Investor" means a Person that is an
     "accredited investor" as that term is defined in Rule 501(a) (4), (5) or
     (6) under the Securities Act.

          "Officer" of the Company means the Chairman of the Board, the Chief
     Executive Officer, the President, the Chief Financial Officer, the
     Treasurer, any Vice President or the Secretary of the Company.

          "Officers' Certificate" means a certificate signed by both (1) the
     Chairman of the Board, the Chief Executive Officer, the President or a Vice
     President and (2) so long as not the same as the officer signing pursuant
     to clause (1), the Chief Financial Officer, the Treasurer or the Secretary
     of the Company, and delivered to the Trustee.

          "Opinion of Counsel" means a written opinion of counsel, who may be
     counsel to the Company (and may include directors or employees of the
     Company) and who is acceptable to the Trustee, which acceptance shall not
     be unreasonably withheld.

          "Outstanding", when used with respect to Securities, means, as of the
     date of determination, all Securities theretofore authenticated and
     delivered under this Indenture, except Securities:

               (1) previously canceled by the Trustee or delivered to the
          Trustee for cancellation;

               (2) for the payment or redemption of which money in the necessary
          amount has been previously deposited with the Trustee or any Paying
          Agent (other than the Company) in trust or set aside and segregated in
          trust by the Company (if the Company shall act as its own Paying
          Agent) for the Holders of such Securities; provided, however, that if
          such Securities are to be redeemed, notice of such redemption has been
          duly given pursuant to this Indenture; and

               (3) which have been paid in exchange for or in lieu of other
          Securities which have been authenticated and delivered pursuant to
          this Indenture, other than any such Securities in respect of which
          there shall have been presented to the Trustee proof satisfactory to
          it that such Securities are held by a bona fide purchaser in whose
          hands such Securities are valid obligations of the Company.

          "Owner Securities Certification" has the meaning specified in Section
     2.2(b).

          "Paying Agent" has the meaning specified in Section 2.5.

                                       8
<PAGE>

          "Payment Blockage Notice" has the meaning specified in Section
     13.1(d).

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

          "Physical Securities" has the meaning specified in Section 2.2(d).

          "Place of Conversion" means any city in which any Conversion Agent is
     located.

          "Place of Payment" means any city in which any Paying Agent is
     located.

          "Predecessor Security" of any particular Security means every previous
     Security evidencing all or a portion of the same debt as that evidenced by
     such particular Security; and, for the purposes of this definition, any
     Security authenticated and delivered under Section 2.12 in exchange for or
     in lieu of a mutilated, destroyed, lost or stolen Security shall be deemed
     to evidence the same debt as the mutilated, destroyed, lost or stolen
     Security.

          "Present Value" has the meaning specified in Section 10.1(b).

          "Purchase Agreement" means the Purchase Agreement, dated January 27,
     2000, between the Company and the Initial Purchasers.

          "Purchase Money Debt" means all indebtedness, obligations and other
     liabilities (contingent or otherwise) incurred in connection with the
     acquisition of any property or assets (whether or not the recourse of the
     lender is to the whole of the assets of the borrower or to only a portion
     thereof), other than any account payable or other accrued current liability
     or obligation to trade creditors incurred in the ordinary course of
     business in connection with the obtaining of materials.

          "QIB" means a "qualified institutional buyer" as defined in Rule 144A.

          "Record Date" means either a Regular Record Date or a Special Record
     Date, as the case may be; provided that, for purposes of Section 12.4,
     Record Date has the meaning specified in 12.4(g).

          "Redemption Date", when used with respect to any Security to be
     redeemed, means the date fixed for such redemption by or pursuant to this
     Indenture.

          "Redemption Price", when used with respect to any Security to be
     redeemed, means the price at which such Security is to be redeemed pursuant
     to this Indenture.

          "Reference Dealer" means a dealer engaged in the trading of
     convertible securities.

          "Reference Period" has the meaning set forth in Section 12.4(d).

                                       9
<PAGE>

          "Register" has the meaning specified in Section 2.5.

          "Registrar" has the meaning specified in Section 2.5.

          "Registration Rights Agreement" means the Resale Registration Rights
     Agreement dated as of February 2, 2000, between the Company and the Initial
     Purchasers.

          "Regular Record Date" for the interest on the Securities (including
     Additional Amounts, if any) payable means the July 19 (whether or  not a
     Business Day) next preceding an Interest Payment Date on August 2 and the
     January 19 (whether or not a Business Day) next preceding an Interest
     Payment Date on February 2.

          "Regulation S" means Regulation S under the Securities Act.

          "Repurchase Date" has the meaning specified in Section 11.1.

          "Repurchase Price" has the meaning specified in Section 11.1.

          "Repurchase Right" has the meaning specified in Section 11.1.

          "Reset Transaction" means a merger, consolidation or statutory share
     exchange to which the entity that is the Company of the shares of common
     stock into which the Securities are then convertible is a party, a sale of
     all or substantially all the assets of that entity, a recapitalization of
     those shares of common stock or a distribution described in Section
     12.4(d), after the effective date of which transaction or distribution the
     Securities would be convertible into:

               (1) shares of an entity the common stock of which had a Dividend
          Yield for the four fiscal quarters of such entity immediately
          preceding the public announcement of such transaction or distribution
          that was more than 2.5% higher then the Dividend Yield on the Common
          Stock (or other common stock then issuable upon conversion of the
          Securities) for the four fiscal quarters preceding the public
          announcement of such transaction or distribution; or

               (2) shares of an entity that announces a dividend policy prior to
          the effective date of such transaction or distribution which policy,
          if implemented, would result in a Dividend Yield on such entity's
          common stock for the next four fiscal quarters that would result in
          such a 2.5% basis point increase.

          "Responsible Officer", when used with respect to the Trustee, means
     any officer of the Trustee, including any vice president, assistant vice
     president, secretary, assistant secretary, the treasurer, any assistant
     treasurer, the managing director, any trust officer, or any other officer
     of the Trustee customarily performing functions similar to those performed
     by any of the above designated officers and also means, with respect to a
     particular corporate trust matter, any other officer to whom such matter is
     referred because of such officer's knowledge of and familiarity with the
     particular subject.

                                       10
<PAGE>

          "Restricted Securities" means the Securities defined as such in
     Section 2.3.

          "Restricted Securities Legend" has the meaning set forth in Section
     2.3(a).

          "Rule 144" means Rule 144 under the Securities Act (including any
     successor rule thereof), as the same may be amended from time to time.

          "Rule 144A" means Rule 144A as promulgated under the Securities Act
     (including any successor rule thereof), as the same may be amended from
     time to time.

          "SEC" means the Securities and Exchange Commission.

          "Securities" has the meaning ascribed to it in the first paragraph
     under the caption "Recitals of the Company".

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

          "Senior Debt" means the principal of, premium, if any, interest
     (including all interest accruing subsequent to the commencement of any
     bankruptcy or similar proceeding, whether or not a claim for post-petition
     interest is allowable as a claim in any such proceeding) and rent payable
     on or termination payment with respect to or in connection with, and all
     fees, costs, expenses and other amounts accrued or due on or in connection
     with, Indebtedness of the Company, whether outstanding on the date of this
     Indenture or thereafter created, incurred, assumed, guaranteed or in effect
     guaranteed by the Company (including all deferrals, renewals, extensions or
     refundings of, or amendments, modifications or supplements to, the
     foregoing), unless in the case of any particular Indebtedness the
     instrument creating or evidencing the same or the assumption or guarantee
     thereof expressly provides that such Indebtedness shall not be senior in
     right of payment to the Securities or expressly provides that such
     Indebtedness is pari passu or junior to the Securities.  Notwithstanding
     the foregoing, the term "Senior Debt" shall include, without limitation,
     all Designated Senior Debt, and shall not include Indebtedness of the
     Company to any Subsidiary.

          "Shelf Registration Statement" has the meaning specified in the
     Registration Rights Agreement.

          "Significant Subsidiary" means any Subsidiary which is a "significant
     subsidiary" within the meaning of Rule 405 under the Securities Act.

          "Special Record Date" for the payment of any Defaulted Interest means
     a date fixed by the Trustee pursuant to Section 2.17.

          "Stated Maturity" means the date specified in any Security as the
     fixed date for the payment of principal on such Security or on which an
     installment of interest (including Additional Amounts, if any) on such
     Security is due and payable.

          "Subsidiary" means a corporation more than 50% of the outstanding
     voting stock of which is owned, directly or indirectly, by the Company or
     by one or more other

                                       11
<PAGE>

     Subsidiaries, or by the Company and one or more other Subsidiaries. For the
     purposes of this definition only, "voting stock" means stock which
     ordinarily has voting power for the election of directors, whether at all
     times or only so long as no senior class of stock has such voting power by
     reason of any contingency.

          "TIA" means the Trust Indenture Act of 1939, as amended (15 U.S. Code
     Section 77aaa-77bbbb), as in effect on the date of this Indenture;
     provided, however, that in the event the TIA is amended after such date,
     "TIA" means, to the extent such amendment is applicable to this Indenture,
     the Trust Indenture Act of 1939, as so amended, or any successor statute.

          "Trading Day" means:

               (1) if the applicable security is listed or admitted for trading
          on the New York Stock Exchange or another national security exchange,
          a day on which the New York Stock Exchange or such other national
          security exchange is open for business;

               (2) if the applicable security is quoted on the Nasdaq National
          Market, a day on which trades may be made thereon; or

               (3) if the applicable security is not so listed, admitted for
          trading or quoted, any day other than a Saturday or Sunday or a day on
          which banking institutions in the State of New York are authorized or
          obligated by law or executive order to close.

          "Trading Price" of a security on any date of determination means:

               (1) the closing sale price (or, if no closing sale price is
          reported, the last reported sale price) of such security (regular day)
          on the New York Stock Exchange on such date;

               (2) if such security is not listed for trading on the New York
          Stock Exchange on any such date, the closing sale price as reported in
          the composite transactions for the principal U.S. securities exchange
          on which such security is so listed;

               (3) if such security is not so listed on a U.S. national or
          regional securities exchange, the closing sale price as reported by
          the NASDAQ National Market;

               (4) if such security is not so reported, the last price quoted by
          Interactive Data Corporation for such security or, if Interactive Data
          Corporation is not quoting such price, a similar quotation service
          selected by the Company;

               (5) if such security is not so quoted, the average of the mid-
          point of the last bid and ask prices for such security from at least
          two dealers recognized as market-makers for such security; or

                                       12
<PAGE>

               (6) if such security is not so quoted, the average of the last
          bid and ask prices for such security from a Reference Dealer.

          "Transfer Agent" means any Person, which may be the Company,
     authorized by the Company to exchange or register the transfer of
     Securities.

          "Trigger Event" has the meaning specified in Section 12.4(d).

          "Trigger Percentage" has the meaning specified in Section 10.1(a).

          "Trustee" means the Person named as the "Trustee" in the first
     paragraph of this instrument until a successor Trustee shall have become
     such pursuant to the applicable provisions of this Indenture, and
     thereafter "Trustee" shall mean such successor Trustee.

          "U.S. Government Obligations" means: (1) direct obligations of the
     United States of America for the payment of which the full faith and credit
     of the United States of America is pledged or (2) obligations of a person
     controlled or supervised by and acting as an agency or instrumentality of
     the United States of America, the payment of which is unconditionally
     guaranteed as a full faith and credit obligation by the United States of
     America and which in either case, are non-callable at the option of the
     Company thereof.

          "Vice President", when used with respect to the Company, means any
     vice president, whether or not designated by a number or a word or words
     added before or after the title "vice president".

  Section 1.2  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 Securities;

          "indenture security holder" means a Holder;

          "indenture to be qualified" means this Indenture;

          "indenture trustee" or "institutional trustee" means the Trustee; and

          "obligor" on the Securities means the Company and any other obligor on
          the indenture securities.

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

                                       13
<PAGE>

  Section 1.3  Rules of Construction.

          For all purposes of this Indenture, except as otherwise expressly
provided or unless the context otherwise requires:

               (1) the terms defined in this Article have the meanings assigned
          to them in this Article and include the plural as well as the
          singular;

               (2) all accounting terms not otherwise defined herein have the
          meanings assigned to them in accordance with accounting principles
          generally accepted in the United States prevailing at the time of any
          relevant computation hereunder; and

               (3) the words "herein", "hereof" and "hereunder" and other words
          of similar import refer to this Indenture as a whole and not to any
          particular Article, Section or other subdivision.

                                   ARTICLE 2

                                THE SECURITIES

  Section 2.1  Title and Terms.

          (a) The Securities shall be known and designated as the "6.00 %
Convertible Subordinated Debentures due 2007" of the Company.  The aggregate
principal amount of Securities which may be authenticated and delivered under
this Indenture is limited to $125,000,000 (or $150,000,000 if the over-allotment
option set forth in Section 2 of the Purchase Agreement is exercised in full),
except for Securities authenticated and delivered upon registration of, transfer
of, or in exchange for, or in lieu of other Securities pursuant to Section 2.7,
2.8, 2.9, 2.12, 7.5, 10.7, 11.1 or 12.2.  The Securities shall be issuable in
denominations of $1,000 or integral multiples thereof.

          (b) The Securities shall mature on February 2, 2007.

          (c) Interest shall accrue from February 2, 2000 at the Interest Rate
until the principal thereof is paid or made available for payment.  Interest
shall be payable semiannually in arrears on February 2 and August 2 in each
year, commencing August 2, 2000.

          (d) Interest on the Securities shall be computed (i) for any full
semi-annual period for which a particular Interest Rate is applicable, on the
basis of a 360-day year of twelve 30-day months and (ii) for any period for
which a particular Interest Rate is applicable shorter than a full semiannual
period for which interest is calculated, on the basis of a 30-day month and, for
such periods of less than a month, the actual number of days elapsed over a 30-
day month.  For purposes of determining the Interest Rate, the Trustee may
assume that a Reset Transaction has not occurred unless the Trustee has received
an Officers' Certificate stating that a Reset Transaction has occurred and
specifying the Adjusted Interest Rate then in effect.

                                       14
<PAGE>

          (e) A Holder of any Security at the close of business on a Regular
Record Date shall be entitled to receive interest (including Additional Amounts,
if any) on such Security on the corresponding Interest Payment Date.  A Holder
of any Security which is converted after the close of business on a Regular
Record Date and prior to the corresponding Interest Payment Date (other than any
Security whose Maturity is prior to such Interest Payment Date) shall be
entitled to receive interest (including Additional Amounts, if any) on the
principal amount of such Security, notwithstanding the conversion of such
Security prior to such Interest Payment Date.  However, any such Holder which
surrenders any such Security for conversion during the period between the close
of business on such Regular Record Date and ending with the opening of business
on the corresponding Interest Payment Date shall be required to pay the Company
an amount equal to the interest (including Additional Amounts, if any) on the
principal amount of such Security so converted, which is payable by the Company
to such Holder on such Interest Payment Date, at the time such Holder surrenders
such Security for conversion.  Notwithstanding the foregoing, any such Holder
which surrenders for conversion any Security which has been called for
redemption by the Company in a notice of redemption given by the Company
pursuant to Section 10.4 shall be entitled to receive (and retain) such interest
(including Additional Amounts, if any) and need not pay the Company an amount
equal to the interest (including Additional Amounts, if any) on the principal
amount of such Security so converted at the time such Holder surrenders such
Security for conversion.

          (f) Principal of, and premium, if any, and interest on, Global
Securities shall be payable to the Depositary in immediately available funds.

          (g) Principal and premium, if any, on Physical Securities shall be
payable at the office or agency of the Company maintained for such purpose,
initially the Corporate Trust Office of the Trustee.  Interest on Physical
Securities will be payable by (i) U.S. Dollar check drawn on a bank in The City
of New York mailed to the address of the Person entitled thereto as such address
shall appear in the Register, or (ii) upon application to the Registrar not
later than the relevant Record Date by a Holder of an aggregate principal amount
of Securities in excess of $5,000,000, wire transfer in immediately available
funds, which application shall remain in effect until the Holder notifies, in
writing, the Registrar to the contrary.

          (h) The Securities shall be redeemable at the option of the Company as
provided in Article 10.

          (i) The Securities shall be repurchaseable by the Company at the
option of Holders as provided in Article 11.

          (j) The Securities shall be convertible at the option of the Holders
as provided in Article 12.

          (k) The Securities shall be subordinated in right of payment to Senior
Debt of the Company as provided in Article 13.

  Section 2.2  Form of Securities.

          (a) Except as otherwise provided pursuant to this Section 2.2, the
Securities are issuable in fully registered form without coupons in
substantially the form of Exhibit A
                          ---------

                                       15
<PAGE>

hereto, with such applicable legends as are provided for in Section 2.3. The
Securities are not issuable in bearer form. The terms and provisions contained
in the form of Security shall constitute, and are hereby expressly made, a 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. Any of the Securities may have such
letters, numbers or other marks of identification and such notations, legends
and endorsements as the officers executing the same may approve (execution
thereof to be conclusive evidence of such approval) and as are not inconsistent
with the provisions of this Indenture, or as may be required to comply with any
law or with any rule or regulation made pursuant thereto or with any rule or
regulation of any securities exchange or automated quotation system on which the
Securities may be listed or designated for issuance, or to conform to usage.

          (b)  The Securities are being offered and sold by the Company pursuant
to the Purchase Agreement.  Securities offered and sold (A) to QIBs in
accordance with Rule 144A and (B) in reliance on Regulation S, each as provided
in the Purchase Agreement, shall be issued initially in the form of one or more
permanent global Securities in fully registered form without interest coupons,
substantially in the form of Exhibit A hereto, with the applicable legends as
                             ---------
provided in Section 2.3 (each a "Global Security" and collectively the "Global
Securities").  Each Global Security shall be duly executed by the Company and
authenticated and delivered by the Trustee, and shall be registered in the name
of the Depositary or its nominee and retained by the Trustee, as Custodian, at
its Corporate Trust Office, for credit to the accounts of the Agent Members
holding the Securities evidenced thereby ( or in the case of Securities held for
purchasers who acquired such Securities in accordance with Regulation S,
registered with the Depositary for credit to the accounts of the Agent Members
then holding such Securities on behalf of Euroclear or Clearstream, as the case
may be).  The aggregate principal amount of the Global Securities may from time
to time be increased or decreased by adjustments made on the records of the
Trustee, as Custodian, and of the Depositary or its nominee, as hereinafter
provided.

          (c) Securities that are issued to Institutional Accredited Investors
that are not QIBs or to Non-Institutional Accredited Investors (each
individually an "Accredited Investor" and collectively the "Accredited
Investors") shall not be issued in the form of Global Securities.  Such
Securities shall only be issued in definitive, fully registered form without
interest coupons, substantially in the form of Exhibit A hereto, with the
                                               ---------
applicable legends as provided in Section 2.3 (individually, a "Physical
Security" and collectively, the "Physical Securities") and only to an Accredited
Investor that has executed and delivered to the Registrar a letter substantially
in the form of Exhibit B hereto (each an "Investment Representation Letter").
               ---------
Physical Securities acquired by QIBs in accordance with Rule 144A or in reliance
on Regulation S may be exchanged for interests in Global Securities pursuant to
Section 2.9(b).  Physical Securities shall be duly executed by the Company and
authenticated and delivered by the Trustee and shall be registered in the name
of the Institutional Accredited Investor purchasing such Security.

                                       16
<PAGE>

          Section 2.3  Legends.

  (a) Restricted Securities Legends.

          Each Security issued hereunder shall, upon issuance, bear the legend
set forth in Section 2.3(a)(i), and each stock certificate representing shares
of Common Stock issued upon conversion of any Security issued hereunder, shall,
upon issuance, bear the legend set forth in Section 2.3(a)(ii)(each such legend,
a "Restricted Securities Legend"), and such legend shall not be removed except
as provided in Section 2.3(a)(iii).  Each Security that bears or is required to
bear the Restricted Securities Legend set forth in Section 2.3(a)(i) (together
with each stock certificate representing shares of Common Stock issued upon
conversion of such Security that bears or is required to bear the Restricted
Securities Legend set forth in Section 2.3(a)(ii), collectively, the "Restricted
Securities") shall be subject to the restrictions on transfer set forth in this
Section 2.3(a) (including the Restricted Securities Legend set forth below), and
the Holder of each such Restricted Security, by such Holder's acceptance
thereof, shall be deemed to have agreed to be bound by all such restrictions on
transfer.

          As used in Section 2.3(a), the term "transfer" encompasses any sale,
pledge, transfer or other disposition whatsoever of any Restricted Security.

          (i) Restricted Securities Legend for Securities.

          Except as provided in Section 2.3(a)(iii), until two years after the
original issuance date of any Security, any certificate evidencing such Security
(and all Securities issued in exchange therefor or substitution thereof, other
than stock certificates representing shares of Common Stock, if any, issued upon
conversion thereof which shall bear the legend set forth in Section 2.3(a)(ii),
if applicable) shall bear a Restricted Securities Legend in substantially the
following form:

   THE SECURITY EVIDENCED BY THIS CERTIFICATE HAS NOT BEEN REGISTERED UNDER THE
   SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE
   SECURITIES LAWS. BY ACQUISITION HEREOF, THE HOLDER:

          (1) REPRESENTS THAT (A) IT IS A "QUALIFIED INSTITUTIONAL BUYER" AS
          DEFINED IN RULE 144A UNDER THE SECURITIES ACT, (B) IT IS A NON-U.S.
          PERSON WHO IS ACQUIRING THIS SECURITY IN AN OFFSHORE TRANSACTION
          MEETING THE REQUIREMENTS OF RULE 903 OR RULE 904 OF REGULATION S UNDER
          THE SECURITIES ACT; OR (C) IT IS AN INSTITUTIONAL "ACCREDITED
          INVESTOR" AS DEFINED IN RULE 501(a)(1), (2), (3) OR (7) UNDER THE
          SECURITIES ACT (AN "INSTITUTIONAL ACCREDITED INVESTOR") THAT IS
          PURCHASING AT LEAST $100,000 IN AGGREGATE PRINCIPAL AMOUNT OF
          DEBENTURES OR AN "ACCREDITED INVESTOR" AS DEFINED IN RULE 501(a)(4),
          (5) or (6) UNDER THE SECURITIES ACT (A "NON-INSTITUTIONAL ACCREDITED
          INVESTOR") THAT IS

                                       17
<PAGE>

          PURCHASING AT LEAST $250,000 IN AGGREGATE PRINCIPAL AMOUNT OF
          DEBENTURES;

          (2) AGREES THAT NEITHER THE SECURITY EVIDENCED HEREBY NOR THE COMMON
          STOCK ISSUABLE UPON CONVERSION OF SUCH SECURITY MAY BE RESOLD, PLEDGED
          OR OTHERWISE TRANSFERRED (X) WITHIN TWO YEARS AFTER THE ORIGINAL
          ISSUANCE OF THE SECURITY EVIDENCED HEREBY OR (Y) BY A HOLDER THAT WAS
          AN AFFILIATE OF THE COMPANY AT ANY TIME DURING THE THREE MONTHS
          PRECEDING THE DATE OF SUCH RESALE, PLEDGE OR TRANSFER, IN EITHER CASE,
          EXCEPT (A) TO THE COMPANY OR ANY SUBSIDIARY THEREOF, (B) TO A
          QUALIFIED INSTITUTIONAL BUYER IN COMPLIANCE WITH RULE 144A UNDER THE
          SECURITIES ACT, (C) TO A NON-U.S. PERSON OUTSIDE OF THE UNITED STATES
          IN COMPLIANCE WITH REGULATIONS S UNDER THE SECURITIES ACT, (D)
          PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT TO
          AN INSTITUTIONAL ACCREDITED INVESTOR THAT IS PURCHASING DEBENTURES IN
          AGGREGATE PRINCIPAL AMOUNT OF AT LEAST $100,000 OR TO A NON-
          INSTITUTIONAL ACCREDITED INVESTOR THAT IS PURCHASING DEBENTURES IN
          AGGREGATE PRINCIPAL AMOUNT OF AT LEAST $250,000, AND THAT, IN EITHER
          CASE, PRIOR TO SUCH TRANSFER, FURNISHES TO THE CHASE MANHATTAN BANK,
          AS TRUSTEE (OR ANY SUCCESSOR TRUSTEE, AS APPLICABLE), A SIGNED LETTER
          CONTAINING CERTAIN REPRESENTATIONS AND WARRANTIES RELATING TO THE
          RESTRICTIONS ON TRANSFER OF THE SECURITY EVIDENCED HEREBY (THE FORM OF
          LETTER CAN BE OBTAINED FROM SUCH TRUSTEE), (E) PURSUANT TO THE
          EXEMPTION FROM REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES
          ACT (IF AVAILABLE) OR (F) PURSUANT TO A REGISTRATION STATEMENT WHICH
          HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT AND WHICH
          CONTINUES TO BE EFFECTIVE AT THE TIME OF SUCH TRANSFER; AND

          (3) AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THE SECURITY
          EVIDENCED HEREBY IS TRANSFERRED (OTHER THAN A TRANSFER PURSUANT TO
          CLAUSE 2(F) ABOVE) A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS
          LEGEND.

   IN CONNECTION WITH ANY TRANSFER OF THE SECURITY EVIDENCED HEREBY WITHIN TWO
   YEARS AFTER THE ORIGINAL ISSUANCE OF SUCH SECURITY (OTHER THAN A TRANSFER

                                       18
<PAGE>

   PURSUANT TO CLAUSE (2)(F) ABOVE), THE HOLDER MUST CHECK THE APPROPRIATE BOX
   SET FORTH ON THE REVERSE HEREOF RELATING TO THE MANNER OF SUCH TRANSFER AND
   SUBMIT THIS CERTIFICATE TO THE TRUSTEE (OR ANY SUCCESSOR TRUSTEE, AS
   APPLICABLE). IF THE PROPOSED TRANSFER IS PURSUANT TO CLAUSE (2)(B), 2(C),
   2(D) OR 2(E) ABOVE, THE HOLDER MUST, PRIOR TO SUCH TRANSFER, FURNISH TO THE
   TRUSTEE (OR ANY SUCCESSOR TRUSTEE, AS APPLICABLE), SUCH 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. THIS LEGEND WILL BE REMOVED UPON THE EARLIER OF THE TRANSFER OF THE
   SECURITY EVIDENCED HEREBY PURSUANT TO CLAUSE (2)(F) ABOVE OR THE EXPIRATION
   OF TWO YEARS FROM THE ORIGINAL ISSUANCE OF THE SECURITY EVIDENCED HEREBY. AS
   USED HEREIN, THE TERMS "UNITED STATES" AND "U.S. PERSON" HAVE THE MEANINGS
   GIVEN TO THEM BY REGULATION S UNDER THE SECURITIES ACT.

          (ii) restricted Securities Legend for Common Stock Issued Upon
   Conversion of the Securities.

          Until two years after the original issuance date of any Security, each
stock certificate representing shares of Common Stock issued upon conversion of
such Security shall bear a Restricted Securities Legend in substantially the
following form:

   THE SECURITY EVIDENCED HEREBY HAS NOT BEEN REGISTERED UNDER THE SECURITIES
   ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS.
   THE HOLDER HEREOF AGREES THAT:

          (1) THE COMMON STOCK EVIDENCED HEREBY MAY NOT BE RESOLD, PLEDGED OR
          OTHERWISE TRANSFERRED (X) WITHIN TWO YEARS AFTER THE ORIGINAL ISSUANCE
          OF THE SECURITY UPON THE CONVERSION OF WHICH THE COMMON STOCK
          EVIDENCED HEREBY WAS ISSUED OR (Y) BY A HOLDER THAT WAS AN AFFILIATE
          OF THE COMPANY AT ANY TIME DURING THE THREE MONTHS PRECEDING THE DATE
          OF SUCH RESALE, PLEDGE OR TRANSFER, IN EITHER CASE, EXCEPT (A) TO THE
          COMPANY OR ANY SUBSIDIARY THEREOF, (B) TO A "QUALIFIED INSTITUTIONAL
          BUYER" AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT, IN COMPLIANCE
          WITH SUCH RULE, (C) TO A NON-U.S. PERSON OUTSIDE OF THE UNITED STATES
          IN COMPLIANCE WITH REGULATIONS S UNDER THE SECURITIES ACT, (D)
          PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES

                                       19
<PAGE>

          ACT TO AN INSTITUTIONAL ACCREDITED INVESTOR (AS DEFINED IN RULE
          501(a)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT) THAT IS
          PURCHASING A NUMBER OF SHARES OF COMMON STOCK AT LEAST EQUAL TO
          $100,000 DIVIDED BY $127.6550 (THE INITIAL CONVERSION PRICE) OR TO A
          NON-INSTITUTIONAL ACCREDITED INVESTOR (AS DEFINED AS DEFINED IN RULE
          501(a)(4), (5) or (6) UNDER THE SECURITIES ACT) THAT IS PURCHASING A
          NUMBER OF SHARES OF COMMON STOCK AT LEAST EQUAL TO $250,000 DIVIDED BY
          $127.6550 (THE INITIAL CONVERSION PRICE) AND THAT, IN EITHER CASE,
          PRIOR TO SUCH TRANSFER, FURNISHES TO AMERICAN STOCK TRANSFER & TRUST
          COMPANY, AS TRANSFER AGENT (OR ANY SUCCESSOR TRANSFER AGENT, AS
          APPLICABLE), A SIGNED LETTER CONTAINING CERTAIN REPRESENTATIONS AND
          WARRANTIES RELATING TO THE RESTRICTIONS ON TRANSFER OF THE SECURITY
          EVIDENCED HEREBY (THE FORM OF LETTER CAN BE OBTAINED FROM SUCH
          TRANSFER AGENT), (E) PURSUANT TO THE EXEMPTION FROM REGISTRATION
          PROVIDED BY RULE 144 UNDER THE SECURITIES ACT (IF AVAILABLE) OR (F)
          PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE
          UNDER THE SECURITIES ACT AND WHICH CONTINUES TO BE EFFECTIVE AT THE
          TIME OF SUCH TRANSFER;

          (2) PRIOR TO ANY SUCH TRANSFER OTHER THAN A TRANSFER PURSUANT TO
          CLAUSE 1(F) ABOVE, IT WILL FURNISH TO SUCH TRANSFER AGENT (OR ANY
          SUCCESSOR TRANSFER AGENT, AS APPLICABLE), SUCH 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; AND

          (3) IT WILL DELIVER TO EACH PERSON TO WHOM THE COMMON STOCK EVIDENCED
          HEREBY IS TRANSFERRED (OTHER THAN A TRANSFER PURSUANT TO A CLAUSE
          (1)(F) ABOVE) A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND.

   THIS LEGEND WILL BE REMOVED UPON THE EARLIER OF THE TRANSFER OF THE COMMON
   STOCK EVIDENCED HEREBY PURSUANT TO CLAUSE (1)(F) ABOVE OR THE EXPIRATION OF
   TWO YEARS FROM THE ORIGINAL ISSUANCE OF THE SECURITY UPON THE CONVERSION OF
   WHICH THE COMMON STOCK EVIDENCED HEREBY WAS ISSUED. AS USED HEREIN, THE TERMS
   "UNITED STATES" AND "U.S. PERSON"

                                       20
<PAGE>

   HAVE THE MEANINGS GIVEN TO THEM BY REGULATION S UNDER THE SECURITIES ACT.

        (iii)  Removal of the Restricted Securities Legends.

        Each Security and each stock certificate representing shares of Common
Stock issued upon conversion of any Security (other than a stock certificate
representing shares of Common Stock issued upon conversion of a Security that
previously has been sold pursuant to a registration statement that has been
declared effective under the Securities Act and which continues to be effective
at the time of such sale shall bear the applicable Restricted Securities Legend
set forth in Section 2.3(a)(i) or 2.3(a)(ii), as the case may be, until the
earlier of:

        (1) the date which is two years after the original issuance date of such
     Security; and

        (2) the date such Security has, or such shares of Common Stock have been
     sold pursuant to a registration statement that has been declared effective
     under the Securities Act (and which continues to be effective at the time
     of such sale).

The Holder must give notice thereof to the Trustee and any transfer agent for
the Common Stock, as applicable.

        Notwithstanding the foregoing, the Restricted Securities Legend may be
removed from any Security or any stock certificate representing shares of Common
Stock issued upon conversion of any Security if there is delivered to the
Company such satisfactory evidence, which may include an opinion of independent
counsel, as may be reasonably required by the Company, that neither such legend
nor the restrictions on transfer set forth therein are required to ensure that
transfers of such Security or shares of Common Stock issued upon conversion of
Securities, as the case may be, will not violate the registration requirements
of the Securities Act.  Upon provision of such satisfactory evidence, at the
written direction of the Company, (i) in the case of a Security, the Trustee
shall authenticate and deliver in exchange for such Security another Security or
Securities having an equal aggregate principal amount that does not bear such
legend or (ii) in the case of a stock certificate representing shares of Common
Stock, the transfer agent for the Common Stock shall authenticate and deliver in
exchange for the stock certificate or stock certificates representing such
shares of Common Stock bearing such legend, one or more new stock certificates
representing a like aggregate number of shares of Common Stock that do not bear
such legend.  If the Restricted Securities Legend has been removed from a
Security or stock certificates representing shares of Common Stock issued upon
conversion of any Security as provided above, no other Security issued in
exchange for all or any part of such Security or stock certificates representing
shares of Common Stock issued upon conversion of such Security shall bear such
legend, unless the Company has reasonable cause to believe that such other
Security is a "restricted security" (or such shares of Common Stock are
"restricted securities") within the meaning of Rule 144 or Regulation S and
instructs the Trustee in writing to cause a Restricted Securities Legend to
appear thereon.

        Any Security (or Security issued in exchange or substitution therefor)
as to which such restrictions on transfer shall have expired in accordance with
their terms or as to which the

                                       21
<PAGE>

conditions for removal of the Restricted Securities Legend set forth in Section
2.3(a)(i) as set forth therein have been satisfied may, upon surrender of such
Security for exchange to the Registrar in accordance with the provisions of
Section 2.7, be exchanged for a new Security or Securities, of like tenor and
aggregate principal amount, which shall not bear the Restricted Securities
Legend required by Section 2.3(a)(i).

        Any stock certificate representing shares of Common Stock issued upon
conversion of any Security as to which such restrictions on transfer shall have
expired in accordance with their terms or as to which the conditions for removal
of the Restricted Securities Legend set forth in Section 2.3(a)(ii) as set forth
therein have been satisfied may, upon surrender of the stock certificates
representing such shares of Common Stock for exchange in accordance with the
procedures of the transfer agent for the Common Stock, be exchanged for a new
stock certificate or stock certificates representing a like aggregate number of
shares of Common Stock, which shall not bear the Restricted Securities Legend
required by Section 2.3(a)(ii).

  (b)  Global Security Legend.

        Each Global Security shall also bear the following legend on the face
thereof:

  THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE
  REFERRED TO HEREIN. THIS GLOBAL SECURITY MAY NOT BE EXCHANGED OR TRANSFERRED,
  IN WHOLE BUT NOT IN PART, FOR A SECURITY REGISTERED IN THE NAME OF ANY PERSON
  OTHER THAN DTC OR A NOMINEE THEREOF, EXCEPT IN THE LIMITED CIRCUMSTANCES SET
  FORTH IN THE INDENTURE. BENEFICIAL INTERESTS IN THIS GLOBAL SECURITY MAY NOT
  BE TRANSFERRED EXCEPT IN ACCORDANCE WITH THE INDENTURE.

  (c) Legend for Physical Securities.

        Physical Securities, in addition to the legend set forth in Section
  2.3(a)(i), will also bear a legend substantially in the following form:

  THIS SECURITY WILL NOT BE ACCEPTED IN EXCHANGE FOR A BENEFICIAL INTEREST IN A
  GLOBAL SECURITY UNLESS THE HOLDER OF THIS SECURITY, SUBSEQUENT TO SUCH
  EXCHANGE, WILL HOLD EITHER NO DEBENTURES OR A MINIMUM AGGREGATE BENEFICIAL
  INTEREST IN THE DEBENTURES OF AT LEAST (I) TWO HUNDRED FIFTY THOUSAND DOLLARS
  ($250,000), IF SUCH HOLDER IS A NON-INSTITUTIONAL INSTITUTIONAL ACCREDITED
  INVESTOR, OR (II) ONE HUNDRED THOUSAND DOLLARS ($100,000), IF SUCH HOLDER IS
  AN INSTITUTIONAL ACCREDITED INVESTOR.

  Section 2.4  Execution, Authentication, Delivery and Dating.

        Two Officers shall execute the Securities on behalf of the Company by
manual or facsimile signature. If an Officer whose signature is on a Security no
longer holds that office at the time the Security is authenticated, the Security
shall be valid nevertheless.

                                       22
<PAGE>

          At any time and from time to time after the execution and delivery of
this Indenture, the Company may deliver Securities executed by the Company to
the Trustee for authentication, together with a Company Order for the
authentication and delivery of such Securities, and the Trustee in accordance
with such Company Order shall authenticate and deliver such Securities as in
this Indenture provided and not otherwise.

          Each Security shall be dated the date of its authentication.

          No Security shall be entitled to any benefit under this Indenture, or
be valid or obligatory for any purpose, unless there appears on such Security a
certificate of authentication substantially in the form provided for herein
executed by or on behalf of the Trustee by manual signature, and such
certificate upon any Security shall be conclusive evidence, and the only
evidence, that such Security has been duly authenticated and delivered
hereunder.

          The Trustee may appoint an authenticating agent or agents reasonably
acceptable to the Company with respect to the Securities.  Unless limited by the
terms of such appointment, an authenticating agent may authenticate Securities
whenever the Trustee may do so.  Each reference in this Indenture to
authentication by the Trustee includes authentication by such agent.

  Section 2.5  Registrar and Paying Agent.

          The Company shall maintain an office or agency where Securities may be
presented for registration of transfer or for exchange (the "Registrar") and an
office or agency where Securities may be presented for payment (the "Paying
Agent").  The Registrar shall keep a register of the Securities (the "Register")
and of their transfer and exchange.  The Company may appoint one or more co-
Registrars and one or more additional Paying Agents for the Securities.  The
term "Paying Agent" includes any additional paying agent and the term
"Registrar" includes any additional registrar.  The Company may change any
Paying Agent or Registrar without prior notice to any Holder.

          The Company will cause each Paying Agent (other than the Trustee) to
execute and deliver to the Trustee an instrument in which such Paying Agent
shall agree with the Trustee, subject to the provisions of this Section, that
such Paying Agent will:

               (1) hold all sums held by it for the payment of the principal of
          and premium, if any, or interest (including Additional Amounts, if
          any) on Securities in trust for the benefit of the Persons entitled
          thereto until such sums shall be paid to such Persons or otherwise
          disposed of as provided in this Indenture;

               (2) give the Trustee notice of any Default by the Company in the
          making of any payment of principal and premium, if any, or interest
          (including Additional Amounts, if any); and

               (3) at any time during the continuance of any such Default, upon
          the written request of the Trustee, forthwith pay to the Trustee all
          sums so held in trust by such Paying Agent.

                                       23
<PAGE>

        The Company shall give prompt written notice to the Trustee of the
name and address of any Agent who is not a party to this Indenture.  If the
Company fails to appoint or maintain another entity as Registrar or Paying
Agent, the Trustee shall act as such.  The Company or any Affiliate of the
Company may act as Paying Agent or Registrar; provided, however, that none of
the Company, its subsidiaries or the Affiliates of the foregoing shall act:

        (i)  as Paying Agent in connection with redemptions, offers to purchase
     and discharges, except as otherwise specified in this Indenture, and

        (ii) as Paying Agent or Registrar if a Default or Event of Default has
     occurred and is continuing.

        The Company hereby initially appoints the Trustee as Registrar and
Paying Agent for the Securities.

  Section 2.6  Paying Agent to Hold Assets in Trust.

        Not later than 11:00 a.m. (New York City time) on each due date of the
principal, premium, if any, and interest (including Additional Amounts, if any)
on any Securities, the Company shall deposit with one or more Paying Agents
money in immediately available funds in an aggregate amount sufficient to pay
the principal, premium, if any, and interest (including Additional Amounts, if
any) due on such date.  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) shall have no further liability for the
money so paid over to the Trustee.

        If the Company shall act as a Paying Agent, it shall, prior to or on
each due date of the principal of and premium, if any, or interest (including
Additional Amounts, if any) on any of the Securities, segregate and hold in
trust for the benefit of the Holders a sum sufficient with monies held by all
other Paying Agents, to pay the principal and premium, if any, or interest
(including Additional Amounts, if any) so becoming due until such sums shall be
paid to such Persons or otherwise disposed of as provided in this Indenture, and
shall promptly notify the Trustee of its action or failure to act.

  Section 2.7  General Provisions Relating to Transfer and Exchange.

        The Securities are issuable only in registered form. A Holder may
transfer a Security only by written application to the Registrar stating the
name of the proposed transferee and otherwise complying with the terms of this
Indenture. No such transfer shall be effected until, and such transferee shall
succeed to the rights of a Holder only upon, final acceptance and registration
of the transfer by the Registrar in the Register. Furthermore, any Holder of a
Global Security shall, by acceptance of such Global Security, agree that
transfers of beneficial interests in such Global Security may be effected only
through a book-entry system maintained by the Holder of such Global Security (or
its agent) and that ownership of a beneficial interest in the Global Security
shall be required to be reflected in a book-entry. Notwithstanding the
foregoing, in the case of a Restricted Security, a beneficial interest in a
Global Security being transferred in reliance on an exemption from the
registration requirements of the Securities Act other than in

                                       24
<PAGE>

accordance with Rule 144, Regulation S or Rule 144A may only be transferred for
a Physical Security.

          When Securities are presented to the Registrar with a request to
register the transfer or to exchange them for an equal aggregate principal
amount of Securities of other authorized denominations, the Registrar shall
register the transfer or make the exchange as requested if its requirements for
such transactions are met (including that such Securities are duly endorsed or
accompanied by a written instrument of transfer duly executed by the Holder
thereof or by an attorney who is authorized in writing to act on behalf of the
Holder). Subject to Section 2.4, to permit registrations of transfers and
exchanges, the Company shall execute and the Trustee shall authenticate
Securities at the Registrar's request. No service charge shall be made for any
registration of transfer or exchange or redemption of the Securities, 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 taxes or other similar governmental charge payable upon exchanges
pursuant to Section 2.14, 7.5 or 10.7).

          Neither the Company nor the Registrar shall be required to exchange or
register a transfer of any Securities:

               (1) for a period of 15 Business Days prior to the day of any
          selection of Securities for redemption under Article 10;

               (2) so selected for redemption or, if a portion of any Security
          is selected for redemption, the portion thereof selected for
          redemption; or

               (3) surrendered for conversion or, if a portion of any Security
          is surrendered for conversion, the portion thereof surrendered for
          conversion.

     Section 2.8  Book-Entry Provisions for the Global Securities.

          (a)  The Global Securities initially shall:

               (i)   be registered in the name of the Depositary (or a nominee
          thereof);

               (ii)  be delivered to the Trustee as custodian for such
          Depositary; and

               (iii) bear the Restricted Securities Legend set forth in Section
          2.3(a)(i).

          Members of, or participants in, the Depositary ("Agent Members") shall
have no rights under this Indenture with respect to any Global Security held on
their behalf by the Depositary, or the Trustee as its custodian, or under such
Global Security, 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
Security for all purposes whatsoever.  Notwithstanding the foregoing, nothing
contained herein shall prevent the Company, the Trustee or any agent of the
Company or Trustee from giving effect to any written certification, proxy or
other authorization furnished by the Depositary or impair, as between the
Depositary and the Agent Members, the operation of customary practices governing
the exercise of the rights of a Holder of any Security. With respect to any
Global Security deposited on behalf of the subscribers for the Securities

                                       25
<PAGE>

represented thereby with the Trustee as custodian for the Depositary for credit
to their respective accounts (or to such other accounts as they may direct) at
Euroclear or Clearstream, the provisions of the "Operating Procedures of the
Euroclear System" and the "Terms and Conditions Governing Use of Euroclear" and
the "Management Regulations" and "Instructions to Participants" of Clearstream,
respectively, shall be applicable to the Global Securities.

          (b) The Holder of a Global Security may grant proxies and otherwise
authorize any Person, including DTC Participants and Persons that may hold
interests through DTC Participants, to take any action which a Holder is
entitled to take under this Indenture or the Securities.

          (c) A Global Security may not be transferred, in whole or in part, to
any Person other than the Depositary (or a nominee thereof), and no such
transfer to any such other Person may be registered.  Beneficial interests in a
Global Security may be transferred in accordance with the rules and procedures
of the Depositary and the provisions of Section 2.9.

          (d)  If at any time:

               (i)   the Depositary notifies the Company in writing that it is
     no longer willing or able to continue to act as Depositary for the Global
     Securities, or the Depositary ceases to be a "clearing agency" registered
     under the Exchange Act and a successor depositary for the Global Securities
     is not appointed by the Company within 90 days of such notice or cessation;

               (ii)  the Company, at its option, notifies the Trustee in writing
     that it elects to cause the issuance of the Physical Securities under this
     Indenture in exchange for all or any part of the Securities represented by
     a Global Security or Global Securities; or

               (iii) an Event of Default has occurred and is continuing and the
     Registrar has received a request from the Depositary for the issuance of
     Physical Securities in exchange for such Global Security or Global
     Securities;

the Depositary shall surrender such Global Security or Global Securities to the
Trustee for cancellation and the Company shall execute, and the Trustee, upon
receipt of an Officers' Certificate and Company Order for the authentication and
delivery of Securities, shall authenticate and deliver in exchange for such
Global Security or Global Securities, Physical Securities in an aggregate
principal amount equal to the aggregate principal amount of such Global Security
or Global Securities.  Such Physical Securities shall be registered in such
names as the Depositary shall identify in writing as the beneficial owners of
the Securities represented by such Global Security or Global Securities (or any
nominee thereof).

          (e) Notwithstanding the foregoing, in connection with any transfer of
beneficial interests in a Global Security to the beneficial owners thereof
pursuant to Section 2.8(d), the Registrar shall reflect on its books and records
the date and a decrease in the principal amount of such Global Security in an
amount equal to the principal amount of the beneficial interests in such Global
Security to be transferred.

                                       26
<PAGE>

  Section 2.9  Special Transfer Provisions.

          Unless a Security is (i) transferred after the time period referred to
in Rule 144(k) under the Securities Act or (ii) sold pursuant to a registration
statement that has been declared effective under the Securities Act (and which
continues to be effective at the time of such sale), the following provisions
shall apply to any sale, pledge or other transfer of Securities:

          (a)   Transfers of Securities to an Institutional Accredited Investor
                which is not a QIB or to a Non-institutional Accredited
                Investor.

          The following provisions shall apply with respect to the registration
of any proposed transfer of Securities to (x) an Institutional Accredited
Investor which is not a QIB, or (y) a Non-institutional Accredited Investor:

          (i)   The Registrar shall register the transfer if the proposed
     transferee has delivered to the Trustee (A) a certificate substantially in
     the form of Exhibit B annexed hereto and (B) such opinion of counsel and
                 ---------
     other evidence satisfactory to the Company that such transfer is in
     compliance with the Securities Act, as requested by the Company.

          (ii)  If the proposed transferor is an Agent Member holding a
     beneficial interest in Global Securities, upon receipt by the Registrar of
     the documents required by clause (i) of this Section 2.9(a) and
     instructions given in accordance with the procedures of Euroclear or
     Clearstream, if applicable, the Depositary and the Registrar, the Registrar
     shall reflect on its books and records, and Euroclear or Clearstream, if
     applicable, or the Registrar shall instruct the Depositary to note or cause
     to be noted on such Global Securities, the date and a decrease in the
     principal amount of the Global Securities in an amount equal to the
     principal amount of the beneficial interest in the Global Securities to be
     transferred, and the Company shall execute, and the Trustee shall
     authenticate and deliver, one or more Physical Securities of like tenor and
     amount registered in the name of the transferee.

          (iii) If the Securities to be transferred consist of Physical
     Securities, upon receipt by the Registrar of the documents required by
     clause (i) of this Section 2.9(a), the Company shall execute and the
     Trustee shall authenticate and deliver, new Physical Securities registered
     in the name of the transferee and the Trustee shall cancel the Physical
     Securities presented for transfer.

          (b)   Transfer of Securities to a QIB or to a Non-U.S. Person in
                Accordance with Regulation S.

          The following provisions shall apply with respect to the registration
of any proposed transfer of Securities to (x) a QIB or (y) a Non-U.S. Person in
Accordance with Regulation S:

          (i)   If the Securities to be transferred consist of a beneficial
     interest in the Global Securities, the transfer of such interest may be
     effected only through the book-entry systems maintained by Euroclear and
     Clearstream, if applicable, and the Depositary.

                                       27
<PAGE>

          (ii)  If the Securities to be transferred consist of Physical
     Securities, the Registrar shall register the transfer if such transfer is
     being made by a proposed transferor who has checked the box provided for on
     the form of Security stating (or has otherwise advised the Company and the
     Registrar in writing) that the sale has been made:

               (A) in compliance with the provisions of Rule 144A to a
          transferee who has signed the certification provided for on the form
          of Security stating or has otherwise advised the Company and the
          Registrar in writing that:

                   (1) it is purchasing the Securities for its own account or an
               account with respect to which it exercises sole investment
               discretion, in each case for investment and not with a view to
               distribution;

                   (2) it and any such account is a QIB within the meaning of
               Rule 144A;

                   (3) it is aware that the sale to it is being made in reliance
               on Rule 144A;

                   (4) it acknowledges that it has received such information
               regarding the Company as it has requested pursuant to Rule 144A
               or has determined not to request such information; and

                   (5) it is aware that the transferor is relying upon its
               foregoing representations in order to claim the exemption from
               registration provided by Rule 144A, or

               (B) in compliance with Regulation S to a transferee who has
          signed a certification provided for on the form of Security stating
          (or has otherwise advised the Company and the Registrar in writing)
          that it is not a "U.S. person" as defined in Regulation S.

          In addition, the Registrar shall reflect on its books and records the
date and an increase in the principal amount of the Global Securities in an
amount equal to the aggregate principal amount of the Physical Securities to be
transferred, and the Trustee shall cancel the Physical Securities so
transferred.

          (c)  Other Exchanges.

          In the event that Global Securities are exchanged for Securities in
definitive registered form pursuant to Section 2.8 prior to the effectiveness of
a Shelf Registration Statement with respect to such Securities, such Securities
may be exchanged only in accordance with the provisions of clauses (a) and (b)
above (including the certification requirements intended to ensure that such
transfers comply with Rule 144A or Regulation S, as the case may be) and such
other procedures as may from time to time be adopted by the Company.

                                       28
<PAGE>

          (d)   General.

          By its acceptance of any Security bearing the Restricted Securities
Legend, each Holder of such a Security acknowledges the restrictions on transfer
of such Security set forth in this Indenture and agrees that it will transfer
such Security only as provided in this Indenture.  The Registrar shall not
register a transfer of any Security unless such transfer complies with the
restrictions on transfer of such Security set forth in this Indenture.  The
Registrar shall be entitled to receive and rely on written instructions from the
Company verifying that such transfer complies with such restrictions on
transfer.  In connection with any transfer of Securities, each Holder agrees by
its acceptance of the Securities to furnish the Registrar or the Company such
certifications, legal opinions or other information as either of them may
reasonably require to confirm that such transfer is being made pursuant to an
exemption from, or a transaction not subject to, the registration requirements
of the Securities Act; provided that the Registrar shall not be required to
determine (but may rely on a determination made by the Company with respect to)
the sufficiency of any such certifications, legal opinions or other information.

          The Registrar shall retain copies of all certifications, letters,
notices and other written communications received pursuant to Section 2.8 hereof
or this Section 2.9.  The Company shall have the right to inspect and make
copies of all such letters, notices or other written communications at any
reasonable time upon the giving of reasonable written notice to the Registrar.

  Section 2.10 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 and shall otherwise comply with Section 312(a) of the TIA.  If the
Trustee is not the Registrar, the Company shall furnish to the Trustee prior to
or on 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 relating to such
Interest Payment Date or request, as the case may be.

  Section 2.11 Persons Deemed Owners.

          The Company, the Trustee and any agent of the Company or the Trustee
may treat the Holder as the owner of such Security for the purpose of receiving
payment of principal of and premium, if any, and interest (including Additional
Amounts, if any) on such Security and for all other purposes whatsoever, whether
or not such Security be overdue, and notwithstanding any notice of ownership or
writing thereon, or any notice of previous loss or theft or other interest
therein.

  Section 2.12 Mutilated, Destroyed, Lost or Stolen Securities.

          If any mutilated Security is surrendered to the Trustee, the Company
shall execute and the Trustee shall authenticate and deliver in exchange
therefor a new Security of like tenor and principal amount and bearing a number
not contemporaneously outstanding.

          If there is delivered to the Company and the Trustee

                                       29
<PAGE>

               (1) evidence to their satisfaction of the destruction, loss or
          theft of any Security, and

               (2) such security or indemnity as may be required by them to save
          each of them and any agent of either of them harmless, then, in the
          absence of notice to the Company or the Trustee that such Security has
          been acquired by a bona fide purchaser, the Company shall execute and,
          upon request, the Trustee shall authenticate and deliver, in lieu of
          any such destroyed, lost or stolen Security, a new Security of like
          tenor and principal amount and bearing a number not contemporaneously
          outstanding.

          In case any such mutilated, destroyed, lost or stolen Security has
become or is about to become due and payable, the Company in its discretion, but
subject to any conversion rights, may, instead of issuing a new Security, pay
such Security, upon satisfaction of the condition set forth in the preceding
paragraph.

          Upon the issuance of any new Security under this Section, the Company
may require the payment of a sum sufficient to cover any tax or other
governmental charge that may be imposed in relation thereto and any other
expenses (including the fees and expenses of the Trustee) connected therewith.

          Every new Security issued pursuant to this Section 2.12 in lieu of any
destroyed, lost or stolen Security shall constitute an original additional
contractual obligation of the Company, whether or not the destroyed, lost or
stolen Security shall be at any time enforceable by anyone, and such new
Security shall be entitled to all the benefits of this Indenture equally and
proportionately with any and all other Securities duly issued hereunder.

          The provisions of this Section 2.12 are exclusive and shall preclude
(to the extent lawful) all other rights and remedies with respect to the
replacement or payment of mutilated, destroyed, lost or stolen Securities.

  Section 2.13 Treasury Securities.

          In determining whether the Holders of the requisite principal amount
of Outstanding Securities are present at a meeting of Holders for quorum
purposes or have given any request, demand, authorization, direction, notice,
consent or waiver hereunder, Securities owned by the Company or any Affiliate of
the Company shall be disregarded and deemed not to be Outstanding, except that,
in determining whether the Trustee shall be protected in relying upon any such
determination as to the presence of a quorum or upon any such request, demand,
authorization, direction, notice, consent or waiver, only such Securities of
which the Trustee has received written notice and are so owned shall be so
disregarded.

  Section 2.14 Temporary Securities.

          Pending the preparation of Securities in definitive form, the Company
may execute and the Trustee shall, upon written request of the Company,
authenticate and deliver temporary Securities (printed or lithographed).
Temporary Securities shall be issuable in any authorized denomination, and
substantially in the form of the Securities in definitive form but

                                       30
<PAGE>

with such omissions, insertions and variations as may be appropriate for
temporary Securities, all as may be determined by the Company. Every such
temporary Security shall be executed by the Company and authenticated by the
Trustee upon the same conditions and in substantially the same manner, and with
the same effect, as the Securities in definitive form. Without unreasonable
delay, the Company will execute and deliver to the Trustee Securities in
definitive form (other than in the case of Securities in global form) and
thereupon any or all temporary Securities (other than any such Securities in
global form) may be surrendered in exchange therefor, at each office or agency
maintained by the Company pursuant to Section 9.2 and the Trustee shall
authenticate and deliver in exchange for such temporary Securities an equal
aggregate principal amount of Securities in definitive form. Such exchange shall
be made by the Company at its own expense and without any charge therefor. Until
so exchanged, the temporary Securities shall in all respects be entitled to the
same benefits and subject to the same limitations under this Indenture as
Securities in definitive form authenticated and delivered hereunder.

  Section 2.15 Cancellation.

          All securities surrendered for payment, redemption, repurchase,
conversion, registration of transfer or exchange shall, if surrendered to any
Person other than the Trustee, be delivered to the Trustee.  All Securities so
delivered shall be canceled promptly by the Trustee, and no Securities shall be
issued in lieu thereof except as expressly permitted by any of the provisions of
this Indenture.  Upon written instructions of the Company, the Trustee shall
destroy canceled Securities and, after such destruction, shall deliver a
certificate of such destruction to the Company.  If the Company shall acquire
any of the Securities, such acquisition shall not operate as a redemption or
satisfaction of the indebtedness represented by such Securities unless the same
are delivered to the Trustee for cancellation.

  Section 2.16 CUSIP Numbers.

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

  Section 2.17 Defaulted Interest.

          If the Company fails to make a payment of interest (including
Additional Amounts, if any) on any Security when due and payable ("Defaulted
Interest"), it shall pay such Defaulted Interest plus (to the extent lawful) any
interest payable on the Defaulted Interest, in any lawful manner.  It may elect
to pay such Defaulted Interest, plus any such interest payable on it, to the
Persons who are Holders of such Securities on which the interest is due on a
subsequent Special Record Date.  The Company shall notify the Trustee in writing
of the amount of Defaulted Interest proposed to be paid on each such Security.
The Company shall fix any such

                                       31
<PAGE>

Special Record Date and payment date for such payment. At least 15 days before
any such Special Record Date, the Company shall mail to Holders affected thereby
a notice that states the Special Record Date, the Interest Payment Date, and
amount of such interest (and such Additional Amounts, if any) to be paid.

                                   ARTICLE 3

                          SATISFACTION AND DISCHARGE

  Section 3.1  Satisfaction and Discharge of Indenture.

          When:

               (1) the Company shall deliver to the Trustee for cancellation all
     Securities previously authenticated (other than any Securities which have
     been destroyed, lost or stolen and in lieu of, or in substitution for
     which, other Securities shall have been authenticated and delivered) and
     not previously canceled; or

               (2) all the Securities not previously canceled or delivered to
     the Trustee for cancellation shall have become due and payable, or are by
     their terms to become due and payable within one year or are to be called
     for redemption within one year under arrangements satisfactory to the
     Trustee for the giving of notice of redemption;

               (3) the Company shall deposit with the Trustee, in trust, cash in
     U.S. dollars and/or U.S. Government Obligations which through the payment
     of interest and principal in respect thereof, in accordance with their
     terms, will provide (and without reinvestment and assuming no tax liability
     will be imposed on such Trustee), not later than one day before the due
     date of any payment of money, an amount in cash, sufficient, in the opinion
     of a nationally recognized firm of independent public accountants expressed
     in a written certification thereof delivered to the Trustee, to pay
     principal of, premium, if any, or interest (including Additional Amounts,
     if any) on all of the Securities (other than any Securities which shall
     have been mutilated, destroyed, lost or stolen and in lieu of or in
     substitution for which other Securities shall have been authenticated and
     delivered) not previously canceled or delivered to the Trustee for
     cancellation, on the dates such payments of principal, premium, if any, or
     interest (including Additional Amounts, if any) are due to such date of
     maturity or redemption, as the case may be; and

               (4) the Company shall have delivered to the Trustee an Officers'
     Certificate and an Opinion of Counsel to the effect that (x) the Company
     has received from, or there has been published by, the Internal Revenue
     Service a ruling or (y) since the date of execution of this Indenture,
     there has been a change in the applicable federal income tax law, in the
     case of either clause (x) or (y) to the effect that, and based thereon such
     Opinion of Counsel shall confirm that, the Holders will not recognize
     income, gain or loss for federal income tax purposes as a result of such
     deposit and discharge and will

                                       32
<PAGE>

          be subject to federal income tax on the same amount and in the same
          manner and at the same times as would have been the case if such
          deposit and discharge had not occurred; and

if, in the case of either clause (3) or (4), the Company shall also pay or cause
to be paid all other sums payable hereunder by the Company, then this Indenture
shall cease to be of further effect (except as to:

               (i)   remaining rights of registration of transfer, substitution
            and exchange and conversion of Securities;

               (ii)  rights hereunder of Holders to receive payments of
            principal of and premium, if any, and interest (including Additional
            Amounts, if any) on, the Securities and the other rights, duties and
            obligations of Holders, as beneficiaries hereof with respect to the
            amounts, if any, so deposited with the Trustee; and

               (iii) the rights, obligations and immunities of the Trustee
            hereunder);

and the Trustee, on demand of the Company accompanied by an Officers'
Certificate and an Opinion of Counsel and at the cost and expense of the
Company, shall execute proper instruments acknowledging satisfaction of and
discharging this Indenture; provided, however, that the Company shall reimburse
the Trustee for all amounts due the Trustee under Section 5.8 and for any costs
or expenses thereafter reasonably and properly incurred by the Trustee and to
compensate the Trustee for any services thereafter reasonably and properly
rendered by the Trustee in connection with this Indenture or the Securities.

  Section 3.2  Deposited Monies to be Held in Trust.

          Subject to Section 3.3, all monies deposited with the Trustee pursuant
to Section 3.1 shall be held in trust and applied by it to the payment,
notwithstanding the provisions of Article 13, either directly or through any
Paying Agent (including the Company if acting as its own Paying Agent), to the
Holders of the particular Securities for the payment or redemption of which such
monies have been deposited with the Trustee, of all sums due and to become due
thereon for principal, premium, if any, and interest (including Additional
Amounts, if any).  All monies deposited with the Trustee pursuant to Section 3.1
(and held by it or any Paying Agent) for the payment of Securities subsequently
converted shall be returned to the Company upon request of the Company.

  Section 3.3  Return of Unclaimed Monies.

          The Trustee and the Paying Agent shall pay to the Company any money
held by them for the payment of principal or premium, if any, or interest
(including Additional Amounts, if any) that remains unclaimed for two years
after the date upon which such payment shall have become due.  After payment to
the Company, Holders entitled to the money must look to the Company for payment
as general creditors unless an applicable abandoned property law designates
another Person, and all liability of the Trustee and such Paying Agent with
respect to such money shall cease.

                                       33
<PAGE>

                                   ARTICLE 4

                             DEFAULTS AND REMEDIES

  Section 4.1  Events of Default.

          An "Event of Default" with respect to the Securities occurs when any
of the following occurs (whatever the reason for such Event of Default and
whether it shall be occasioned by the provisions of Article 13 or be voluntary
or involuntary or be effected by operation of law or pursuant to any judgment,
decree or order of any court or any order, rule or regulation of any
administrative or governmental body):

          (a) the Company defaults in the payment of the principal of or
     premium, if any, on any of the Securities when it becomes due and payable
     at Maturity, upon redemption or exercise of a Repurchase Right or
     otherwise, whether or not such payment is prohibited by Article 13; or

          (b) the Company defaults in the payment of interest (including
     Additional Amounts or Interest Make-Whole Payment, if any) on any of the
     Securities when it becomes due and payable and such default continues for a
     period of 30 days, whether or not such payment is prohibited by Article 13;
     or

          (c) the Company fails to perform or observe any other term, covenant
     or agreement contained in the Securities or this Indenture and the default
     continues for a period of 60 days after written notice of such failure,
     requiring the Company to remedy the same, shall have been given to the
     Company by the Trustee or to the Company and the Trustee by the Holders of
     at least 25% in aggregate principal amount of the Outstanding Securities;
     or

          (d) (i) the Company fails to make by the end of the applicable grace
     period, if any, any payment of principal or interest due in respect of any
     Indebtedness for borrowed money, the aggregate outstanding principal amount
     of which is an amount in excess of $7,500,000; or (ii) there is an
     acceleration of any Indebtedness for borrowed money in an amount in excess
     of $7,500,000 because of a default with respect to such Indebtedness
     without such Indebtedness having been discharged or such non-payment or
     acceleration having been cured, waived, rescinded or annulled, in the case
     of either (i) or (ii) above, for a period of 30 days after written notice
     to the Company by the Trustee or to the Company and the Trustee by Holders
     of at least 25% in aggregate principal amount of the Outstanding
     Securities; or

          (e) the entry by a court having jurisdiction in the premises of (i) a
     decree or order for relief in respect of the Company in an involuntary case
     or proceeding under any applicable U.S. federal or state bankruptcy,
     insolvency, reorganization or other similar law or (ii) a decree or order
     adjudging the Company a bankrupt or insolvent, or approving as properly
     filed a petition seeking reorganization, arrangement, adjustment or
     composition of or in respect of the Company under any applicable U.S.
     federal or state law, or appointing a custodian, receiver, liquidator,
     assignee, trustee, sequestrator or other

                                       34
<PAGE>

  similar official of the Company or of any substantial part of its property, or
  ordering the winding up or liquidation of its affairs, and the continuance of
  any such decree or order for relief or any such other decree or order unstayed
  and in effect for a period of 60 consecutive days; or

          (f) the commencement by the Company of a voluntary case or proceeding
  under any applicable U.S. federal or state bankruptcy, insolvency,
  reorganization or other similar law or of any other case or proceeding to be
  adjudicated a bankrupt or insolvent, or the consent by the Company to the
  entry of a decree or order for relief in respect of the Company in an
  involuntary case or proceeding under any applicable U.S. federal or state
  bankruptcy, insolvency, reorganization or other similar law or to the
  commencement of any bankruptcy or insolvency case or proceeding against the
  Company, or the filing by the Company of a petition or answer or consent
  seeking reorganization or relief under any applicable U.S. federal or state
  law, or the consent by the Company to the filing of such petition or to the
  appointment of or the taking possession by a custodian, receiver, liquidator,
  assignee, trustee, sequestrator or other similar official of the Company or of
  any substantial part of its property, or the making by the Company of an
  assignment for the benefit of creditors, or the admission by the Company in
  writing of its inability to pay its debts generally as they become due, or the
  taking of corporate action by the Company expressly in furtherance of any such
  action.

  Section 4.2  Acceleration of Maturity; Rescission and Annulment.

          If an Event of Default with respect to Outstanding Securities (other
than an Event of Default specified in Section 4.1(e) or 4.1(f)) occurs and is
continuing, the Trustee or the Holders of at least 25% in aggregate principal
amount of the Outstanding Securities, by written notice to the Company, may
declare due and payable 100% of the principal amount of all Outstanding
Securities plus any accrued and unpaid interest (including Additional Amounts,
if any) to the date of payment.  Upon a declaration of acceleration, such
principal and accrued and unpaid interest (including Additional Amounts, if any)
to the date of payment shall be immediately due and payable.

          If an Event of Default specified in Section 4.1(e) or 4.1(f) occurs,
all unpaid principal and accrued and unpaid interest (including Additional
Amounts, if any) on the Outstanding Securities shall become and be immediately
due and payable, without any declaration or other act on the part of the Trustee
or any Holder.

          The Holders either (a) through notice to the Trustee of not less than
a majority in aggregate principal amount of the Outstanding Securities, or (b)
by the adoption of a resolution, at a meeting of Holders of the Outstanding
Securities at which a quorum is present, by the Holders of at least a majority
in aggregate principal amount of the Outstanding Securities represented at such
meeting, may, on behalf of the Holders of all of the Securities, rescind and
annul an acceleration and its consequences if:

               (1) all existing Events of Default, other than the nonpayment of
          principal of or interest on the Securities which have become due
          solely because of the acceleration, have been remedied, cured or
          waived, and

                                       35
<PAGE>

               (2) the rescission would not conflict with any judgment or decree
          of a court of competent jurisdiction;

provided, however, that in the event such declaration of acceleration has been
made based on the existence of an Event of Default under Section 4.1(d) and the
default with respect to Indebtedness for money borrowed which gave rise to such
Event of Default has been remedied, cured or waived, then, without any further
action by the Holders, such declaration of acceleration shall be rescinded
automatically and the consequences of such declaration shall be annulled.  No
such rescission or annulment shall affect any subsequent Default or impair any
right consequent thereon.

  Section 4.3  Other Remedies.

          If an Event of Default with respect to Outstanding Securities occurs
and is continuing, the Trustee may pursue any available remedy by proceeding at
law or in equity to collect the payment of principal of or interest on the
Securities or to enforce the performance of any provision of the Securities.

          The Trustee may maintain a proceeding in which it may prosecute and
enforce all rights of action and claims under this Indenture or the Securities,
even if it does not possess any of the Securities or does not produce any of
them in the proceeding.

  Section 4.4  Waiver of Past Defaults.

          The Holders, either (a) through the written consent of not less than a
majority in aggregate principal amount of the Outstanding Securities, or (b) by
the adoption of a resolution, at a meeting of Holders of the Outstanding
Securities at which a quorum is present, by the Holders of at least a majority
in aggregate principal amount of the Outstanding Securities represented at such
meeting, may, on behalf of the Holders of all of the Securities, waive an
existing Default or Event of Default, except a Default or Event of Default:

               (1) in the payment of the principal of or premium, if any, or
          interest (including Additional Amounts, if any) on any Security
          (provided, however, that subject to Section 4.7, the Holders of a
          majority in aggregate principal amount of the Outstanding Securities
          may rescind an acceleration and its consequences, including any
          related payment default that resulted from such acceleration); or

               (2) in respect of a covenant or provision hereof which, under
          Section 7.2, cannot be modified or amended without the consent of the
          Holders of each Outstanding Security affected.

Upon any such waiver, such Default shall cease to exist, and any Event of
Default arising therefrom shall be deemed to have been cured, for every purpose
of this Indenture; provided, however, that no such waiver shall extend to any
subsequent or other Default or impair any right consequent thereon.

                                       36
<PAGE>

  Section 4.5  Control by Majority.

          The Holders of a majority in aggregate principal amount of the
Outstanding Securities (or such lesser amount as shall have acted at a meeting
pursuant to the provisions of this Indenture) shall have the right to direct the
time, method and place of conducting any proceeding for any remedy available to
the Trustee or exercising any trust or power conferred on the Trustee.  However,
the Trustee may refuse to follow any direction that:

               (1) conflicts with any law or with this Indenture;

               (2) the Trustee determines may be unduly prejudicial to the
          rights of the Holders not joining therein; or

               (3) may expose the Trustee to personal liability.

The Trustee may take any other action deemed proper by the Trustee which is not
inconsistent with such direction.

  Section 4.6  Limitation on Suit.

          No Holder of any Security shall have any right to pursue any remedy
with respect to this Indenture or the Securities (including, instituting any
proceeding, judicial or otherwise, with respect to this Indenture or for the
appointment of a receiver or trustee) unless:

               (1) such Holder has previously given written notice to the
          Trustee of an Event of Default that is continuing;

               (2) the Holders of at least 25% in aggregate principal amount of
          the Outstanding Securities shall have made written request to the
          Trustee to pursue the remedy;

               (3) such Holder or Holders have offered to the Trustee indemnity
          satisfactory to it against any costs, expenses and liabilities
          incurred in complying with such request;

               (4) the Trustee has failed to comply with the request for 60 days
          after its receipt of such notice, request and offer of indemnity; and

               (5) during such 60-day period, no direction inconsistent with
          such written request has been given to the Trustee by the Holders of a
          majority in aggregate principal amount of the Outstanding Securities
          (or such amount as shall have acted at a meeting pursuant to the
          provisions of this Indenture);

provided, however, that no one or more of such Holders may use this Indenture to
prejudice the rights of another Holder or to obtain preference or priority over
another Holder.

                                       37
<PAGE>

  Section 4.7  Unconditional Rights of Holders to Receive Payment and to
               Convert.

          Notwithstanding any other provision in this Indenture, the Holder of
any Security shall have the right, which is absolute and unconditional, to
receive payment of the principal of and premium, if any, and interest (including
Additional Amounts, if any) on such Security on the Stated Maturity expressed in
such Security (or, in the case of redemption, on the Redemption Date, or in the
case of the exercise of a Repurchase Right, on the Repurchase Date) and to
convert such Security in accordance with Article 12, and to bring an action for
the enforcement of any such payment on or after such respective dates and such
right to convert, and such rights shall not be impaired or affected without the
consent of such Holder.

  Section 4.8  Collection of Indebtedness and Suits for Enforcement by the
               Trustee.

          The Company covenants that if:

               (1) a Default or Event of Default is made in the payment of any
          interest (including Additional Amounts, if any) on any Security when
          such interest (including Additional Amounts, if any) becomes due and
          payable and such Default or Event of Default continues for a period of
          30 days; or

               (2) a Default or Event of Default is made in the payment of the
          principal of or premium, if any, on any Security at the Maturity
          thereof;

the Company will, upon demand of the Trustee, pay to it, for the benefit of the
Holders of such Securities, the whole amount then due and payable (as expressed
therein or as a result of any acceleration effected pursuant to Section 4.2) on
such Securities for principal and premium, if any, and interest (including
Additional Amounts, if any) and, to the extent that payment of such interest
shall be legally enforceable, interest on any overdue principal and premium, if
any, and on any overdue interest (including Additional Amounts, if any),
calculated using the Interest Rate, and, in addition thereto, such further
amount as shall be sufficient to cover the costs and expenses of collection,
including the reasonable compensation, expenses, disbursements and advances of
the Trustee, its agents and counsel.

          If the Company fails to pay such amounts forthwith upon such demand,
the Trustee, in its own name and as trustee of an express trust, may institute a
judicial proceeding for the collection of the sums so due and unpaid, may
prosecute such proceeding to judgment or final decree and may enforce the same
against the Company and collect the monies adjudged or decreed to be payable in
the manner provided by law out of the property of the Company, wherever
situated.

          If an Event of Default occurs and is continuing, the Trustee may in
its discretion proceed to protect and enforce its rights and the rights of the
Holders of Securities by such appropriate judicial proceedings as the Trustee
shall deem most effectual to protect and enforce any such rights, whether for
the specific enforcement of any covenant or agreement in this Indenture or in
aid of the exercise of any power granted herein, or to enforce any other proper
remedy.

                                       38
<PAGE>

  Section 4.9  Trustee May File Proofs of Claim.

          In case of the pendency of any receivership, insolvency, liquidation,
bankruptcy, reorganization, arrangement, adjustment, composition or other
judicial proceeding relative to the Company or the property of the Company or
its creditors, the Trustee (irrespective of whether the principal of the
Securities shall then be due and payable as therein expressed or by declaration
or otherwise and irrespective of whether the Trustee shall have made any demand
on the Company for the payment of overdue principal or interest (including
Additional Amounts, if any)) shall be entitled and empowered, by intervention in
such proceeding or otherwise:

               (1) to file and prove a claim for the whole amount of principal
          and premium, if any, and interest (including Additional Amounts, if
          any) owing and unpaid in respect of the Securities and to file such
          other papers or documents as may be necessary or advisable in order to
          have the claims of the Trustee (including any claim for the reasonable
          compensation, expenses, disbursements and advances of the Trustee, its
          agents and counsel) and of the Holders of Securities allowed in such
          judicial proceeding; and

               (2) to collect and receive any monies or other property payable
          or deliverable on any such claim and to distribute the same;

and any custodian, receiver, assignee, trustee, liquidator, sequestrator or
other similar official in any such judicial proceedings is hereby authorized by
each Holder of Securities to make such payments to the Trustee and, in the event
that the Trustee shall consent to the making of such payments directly to the
Holders of Securities, to pay to the Trustee any amount due to it for the
reasonable compensation, expenses, disbursements and advances of the Trustee,
its agents and counsel and any other amounts due the Trustee under Section 5.8.

          Nothing contained herein shall be deemed to authorize the Trustee to
authorize or consent to or accept, or adopt on behalf of any Holder of a
Security, any plan of reorganization, arrangement, adjustment or composition
affecting the Securities or the rights of any Holder thereof or to authorize the
Trustee to vote in respect of the claim of any Holder of a Security in any such
proceeding.

  Section 4.10 Restoration of Rights and Remedies.

          If the Trustee or any Holder of a Security has instituted any
proceeding to enforce any right or remedy under this Indenture and such
proceeding has been discontinued or abandoned for any reason, or has been
determined adversely to the Trustee or to such Holder, then and in every such
case, subject to any determination in such proceeding, the Company, the Trustee
and the Holders of Securities shall be restored severally and respectively to
their former positions hereunder and thereafter all rights and remedies of the
Trustee and the Holders shall continue as though no such proceeding had been
instituted.

  Section 4.11 Rights and Remedies Cumulative.

          Except as otherwise provided with respect to the replacement or
payment of mutilated, destroyed, lost or stolen Securities in the last paragraph
of Section 2.12, no right or

                                       39
<PAGE>

remedy conferred in this Indenture upon or reserved to the Trustee or to the
Holders of Securities is intended to be exclusive of any other right or remedy,
and every right and remedy shall, to the extent permitted by law, be cumulative
and in addition to every other right and remedy given hereunder or hereafter
existing at law or in equity or otherwise. The assertion or employment of any
right or remedy hereunder, or otherwise, shall not prevent the concurrent
assertion or employment of any other appropriate right or remedy.

  Section 4.12 Delay or Omission Not Waiver.

          No delay or omission of the Trustee or of any Holder of any Security
to exercise any right or remedy accruing upon any Event of Default shall impair
any such right or remedy or constitute a waiver of any such Event of Default or
any acquiescence therein.  Every right and remedy given by this Article or by
law to the Trustee or to the Holders of Securities may be exercised from time to
time, and as often as may be deemed expedient, by the Trustee or by the Holders
of Securities, as the case may be.

  Section 4.13 Application of Money Collected.

          Subject to Article 13, any money collected by the Trustee pursuant to
this Article shall be applied in the following order, at the date or dates fixed
by the Trustee and, in case of the distribution of such money on account of
principal or premium, if any, or interest (including Additional Amounts, if
any), upon presentation of the Securities and the notation thereon of the
payment if only partially paid and upon surrender thereof if fully paid:

          FIRST:  To the payment of all amounts due the Trustee;

          SECOND:  To the payment of the amounts then due and unpaid for
          principal of and premium, if any, and interest (including Additional
          Amounts, if any) on the Securities and coupons in respect of which or
          for the benefit of which such money has been collected, ratably,
          without preference or priority of any kind, according to the amounts
          due and payable on such Securities for principal and premium, if any,
          and interest (including Additional Amounts, if any), respectively; and

          THIRD:  Any remaining amounts shall be repaid to the Company.

  Section 4.14 Undertaking for Costs.

          All parties to this Indenture agree, and each Holder of any Security
by such Holder's acceptance thereof shall be deemed to have agreed, that any
court may in its discretion require, in any suit for the enforcement of any
right or remedy under this Indenture, or in any suit against the Trustee for any
action taken, suffered or omitted by it as Trustee, the filing by any party
litigant in such suit of an undertaking to pay the costs of such suit, and that
such court may in its discretion assess reasonable costs, including reasonable
attorneys' fees, against any party litigant in such suit, having due regard to
the merits and good faith of the claims or defenses made by such party litigant;
but the provisions of this Section shall not apply to any suit instituted by the
Company, to any suit instituted by the Trustee, to any suit instituted by any
Holder, or group of Holders, holding in the aggregate more than 10% in aggregate
principal amount of the Outstanding Securities, or to any suit instituted by any
Holder of any Security for

                                       40
<PAGE>

the enforcement of the payment of the principal of or premium, if any, or
interest (including Additional Amounts, if any) on any Security on or after the
Stated Maturity expressed in such Security (or, in the case of redemption or
exercise of a Repurchase Right, on or after the Redemption Date) or for the
enforcement of the right to convert any Security in accordance with Article 12.

  Section 4.15 Waiver of Stay or Extension Laws.

          The Company covenants (to the extent that it may lawfully do so) that
it will not at any time insist upon, or plead, or in any manner whatsoever claim
to take the benefit or advantage of, any stay or extension 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 that it may
lawfully do so) hereby expressly waives all benefit or advantage of any such law
and covenants that it will not 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.

                                   ARTICLE 5

                                  THE TRUSTEE

  Section 5.1  Certain Duties and Responsibilities.

          (a)  Except during the continuance of an Event of Default,

               (1) The Trustee undertakes to perform such duties and only such
          duties as are specifically set forth in this Indenture or the TIA, and
          no implied covenants or obligations shall be read into this Indenture
          against the Trustee; and

               (2) In the absence of bad faith on its part, the Trustee may
          conclusively rely, as to the truth of the statements and the
          correctness of the opinions expressed therein, upon certificates or
          opinions furnished to the Trustee and conforming to the requirements
          of this Indenture; provided, however, that in the case of any such
          certificates or opinions which by any provision hereof are
          specifically required to be furnished to the Trustee, the Trustee
          shall examine the certificates or opinions to determine whether or
          not, on their face, they conform to the requirements to this Indenture
          (but need not investigate or confirm the accuracy of any facts stated
          therein).

          (b) In case an Event of Default actually known to a Responsible
Officer of the Trustee has occurred and is continuing, the Trustee shall
exercise such of the rights and powers vested in it by this Indenture, and use
the same degree of care and skill in their exercise, as a prudent person would
exercise or use under the circumstances in the conduct of such person's own
affairs.

          (c) No provision of this Indenture shall be construed to relieve the
Trustee from liability for its own negligent action, its own negligent failure
to act, or its own willful misconduct, except that:

                                       41
<PAGE>

               (1) This paragraph (c) shall not be construed to limit the effect
          of paragraph (a) of this Section 5.1;

               (2) The Trustee shall not be liable for any error of judgment
          made in good faith by a Responsible Officer, unless it shall be proved
          that the Trustee was negligent in ascertaining the pertinent facts;
          and

               (3) The Trustee shall not be liable with respect to any action
          taken or omitted to be taken by it in good faith in accordance with a
          direction received by it of the Holders of a majority in principal
          amount of the Outstanding Securities (or such lesser amount as shall
          have acted at a meeting pursuant to the provisions of this Indenture)
          relating to the time, method and place of conducting any proceeding
          for any remedy available to the Trustee, or exercising any trust or
          power conferred upon the Trustee, under this Indenture.

          (d) Whether or not herein expressly so provided, every provision of
this Indenture relating to the conduct or affecting the liability of or
affording protection to the Trustee shall be subject to the provisions of this
Section 5.1.

          (e) No provision of this Indenture shall require the Trustee to expend
or risk its own funds or otherwise incur any liability in the performance of any
of its duties hereunder, or in the exercise of any of its rights or powers.  The
Trustee may refuse to perform any duty or exercise any right or power unless it
receives indemnity satisfactory to it against any loss, liability, cost or
expense (including, without limitation, reasonable fees of counsel).

          (f) The Trustee shall not be obligated to pay interest on any money or
other assets received by it unless otherwise agreed in writing with the Company.
Assets held in trust by the Trustee need not be segregated from other funds
except to the extent required by law.

          (g) The Trustee shall not be bound to make any investigation into the
facts or matters stated in any resolution, certificate, statement, instrument,
opinion, report, notice, request, direction, consent, order, bond, debenture,
note, coupon, other evidence of indebtedness or other paper or document, but the
Trustee, in its discretion, may make such further inquiry or investigation into
such facts or matters as it may see fit, and, if the Trustee shall determine to
make such further inquiry or investigation, it shall be entitled to examine the
books, records and premises of the Company, personally or by agent or attorney
at the sole cost of the Company and shall incur no liability or additional
liability of any kind by reason of such inquiry or investigation.

          (h) The Trustee shall not be deemed to have notice or actual knowledge
of any Event of Default unless a Responsible Officer of the Trustee has actual
knowledge thereof or unless written notice of any event which is in fact a
Default is received by the Trustee pursuant to Section 14.2, and such notice
references the Securities and this Indenture.

          (i) The rights, privileges, protections, immunities and benefits given
to the Trustee hereunder, including, without limitation, its right to be
indemnified, are extended to, and shall be enforceable by, the Trustee in each
of its capacities hereunder, and each Paying Agent, authenticating agent,
Conversion Agent or Registrar acting hereunder.

                                       42
<PAGE>

  Section 5.2  Certain Rights of Trustee.

          Subject to the provisions of Section 5.1 and subject to Section 315(a)
through (d) of the TIA:

               (1) The Trustee may rely on any document believed by it to be
          genuine and to have been signed or presented by the proper person.
          The Trustee need not investigate any fact or matter stated in the
          document.

               (2) Before the Trustee acts or refrains from acting, it may
          require an Officers' Certificate or an Opinion of Counsel, or both.
          The Trustee shall not be liable for any action it takes or omits to
          take in good faith in reliance on the Officers' Certificate or Opinion
          of Counsel.

               (3) The Trustee may act through attorneys and agents and shall
          not be responsible for the misconduct or negligence of any attorney or
          agent appointed with due care.

               (4) The Trustee shall not be liable for any action taken or
          omitted to be taken by it in good faith which it believed to be
          authorized or within the discretion or rights or powers conferred upon
          it by this Indenture, unless the Trustee's conduct constitutes
          negligence.

               (5) The Trustee may consult with counsel of its selection and the
          advice of such counsel as to matters of law shall be full and complete
          authorization and protection in respect of any action taken, omitted
          or suffered by it hereunder in good faith and in accordance with the
          advice or opinion of such counsel.

               (6) Unless otherwise specifically provided in this Indenture, any
          demand, request, direction or notice from the Company shall be
          sufficient if signed by an Officer of the Company.

               (7) The permissive rights of the Trustee to do things enumerated
          in this Indenture shall not be construed as a duty unless so specified
          herein.

  Section 5.3  Individual Rights of Trustee.

          The Trustee in its individual or any other capacity may become the
owner or pledgee of Securities and may otherwise deal with the Company or any
Affiliate of the Company with the same rights it would have if it were not
Trustee.  However, in the event that the Trustee acquires any conflicting
interest (as such term is defined in Section 310(b) of the TIA), it must
eliminate such conflict within 90 days, apply to the SEC for permission to
continue as trustee (to the extent permitted under Section 310(b) of the TIA) or
resign.  Any agent may do the same with like rights and duties.  The Trustee is
also subject to Sections 5.11 and 5.12.

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<PAGE>

  Section 5.4  Money Held in Trust.

          Money held by the Trustee in trust hereunder need not be segregated
from other funds except to the extent required by law.  The Trustee shall be
under no liability for interest on any money received by it hereunder except as
otherwise expressly agreed with the Company.

  Section 5.5  Trustee's Disclaimer.

          The recitals contained herein and in the Securities (except for those
in the certificate of authentication) shall be taken as the statements of the
Company, and the Trustee assumes no responsibility for their correctness.  The
Trustee makes no representations as to the validity, sufficiency or priority of
this Indenture or of the Securities.  The Trustee shall not be accountable for
the use or application by the Company of Securities or the proceeds thereof.

  Section 5.6  Notice of Defaults.

          Within 90 days after the occurrence of any Default or Event of Default
hereunder of which the Trustee has received written notice, the Trustee shall
give notice to Holders pursuant to Section 14.2, unless such Default or Event of
Default shall have been cured or waived; provided, however, that, except in the
case of a Default or Event of Default in the payment of the principal of or
premium, if any, or interest (including Additional Amounts, if any), or in the
payment of any redemption or repurchase obligation on any Security, the Trustee
shall be protected in withholding such notice if and so long as Responsible
Officers of the Trustee in good faith determine that the withholding of such
notice is in the interest of the Holders.

  Section 5.7  Reports by Trustee to Holders.

          The Trustee shall transmit to Holders such reports concerning the
Trustee and its actions under this Indenture as may be required by Section 313
of the TIA at the times and in the manner provided by the TIA.

          A copy of each report at the time of its mailing to Holders shall be
filed with the SEC, if required, and each stock exchange, if any, on which the
Securities are listed.  The Company shall promptly notify the Trustee when the
Securities become listed on any stock exchange.

  Section 5.8  Compensation and Indemnification.

          The Company covenants and agrees to pay to the Trustee from time to
time, and the Trustee shall be entitled to, reasonable compensation (which shall
not be limited by any provision of law in regard to the compensation of a
trustee of an express trust) and the Company covenants and agrees to pay or
reimburse the Trustee upon its request for all reasonable expenses,
disbursements and advances incurred or made by or on behalf of it in accordance
with any of the provisions of this Indenture (including the reasonable
compensation and the expenses and disbursements of its counsel and of all agents
and other persons not regularly in its employ), except to the extent that any
such expense, disbursement or advance is due to its negligence or bad faith.
When the Trustee incurs expenses or renders services in connection with an Event
of

                                       44
<PAGE>

Default specified in Section 4.1, the expenses (including the reasonable charges
and expenses of its counsel) and the compensation for the services are intended
to constitute expenses of administration under any bankruptcy law. The Company
also covenants to indemnify the Trustee and its officers, directors, employees
and agents for, and to hold such Persons harmless against, any loss, liability
or expense incurred by them, arising out of or in connection with the acceptance
or administration of this Indenture or the trusts hereunder or the performance
of their duties hereunder, including the costs and expenses of defending
themselves against or investigating any claim of liability in the premises,
except to the extent that any such loss, liability or expense was due to the
negligence or willful misconduct of such Persons. The obligations of the Company
under this Section 5.8 to compensate and indemnify the Trustee and its officers,
directors, employees and agents and to pay or reimburse such Persons for
expenses, disbursements and advances shall constitute additional indebtedness
hereunder and shall survive the satisfaction and discharge of this Indenture or
the earlier resignation or removal of the Trustee. Such additional indebtedness
shall be a lien prior to that of the Securities upon all property and funds held
or collected by the Trustee as such, except funds held in trust for the benefit
of the Holders of particular Securities, and the Securities are hereby
subordinated to such senior claim. "Trustee" for purposes of this Section 5.8
shall include any predecessor Trustee, but the negligence or willful misconduct
of any Trustee shall not affect the indemnification of any other Trustee.

  Section 5.9  Replacement of Trustee.

          A resignation or removal of the Trustee and appointment of a successor
Trustee shall become effective only upon the successor Trustee's acceptance of
appointment as provided in this Section 5.9.

          The Trustee may resign and be discharged from the trust hereby created
by so notifying the Company in writing.  The Holders of at least a majority in
aggregate principal amount of Outstanding Securities may remove the Trustee by
so notifying the Trustee and the Company in writing.  The Company must remove
the Trustee if:

          (i)    the Trustee fails to comply with Section 5.10 or Section 310 of
     the TIA;

          (ii)   the Trustee becomes incapable of acting;

          (iii)  the Trustee is adjudged a bankrupt or an insolvent or an order
     for relief is entered with respect to the Trustee under any Bankruptcy Law;
     or

          (iv)   a Custodian or public officer takes charge of the Trustee or
     its property.

          If the Trustee resigns or is removed or if a vacancy exists in the
office of the Trustee for any reason, the Company shall promptly appoint a
successor Trustee.  The Trustee shall be entitled to payment of its fees and
reimbursement of its expenses while acting as Trustee.  Within one year after
the successor Trustee takes office, the Holders of at least a majority in
aggregate principal amount of Outstanding Securities may appoint a successor
Trustee to replace the successor Trustee appointed by the Company.

                                       45
<PAGE>

          Any Holder may petition any court of competent jurisdiction for the
removal of the Trustee and the appointment of a successor Trustee if the Trustee
fails to comply with Section 5.10.

          If an instrument of acceptance by a successor Trustee shall not have
been delivered to the Trustee within 30 days after the giving of such notice of
resignation or removal, the resigning or removed Trustee, as the case may be,
may petition, at the expense of the Company, any court of competent jurisdiction
for the appointment of a successor Trustee.

          A successor Trustee shall deliver a written acceptance of its
appointment to the retiring Trustee and to the Company.  Thereupon the
resignation or removal of the retiring Trustee shall become effective, and the
successor Trustee shall have all the rights, powers and duties of the Trustee
under this Indenture.  The Company shall issue a notice of the successor
Trustee's succession to the Holders.  Upon payment of its charges, the retiring
Trustee shall promptly transfer all property held by it as Trustee to the
successor Trustee, subject nevertheless to its lien, if any, provided for in
Section 5.8.  Notwithstanding replacement of the Trustee pursuant to this
Section 5.9, the Company's obligations under Section 5.8 shall continue for the
benefit of the retiring Trustee with respect to expenses, losses and liabilities
incurred by it prior to such replacement.

  Section 5.10 Successor Trustee by Merger, Etc.

          Subject to Section 5.11, if the Trustee consolidates with, merges or
converts into, or transfers all or substantially all of its corporate trust
business to, another Person, corporation or national banking association, the
successor entity without any further act shall be the successor Trustee as to
the Securities.

  Section 5.11 Corporate Trustee Required; Eligibility.

          The Trustee shall at all times satisfy the requirements of Section
310(a)(1), (2) and (5) of the TIA.  The Trustee shall at all times have (or, in
the case of a corporation included in a bank holding company system, the related
bank holding company shall at all times have), a combined capital and surplus of
at least $25 million as set forth in its (or its related bank holding company's)
most recent published annual report of condition.  The Trustee is subject to
Section 310(b) of the TIA.

  Section 5.12 Collection of Claims Against the Company.

          The Trustee is subject to Section 311(a) of the TIA, excluding any
creditor relationship listed in Section 311(b) of the TIA.  A Trustee who has
resigned or been removed shall be subject to Section 311(a) of the TIA to the
extent indicated therein.

                                       46
<PAGE>

                                   ARTICLE 6

             CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE

  Section 6.1  Company May Consolidate, Etc., Only on Certain Terms.

          The Company shall not consolidate with or merge into any other Person
or convey, transfer or lease its properties and assets substantially as an
entirety to any Person, and the Company shall not permit any Person to
consolidate with or merge into the Company or convey, transfer or lease its
properties and assets substantially as an entirety to the Company, unless:

               (1) in the event that the Company shall consolidate with or merge
          into another Person or convey, transfer or lease its properties and
          assets substantially as an entirety to any Person, the Person formed
          by such consolidation or into which the Company is merged or the
          Person which acquires by conveyance or transfer, or which leases, the
          properties and assets of the Company substantially as an entirety
          shall be a corporation, limited liability company, partnership or
          trust organized and validly existing under the laws of the United
          States of America, any State thereof or the District of Columbia and,
          if the entity surviving such transaction or transferee entity is not
          the Company, then such surviving or transferee entity shall expressly
          assume, by an indenture supplemental hereto, executed and delivered to
          the Trustee, in form satisfactory to the Trustee, the due and punctual
          payment of the principal of and premium, if any and interest
          (including Additional Amounts, if any), on all the Securities and the
          performance of every covenant of this Indenture on the part of the
          Company to be performed or observed and shall have provided for
          conversion rights in accordance with Section 12.11;

               (2) at the time of consummation of such transaction, no Event of
          Default, and no event which, after notice or lapse of time or both,
          would become an Event of Default, shall have happened and be
          continuing; and

               (3) the Company shall have delivered to the Trustee an Officers'
          Certificate and an Opinion of Counsel, each stating that such
          consolidation, merger, conveyance, transfer or lease and, if a
          supplemental indenture is required in connection with such
          transaction, such supplemental indenture, comply with this Article and
          that all conditions precedent herein provided for relating to such
          transaction have been complied with.

  Section 6.2  Successor Corporation Substituted.

          Upon any consolidation or merger by the Company with or into any other
corporation or any conveyance, transfer or lease of the properties and assets of
the Company substantially as an entirety to any Person, in accordance with
Section 6.1, the successor corporation formed by such consolidation or into
which the Company is merged or to which such conveyance, transfer or lease is
made shall succeed to, and be substituted for, and may exercise

                                       47
<PAGE>

every right and power of, the Company under this Indenture with the same effect
as if such successor corporation had been named as the Company herein, and
thereafter, except in the case of a lease to another Person, the predecessor
corporation shall be relieved of all obligations and covenants under this
Indenture and the Securities.

                                   ARTICLE 7

                      AMENDMENTS, SUPPLEMENTS AND WAIVERS

  Section 7.1  Without Consent of Holders of Securities.

          Without the consent of any Holders of Securities, the Company, when
authorized by a Board Resolution, and the Trustee, at any time and from time to
time, may amend this Indenture and the Securities to:

          (a) add to the covenants of the Company for the benefit of the Holders
  of Securities;

          (b) surrender any right or power herein conferred upon the Company;

          (c) make provision with respect to the conversion rights of Holders of
  Securities pursuant to Section 12.11;

          (d) provide for the assumption of the Company's obligations to the
  Holders of Securities in the case of a merger, consolidation, conveyance,
  transfer or lease pursuant to Article 6;

          (e) reduce the Conversion Price; provided, however, that such
  reduction in the Conversion Price shall not adversely affect the interest of
  the Holders of Securities (after taking into account tax and other
  consequences of such reduction);

          (f) comply with the requirements of the SEC in order to effect or
  maintain the qualification of this Indenture under the TIA;

          (g) make any changes or modifications to this Indenture necessary in
  connection with the registration of any Securities under the Securities Act as
  contemplated in the Registration Rights Agreement; provided, however, that
  such action pursuant to this clause (g) does not, in the good faith opinion of
  the Board of Directors (as evidenced by a Board Resolution) and the Trustee,
  adversely affect the interests of the Holders of Securities in any material
  respect;

          (h) cure any ambiguity, to correct or supplement any provision herein
  which may be inconsistent with any other provision herein or which is
  otherwise defective, or to make any other provisions with respect to matters
  or questions arising under this Indenture which the Company and the Trustee
  may deem necessary or desirable and which shall not be inconsistent with the
  provisions of this Indenture; provided, however, that such action pursuant to
  this clause (h) does not, in the good faith opinion of the

                                       48
<PAGE>

  Board of Directors (as evidenced by a Board Resolution) and the Trustee,
  adversely affect the interests of the Holders of Securities in any material
  respect;

          (i) add or modify any other provisions with respect to matters or
  questions arising under this Indenture which the Company and the Trustee may
  deem necessary or desirable and which shall not be inconsistent with the
  provisions of this Indenture; provided, however, that such action pursuant to
  this clause (i) does not, in the good faith opinion of the Board of Directors
  (as evidenced by a Board Resolution) and the Trustee, adversely affect the
  interests of the Holders of Securities in any material respect; or

          (j) make provision for the establishment of a book-entry system, in
  which Holders would have the option to participate, for the clearance and
  settlement of transactions in Securities originally issued in definitive form.

  Section 7.2  With Consent of Holders of Securities.

          Except as provided below in this Section 7.2, this Indenture or the
Securities may be amended or supplemented, and noncompliance in any particular
instance with any provision of this Indenture or the Securities may be waived,
in each case (i) with the written consent of the Holders of at least a majority
in aggregate principal amount of the Outstanding Securities or (ii) by the
adoption of a resolution, at a meeting of Holders of the Outstanding Securities
at which a quorum is present, by the Holders of a majority in aggregate
principal amount of the Outstanding Securities represented at such meeting.

          Without the written consent or the affirmative vote of each Holder of
Securities affected thereby, an amendment or waiver under this Section 7.2 may
not:

          (a) change the Stated Maturity of the principal of, or any installment
  of interest (including Additional Amounts, if any) on, any Security;

          (b) reduce the principal amount of, or premium, if any, on any
  Security;

          (c) reduce the Interest Rate or interest (including Additional
  Amounts, if any) on any Security;

          (d) change the currency of payment of principal of, premium, if any,
  or interest (including Additional Amounts, if any) on any Security;

          (e) impair the right of any Holder to institute suit for the
  enforcement of any payment in or with respect to any Security;

          (f) modify the obligation of the Company to maintain an office or
  agency in The City of New York pursuant to Section 9.2;

          (g) except as permitted by Section 12.11, adversely affect the
  Repurchase Right or the right to convert any Security as provided in
  Article 12;

                                       49
<PAGE>

          (h)  modify the provisions in Article 13 relating to the subordination
  of the Securities in a manner adverse to the Holders of Securities;

          (i)  modify the provisions in Article 10 relating to the redemption of
  the Securities in a manner adverse to the Holders of Securities;

          (j)  modify any of the provisions of this Section, Section 4.4 or
  Section 14.11, except to increase any percentage contained herein or therein
  or to provide that certain other provisions of this Indenture cannot be
  modified or waived without the consent of the Holder of each Outstanding
  Security affected thereby; or

          (k)  reduce the requirements of Section 8.4 for quorum or voting, or
  reduce the percentage in aggregate principal amount of the Outstanding
  Securities the consent of whose Holders is required for any such supplemental
  indenture or the consent of whose Holders is required for any waiver provided
  for in this Indenture.

          It shall not be necessary for any Act of Holders of Securities under
this Section 7.2 to approve the particular form of any proposal supplemental
indenture, but it shall be sufficient if such Act shall approve the substance
thereof.

  Section 7.3  Compliance with Trust Indenture Act.

          Every amendment to this Indenture or the Securities shall be set forth
in a supplemental indenture that complies with the TIA as then in effect.

  Section 7.4  Revocation of Consents and Effect of Consents or Votes.

          Until an amendment, supplement or waiver becomes effective, a written
consent to it by a Holder is a continuing consent by the Holder and every
subsequent Holder of a Security or portion of a Security that evidences the same
debt as the consenting Holder's Security, even if notation of the consent is not
made on any Security; provided, however, that unless a record date shall have
been established, any such Holder or subsequent Holder may revoke the consent as
to its Security or portion of a Security if the Trustee receives written notice
of revocation before the date the amendment, supplement or waiver becomes
effective.

          An amendment, supplement or waiver becomes effective on receipt by the
Trustee of written consents from or affirmative votes by, as the case may be,
the Holders of the requisite percentage of aggregate principal amount of the
Outstanding Securities, and thereafter shall bind every Holder of Securities;
provided, however, if the amendment, supplement or waiver makes a change
described in any of the clauses (a) through (k) of Section 7.2, the amendment,
supplement or waiver shall bind only each Holder of a Security which has
consented to it or voted for it, as the case may be, and every subsequent Holder
of a Security or portion of a Security that evidences the same indebtedness as
the Security of the consenting or affirmatively voting Holder, as the case may
be.

  Section 7.5  Notation on or Exchange of Securities.

          If an amendment, supplement or waiver changes the terms of a Security:

                                       50
<PAGE>

          (a) the Trustee may require the Holder of a Security to deliver such
  Securities to the Trustee, the Trustee may place an appropriate notation on
  the Security about the changed terms and return it to the Holder and the
  Trustee may place an appropriate notation on any Security thereafter
  authenticated; or

          (b) if the Company or the Trustee so determines, the Company in
  exchange for the Security shall issue and the Trustee shall authenticate a new
  Security that reflects the changed terms.

          Failure to make the appropriate notation or issue a new Security shall
  not affect the validity and effect of such amendment, supplement or waiver.

  Section 7.6  Trustee to Sign Amendment, Etc.

          The Trustee shall sign any amendment authorized pursuant to this
Article 7 if the amendment does not adversely affect the rights, duties,
liabilities or immunities of the Trustee.  If the amendment does adversely
affect the rights, duties, liabilities or immunities of the Trustee, the Trustee
may but need not sign it.  In signing or refusing to sign such amendment, the
Trustee shall be entitled to receive and shall be fully protected in relying
upon an Officers' Certificate and an Opinion of Counsel as conclusive evidence
that such amendment is authorized or permitted by this Indenture.

                                   ARTICLE 8

                       MEETING OF HOLDERS OF SECURITIES

  Section 8.1  Purposes for Which Meetings May Be Called.

          A meeting of Holders of Securities may be called at any time and from
time to time pursuant to this Article to make, give or take any request, demand,
authorization, direction, notice, consent, waiver or other action provided by
this Indenture to be made, given or taken by Holders of Securities.

  Section 8.2  Call Notice and Place of Meetings.

          (a) The Trustee may at any time call a meeting of Holders of
Securities for any purpose specified in Section 8.1, to be held at such time and
at such place in The City of New York.  Notice of every meeting of Holders of
Securities, setting forth the time and the place of such meeting and in general
terms the action proposed to be taken at such meeting, shall be given, in the
manner provided in Section 14.2, not less than 21 nor more than 180 days prior
to the date fixed for the meeting.

          (b) In case at any time the Company, pursuant to a Board Resolution,
or the Holders of at least 10% in principal amount of the Outstanding Securities
shall have requested the Trustee to call a meeting of the Holders of Securities
for any purpose specified in Section 8.1, by written request setting forth in
reasonable detail the action proposed to be taken at the meeting, and the
Trustee shall not have made the first publication of the notice of such meeting
within 21 days after receipt of such request or shall not thereafter proceed to
cause the meeting to

                                       51
<PAGE>

be held as provided herein, then the Company or the Holders of Securities in the
amount specified, as the case may be, may determine the time and the place in
The City of New York for such meeting and may call such meeting for such
purposes by giving notice thereof as provided in paragraph (a) of this Section
8.2.

  Section 8.3  Persons Entitled to Vote at Meetings.

          To be entitled to vote at any meeting of Holders of Securities, a
Person shall be (a) a Holder of one or more Outstanding Securities, or (b) a
Person appointed by an instrument in writing as proxy for a Holder or Holders of
one or more Outstanding Securities by such Holder or Holders.  The only Persons
who shall be entitled to be present or to speak at any meeting of Holders shall
be the Persons entitled to vote at such meeting and their counsel, any
representatives of the Trustee and its counsel and any representatives of the
Company and its counsel.

  Section 8.4  Quorum; Action.

          The Persons entitled to vote a majority in principal amount of the
Outstanding Securities shall constitute a quorum.  In the absence of a quorum
within 30 minutes of the time appointed for any such meeting, the meeting shall,
if convened at the request of Holders of Securities, be dissolved.  In any other
case, the meeting may be adjourned for a period of not less than 10 days as
determined by the chairman of the meeting prior to the adjournment of such
meeting.  In the absence of a quorum at any such adjourned meeting, such
adjourned meeting may be further adjourned for a period of not less than 10 days
as determined by the chairman of the meeting prior to the adjournment of such
adjourned meeting.  Notice of the reconvening of any adjourned meeting shall be
given as provided in Section 8.2(a), except that such notice need be given only
once and not less than five days prior to the date on which the meeting is
scheduled to be reconvened.  Notice of the reconvening of an adjourned meeting
shall state expressly the percentage of the principal amount of the Outstanding
Securities which shall constitute a quorum.

          Subject to the foregoing, at the reconvening of any meeting adjourned
for a lack of a quorum, the Persons entitled to vote 25% in principal amount of
the Outstanding Securities at the time shall constitute a quorum for the taking
of any action set forth in the notice of the original meeting.

          At a meeting or an adjourned meeting duly reconvened and at which a
quorum is present as aforesaid, any resolution and all matters (except as
limited by the proviso to Section 7.2) shall be effectively passed and decided
if passed or decided by the Persons entitled to vote not less than a majority in
principal amount of Outstanding Securities represented and voting at such
meeting.

          Any resolution passed or decisions taken at any meeting of Holders of
Securities duly held in accordance with this Section shall be binding on all the
Holders of Securities, whether or not present or represented at the meeting.

                                       52
<PAGE>

  Section 8.5  Determination of Voting Rights; Conduct and Adjournment of
Meetings.

          (a) Notwithstanding any other provisions of this Indenture, the
Trustee may make such reasonable regulations as it may deem advisable for any
meeting of Holders of Securities in regard to proof of the holding of Securities
and of the appointment of proxies and in regard to the appointment and duties of
inspectors of votes, the submission and examination of proxies, certificates and
other evidence of the right to vote, and such other matters concerning the
conduct of the meeting as it shall deem appropriate.  Except as otherwise
permitted or required by any such regulations, the holding of Securities shall
be proved in the manner specified in Section 1.3 and the appointment of any
proxy shall be proved in the manner specified in Section 1.3.  Such regulations
may provide that written instruments appointing proxies, regular on their face,
may be presumed valid and genuine without the proof specified in Section 1.3 or
other proof.

          (b) The Trustee shall, by an instrument in writing, appoint a
temporary chairman (which may be the Trustee) of the meeting, unless the meeting
shall have been called by the Company or by Holders of Securities as provided in
Section 8.2(b), in which case the Company or the Holders of Securities calling
the meeting, as the case may be, shall in like manner appoint a temporary
chairman.  A permanent chairman and a permanent secretary of the meeting shall
be elected by vote of the Persons entitled to vote a majority in principal
amount of the Outstanding Securities represented at the meeting.

          (c) At any meeting, each Holder of a Security or proxy shall be
entitled to one vote for each $1,000 principal amount of Securities held or
represented by him; provided, however, that no vote shall be cast or counted at
any meeting in respect of any Security challenged as not Outstanding and ruled
by the chairman of the meeting to be not Outstanding.  The chairman of the
meeting shall have no right to vote, except as a Holder of a Security or proxy.

          (d) Any meeting of Holders of Securities duly called pursuant to
Section 8.2 at which a quorum is present may be adjourned from time to time by
Persons entitled to vote a majority in principal amount of the Outstanding
Securities represented at the meeting, and the meeting may be held as so
adjourned without further notice.

  Section 8.6  Counting Votes and Recording Action of Meetings.

          The vote upon any resolution submitted to any meeting of Holders of
Securities shall be by written ballots on which shall be subscribed the
signatures of the Holders of Securities or of their representatives by proxy and
the principal amounts and serial numbers of the Outstanding Securities held or
represented by them.  The permanent chairman of the meeting shall appoint two
inspectors of votes who shall count all votes cast at the meeting for or against
any resolution and who shall make and file with the secretary of the meeting
their verified written reports in duplicate of all votes cast at the meeting.  A
record, at least in duplicate, of the proceedings of each meeting of Holders of
Securities shall be prepared by the secretary of the meeting and there shall be
attached to said record the original reports of the inspectors of votes on any
vote by ballot taken thereat and affidavits by one or more Persons having
knowledge of

                                       53
<PAGE>

the facts setting forth a copy of the notice of the meeting and showing that
said notice was given as provided in Section 8.2 and, if applicable, Section
8.4. Each copy shall be signed and verified by the affidavits of the permanent
chairman and secretary of the meeting and one such copy shall be delivered to
the Company and another to the Trustee to be preserved by the Trustee, the
latter to have attached thereto the ballots voted at the meeting. Any record so
signed and verified shall be conclusive evidence of the matters therein stated.

                                   ARTICLE 9

                                   COVENANTS

  Section 9.1  Payment of Principal, Premium and Interest.

          The Company will duly and punctually pay the principal of and premium,
if any, and interest (including Additional Amounts, if any) in respect of the
Securities in accordance with the terms of the Securities and this Indenture.
The Company will deposit or cause to be deposited with the Trustee as directed
by the Trustee, no later than the day of the Stated Maturity of any Security or
installment of interest (including Additional Amounts, if any), all payments so
due.

  Section 9.2  Maintenance of Offices or Agencies.

          The Company hereby appoints the Trustee's Corporate Trust Office as
its office in The City of New York, where Securities may be:

          (i)   presented or surrendered for payment;

          (ii)  surrendered for registration of transfer or exchange;

          (iii) surrendered for conversion;

and where notices and demands to or upon the Company in respect of the
Securities and this Indenture maybe served.

          The Company may at any time and from time to time vary or terminate
the appointment of any such office or appoint any additional offices for any or
all of such purposes; provided, however, that until all of the Securities have
been delivered to the Trustee for cancellation, or monies sufficient to pay the
principal of and premium, if any, and interest (including Additional Amounts, if
any) on the Securities have been made available for payment and either paid or
returned to the Company pursuant to the provisions of Section 9.3, the Company
will maintain in The City of New York, an office or agency where Securities may
be presented or surrendered for payment, where Securities may be surrendered for
registration of transfer or exchange, where Securities may be surrendered for
conversion and where notices and demands to or upon the Company in respect of
the Securities and this Indenture may be served.  The Company will give prompt
written notice to the Trustee, and notice to the Holders in accordance with
Section 14.2, of the appointment or termination of any such agents and of the
location and any change in the location of any such office or agency.

                                       54
<PAGE>

          If at any time the Company shall fail to maintain any such required
office or agency in The City of New York, or shall fail to furnish the Trustee
with the address thereof, presentations and surrenders may be made at, and
notices and demands may be served on, the Corporate Trust Office of the Trustee.

  Section 9.3  Corporate Existence.

          Subject to Article 6, the Company will do or cause to be done all
things necessary to preserve and keep in full force and effect its corporate
existence, rights (charter and statutory) and franchises; provided, however,
that the Company shall not be required to preserve any such right or franchise
if the Company determines that the preservation thereof is no longer desirable
in the conduct of the business of the Company and that the loss thereof is not
disadvantageous in any material respect to the Holders.

  Section 9.4  Maintenance of Properties.

          The Company will maintain and keep its properties and every part
thereof in such repair, working order and condition, and make or cause to be
made all such needful and proper repairs, renewals and replacements thereto, as
in the judgment of the Company are necessary in the interests of the Company;
provided, however, that nothing contained in this Section shall prevent the
Company from selling, abandoning or otherwise disposing of any of its properties
or discontinuing a part of its business from time to time if, in the judgment of
the Company, such sale, abandonment, disposition or discontinuance is advisable
and does not materially adversely affect the interests or business of the
Company.

  Section 9.5  Payment of Taxes and Other Claims.

          The Company will, and will cause any Significant Subsidiary to,
promptly pay and discharge or cause to be paid and discharged all material
taxes, assessments and governmental charges or levies lawfully imposed upon it
or upon its income or profits or upon any of its property, real or personal, or
upon any part thereof, as well as all material claims for labor, materials and
supplies which, if unpaid, might by law become a lien or charge upon its
property; provided, however, that neither the Company nor any Significant
Subsidiary shall be required to pay or discharge or cause to be paid or
discharged any such tax, assessment, charge, levy, or claim if the amount,
applicability or validity thereof shall currently be contested in good faith by
appropriate proceedings and if the Company or such Significant Subsidiary, as
the case may be, shall have set aside on its books reserves deemed by it
adequate with respect thereto.

  Section 9.6  Reports.

          (a) The Company shall deliver to the Trustee within 15 days after it
files them with the SEC copies of the annual reports and of the information,
documents, and other reports (or copies of such portions of any of the foregoing
as the SEC may by rules and regulations prescribe) which the Company is required
to file with the SEC pursuant to Section 13 or 15(d) of the Exchange Act;
provided, however, the Company shall not be required to deliver to the Trustee
any materials for which the Company has sought and received confidential
treatment by the SEC.  The Company also shall comply with the other provisions
of Section 314(a) of the TIA.

                                       55
<PAGE>

          (b) If at any time the Company is not subject to Section 13 or 15(d)
of the Exchange Act, upon the request of a Holder of a Security, the Company
will promptly furnish or cause to be furnished to such Holder or to a
prospective purchaser of such Security designated by such Holder, as the case
may be, the information, if any, required to be delivered by it pursuant to Rule
144A(d)(4) under the Securities Act to permit compliance with Rule 144A in
connection with the resale of such Security; provided, however, that the Company
shall not be required to furnish such information in connection with any request
made on or after the date which is two years from the later of the date such
security was last acquired from the Company or an "affiliate" (as defined under
Rule 144 under the Securities Act) of the Company.

  Section 9.7  Compliance Certificate.

          The Company shall deliver to the Trustee, within 120 days after the
end of each fiscal year of the Company (which as of the date hereof is December
31), an Officers' Certificate stating that in the course of the performance by
the signers of their duties as Officers of the Company, they would normally have
knowledge of any failure by the Company to comply with all conditions, or any
Default by the Company with respect to any covenants, under this Indenture, and
further stating whether or not they have knowledge of any such failure or
Default and, if so, specifying each such failure or Default and the nature
thereof.  In the event an Officer of the Company comes to have actual knowledge
of a Default, regardless of the date, the Company shall deliver an Officers'
Certificate to the Trustee specifying such Default and the nature and status
thereof.

  Section 9.8  Resale of Certain Securities.

          During the period of two years after the last date of original
issuance of any Securities, the Company shall not, and shall not permit any of
its "affiliates" (as defined under Rule 144 under the Securities Act) to, resell
any Securities, or shares of Common Stock issuable upon conversion of the
Securities, which constitute "restricted securities" under Rule 144, that are
acquired by any of them within the United States or to "U.S. persons" (as
defined in Regulation S) except pursuant to an effective registration statement
under the Securities Act or an applicable exemption therefrom.  The Trustee
shall have no responsibility or liability in respect of the Company's
performance of its agreement in the preceding sentence.

                                  ARTICLE 10

                           REDEMPTION OF SECURITIES

  Section 10.1 Provisional Redemption

          (a) The Company may, at its option, redeem the Securities in whole at
any time or in part from time to time, on any date prior to February 2, 2003,
upon notice as set forth in Section 10.5, at a Redemption Price (expressed as a
percentage of the principal amount) equal to 103.0000% of the principal amount
of the Securities called for such redemption, plus accrued and unpaid interest
to, but excluding, the Redemption Date specified in the notice in accordance
with Section 10.5, if:

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<PAGE>

              (1) the Shelf Registration Statement is effective and available
          for use and is expected to remain effective and available for use for
          the 30 days following such Redemption Date; and

              (2) the average of the high and low sale prices of the Company's
          Common Stock on any Trading Day (the "Current Market Value") equals or
          exceeds, for at least 20 Trading Days in any period of 30 consecutive
          Trading Days (ending on the Trading Day prior to the date the notice
          of redemption is mailed), the following percentages of the Conversion
          Price then in effect (the "Trigger Percentage") during the 12-month
          period beginning February 2 of the years indicated and ending February
          1 of the following year:

                                        Trigger Percentage
                                        ------------------

          2000                          170%

          2001                          160%

          2002                          150%

          (b) In addition to the Redemption Price, the Company shall pay, with
respect to any Securities called for redemption under this Section 10.1, an
additional payment (the "Interest Make-Whole Payment") equal to the sum of:

              (1) the Present Value of the aggregate amount of interest that
          would otherwise have accrued from the Redemption Date through February
          2, 2003 (the "Interest Make-Whole Period"); and

              (2) unpaid Additional Amounts on the Securities called for
          redemption, if any.

          "Present Value" shall be calculated by using the bond equivalent yield
on U.S. Government Obligations having a term nearest in length to that of the
Interest Make-Whole Period, as of the date of the notice of redemption.  The
Interest Make-Whole Payment shall be payable on all Securities called for
redemption, including those Securities which are converted into Common Stock
after the date of the notice of redemption but prior to the Redemption Date.

          (c) Subject to the fulfillment by the Company of the conditions set
forth in Section 11.2, the Company may elect to pay the Interest Make-Whole
Payment by delivering a number of shares of Common Stock equal to (i) the
Interest Make-Whole Payment divided by (ii) 95% of the average of the Trading
Prices per share of Common Stock for the five consecutive Trading Days
immediately preceding and including the third Trading Day prior to the
Redemption Date.

          (d) Any issuance of shares of Common Stock in respect of the Interest
Make-Whole Payment shall be deemed to have been effected immediately prior to
the close of business on the Redemption Date and the Person or Persons in whose
name or names any stock certificate or stock certificates representing shares of
Common Stock shall be issuable upon such redemption shall be deemed to have
become on the Redemption Date the holder or holders of

                                       57
<PAGE>

record of the shares represented thereby; provided, however, that any surrender
for redemption on a date when the stock transfer books of the Company shall be
closed shall constitute the Person or Persons in whose name or names the stock
certificate or stock certificates representing such shares are to be issued as
the holder or holders of record of the shares represented thereby for all
purposes at the opening of business on the next succeeding day on which such
stock transfer books are open. No payment or adjustment shall be made for
dividends or distributions on any Common Stock declared prior to the Redemption
Date.

          (e) No fractions of shares of Common Stock shall be issued upon
payment of the Interest Make-Whole Payment.  Instead of any fractional share of
Common Stock which would otherwise be issued, the Company shall pay a cash
adjustment in respect of such fraction (calculated to the nearest one-100th of a
share) in an amount equal to the same fraction of the Trading Price of the
Common Stock as of the Trading Day preceding the Redemption Date.

          (f) Any issuance and delivery of stock certificates representing
shares of Common Stock on payment of the Interest Make-Whole Payment shall be
made without charge to the Holder of Securities being redeemed or for any tax or
duty in respect of the issuance or delivery of such stock certificates or the
Securities represented thereby; provided, however, that the Company shall not be
required to pay any tax or duty which may be payable in respect of (i) income of
the Holder or (ii) any transfer involved in the issuance or delivery of stock
certificates representing shares of Common Stock in a name other than that of
the Holder of the Securities being redeemed, and no such issuance or delivery
shall be made unless the Persons requesting such issuance or delivery has paid
to the Company the amount of any such tax or duty or has established, to the
satisfaction of the Company, that such tax or duty has been paid.

  Section 10.2 Non-provisional Redemption.

          On or after February 2, 2003, the Company may, at its option, redeem
the Securities in whole at any time or in part from time to time, on any date
prior to maturity, upon notice as set forth in Section 10.5, at the Redemption
Price (expressed as percentages of the principal amount) set forth below if
redeemed on a Redemption Date occurring during the 12-month period beginning
February 2 of the years indicated and ending February 1 of the following year:

                                           Redemption Price
                                           ----------------

          2003                             103.0000%

          2004                             102.0000%

          2005                             101.0000%

          2006                             100.0000%

, plus any interest (including Additional Amounts, if any) accrued and unpaid
to, but excluding, the Redemption Date.

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<PAGE>

  Section 10.3  Notice to Trustee.

          If the Company elects to redeem Securities pursuant to the provisions
of Section 10.1 or 10.2, it shall notify the Trustee at least 30 days prior to
the intended Redemption Date of (i) such intended Redemption Date, (ii) the
principal amount of Securities to be redeemed and (iii) the CUSIP numbers of the
Securities to be redeemed.

  Section 10.4 Selection of Securities to Be Redeemed.

          If fewer than all the Securities are to be redeemed, the Trustee shall
select the particular Securities to be redeemed from the Outstanding Securities
by a method that complies with the requirements of any exchange on which the
Securities are listed, or, if the Securities are not listed on an exchange, on a
pro rata basis or by lot or in accordance with any other method the Trustee
considers fair and appropriate.  Securities and portions thereof  that the
Trustee selects shall be in amounts equal to the minimum authorized
denominations for Securities to be redeemed or any integral multiple thereof.

          If any Security selected for partial redemption is converted in part
before termination of the conversion right with respect to the portion of the
Security so selected, the converted portion of such Security shall be deemed to
be the portion selected for redemption; provided, however, that the Holder of
such Security so converted and deemed redeemed shall not be entitled to any
additional interest payment as a result of such deemed redemption than such
Holder would have otherwise been entitled to receive upon conversion of such
Security.  Securities which have been converted during a selection of Securities
to be redeemed may be treated by the Trustee as Outstanding for the purpose of
such selection.

          The Trustee shall promptly notify the Company and the Registrar in
writing of the Securities selected for redemption and, in the case of any
Securities selected for partial redemption, the principal amount thereof to be
redeemed.

          For all purposes of this Indenture, unless the context otherwise
requires, all provisions relating to the redemption of Securities shall relate,
in the case of any Securities redeemed or to be redeemed only in part, to the
portion of the principal amount of such Securities which has been or is to be
redeemed.

  Section 10.5 Notice of Redemption.

          Notice of redemption shall be given in the manner provided in Section
14.2 to the Holders of Securities to be redeemed.  Such notice shall be given
not less than 20 nor more than 60 days prior to the intended Redemption Date.

          All notices of redemption shall state:

               (1) such intended Redemption Date;

               (2) the Redemption Price and interest (including Additional
          Amounts, if any) accrued and unpaid to, but excluding, the Redemption
          Date, if any;

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<PAGE>

               (3) the Interest Make-Whole Payment, if any;

               (4) if fewer than all the Outstanding Securities are to be
          redeemed, the aggregate principal amount of Securities to be redeemed
          and the aggregate principal amount of Securities which will be
          Outstanding after such partial redemption;

               (5) that on the Redemption Date the Redemption Price, the
          Interest Make-Whole Payment, if any, and interest accrued and unpaid
          to, but excluding, the Redemption Date, if any, will become due and
          payable upon each such Security to be redeemed, and that interest
          (including Additional Amounts, if any) thereon shall cease to accrue
          on and after such date;

               (6) the Conversion Price, the date on which the right to convert
          the principal of the Securities to be redeemed will terminate and the
          places where such Securities may be surrendered for conversion;

               (7) the place or places where such Securities are to be
          surrendered for payment of the Redemption Price, accrued and unpaid
          interest, if any, and Interest Make-Whole Payment, if any;

               (8) whether the Interest Make-Whole Payment is to be paid in
          shares of Common Stock, and if so, that the Holder shall provide the
          name or names (with addresses) in which the stock certificate or stock
          certificates representing shares of Common Stock are to be issued upon
          surrender of the Securities; and

               (9) the CUSIP number of the Securities.

          The notice given shall specify the last date on which exchanges or
transfers of Securities may be made pursuant to Section 2.7, and shall specify
the serial numbers of Securities and the portions thereof called for redemption.

          Notice of redemption of Securities to be redeemed at the election of
the Company shall be given by the Company or, at the Company's request, by the
Trustee in the name of and at the expense of the Company.

  Section 10.6 Effect of Notice of Redemption.

          Notice of redemption having been given as provided in Section 10.5,
the Securities so to be redeemed shall, on the Redemption Date, become due and
payable at the Redemption Price therein specified and from and after such date
(unless the Company shall default in the payment of the Redemption Price and
accrued and unpaid interest) such Securities shall cease to bear interest.  Upon
surrender of any such Security for redemption in accordance with such notice,
such Security shall be paid by the Company at the Redemption Price; provided,
however, the installments of interest on Securities whose Stated Maturity is
prior to or on the Redemption Date shall be payable to the Holders of such
Securities, or one or more Predecessor Securities, registered as such on the
relevant Record Date according to their terms and the provisions of Section 2.7.

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<PAGE>

          If any Security called for redemption shall not be so paid upon
surrender thereof for redemption, the principal and premium, if any, shall,
until paid, bear interest from the Redemption Date at the Interest Rate.

  Section 10.7 Deposit of Redemption Price.

          Prior to or on any Redemption Date, the Company shall deposit with the
Trustee or with a Paying Agent an amount of money sufficient to pay the
Redemption Price, accrued and unpaid interest (including Additional Amounts, if
any), and Interest Make-Whole Payment, if any, in respect of all the Securities
to be redeemed on that Redemption Date, other than any Securities called for
redemption on that date which have been converted prior to the date of such
deposit, and accrued and unpaid interest, if any, on such Securities.

          If any Security called for redemption is converted, any money
deposited with the Trustee or with a Paying Agent or so segregated and held in
trust for the redemption of such Security shall (subject to any right of the
Holder of such Security or any Predecessor Security to receive interest as
provided in the fourth to last paragraph of Section 2.1) be paid to the Company
on Company Request or, if then held by the Company, shall be discharged from
such trust.

  Section 10.8 Securities Redeemed in Part.

          Any Security which is to be redeemed only in part shall be surrendered
at an office or agency of the Company designated for that purpose pursuant to
Section 9.2 (with, if the Company or the Trustee so requires, due endorsement
by, or a written instrument of transfer in form satisfactory to the Company and
the Trustee duly executed by, the Holder thereof or the Holder's attorney duly
authorized in writing), and the Company shall execute, and the Trustee shall
authenticate and deliver to the Holder of such Security without service charge,
a new Security or Securities of any authorized denomination as requested by such
Holder in aggregate principal amount equal to and in exchange for the unredeemed
portion of the principal of the Security so surrendered.

                                  ARTICLE 11

         REPURCHASE AT THE OPTION OF A HOLDER UPON A CHANGE OF CONTROL

  Section 11.1 Repurchase Right.

          In the event that a Change in Control shall occur, each Holder shall
have the right (the "Repurchase Right"), at the Holder's option, but subject to
the provisions of Section 11.2, to require the Company to repurchase, and upon
the exercise of such right the Company shall repurchase, all of such Holder's
Securities not theretofore called for redemption, or any portion of the
principal amount thereof that is equal to any integral multiple of $1,000
(provided that no single Security may be repurchased in part unless the portion
of the principal amount of such Security to be Outstanding after such repurchase
is equal to an integral multiple of $1,000), on the date (the "Repurchase Date")
that is 45 days after the date of the Company Notice given pursuant to Section
11.3 in connection with such Change of Control at a purchase price equal to

                                       61
<PAGE>

100% of the principal amount of the Securities to be repurchased (the
"Repurchase Price"), plus interest (including Additional Amounts, if any)
accrued and unpaid to, but excluding, the Repurchase Date; provided, however,
that installments of interest on Securities whose Stated Maturity is prior to or
on the Repurchase Date shall be payable to the Holders of such Securities, or
one or more Predecessor Securities, registered as such on the relevant Record
Date according to their terms and the provisions of Section 2.1.

          Subject to the fulfillment by the Company of the conditions set forth
in Section 11.2, the Company may elect to pay the Repurchase Price by delivering
a number of shares of Common Stock equal to (i) the Repurchase Price divided by
(ii) 95% of the average of the Trading Prices per share of Common Stock for the
five consecutive Trading Days immediately preceding and including the third
Trading Day prior to the Repurchase Date.

          Whenever in this Indenture (including Sections 2.2, 4.1(a) and 4.7) or
Exhibit A annexed hereto there is a reference, in any context, to the principal
---------
of any Security as of any time, such reference shall be deemed to include
reference to the Repurchase Price payable in respect to such Security to the
extent that such Repurchase Price is, was or would be so payable at such time,
and express mention of the Repurchase Price in any provision of this Indenture
shall not be construed as excluding the Repurchase Price in those provisions of
this Indenture when such express mention is not made; provided, however, that,
for the purposes of Article 13, such reference shall be deemed to include
reference to the Repurchase Price only to the extent the Repurchase Price is
payable in cash.

  Section 11.2 Conditions to the Company's Election to Pay the Repurchase Price
or an Interest Make-Whole Payment in Common Stock.

          The Company may, at its option, pay the Repurchase Price payable to
Holders pursuant to Section 11.1 or the Interest Make-Whole Payment payable to
Holders pursuant to Section 10.1(b) upon redemption of the Securities, in shares
of Common Stock, if the following conditions are satisfied:

          (a) The shares of Common Stock to be so issued:

               (i)  shall not require registration under any federal securities
          law before such shares may be freely transferable without being
          subject to any transfer restrictions under the Securities Act upon
          repurchase or redemption, as the case may be, or if such registration
          is required, such registration shall be completed and shall become
          effective prior to the Repurchase Date or the Redemption Date, as the
          case may be; and

               (ii) shall not require registration with, or approval of, any
          governmental authority under any state law or any other federal law
          before shares may be validly issued or delivered upon repurchase or
          redemption or if such registration is required or such approval must
          be obtained, such registration shall be completed or such approval
          shall be obtained prior to the Repurchase Date or Redemption Date, as
          the case may be.

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<PAGE>

          (b) The shares of Common Stock to be listed upon repurchase or
     redemption of Securities hereunder are, or shall have been, approved for
     listing on the Nasdaq National Market or the New York Stock Exchange or
     listed on another national securities exchange, in any case, prior to the
     Repurchase Date or the Redemption Date, as the case may be.

          (c) All shares of Common Stock which may be issued upon repurchase or
     redemption of Securities will be issued out of the Company's authorized but
     unissued Common Stock and will, upon issue, be duly and validly issued and
     fully paid and nonassessable and free of any preemptive or similar rights.

          (d) If any of the conditions set forth in clauses (a) through (c) of
     this Section 11.2 are not satisfied in accordance with the terms thereof,
     the Repurchase Price or the Interest Make-Whole Payment, as applicable,
     shall be paid by the Company only in cash.

     Section 11.3 Notices; Method of Exercising Repurchase Right, Etc.

          (a) Unless the Company shall have theretofore called for redemption
all of the Outstanding Securities, prior to or on the 30/th/ day after the
occurrence of a Change in Control, the Company, or, at the written request and
expense of the Company prior to or on the 30/th/ day after such occurrence, the
Trustee, shall give to all Holders of Securities notice, in the manner provided
in Section 14.2, of the occurrence of the Change of Control and of the
Repurchase Right set forth herein arising as a result thereof (the "Company
Notice").  The Company shall also deliver a copy of such notice of a Repurchase
Right to the Trustee.  Each notice of a Repurchase Right shall state:

               (1) the Repurchase Date;

               (2) the date by which the Repurchase Right must exercised;

               (3) the Repurchase Price and accrued and unpaid interest
          (including Additional Amounts, if any), if any;

               (4) whether the Repurchase Price shall be paid by the Company in
          cash or by delivery of shares of Common Stock;

               (5) a description of the procedure which a Holder must follow to
          exercise its Repurchase Right, and the place or places where such
          Securities, are to be surrendered for payment of the Repurchase Price
          and accrued and unpaid interest, if any;

               (6) that on the Repurchase Date the Repurchase Price and accrued
          and unpaid interest, if any, will become due and payable in cash upon
          each such Security designated by the Holder to be repurchased, and
          that interest thereon shall cease to accrue on and after said date;

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<PAGE>

               (7) the Conversion Rate then in effect, the date on which the
          right to convert the principal amount of the Securities to be
          repurchased will terminate and the place where such Securities may be
          surrendered for conversion, and

               (8) the place or places where such Securities, together with the
          Option to Elect Repayment Upon a Change of Control certificate
          included in Exhibit A annexed hereto are to be delivered for payment
                      ---------
          of the Repurchase Price and accrued and unpaid interest, if any.

          No failure of the Company to give the foregoing notices or defect
therein shall limit any Holder's right to exercise a Repurchase Right or affect
the validity of the proceedings for the repurchase of Securities.

          If any of the foregoing provisions or other provisions of this Article
11 are inconsistent with applicable law, such law shall govern.

          (b) To exercise its Repurchase Right, a Holder shall deliver to the
Trustee prior to or on the 30th day after the date of the Company Notice:

              (1) written notice of the Holder's exercise of such right, which
          notice shall set forth the name of the Holder, the principal amount of
          the Securities to be repurchased (and, if any Security is to be
          repurchased in part, the serial number thereof, the portion of the
          principal amount thereof to be repurchased) and a statement that an
          election to exercise the Repurchase Right is being made thereby, and,
          in the event that the Repurchase Price shall be paid in shares of
          Common Stock, the name or names (with addresses) in which the
          certificate or certificates for shares of Common Stock shall be
          issued; and

              (2) the Securities with respect to which the Repurchase Right is
          being exercised.

Such written notice shall be irrevocable, except that the right of the Holder to
convert the Securities with respect to which the Repurchase Right is being
exercised shall continue until the close of business on the Business Day
immediately preceding the Repurchase Date.

          (c) In the event a Repurchase Right shall be exercised in accordance
with the terms hereof, the Company shall pay or cause to be paid to the Trustee
the Repurchase Price in cash or shares of Common Stock, as provided above, for
payment to the Holder on the Repurchase Date or, if shares of Common Stock are
to be paid, as promptly after the Repurchase Date as practicable, together with
accrued and unpaid interest to, but excluding, the Repurchase Date payable in
cash with respect to the Securities as to which the Repurchase Right has been
exercised; provided, however, that installments of interest that mature prior to
or on the Repurchase Date shall be payable in cash to the Holders of such
Securities, or one or more Predecessor Securities, registered as such at the
close of business on the relevant Regular Record Date.

          (d) If any Security (or portion thereof) surrendered for repurchase
shall not be so paid on the Repurchase Date, the principal amount of such
Security (or portion thereof, as the

                                       64
<PAGE>

case may be) shall, until paid, bear interest to the extent permitted by
applicable law from the Repurchase Date at the Interest Rate, and each Security
shall remain convertible into Common Stock until the principal of such Security
(or portion thereof, as the case may be) shall have been paid or duly provided
for.

          (e) Any Security which is to be repurchased only in part shall be
surrendered to the Trustee (with, if the Company or the Trustee so requires, due
endorsement by, or a written instrument of transfer in form satisfactory to the
Company and the Trustee duly executed by the Holder thereof or his attorney duly
authorized in writing), and the Company shall execute, and the Trustee shall
authenticate and make available for delivery to the Holder of such Security
without service charge, a new Security or Securities, containing identical terms
and conditions, each in an authorized denomination in aggregate principal amount
equal to and in exchange for the unrepurchased portion of the principal of the
Security so surrendered.

          (f) Any issuance of shares of Common Stock in respect of the
Repurchase Price shall be deemed to have been effected immediately prior to the
close of business on the Repurchase Date and the Person or Persons in whose name
or names any stock certificate or stock certificates representing shares of
Common Stock shall be issuable upon such repurchase shall be deemed to have
become on the Repurchase Date the holder or holders of record of the shares
represented thereby; provided, however, that any surrender for repurchase on a
date when the stock transfer books of the Company shall be closed shall
constitute the Person or Persons in whose name or names the stock certificate or
stock certificates representing such shares are to be issued as the holder or
holders of record of the shares represented thereby for all purposes at the
opening of business on the next succeeding day on which such stock transfer
books are open.  No payment or adjustment shall be made for dividends or
distributions on any Common Stock issued upon repurchase of any Security
declared prior to the Repurchase Date.

          (g) No fractions of shares of Common Stock shall be issued upon
repurchase of any Security or Securities.  If more than one Security shall be
repurchased from the same Holder and the Repurchase Price shall be payable in
shares of Common Stock, the number of full shares which shall be issued upon
such repurchase shall be computed on the basis of the aggregate principal amount
of the Securities (or specified portions thereof) to be so repurchased.  Instead
of any fractional share of Common Stock which would otherwise be issued on the
repurchase of any Security or Securities (or specified portions thereof), the
Company shall pay a cash adjustment in respect of such fraction (calculated to
the nearest one-100th of a share) in an amount equal to the same fraction of the
Trading Price of the Common Stock as of the Trading Day preceding the Repurchase
Date.

          (h) Any issuance and delivery of stock certificates representing
shares of Common Stock on repurchase of Securities shall be made without charge
to the Holder of Securities being repurchased for such stock certificates or for
any tax or duty in respect of the issuance or delivery of such stock
certificates or the Securities represented thereby; provided, however, that the
Company shall not be required to pay any tax or duty which may be payable in
respect of (i) income of the Holder or (ii) any transfer involved in the
issuance or delivery of stock certificates representing shares of Common Stock
in a name other than that of the Holder of the Securities being repurchased, and
no such issuance or delivery shall be made unless the Person requesting such
issuance or delivery has paid to the Company the amount of any such tax

                                       65
<PAGE>

or duty or has established, to the satisfaction of the Company, that such tax or
duty has been paid.

          (i) All Securities delivered for repurchase shall be delivered to the
Trustee to be canceled at the direction of the Trustee, which shall dispose of
the same as provided in Section 2.15.

                                  ARTICLE 12

                           CONVERSION OF SECURITIES

  Section 12.1 Conversion Right and Conversion Price.

          Subject to and upon compliance with the provisions of this Article, at
the option of the Holder thereof, any Security or any portion of the principal
amount thereof which is an integral multiple of $1,000 may be converted at the
principal amount thereof, or of such portion thereof, into duly authorized,
fully paid and nonassessable shares of Common Stock, at the Conversion Price,
determined as hereinafter provided, in effect at the time of conversion.  Such
conversion right shall expire at the close of business on the Business Day
immediately preceding February 2, 2007.

          In case a Security or portion thereof is called for redemption, such
conversion right in respect of the Security or the portion so called, shall
expire at the close of business on the second Business Day preceding the
Redemption Date, unless the Company defaults in making the payment due upon
redemption.  In the case of a Change of Control for which the Holder exercises
its Repurchase Right with respect to a Security or portion thereof, such
conversion right in respect of the Security or portion thereof shall expire at
the close of business on the Business Day immediately preceding the Repurchase
Date.

          The price at which shares of Common Stock shall be delivered upon
conversion (the "Conversion Price") shall be initially equal to $127.6550 per
share of Common Stock.  The Conversion Price shall be adjusted in certain
instances as provided in paragraphs (a), (b), (c), (d), (e), (f), (h) and (1) of
Section 12.4.

  Section 12.2 Exercise of Conversion Right.

          To exercise the conversion right, the Holder of any Security to be
converted shall surrender such Security duly endorsed or assigned to the Company
or in blank, at the office of any Conversion Agent, accompanied by a duly signed
conversion notice substantially in the form attached to the Security to the
Company stating that the Holder elects to convert such Security or, if less than
the entire principal amount thereof is to be converted, the portion thereof to
be converted.

          Securities surrendered for conversion during the period from the close
of business on any Regular Record Date to the opening of business on the next
succeeding Interest Payment Date (except in the case of any Security whose
Maturity is prior to such Interest Payment Date) shall be accompanied by payment
in New York Clearing House funds or other funds acceptable

                                       66
<PAGE>

to the Company of an amount equal to the interest to be received on such
Interest Payment Date on the principal amount of Securities being surrendered
for conversion.

          Securities shall be deemed to have been converted immediately prior to
the close of business on the day of surrender of such Securities for conversion
in accordance with the foregoing provisions, and at such time the rights of the
Holders of such Securities as Holders shall cease, and the Person or Persons
entitled to receive the Common Stock issuable upon conversion shall be treated
for all purposes as the record holder or holders of such Common Stock at such
time.  As promptly as practicable on or after the conversion date, the Company
shall cause to be issued and delivered to such Conversion Agent a stock
certificate or stock certificates representing the number of full shares of
Common Stock issuable upon conversion of such Securities, together with payment
in lieu of any fraction of a share as provided in Section 12.3.

          In the case of any Security which is converted in part only, upon such
conversion the Company shall execute and the Trustee shall authenticate and
deliver to the Holder thereof, at the expense of the Company, a new Security or
Securities of authorized denominations in aggregate principal amount equal to
the unconverted portion of the principal amount of such Securities.

          If shares of Common Stock to be issued upon conversion of a Restricted
Security, or Securities to be issued upon conversion of a Restricted Security in
part only, are to be registered in a name other than that of the Holder of such
Restricted Security, such Holder must deliver to the Conversion Agent a
certificate in substantially the form set forth in the form of Security set
forth in Exhibit A annexed hereto, dated the date of surrender of such
         ---------
Restricted Security and signed by such Holder, as to compliance with the
restrictions on transfer applicable to such Restricted Security.  Neither the
Trustee nor any Conversion Agent, Registrar or Transfer Agent shall be required
to register in a name other than that of the Holder shares of Common Stock or
Securities issued upon conversion of any such Restricted Security not so
accompanied by a properly completed certificate.

          The Company hereby initially appoints the Trustee as the Conversion
Agent.

  Section 12.3 Fractions of Shares.

          No fractional shares of Common Stock shall be issued upon conversion
of any Security or Securities.  If more than one Security shall be surrendered
for conversion at one time by the same Holder, the number of full shares which
shall be issued upon conversion thereof shall be computed on the basis of the
aggregate principal amount of the Securities (or specified portions thereof) so
surrendered.  Instead of any fractional share of Common Stock which would
otherwise be issued upon conversion of any Security or Securities (or specified
portions thereof), the Company shall pay a cash adjustment in respect of such
fraction (calculated to the nearest one-100th of a share) in an amount equal to
the same fraction of the Trading Price of the Common Stock as of the Trading Day
preceding the date of conversion.

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<PAGE>

  Section 12.4 Adjustment of Conversion Price.

          The Conversion Price shall be subject to adjustment, calculated by the
Company, from time to time as follows:

          (a) In case the Company shall hereafter pay a dividend or make a
     distribution to all holders of the outstanding Common Stock in shares of
     Common Stock, the Conversion Price in effect at the opening of business on
     the date following the date fixed for the determination of stockholders
     entitled to receive such dividend or other distribution shall be reduced by
     multiplying such Conversion Price by a fraction:

              (i)   the numerator of which shall be the number of shares of
          Common Stock outstanding at the close of business on the Record Date
          (as defined in Section 12.4(g)) fixed for such determination; and

              (ii)  the denominator of which shall be the sum of such number of
          shares and the total number of shares constituting such dividend or
          other distribution.

     Such reduction shall become effective immediately after the opening of
     business on the day following the Record Date.  If any dividend or
     distribution of the type described in this Section 12.4(a) is declared but
     not so paid or made, the Conversion Price shall again be adjusted to the
     Conversion Price which would then be in effect if such dividend or
     distribution had not been declared.

          (b) In case the outstanding shares of Common Stock shall be subdivided
     into a greater number of shares of Common Stock, the Conversion Price in
     effect at the opening of business on the day following the day upon which
     such subdivision becomes effective shall be proportionately reduced, and
     conversely, in case outstanding shares of Common Stock shall be combined
     into a smaller number of shares of Common Stock, the Conversion Price in
     effect at the opening of business on the day following the day upon which
     such combination becomes effective shall be proportionately increased, such
     reduction or increase, as the case may be, to become effective immediately
     after the opening of business on the day following the day upon which such
     subdivision or combination becomes effective.

          (c) In case the Company shall issue rights or warrants (other than any
     rights or warrants referred to in Section 12.4(d)) to all holders of its
     outstanding shares of Common Stock entitling them to subscribe for or
     purchase shares of Common Stock (or securities convertible into Common
     Stock) at a price per share (or having a conversion price per share) less
     than the Current Market Price (as defined in Section 12.4(g)) on the Record
     Date fixed for the determination of stockholders entitled to receive such
     rights or warrants, the Conversion Price shall be adjusted so that the same
     shall equal the price determined by multiplying the Conversion Price in
     effect at the opening of business on the date after such Record Date by a
     fraction:

              (i)  the numerator of which shall be the number of shares of
          Common Stock outstanding at the close of business on the Record Date,
          plus the number of

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<PAGE>

          shares which the aggregate offering price of the total number of
          shares so offered for subscription or purchase (or the aggregate
          conversion price of the convertible securities so offered) would
          purchase at such Current Market Price; and

              (ii) the denominator of which shall be the number of shares of
          Common Stock outstanding on the close of business on the Record Date,
          plus the total number of additional shares of Common Stock so offered
          for subscription or purchase (or into which the convertible securities
          so offered are convertible).

     Such adjustment shall become effective immediately after the opening of
     business on the day following the Record Date fixed for determination of
     stockholders entitled to receive such rights or warrants.  To the extent
     that shares of Common Stock (or securities convertible into Common Stock)
     are not delivered pursuant to such rights or warrants, upon the expiration
     or termination of such rights or warrants, the Conversion Price shall be
     readjusted to the Conversion Price which would then be in effect had the
     adjustments made upon the issuance of such rights or warrants been made on
     the basis of the delivery of only the number of shares of Common Stock (or
     securities convertible into Common Stock) actually delivered.  In the event
     that such rights or warrants are not so issued, the Conversion Price shall
     again be adjusted to be the Conversion Price which would then be in effect
     if such date fixed for the determination of stockholders entitled to
     receive such rights or warrants had not been fixed.  In determining whether
     any rights or warrants entitle the holders to subscribe for or purchase
     shares of Common Stock at less than such Current Market Price, and in
     determining the aggregate offering price of such shares of Common Stock,
     there shall be taken into account any consideration received for such
     rights or warrants, the value of such consideration if other than cash, to
     be determined by the Board of Directors.

          (d) In case the Company shall, by dividend or otherwise, distribute to
     all holders of its Common Stock shares of any class of capital stock of the
     Company (other than any dividends or distributions to which Section 12.4(a)
     applies) or evidences of its indebtedness, cash or other assets, including
     securities, but excluding (1) any rights or warrants referred to in Section
     12.4(c), (2) any stock, securities or other property or assets (including
     cash) distributed in connection with a reclassification, change, merger,
     consolidation, statutory share exchange, combination, sale or conveyance to
     which Section 12.11 applies and (3) dividends and distributions paid
     exclusively in cash (the securities described in foregoing clauses (1), (2)
     and (3) hereinafter in this Section 12.4(d) called the "securities"), then,
     in each such case, subject to the second succeeding paragraph of this
     Section 12.4(d), the Conversion Price shall be reduced so that the same
     shall be equal to the price determined by multiplying the Conversion Price
     in effect immediately prior to the close of business on the Record Date (as
     defined in Section 12.4(g)) with respect to such distribution by a
     fraction:

              (i)  the numerator of which shall be the Current Market Price
          (determined as provided in Section 12.4(g)) on such date, less the
          fair market value (as determined by the Board of Directors, whose
          determination shall be conclusive and set forth in a Board Resolution)
          on such date of the portion of the securities so distributed
          applicable to one share of Common Stock (determined on

                                       69
<PAGE>

          the basis of the number of shares of the Common Stock outstanding on
          the Record Date); and

              (ii) the denominator of which shall be such Current Market Price.

     Such reduction shall become effective immediately prior to the opening of
     business on the day following the Record Date.  However, in the event that
     the then fair market value (as so determined) of the portion of the
     securities so distributed applicable to one share of Common Stock is equal
     to or greater than the Current Market Price on the Record Date, in lieu of
     the foregoing adjustment, adequate provision shall be made so that each
     Holder shall have the right to receive upon conversion of a Security (or
     any portion thereof) the amount of securities such Holder would have
     received had such Holder converted such Security (or portion thereof)
     immediately prior to such Record Date.  In the event that such dividend or
     distribution is not so paid or made, the Conversion Price shall again be
     adjusted to be the Conversion Price which would then be in effect if such
     dividend or distribution had not been declared.

               If the Board of Directors determines the fair market value of any
     distribution for purposes of this Section 12.4(d) by reference to the
     actual or when issued trading market for any securities comprising all or
     part of such distribution, it must in doing so consider the prices in such
     market over the same period (the "Reference Period") used in computing the
     Current Market Price pursuant to Section 12.4(g) to the extent possible,
     unless the Board of Directors in a Board Resolution determines in good
     faith that determining the fair market value during the Reference Period
     would not be in the best interest of the Holders.

               Rights or warrants distributed by the Company to all holders of
     Common Stock entitling the holders thereof to subscribe for or purchase
     shares of the Company's capital stock (either initially or under certain
     circumstances), which rights or warrants, until the occurrence of a
     specified event or events ("Trigger Event"):

               (i)   are deemed to be transferred with such shares of Common
          Stock;

               (ii)  are not exercisable; and

               (iii) are also issued in respect of future issuances of Common
          Stock;

     shall be deemed not to have been distributed for purposes of this Section
     12.4(d) (and no adjustment to the Conversion Price under this Section
     12.4(d) will be required) until the occurrence of the earliest Trigger
     Event.  If such right or warrant is subject to subsequent events, upon the
     occurrence of which such right or warrant shall become exercisable to
     purchase different securities, evidences of indebtedness or other assets or
     entitle the holder to purchase a different number or amount of the
     foregoing or to purchase any of the foregoing at a different purchase
     price, then the occurrence of each such event shall be deemed to be the
     date of issuance and record date with respect to a new right or warrant
     (and a termination or expiration of the existing right or warrant without
     exercise by the holder thereof).  In addition, in the event of any
     distribution (or deemed distribution) of rights or warrants, or any Trigger
     Event or other event (of the type

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<PAGE>

     described in the preceding sentence) with respect thereto, that resulted in
     an adjustment to the Conversion Price under this Section 12.4(d):

               (1) in the case of any such rights or warrants which shall all
          have been redeemed or repurchased without exercise by any holders
          thereof, the Conversion Price shall be readjusted upon such final
          redemption or repurchase to give effect to such distribution or
          Trigger Event, as the case may be, as though it were a cash
          distribution, equal to the per share redemption or repurchase price
          received by a holder of Common Stock with respect to such rights or
          warrants (assuming such holder had retained such rights or warrants),
          made to all holders of Common Stock as of the date of such redemption
          or repurchase; and

               (2) in the case of such rights or warrants all of which shall
          have expired or been terminated without exercise, the Conversion Price
          shall be readjusted as if such rights and warrants had never been
          issued.

          For purposes of this Section 12.4(d) and Sections 12.4(a), 12.4(b) and
          12.4(c), any dividend or distribution to which this Section 12.4(d) is
          applicable that also includes shares of Common Stock, a subdivision or
          combination of Common Stock to which Section 12.4(c) applies, or
          rights or warrants to subscribe for or purchase shares of Common Stock
          to which Section 12.4(c) applies (or any combination thereof), shall
          be deemed instead to be:

               (1) a dividend or distribution of the evidences of indebtedness,
          assets, shares of capital stock, rights or warrants other than such
          shares of Common Stock, such subdivision or combination or such rights
          or warrants to which Sections 12.4(a), 12.4(b) and 12.4(c) apply,
          respectively (and any Conversion Price reduction required by this
          Section 12.4(d) with respect to such dividend or distribution shall
          then be made), immediately followed by

               (2) a dividend or distribution of such shares of Common Stock,
          such subdivision or combination or such rights or warrants (and any
          further Conversion Price reduction required by Sections 12.4(a),
          12.4(b) and 12.4(c) with respect to such dividend or distribution
          shall then be made), except:

                    (A) the Record Date of such dividend or distribution shall
               be substituted as (x) "the date fixed for the determination of
               stockholders entitled to receive such dividend or other
               distribution", "Record Date fixed for such determinations" and
               "Record Date" within the meaning of Section 12.4(a), (y) "the day
               upon which such subdivision becomes effective" and "the day upon
               which such combination becomes effective" within the meaning of
               Section 12.4(b), and (z) as "the date fixed for the determination
               of stockholders entitled to receive such rights or warrants",
               "the Record Date fixed for the determination of the stockholders
               entitled to receive such rights or warrants" and such "Record
               Date" within the meaning of Section 12.4(c); and

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<PAGE>

                    (B) any shares of Common Stock included in such dividend or
               distribution shall not be deemed "outstanding at the close of
               business on the date fixed for such determination" within the
               meaning of Section 12.4(a) and any reduction or increase in the
               number of shares of Common Stock resulting from such subdivision
               or combination shall be disregarded in connection with such
               dividend or distribution.

          (e)  In case the Company shall, by dividend or otherwise, distribute
     to all holders of its Common Stock cash (excluding any cash that is
     distributed upon a reclassification, change, merger, consolidation,
     statutory share exchange, combination, sale or conveyance to which Section
     12.11 applies or as part of a distribution referred to in Section 12.4(d)),
     in an aggregate amount that, combined together with:

               (1)  the aggregate amount of any other such distributions to all
          holders of Common Stock made exclusively in cash within the 12 months
          preceding the date of payment of such distribution, and in respect of
          which no adjustment pursuant to this Section 12.4(e) has been made;
          and

               (2)  the aggregate of any cash plus the fair market value (as
          determined by the Board of Directors, whose determination shall be
          conclusive and set forth in a Board Resolution) of consideration
          payable in respect of any tender offer by the Company or any of its
          subsidiaries for all or any portion of the Common Stock concluded
          within the 12 months preceding the date of such distribution, and in
          respect of which no adjustment pursuant to Section 12.4(f) has been
          made;

     exceeds 10% of the product of the Current Market Price (determined as
     provided in Section 12.4(g)) on the Record Date with respect to such
     distribution times the number of shares of Common Stock outstanding on such
     date, then and in each such case, immediately after the close of business
     on such date, the Conversion Price shall be reduced so that the same shall
     equal the price determined by multiplying the Conversion Price in effect
     immediately prior to the close of business on such Record Date by a
     fraction:

               (i)  the numerator of which shall be equal to the Current Market
          Price on the Record Date less an amount equal to the quotient of (x)
          the excess of such combined amount over such 10% and (y) the number of
          shares of Common Stock outstanding on the Record Date, and

               (ii) the denominator of which shall be equal to the Current
          Market Price on such date.

     However, in the event that the then fair market value (as so determined) of
     the portion of the securities so distributed applicable to one share of
     Common Stock is equal to or greater than the Current Market Price on the
     Record Date, in lieu of the foregoing adjustment, adequate provision shall
     be made so that each Holder shall have the right to receive upon conversion
     of a Security (or any portion thereof) the amount of cash such Holder would
     have received had such Holder converted such Security (or portion thereof)

                                       72
<PAGE>

     immediately prior to such Record Date. In the event that such dividend or
     distribution is not so paid or made, the Conversion Price shall again be
     adjusted to be the Conversion Price which would then be in effect if such
     dividend or distribution had not been declared.

          (f)  In case a tender offer made by the Company or any of its
     subsidiaries for all or any portion of the Common Stock shall expire and
     such tender offer (as amended upon the expiration thereof) shall require
     the payment to stockholders (based on the acceptance (up to any maximum
     specified in the terms of the tender offer) of Purchased Shares (as defined
     below)) of an aggregate consideration having a fair market value (as
     determined by the Board of Directors, whose determination shall be
     conclusive and set forth in a Board Resolution) that combined together
     with:

               (1) the aggregate of the cash plus the fair market value (as
          determined by the Board of Directors, whose determination shall be
          conclusive and set forth in a Board Resolution), as of the expiration
          of such tender offer, of consideration payable in respect of any other
          tender offers, by the Company or any of its subsidiaries for all or
          any portion of the Common Stock expiring within the 12 months
          preceding the expiration of such tender offer and in respect of which
          no adjustment pursuant to this Section 12.4(f) has been made; and

               (2) the aggregate amount of any distributions to all holders of
          the Company's Common Stock made exclusively in cash within 12 months
          preceding the expiration of such tender offer and in respect of which
          no adjustment pursuant to Section 12.4(e) has been made, exceeds 10%
          of the product of the Current Market Price (determined as provided in
          Section 12.4(g)) as of the last time (the "Expiration Time") tenders
          could have been made pursuant to such tender offer (as it may be
          amended) times the number of shares of Common Stock outstanding
          (including any tendered shares) on the Expiration Time, then, and in
          each such case, immediately prior to the opening of business on the
          day after the date of the Expiration Time, 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 close
          of business on the date of the Expiration Time by a fraction:

                   (i)  the numerator of which shall be the number of shares of
               Common Stock outstanding (including any tendered shares) at the
               Expiration Time multiplied by the Current Market Price of the
               Common Stock on the Trading Day next succeeding the Expiration
               Time; and

                   (ii) the denominator shall be the sum of (x) the fair market
               value (determined as aforesaid) of the aggregate consideration
               payable to stockholders based on the acceptance (up to any
               maximum specified in the terms of the tender offer) of all shares
               validly tendered and not withdrawn as of the Expiration Time (the
               shares deemed so accepted, up to any such maximum, being referred
               to as the "Purchased Shares") and (y) the product of the number
               of shares of Common Stock outstanding (less any

                                       73
<PAGE>

               Purchased Shares) on the Expiration Time and the Current Market
               Price of the Common Stock on the Trading Day next succeeding the
               Expiration Time.

     Such reduction (if any) shall become effective immediately prior to the
     opening of business on the day following the Expiration Time.  In the event
     that the Company is obligated to purchase shares pursuant to any such
     tender offer, but the Company is permanently prevented by applicable law
     from effecting any such purchases or all such purchases are rescinded, the
     Conversion Price shall again be adjusted to be the Conversion Price which
     would then be in effect if such tender offer had not been made.  If the
     application of this Section 12.4(f) to any tender offer would result in an
     increase in the Conversion Price, no adjustment shall be made for such
     tender offer under this Section 12.4(f).

          (g) For purposes of this Section 12.4, the following terms shall have
     the meanings indicated:

              (1) "Current Market Price" shall mean the average of the daily
          Trading Prices per share of Common Stock for the ten consecutive
          Trading Days immediately prior to the date in question; provided,
          however, that if:

                  (i)   the "ex" date (as hereinafter defined) for any event
              (other than the issuance or distribution requiring such
              computation) that requires an adjustment to the Conversion Price
              pursuant to Section 12.4(a), (b), (c), (d), (e) or (f) occurs
              during such ten consecutive Trading Days, the Trading Price for
              each Trading Day prior to the "ex" date for such other event shall
              be adjusted by multiplying such Trading Price by the same fraction
              by which the Conversion Price is so required to be adjusted as a
              result of such other event;

                  (ii)  the "ex" date for any event (other than the issuance or
              distribution requiring such computation) that requires an
              adjustment to the Conversion Price pursuant to Section 12.4(a),
              (b), (c), (d), (e) or (f) occurs on or after the "ex" date for the
              issuance or distribution requiring such computation and prior to
              the day in question, the Trading Price for each Trading Day on and
              after the "ex" date for such other event shall be adjusted by
              multiplying such Trading Price by the reciprocal of the fraction
              by which the Conversion Price is so required to be adjusted as a
              result of such other event; and

                  (iii) the "ex" date for the issuance or distribution requiring
              such computation is prior to the day in question, after taking
              into account any adjustment required pursuant to clause (i) or
              (ii) of this proviso, the Trading Price for each Trading Day on or
              after such "ex" date shall be adjusted by adding thereto the
              amount of any cash and the fair market value (as determined by the
              Board of Directors in a manner consistent with any determination
              of such value for purposes of Section 12.4(d) or

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              (f), whose determination shall be conclusive and set forth in a
              Board Resolution) of the evidences of indebtedness, shares of
              capital stock or assets being distributed applicable to one share
              of Common Stock as of the close of business on the day before such
              "ex" date.

          For purposes of any computation under Section 12.4(f), the Current
          Market Price of the Common Stock on any date shall be deemed to be the
          average of the daily Trading Prices per share of Common Stock for such
          day and the next two succeeding Trading Days; provided, however, that
          if the "ex" date for any event (other than the tender offer requiring
          such computation) that requires an adjustment to the Conversion Price
          pursuant to Section 12.4(a), (b), (c), (d), (e) or (f) occurs on or
          after the Expiration Time for the tender or exchange offer requiring
          such computation and prior to the day in question, the Trading Price
          for each Trading Day on and after the "ex" date for such other event
          shall be adjusted by multiplying such Trading Price by the reciprocal
          of the fraction by which the Conversion Price is so required to be
          adjusted as a result of such other event.  For purposes of this
          paragraph, the term "ex" date, when used:

                  (A) with respect to any issuance or distribution, means the
              first date on which the Common Stock trades regular way on the
              relevant exchange or in the relevant market from which the Trading
              Price was obtained without the right to receive such issuance or
              distribution;

                  (B) with respect to any subdivision or combination of shares
              of Common Stock, means the first date on which the Common Stock
              trades regular way on such exchange or in such market after the
              time at which such subdivision or combination becomes effective;
              and

                  (C) with respect to any tender or exchange offer, means
              the first date on which the Common Stock trades regular way on
              such exchange or in such market after the Expiration Time of such
              offer.

          Notwithstanding the foregoing, whenever successive adjustments to the
          Conversion Price are called for pursuant to this Section 12.4, such
          adjustments shall be made to the Current Market Price as may be
          necessary or appropriate to effectuate the intent of this Section 12.4
          and to avoid unjust or inequitable results as determined in good faith
          by the Board of Directors.

              (2) "fair market value" shall mean the amount which a willing
          buyer would pay a willing seller in an arm's length transaction.

              (3) "Record Date" shall mean, with respect to any dividend,
          distribution or other transaction or event in which the holders of
          Common Stock have the right to receive any cash, securities or other
          property or in which the Common Stock (or other applicable security)
          is exchanged for or converted into any combination of cash, securities
          or other property, the date fixed for determination of stockholders
          entitled to receive such cash, securities or other

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          property (whether such date is fixed by the Board of Directors or by
          statute, contract or otherwise).

          (h) The Company may make such reductions in the Conversion Price, in
     addition to those required by Sections 12.4(a), (b), (c), (d), (e) or (f),
     as the Board of Directors considers to be advisable to avoid or diminish
     any income tax to holders of Common Stock or rights to purchase Common
     Stock resulting from any dividend or distribution of stock (or rights to
     acquire stock) or from any event treated as such for income tax purposes.

          To the extent permitted by applicable law, the Company from time to
     time may reduce the Conversion Price by any amount for any period of time
     if the period is at least 20 days and the reduction is irrevocable during
     the period and the Board of Directors determines in good faith that such
     reduction would be in the best interests of the Company, which
     determination shall be conclusive and set forth in a Board Resolution.
     Whenever the Conversion Price is reduced pursuant to the preceding
     sentence, the Company shall mail to the Trustee and each Holder at the
     address of such Holder as it appears in the Register a notice of the
     reduction at least 15 days prior to the date the reduced Conversion Price
     takes effect, and such notice shall state the reduced Conversion Price and
     the period during which it will be in effect.

          (i) No adjustment in the Conversion Price shall be required unless
     such adjustment would require an increase or decrease of at least 1% in
     such price; provided, however, that any adjustments which by reason of this
     Section 12.4(i) are not required to be made shall be carried forward and
     taken into account in any subsequent adjustment.  All calculations under
     this Article 12 shall be made by the Company and shall be made to the
     nearest cent or to the nearest one hundredth of a share, as the case may
     be.  No adjustment need be made for a change in the par value or no par
     value of the Common Stock.

          (j) In any case in which this Section 12.4 provides that an adjustment
     shall become effective immediately after a Record Date for an event, the
     Company may defer until the occurrence of such event (i) issuing to the
     Holder of any Security converted after such Record Date and before the
     occurrence of such event the additional shares of Common Stock issuable
     upon such conversion by reason of the adjustment required by such event
     over and above the Common Stock issuable upon such conversion before giving
     effect to such adjustment and (ii) paying to such holder any amount in cash
     in lieu of any fraction pursuant to Section 12.3.

          (k) For purposes of this Section 12.4, the number of shares of Common
     Stock at any time outstanding shall not include shares held in the treasury
     of the Company but shall include shares issuable in respect of scrip
     certificates issued in lieu of fractions of shares of Common Stock.  The
     Company will not pay any dividend or make any distribution on shares of
     Common Stock held in the treasury of the Company.

          (l) If the distribution date for the rights provided in the Company's
     rights agreement, if any, occurs prior to the date a Security is converted,
     the Holder of the

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     Security who converts such Security after the distribution date is not
     entitled to receive the rights that would otherwise be attached (but for
     the date of conversion) to the shares of Common Stock received upon such
     conversion; provided, however, that an adjustment shall be made to the
     Conversion Price pursuant to clause 12.4(b) as if the rights were being
     distributed to the common stockholders of the Company immediately prior to
     such conversion. If such an adjustment is made and the rights are later
     redeemed, invalidated or terminated, then a corresponding reversing
     adjustment shall be made to the Conversion Price, on an equitable basis, to
     take account of such event.

     Section 12.5 Notice of Adjustments of Conversion Price.

          Whenever the Conversion Price is adjusted as herein provided (other
than in the case of an adjustment pursuant to the second paragraph of Section
12.4(h) for which the notice required by such paragraph has been provided), the
Company shall promptly file with the Trustee and any Conversion Agent other than
the Trustee an Officers' Certificate setting forth the adjusted Conversion Price
and showing in reasonable detail the facts upon which such adjustment is based.
Promptly after delivery of such Officers' Certificate, the Company shall prepare
a notice stating that the Conversion Price has been adjusted and setting forth
the adjusted Conversion Price and the date on which each adjustment becomes
effective, and shall mail such notice to each Holder at the address of such
Holder as it appears in the Register within 20 days of the effective date of
such adjustment.  Failure to deliver such notice shall not affect the legality
or validity of any such adjustment.

     Section 12.6 Notice Prior to Certain Actions.

          In case at any time after the date hereof:

               (1) the Company shall declare a dividend (or any other
          distribution) on its Common Stock payable otherwise than in cash out
          of its capital surplus or its consolidated retained earnings;

               (2) the Company shall authorize the granting to the holders of
          its Common Stock of rights or warrants to subscribe for or purchase
          any shares of capital stock of any class (or of securities convertible
          into shares of capital stock of any class) or of any other rights;

               (3) there shall occur any reclassification of the Common Stock of
          the Company (other than a subdivision or combination of its
          outstanding Common Stock, a change in par value, a change from par
          value to no par value or a change from no par value to par value), or
          any merger, consolidation, statutory share exchange or combination to
          which the Company is a party and for which approval of any
          shareholders of the Company is required, or the sale, transfer or
          conveyance of all or substantially all of the assets of the Company;
          or

               (4) there shall occur the voluntary or involuntary dissolution,
          liquidation or winding up of the Company;

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<PAGE>

the Company shall cause to be filed at each office or agency maintained for the
purpose of conversion of securities pursuant to Section 9.2, and shall cause to
be provided to the Trustee and all Holders in accordance with Section 14.2, at
least 20 days (or 10 days in any case specified in clause (1) or (2) above)
prior to the applicable record or effective date hereinafter specified, a notice
stating:

          (A) the date on which a record is to be taken for the purpose of such
     dividend, distribution, rights or warrants, or, if a record is not to be
     taken, the date as of which the holders of Common Stock of record to be
     entitled to such dividend, distribution, rights or warrants are to be
     determined; or

          (B) the date on which such reclassification, merger, consolidation,
     statutory share exchange, combination, sale, transfer, conveyance,
     dissolution, liquidation or winding up is expected to become effective, and
     the date as of which it is expected that holders of Common Stock of record
     shall be entitled to exchange their shares of Common Stock for securities,
     cash or other property deliverable upon such reclassification, merger,
     consolidation, statutory share exchange, sale, transfer, dissolution,
     liquidation or winding up.

          Neither the failure to give such notice nor any defect therein shall
affect the legality or validity of the proceedings or actions described in
clauses (1) through (4) of this Section 12.6.

  Section 12.7 Company to Reserve Common Stock.

          The Company shall at all times use its best efforts to reserve and
keep available, free from preemptive rights, out of its authorized but unissued
Common Stock, for the purpose of effecting the conversion of Securities, the
full number of shares of fully paid and nonassessable Common Stock then issuable
upon the conversion of all Outstanding Securities.

  Section 12.8 Section Taxes on Conversions.

          Except as provided in the next sentence, the Company will pay any and
all taxes (other than taxes on income) and duties that may be payable in respect
of the issue or delivery of shares of Common Stock on conversion of Securities
pursuant hereto.  A Holder delivering a Security for conversion shall be liable
for and will be required to pay any tax or duty which may be payable in respect
of any transfer involved in the issue and delivery of shares of Common Stock in
a name other than that of the Holder of the Security or Securities to be
converted, and no such issue or delivery shall be made unless the Person
requesting such issue has paid to the Company the amount of any such tax or
duty, or has established to the satisfaction of the Company that such tax or
duty has been paid.

  Section 12.9 Covenant as to Common Stock.

          The Company covenants that all shares of Common Stock which may be
issued upon conversion of Securities will upon issue be fully paid and
nonassessable and, except as provided in Section 12.8, the Company will pay all
taxes, liens and charges with respect to the issue thereof.

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<PAGE>

  Section 12.10  Cancellation of Converted Securities.

          All Securities delivered for conversion shall be delivered to the
Trustee to be canceled by or at the direction of the Trustee, which shall
dispose of the same as provided in Section 2.15.

  Section 12.11  Effect of Reclassification, Consolidation, Merger or Sale.

          If any of following events occur, namely:

               (i)   any reclassification or change of the outstanding shares of
          Common Stock (other than a change in par value, or from par value to
          no par value, or from no par value to par value, or as a result of a
          subdivision or combination);

               (ii)  any merger, consolidation, statutory share exchange or
          combination of the Company with another corporation as a result of
          which holders of Common Stock shall be entitled to receive stock,
          securities or other property or assets (including cash) with respect
          to or in exchange for such Common Stock; or

               (iii) any sale or conveyance of the properties and assets of the
          Company as, or substantially as, an entirety to any other corporation
          as a result of which holders of Common Stock shall be entitled to
          receive stock, securities or other property or assets (including cash)
          with respect to or in exchange for such Common Stock;

the Company or the successor or purchasing corporation, as the case may be,
shall execute with the Trustee a supplemental indenture (which shall comply with
the TIA as in force at the date of execution of such supplemental indenture if
such supplemental indenture is then required to so comply) providing that such
Security shall be convertible into the kind and amount of shares of stock and
other securities or property or assets (including cash) which such Holder would
have been entitled to receive upon such reclassification, change, merger,
consolidation, statutory share exchange, combination, sale or conveyance had
such Securities been converted into Common Stock immediately prior to such
reclassification, change, merger, consolidation, statutory share exchange,
combination, sale or conveyance assuming such holder of Common Stock did not
exercise its rights of election, if any, as to the kind or amount of securities,
cash or other property receivable upon such merger, consolidation, statutory
share exchange, sale or conveyance (provided that, if the kind or amount of
securities, cash or other property receivable upon such merger, consolidation,
statutory share exchange, sale or conveyance is not the same for each share of
Common Stock in respect of which such rights of election shall not have been
exercised ("Non-Electing Share"), then for the purposes of this Section 12.11
the kind and amount of securities, cash or other property receivable upon such
merger, consolidation, statutory share exchange, sale or conveyance for each
Non-Electing Share shall be deemed to be the kind and amount so receivable per
share by a plurality of the Non-Electing Shares).   Such supplemental indenture
shall provide for adjustments which shall be as nearly equivalent as may be
practicable to the adjustments provided for in this Article 12.  If, in the case
of any such reclassification,

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<PAGE>

change, merger, consolidation, statutory share exchange, combination, sale or
conveyance, the stock or other securities and assets receivable thereupon by a
holder of shares of Common Stock includes shares of stock or other securities
and assets of a corporation other than the successor or purchasing corporation,
as the case may be, in such reclassification, change, merger, consolidation,
statutory share exchange, combination, sale or conveyance, then such
supplemental indenture shall also be executed by such other corporation and
shall contain such additional provisions to protect the interests of the Holders
of the Securities as the Board of Directors shall reasonably consider necessary
by reason of the foregoing, including to the extent practicable the provisions
providing for the Repurchase Rights set forth in Article 13.

          The Company shall cause notice of the execution of such supplemental
indenture to be mailed to each Holder, at the address of such Holder as it
appears on the Register, within 20 days after execution thereof.  Failure to
deliver such notice shall not affect the legality or validity of such
supplemental indenture.

          The above provisions of this Section shall similarly apply to
successive reclassifications, mergers, consolidations, statutory share
exchanges, combinations, sales and conveyances.

          If this Section 12.11 applies to any event or occurrence, Section 12.4
shall not apply.

  Section 12.12  Responsibility of Trustee for Conversion Provisions.

          The Trustee, subject to the provisions of Section 5.1, and any
Conversion Agent shall not at any time be under any duty or responsibility to
any Holder of Securities to determine whether any facts exist which may require
any adjustment of the Conversion Price, or with respect to the nature or intent
of any such adjustments when made, or with respect to the method employed, or
herein or in any supplemental indenture provided to be employed, in making the
same.  Neither the Trustee, subject to the provisions of Section 5.1, nor any
Conversion Agent shall be accountable with respect to the validity or value (of
the kind or amount) of any Common Stock, or of any other securities or property,
which may at any time be issued or delivered upon the conversion of any
Security; and it or they do not make any representation with respect thereto.
Neither the Trustee, subject to the provisions of Section 5.1, nor any
Conversion Agent shall be responsible for any failure of the Company to make any
cash payment or to issue, transfer or deliver any shares of stock or share
certificates or other securities or property upon the surrender of any Security
for the purpose of conversion; and the Trustee, subject to the provisions of
Section 5.1, and any Conversion Agent shall not be responsible or liable for any
failure of the Company to comply with any of the covenants of the Company
contained in this Article.

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                                  ARTICLE 13

                                 SUBORDINATION

  Section 13.1 Securities Subordinated to Senior Debt.

          The Company covenants and agrees, and each Holder of Securities, by
such Holder's acceptance thereof, likewise covenants and agrees, that the
Indebtedness represented by the Securities and the payment of the principal of
and premium, if any, and interest (including Additional Amounts, if any) on each
and all of the Securities is hereby expressly subordinated and junior, to the
extent and in the manner set forth and as set forth in this Section 13.1, in
right of payment to the prior payment in full of all Senior Debt.

          (a) In the event of any distribution of assets of the Company upon any
dissolution, winding up, liquidation or reorganization of the Company, whether
in bankruptcy, insolvency, reorganization or receivership proceedings or upon an
assignment for the benefit of creditors or any other marshalling of the assets
and liabilities of the Company or otherwise, the holders of all Senior Debt
shall first be entitled to receive payment of the full amount due thereon in
respect of all such Senior Debt and all other amounts due, or provision shall be
made for such amount in cash, or other payments satisfactory to the holders of
Senior Debt, before the Holders of any of the Securities are entitled to receive
any payment or distribution of any character, whether in cash, securities or
other property, on account of the principal of or premium, if any, or interest
(including Additional Amounts or Interest Make-Whole Payment, if any), if any on
the Indebtedness evidenced by the Securities.

          (b) In the event of any acceleration of Maturity of the Securities
because of an Event of Default, unless the full amount due in respect of all
Senior Debt is paid in cash or other form of payment satisfactory to the holders
of Senior Debt, no payment shall be made by the Company with respect to the
principal of, premium, if any, or interest (including Additional Amounts or
Interest Make-Whole Payment, if any) on the Securities or to acquire any of the
Securities (including any redemption, conversion or cash repurchase pursuant to
the exercise of the Repurchase Right), and the Company shall give prompt written
notice of such acceleration to such holders of Senior Debt.

          (c) In the event of and during the continuance of any default in
payment of the principal of or premium, if any, or interest on, rent or other
payment obligation in respect of, any Senior Debt, unless all such payments due
in respect of such Senior Debt have been paid in full in cash or other payments
satisfactory to the holders of Senior Debt, no payment shall be made by the
Company with respect to the principal of, premium, if any, or interest
(including Additional Amounts or Interest Make-Whole Payment, if any) on the
Securities or to acquire any of the Securities (including any redemption,
conversion or cash repurchase pursuant to the exercise of the Repurchase Right).
The Company shall give prompt written notice to the Trustee of any default under
any Senior Debt or under any agreement pursuant to which Senior Debt may have
been issued.

          (d) During the continuance of any event of default with respect to any
Designated Senior Debt, as such event of default is defined under any such
Designated Senior

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<PAGE>

Debt or in any agreement pursuant to which any Designated Senior Debt has been
issued (other than a default in payment of the principal of or premium, if any,
or interest on, rent or other payment obligation in respect of any Designated
Senior Debt), permitting the holder or holders of such Designated Senior Debt to
accelerate the maturity thereof (or in the case of any lease, permitting the
landlord either to terminate the lease or to require the Company to make an
irrevocable offer to terminate the lease following an event of default
thereunder), no payment shall be made by the Company, directly or indirectly,
with respect to principal of, premium, if any, or interest (including Additional
Amounts or Interest Make-Whole Payment, if any) on the Securities for 179 days
following notice in writing (a "Payment Blockage Notice") to the Company, from
any holder or holders of such Designated Senior Debt or their representative or
representatives or the trustee or trustees under any indenture or under which
any instrument evidencing any such Designated Senior Debt may have been issued,
that such an event of default has occurred and is continuing, unless such event
of default has been cured or waived or such Designated Senior Debt has been paid
in full; provided, however, if the maturity of such Designated Senior Debt is
accelerated (or in the case of any lease, as a result of such event of default,
the landlord under the lease has given the Company notice of its intention to
terminate the lease or to require the Company to make an irrevocable offer to
terminate the lease), no payment may be made on the Securities until such
Designated Senior Debt has been paid in full in cash or other payment
satisfactory to the holders of such Designated Senior Debt or such acceleration
(or termination, in the case of a lease) has been cured or waived.

          For purposes of this Section 13.1(d), such Payment Blockage Notice
shall be deemed to include notice of all other events of default under such
indenture or instrument which are continuing at the time of the event of default
specified in such Payment Blockage Notice.  The provisions of this Section
13.1(d) shall apply only to one such Payment Blockage Notice given in any period
of 365 days with respect to any issue of Designated Senior Debt, and no such
continuing event of default that existed or was continuing on the date of
delivery of any Payment Blockage Notice shall be, or shall be made, the basis
for a subsequent Payment Blockage Notice.

          (e) In the event that, notwithstanding the foregoing provisions of
Sections 13.1(a), 13.1(b), 13.1(c) and 13.1(d), any payment on account of
principal, premium, if any, or interest (including Additional Amounts or
Interest Make-Whole Payment, if any) on the Securities shall be made by or on
behalf of the Company and received by the Trustee, by any Holder or by any
Paying Agent (or, if the Company is acting as its own Paying Agent, money for
any such payment shall be segregated and held in trust):

          (i)   after the occurrence of an event specified in Section 13.1(a) or
     13.1(b), then, unless all Senior Debt is paid in full in cash, or provision
     shall be made therefor;

          (ii)  after the happening of an event of default of the type specified
     in Section 13.1(c) above, then, unless the amount of such Senior Debt then
     due shall have been paid in full, or provision made therefor or such event
     of default shall have been cured or waived; or

          (iii) after the happening of an event of default of the type
     specified in Section 13.1(d) above and delivery of a Payment Blockage
     Notice, then, unless such event of

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<PAGE>

     default shall have been cured or waived or the 179-day period specified in
     Section 13.1(d) shall have expired;

such payment (subject, in each case, to the provisions of Section 13.7) shall be
held in trust for the benefit of, and shall be immediately paid over to, the
holders of Designated Senior Debt (unless an event described in Section 13.1(a),
(b) or (c) has occurred, in which case the payment shall be held in trust for
the benefit of, and shall be immediately paid over to all holders of Senior
Debt) or their representative or representatives or the trustee or trustees
under any indenture under which any instruments evidencing any of the Designated
Senior Debt or Senior Debt, as the case may be, may have been issued, as their
interests may appear.

  Section 13.2 Subrogation.

          Subject to the payment in full of all Senior Debt to which the
Indebtedness evidenced by the Securities is in the circumstances subordinated as
provided in Section 13.1, the Holders of the Securities shall be subrogated to
the rights of the holders of such Senior Debt to receive payments or
distributions of cash, property or securities of the Company applicable to such
Senior Debt until all amounts owing on the Securities shall be paid in full,
and, as between the Company, its creditors other than holders of such Senior
Debt, and the Holders of the Securities, no such payment or distribution made to
the holders of Senior Debt by virtue of this Article which otherwise would have
been made to the holders of the Securities shall be deemed to be a payment by
the Company on account of such Senior Debt; provided, however,  that the
provisions of this Article are and are intended solely for the purpose of
defining the relative rights of the Holders of the Securities, on the one hand,
and the holders of Senior Debt, on the other hand.

  Section 13.3 Obligation of the Company is Absolute and Unconditional.

          Nothing contained in this Article or elsewhere in this Indenture or in
the Securities is intended to or shall impair, as between the Company, its
creditors other than the holders of Senior Debt, and the Holders of the
Securities, the obligation of the Company, which is absolute and unconditional,
to pay to the Holders of the Securities the principal of and premium, if any,
and interest (including Additional Amounts or Interest Make-Whole Payment, if
any) on the Securities as and when the same shall become due and payable in
accordance with their terms, or is intended to or shall affect the relative
rights of the Holders of the Securities and creditors of the Company other than
the holders of Senior Debt, nor shall anything contained herein or therein
prevent the Trustee or the Holder of any Security from exercising all remedies
otherwise permitted by applicable law upon default under this Indenture, subject
to the rights, if any, under this Article of the holders of Senior Debt in
respect of cash, property or securities of the Company received upon the
exercise of any such remedy.

  Section 13.4 Maturity of or Default on Senior Debt.

          Upon the maturity of any Senior Debt by lapse of time, acceleration or
otherwise, all principal of or premium, if any, or interest on, rent or other
payment obligations in respect of all such matured Senior Debt shall first be
paid in full, or such payment shall have been duly provided for, before any
payment on account of principal, or premium, if any, or interest

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(including Additional Amounts or Interest Make-Whole Payment, if any) is made
upon the Securities.

  Section 13.5 Payments on Securities Permitted.

          Except as expressly provided in this Article, nothing contained in
this Article shall affect the obligation of the Company to make, or prevent the
Company from making, payments of the principal of, or premium, if any, or
interest (including Additional Amounts or Interest Make-Whole Payment, if any)
on the Securities in accordance with the provisions hereof and thereof, or shall
prevent the Trustee or any Paying Agent from applying any monies deposited with
it hereunder to the payment of the principal of, or premium, if any, or interest
(including Additional Amounts or Interest Make-Whole Payment, if any) on the
Securities.

  Section 13.6 Effectuation of Subordination by Trustee.

          Each Holder of Securities, by such Holder's acceptance thereof,
authorizes and directs the Trustee on such Holder's behalf to take such action
as may be necessary or appropriate to effectuate the subordination provided in
this Article and appoints the Trustee such Holder's attorney-in-fact for any and
all such purposes.

          Upon any payment or distribution of assets of the Company referred to
in this Article, the Trustee and the Holders of the Securities shall be entitled
to rely upon any order or decree made by any court of competent jurisdiction in
which any such dissolution, winding up, liquidation or reorganization proceeding
affecting the affairs of the Company is pending or upon a certificate of the
trustee in bankruptcy, receiver, assignee for the benefit of creditors,
liquidating trustee or agent or other Person making any payment or distribution,
delivered to the Trustee or to the Holders of the Securities, for the purpose of
ascertaining the Persons entitled to participate in such payment or
distribution, and as to other facts pertinent to the right of such Persons under
this Article, and if such evidence is not furnished, the Trustee may defer any
payment to such Persons pending judicial determination as to the right of such
Persons to receive such payment.

  Section 13.7 Knowledge of Trustee.

          Notwithstanding the provision of this Article or any other provisions
of this Indenture, the Trustee shall not be charged with knowledge of the
existence of any Senior Debt, of any default in payment of principal of,
premium, if any, or interest on, rent or other payment obligation in respect of
any Senior Debt, or of any facts which would prohibit the making of any payment
of monies to or by the Trustee, or the taking of any other action by the
Trustee, unless a Responsible Officer of the Trustee having responsibility for
the administration of the trust established by this Indenture shall have
received written notice thereof from the Company, any Holder of Securities, any
Paying Agent or Conversion Agent of the Company or the holder or representative
of any class of Senior Debt, and, prior to the receipt of any such written
notice, the Trustee shall be entitled in all respects to assume that no such
default or facts exist; provided, however, that unless on the third Business Day
prior to the date upon which by the terms hereof any such monies may become
payable for any purpose the Trustee shall have received the notice provided for
in this Section 13.7, then, anything herein contained to the contrary

                                       84
<PAGE>

notwithstanding, the Trustee shall have full power and authority to receive such
monies and apply the same to the purpose for which they were received, and shall
not be affected by any notice to the contrary which may be received by it on or
after such date.

  Section 13.8 Trustee's Relation to Senior Debt.

          The Trustee shall be entitled to all the rights set forth in this
Article with respect to any Senior Debt at the time held by it, to the same
extent as any other holder of Senior Debt and nothing in this Indenture shall
deprive the Trustee of any of its rights as such holder.

          Nothing contained in this Article shall apply to claims of or payments
to the Trustee under or pursuant to Section 5.8.

          With respect to the holders of Senior Debt, the Trustee undertakes to
perform or to observe only such of its covenants and obligations as are
specifically set forth in this Article, and no implied covenants or obligations
with respect to the holders of Senior Debt shall be read into this Indenture
against the Trustee.  The Trustee shall not be deemed to owe any fiduciary duty
to the holders of Senior Debt and the Trustee shall not be liable to any holder
of Senior Debt if it shall pay over or deliver to Holders, the Company or any
other Person monies or assets to which any holder of Senior Debt shall be
entitled by virtue of this Article or otherwise.

  Section 13.9 Rights of Holders of Senior Debt Not Impaired.

          No right of any present or future holder of any Senior Debt to enforce
the subordination herein shall at any time or in any way be prejudiced or
impaired by any act or failure to act on the part of the Company or by any
noncompliance by the Company with the terms, provisions and covenants of this
Indenture, regardless of any knowledge thereof any such holder may have or be
otherwise charged with.

  Section 13.10  Modification of Terms of Senior Debt.

          Any renewal or extension of the time of payment of any Senior Debt or
the exercise by the holders of Senior Debt of any of their rights under any
instrument creating or evidencing Senior Debt, including without limitation the
waiver of default thereunder, may be made or done all without notice to or
assent from the Holders of the Securities or the Trustee.

          No compromise, alteration, amendment, modification, extension, renewal
or other change of, or waiver, consent or other action in respect of, any
liability or obligation under or in respect of, or of any of the terms,
covenants or conditions of any indenture or other instrument under which any
Senior Debt is outstanding or of such Senior Debt, whether or not such release
is in accordance with the provisions or any applicable document, shall in any
way alter or affect any of the provisions of this Article or of the Securities
relating to the subordination thereof.

  Section 13.11  Certain Conversions Not Deemed Payment.

          For the purposes of this Article 13 only:

                                       85
<PAGE>

               (1) the issuance and delivery of junior securities upon (A)
          conversion of Securities in accordance with Article 12 or (B)
          repurchase of Securities in accordance with Article 11 shall not be
          deemed to constitute a payment or distribution on account of the
          principal of, premium, if any, or interest (including Additional
          Amounts, if any) on Securities or on account of the purchase or other
          acquisition of Securities; and

               (2) the payment, issuance or delivery of cash (except in
          satisfaction of fractional shares pursuant to Section 12.3 or pursuant
          to Section 11.3), property or securities (other than junior
          securities) upon (A) conversion of a Security or (B) repurchase of
          Securities in accordance with Article 11 hereof shall be deemed to
          constitute payment on account of the principal of, premium, if any, or
          interest (including Additional Amounts, if any) on such Security.

For the purposes of this Section 13.11, the term "junior securities" means:

          (a) shares of any Common Stock of the Company; or

          (b) other securities of the Company that are subordinated in right of
          payment to all Senior Debt that may be outstanding at the time of
          issuance or delivery of such securities to substantially the same
          extent as, or to a greater extent that, the Securities are so
          subordinated as provided in this Article.

Nothing contained in this Article 13 or elsewhere in this Indenture or in the
Securities is intended to or shall impair, as among the Company, its creditors
(other than holders of Senior Debt) and the Holders of Securities, the right,
which is absolute and unconditional, of the Holder of any Security to convert
such Security in accordance with Article 12.

                                  ARTICLE 14

                    OTHER PROVISIONS OF GENERAL APPLICATION

  Section 14.1 Trust Indenture Act Controls.

          This Indenture is subject to the provisions of the TIA which are
required to be part of this Indenture, and shall, to the extent applicable, be
governed by such provisions.

  Section 14.2 Notices.

          Any notice or communication to the Company or the Trustee is duly
given if in writing and delivered in person or mailed by first-class mail to the
address set forth below:

     (a)  if to the Company:

          CuraGen Corporation

          555 Long Wharf Drive, 11/th/ Floor
          New Haven, CT 06511
          Attention: Elizabeth Whayland, Corporate Secretary

                                       86
<PAGE>

with a copy to:

          Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.
          One Financial Center
          Boston, MA 02111
          Attention: Michael Fantozzi, Esq.

     (b)  if to the Trustee:

          The Chase Manhattan Bank
          450 West 33/rd/ Street, 15th Floor
          New York, NY 10001
          Attention:  Capital Markets Fiduciary Services

The Company or the Trustee by notice to the other may designate additional or
different addresses for subsequent notices or communications.

          Any notice or communication to a Holder shall be mailed by first-class
mail to his address shown on the Register kept by the Registrar.  Failure to
mail a notice or communication to a Holder or any defect in such notice or
communication shall not affect its sufficiency with respect to other Holders.

          If a notice or communication is mailed or sent in the manner provided
above within the time prescribed, it is duly given as of the date it is mailed,
whether or not the addressee receives it, except that notice to the Trustee
shall only be effective upon receipt thereof by the Trustee.

          If the Company mails a notice or communication to Holders, it shall
mail a copy to the Trustee at the same time.

  Section 14.3 Communication by Holders with Other Holders.

          Holders may communicate pursuant to Section 312(b) of the TIA with
other Holders with respect to their rights under the Securities or this
Indenture.  The Company, the Trustee, the Registrar and anyone else shall have
the protection of Section 312(c) of the TIA.

  Section 14.4 Acts of Holders of Securities.

          (a) Any request, demand, authorization, direction, notice, consent,
waiver or other action provided by this Indenture to be given or taken by
Holders of Securities may be embodied in and evidenced by:

              (1) one or more instruments of substantially similar tenor signed
          by such Holders in person or by agent or proxy duly appointed in
          writing;

              (2) the record of Holders of Securities voting in favor thereof,
          either in person or by proxies duly appointed in writing, at any
          meeting of Holders of Securities duly called and held in accordance
          with the provisions of Article 8; or

                                       87
<PAGE>

              (3) a combination of such instruments and any such record.

Except as herein otherwise expressly provided, such action shall become
effective when such instrument or instruments or record or both are delivered to
the Trustee and, where it is hereby expressly required, to the Company.  Such
instrument or instruments and record (and the action embodied therein and
evidenced thereby) are herein sometimes referred to as the "Act" of the Holders
of Securities signing such instrument or instruments and so voting at such
meeting.  Proof of execution of any such instrument or of a writing appointing
any such agent or proxy, or of the holding by any Person of a Security, shall be
sufficient for any purpose of this Indenture and (subject to Section 5.1)
conclusive in favor of the Trustee and the Company if made in the manner
provided in this Section.  The record of any meeting of Holders of Securities
shall be proved in the manner provided in Section 8.6.

          (b) The fact and date of the execution by any Person of any such
instrument or writing may be provided in any manner which the Trustee reasonably
deems sufficient.

          (c) The principal amount and serial numbers of Securities held by any
Person, and the date of such Person holding the same, shall be proved by the
Register.

          (d) Any request, demand, authorization, direction, notice, consent,
election, waiver or other Act of the Holders of any Security shall bind every
future Holder of the same Security and the Holder of every Security issued upon
the registration of transfer thereof or in exchange therefor or in lieu thereof
in respect of anything done, omitted or suffered to be done by the Trustee or
the Company in reliance thereon, whether or not notation of such action is made
upon such Security.

  Section 14.5 Certificate and Opinion as to Conditions Precedent.

          In any case where several matters are required to be certified by, or
covered by an opinion of, any specified Person, it is not necessary that all
such matters be certified by, or covered by the opinion of, only one such
Person, or that they be so certified or covered by only one document, but one
such Person may certify or give an opinion with respect to some matters and one
or more other such Persons as to other matters, and any such Person may certify
or give an opinion as to such matters in one or several documents.

          Any certificate or opinion of an officer of the Company may be based,
insofar as it relates to legal matters, upon an Opinion of Counsel, unless such
officer knows, or in the exercise of reasonable care should know, that the
Opinion of Counsel with respect to the matters upon which such certificate or
opinion is based is erroneous.  Any such Opinion of Counsel may be based,
insofar as it relates to factual matters, upon a certificate or representations
by, an officer or officers of the Company stating that the information with
respect to such factual matters is in the possession of the Company, unless such
counsel knows, or in the exercise of reasonable care should know, that the
certificate or representations with respect to such matters are erroneous.

          Where any Person is required to make, give or execute two or more
applications, requests, consents, certificates, statements, opinions or other
instruments under this Indenture, they may, but need not, be consolidated and
form one instrument.

                                       88
<PAGE>

          Upon any application or request by the Company to the Trustee to take
any action under any provision of this Indenture, the Company shall furnish to
the Trustee an Officers' Certificate stating that all conditions precedent, if
any, provided for in this Indenture relating to the proposed action have been
complied with and an Opinion of Counsel stating that in the opinion of such
Counsel all such conditions precedent, if any, have been complied with, except
that in the case of any such application or request as to which the furnishing
of such documents is specifically required by any provision of this Indenture
relating to such particular application or request, no additional certificate or
opinion need be furnished.

  Section 14.6 Statements Required in Certificate or Opinion.

          Each certificate or opinion with respect to compliance with a
condition or covenant provided for in this Indenture shall include:

               (1) a statement that each individual signing such certificate or
          opinion on behalf of the Company has read such covenant or condition
          and the definitions herein relating thereto;

               (2) a brief statement as to the nature and scope of the
          examination or investigation upon which the statements or opinions
          contained in such certificate or opinion are based;

               (3) a statement that, in the opinion of each such individual, he
          has made such examination or investigation as is necessary to enable
          him to express an informed opinion as to whether or not such covenant
          or condition has been complied with; and

               (4) a statement as to whether, in the opinion of each such
          individual, such condition or covenant has been complied with.

  Section 14.7 Effect of Headings and Table of Contents.

          The Article and Section headings herein and the Table of Contents are
for convenience only and shall not affect the construction hereof.

  Section 14.8 Successors and Assigns.

          All covenants and agreements in this Indenture by the Company shall
bind its successors and assigns, whether so expressed or not.

  Section 14.9 Separability Clause.

          In case any provision in this Indenture or the Securities shall be
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.

                                       89
<PAGE>

  Section 14.10  Benefits of Indenture.

          Nothing contained in this Indenture or in the Securities, express or
implied, shall give to any Person, other than the parties hereto and their
successors hereunder, the holders of Senior Debt and the Holders of Securities,
any benefit or legal or equitable right, remedy or claim under this Indenture.

  Section 14.11  Section Governing Law.

          THIS INDENTURE AND THE SECURITIES SHALL BE GOVERNED BY, AND CONSTRUED
IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

  Section 14.12  Counterparts.

          This instrument may be executed in any number of counterparts, each of
which when so executed shall be deemed to be an original but all such
counterparts shall together constitute but one and the same instrument.

  Section 14.13  Legal Holidays.

          In any case where any Interest Payment Date, Redemption Date,
Repurchase Date or Stated Maturity of any Security or the last day on which a
Holder of a Security has a right to convert such Security shall not be a
Business Day at any Place of Payment or Place of Conversion, then
(notwithstanding any other provision of this Indenture or of the Securities)
payment of interest (including Additional Amounts, if any) or principal or
premium, if any, or conversion of the Securities, need not be made at such Place
of Payment or Place of Conversion on such day, but may be made on the next
succeeding Business Day at such Place of Payment or Place of Conversion with the
same force and effect as if made on the Interest Payment Date, Redemption Date,
Repurchase Date or at the Stated Maturity or on such last day for conversion;
provided, however, that in the case that payment is made on such succeeding
Business Day, no interest shall accrue on the amount so payable for the period
from and after such Interest Payment Date, Redemption Date, Repurchase Date or
Stated Maturity, as the case may be.

  Section 14.14  Recourse Against Others.

          No recourse for the payment of the principal of or premium, if any, or
interest (including Additional Amounts, if any) on any Security, or for any
claim based thereon or otherwise in respect thereof, shall be had against any
incorporator, shareholder, officer or director, as such, past, present or
future, of the Company or of any successor corporation, whether by virtue of any
constitution, statute or rule of law or by the enforcement of any assessment or
penalty or otherwise, all such liability being, by the acceptance thereof and as
part of the consideration for the issue thereof, expressly waived and released.

                                       90
<PAGE>

          IN WITNESS WHEREOF, the parties hereto have caused this Indenture to
be duly executed all as of the day and year first above written.
CURAGEN CORPORATION

                                    By: /s/ David M. Wurzer
                                        ------------------------
                                        Name: David M. Wurzer
                                        Title: EVP and CFO

                                    THE CHASE MANHATTAN BANK, as trustee
                                    and not in its individual capacity

                                    By: /s/ Victor Evans
                                        ------------------------
                                    Name: Victor Evans
                                    Title: Assistant Vice President

                                       91
<PAGE>

                                                                       EXHIBIT A
                               FORM OF SECURITY

                              [FACE OF SECURITY]

[THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE REFERRED
TO HEREIN.  THIS GLOBAL SECURITY MAY NOT BE EXCHANGED OR TRANSFERRED, IN WHOLE
BUT NOT IN PART, FOR A SECURITY REGISTERED IN THE NAME OF ANY PERSON OTHER THAN
DTC OR A NOMINEE THEREOF, EXCEPT IN THE LIMITED CIRCUMSTANCES SET FORTH IN THE
INDENTURE.  BENEFICIAL INTERESTS IN THIS GLOBAL SECURITY MAY NOT BE TRANSFERRED
EXCEPT IN ACCORDANCE WITH THE INDENTURE.]/1/
                                          -

[THE SECURITY EVIDENCED BY THIS CERTIFICATE HAS NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE
SECURITIES LAWS.  BY ACQUISITION HEREOF, THE HOLDER:

(1) REPRESENTS THAT (A) IT IS A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN
RULE 144A UNDER THE SECURITIES ACT, (B) IT IS A NON-U.S. PERSON WHO IS ACQUIRING
THIS SECURITY IN AN OFFSHORE TRANSACTION MEETING THE REQUIREMENTS OF RULE 903 OR
RULE 904 OF REGULATION S UNDER THE SECURITIES ACT; OR (C) IT IS AN INSTITUTIONAL
"ACCREDITED INVESTOR" AS DEFINED IN RULE 501(a)(1), (2), (3) OR (7) UNDER THE
SECURITIES ACT (AN "INSTITUTIONAL ACCREDITED INVESTOR") THAT IS PURCHASING AT
LEAST $100,000 IN AGGREGATE PRINCIPAL AMOUNT OF DEBENTURES OR AN "ACCREDITED
INVESTOR" AS DEFINED IN RULE 501(a)(4), (5) or (6) UNDER THE SECURITIES ACT (A
"NON-INSTITUTIONAL ACCREDITED INVESTOR") THAT IS PURCHASING AT LEAST $250,000 IN
AGGREGATE PRINCIPAL AMOUNT OF DEBENTURES;

(2) AGREES THAT NEITHER THE SECURITY EVIDENCED HEREBY NOR THE COMMON STOCK
ISSUABLE UPON CONVERSION OF SUCH SECURITY MAY BE RESOLD, PLEDGED OR OTHERWISE
TRANSFERRED (X) WITHIN TWO YEARS AFTER THE ORIGINAL ISSUANCE OF THE SECURITY
EVIDENCED HEREBY OR (Y) BY A HOLDER THAT WAS AN AFFILIATE OF THE COMPANY AT ANY
TIME DURING THE THREE MONTHS PRECEDING THE DATE OF SUCH RESALE, PLEDGE OR
TRANSFER, IN EITHER CASE, EXCEPT (A) TO THE COMPANY OR ANY SUBSIDIARY THEREOF,
(B) TO A QUALIFIED INSTITUTIONAL BUYER IN COMPLIANCE WITH RULE 144A UNDER THE
SECURITIES ACT, (C) TO A NON-U.S. PERSON OUTSIDE OF THE UNITED STATES IN
COMPLIANCE WITH REGULATIONS S UNDER THE SECURITIES ACT, (D) PURSUANT TO AN
EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT TO AN INSTITUTIONAL
ACCREDITED INVESTOR THAT IS PURCHASING DEBENTURES IN AGGREGATE PRINCIPAL AMOUNT
OF AT LEAST $100,000 OR TO A NON-INSTITUTIONAL ACCREDITED INVESTOR THAT IS
PURCHASING DEBENTURES IN AGGREGATE PRINCIPAL AMOUNT OF AT LEAST $250,000, AND
THAT, IN EITHER CASE, PRIOR TO SUCH TRANSFER, FURNISHES TO

                                      A-1
<PAGE>

THE CHASE MANHATTAN BANK, AS TRUSTEE (OR ANY SUCCESSOR TRUSTEE, AS APPLICABLE),
A SIGNED LETTER CONTAINING CERTAIN REPRESENTATIONS AND WARRANTIES RELATING TO
THE RESTRICTIONS ON TRANSFER OF THE SECURITY EVIDENCED HEREBY (THE FORM OF
LETTER CAN BE OBTAINED FROM SUCH TRUSTEE), (E) PURSUANT TO THE EXEMPTION FROM
REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT (IF AVAILABLE) OR (F)
PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE
SECURITIES ACT AND WHICH CONTINUES TO BE EFFECTIVE AT THE TIME OF SUCH TRANSFER;
AND

(3) AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THE SECURITY EVIDENCED
HEREBY IS TRANSFERRED (OTHER THAN A TRANSFER PURSUANT TO CLAUSE 2(F) ABOVE) A
NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND.

IN CONNECTION WITH ANY TRANSFER OF THE SECURITY EVIDENCED HEREBY WITHIN TWO
YEARS AFTER THE ORIGINAL ISSUANCE OF SUCH SECURITY (OTHER THAN A TRANSFER
PURSUANT TO CLAUSE (2)(F) ABOVE), THE HOLDER MUST CHECK THE APPROPRIATE BOX SET
FORTH ON THE REVERSE HEREOF RELATING TO THE MANNER OF SUCH TRANSFER AND SUBMIT
THIS CERTIFICATE TO THE TRUSTEE (OR ANY SUCCESSOR TRUSTEE, AS APPLICABLE).  IF
THE PROPOSED TRANSFER IS PURSUANT TO CLAUSE (2)(B), 2(C), 2(D) OR 2(E) ABOVE,
THE HOLDER MUST, PRIOR TO SUCH TRANSFER, FURNISH TO THE TRUSTEE (OR ANY
SUCCESSOR TRUSTEE, AS APPLICABLE), SUCH 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.  THIS LEGEND WILL BE
REMOVED UPON THE EARLIER OF THE TRANSFER OF THE SECURITY EVIDENCED HEREBY
PURSUANT TO CLAUSE (2)(F) ABOVE OR THE EXPIRATION OF TWO YEARS FROM THE ORIGINAL
ISSUANCE OF THE SECURITY EVIDENCED HEREBY.  AS USED HEREIN, THE TERMS "UNITED
STATES" AND "U.S. PERSON" HAVE THE MEANINGS GIVEN TO THEM BY REGULATION S UNDER
THE SECURITIES ACT.]/2/
                     -

[THIS SECURITY WILL NOT BE ACCEPTED IN EXCHANGE FOR A BENEFICIAL INTEREST IN A
GLOBAL SECURITY UNLESS THE HOLDER OF THIS SECURITY, SUBSEQUENT TO SUCH EXCHANGE,
WILL HOLD EITHER NO DEBENTURES OR A MINIMUM AGGREGATE BENEFICIAL INTEREST IN THE
DEBENTURES OF AT LEAST (I) TWO HUNDRED FIFTY THOUSAND DOLLARS ($250,000), IF
SUCH HOLDER IS A NON-INSTITUTIONAL INSTITUTIONAL ACCREDITED INVESTOR, OR (II)
ONE HUNDRED THOUSAND DOLLARS ($100,000), IF SUCH HOLDER IS AN INSTITUTIONAL
ACCREDITED INVESTOR.]/3/
                      -

                                      A-2
<PAGE>

                              CURAGEN CORPORATION

               6.00% Convertible Subordinated Debenture due 2007
                              (the "Debentures")

                                     No. 1
<TABLE>
<S>                                              <C>
Original principal balance of all Debentures     Initial principal balance of this Debenture:
(including this Debenture): $                    $
</TABLE>

CUSIP: [23126RAB71]/1/
       [23126RAA9]/3/

          CURAGEN CORPORATION, a Delaware corporation (the "Company", which term
includes any successor corporation under the Indenture hereinafter referred to),
for value received, hereby promises to pay to __________________ or its
registered assigns, the principal sum of  ___________________________________
U.S. Dollars ($____________________________) on February 2, 2007.

          Interest Payment Dates: August 2 and February 2, commencing August 2,
2000

          Regular Record Dates: July 19 and January 19

          Reference is hereby made to the further provisions of this Security
set forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

                                      A-3
<PAGE>

          IN WITNESS WHEREOF, the Company has caused this Security to be duly
executed manually or by facsimile by its duly authorized officers.

Dated: February 2, 2000            CURAGEN CORPORATION


                                   By:_____________________________________
                                   Name:
                                   Title:


                                   By:_____________________________________
                                   Name:
                                   Title:


Trustee's Certificate of Authentication

This is one of the 6.00% Convertible Subordinated
Debentures due 2007 described in the within-named
Indenture.

THE CHASE MANHATTAN BANK,
as Trustee

By:_______________________________________
           Authorized Signatory

Dated:  February 2, 2000

                                      A-4
<PAGE>

                             [REVERSE OF SECURITY]
                              CURAGEN CORPORATION

               6.00% Convertible Subordinated Debenture due 2007

          Capitalized terms used herein but not defined shall have the meanings
assigned to them in the Indenture referred to below unless otherwise indicated.

1.   Principal and Interest.

          CuraGen Corporation, a Delaware corporation (the "Company"), promises
to pay interest on the principal amount of this Security at the Interest Rate
from February 2, 2000 until repayment at Maturity, redemption or repurchase.
The Company will pay interest on this Security semiannually in arrears on August
2 and February 2 of each year (each an "Interest Payment Date"), commencing
August 2, 2000.

          Interest on the Securities shall be computed (i) for any full
semiannual period for which a particular Interest Rate is applicable on the
basis of a 360-day year of twelve 30-day months and (ii) for any period for
which a particular Interest Rate is applicable shorter than a full semiannual
period for which interest is calculated, on the basis of a 30-day month and, for
such periods of less than a month, the actual number of days elapsed over a 30-
day month.

          A Holder of any Security at the close of business on a Regular Record
Date shall be entitled to receive interest on such Security on the corresponding
Interest Payment Date.  A Holder of any Security which is converted after the
close of business on a Regular Record Date and prior to the corresponding
Interest Payment Date (other than any Security whose Maturity is prior to such
Interest Payment Date) shall be entitled to receive interest on the principal
amount of such Security, notwithstanding the conversion of such Security prior
to such Interest Payment Date.  However, any such Holder which surrenders any
such Security for conversion during the period between the close of business on
such Regular Record Date and ending with the opening of business on the
corresponding Interest Payment Date shall be required to pay the Company an
amount equal to the interest on the principal amount of such Security so
converted, which is payable by the Company to such Holder on such Interest
Payment Date, at the time such Holder surrenders such Security for conversion.
Notwithstanding the foregoing, any such Holder which surrenders for conversion
any Security which has been called for redemption by the Company in a notice of
redemption given by the Company pursuant to Section 10.5 of the Indenture shall
be entitled to receive (and retain) such interest and need not pay the Company
an amount equal to the interest on the principal amount of such Security so
converted at the time such Holder surrenders such Security for conversion.

          In accordance with the terms of the Resale Registration Rights
Agreement, dated February 2, 2000 (the "Registration Rights Agreement"), between
the Company and Lehman Brothers Inc., Morgan Stanley & Co. Incorporated and Dain
Rauscher Incorporated, during the first 90 days following a Registration Default
(as defined in the Registration Rights Agreement), the Interest Rate borne by
the Securities shall be increased by 0.25% on:

                                      A-5
<PAGE>

          (A) May 2, 2000, if the Shelf Registration Statement (as defined in
     the Registration Rights Agreement) is not filed prior to or on May 2, 2000;

          (B) July 31, 2000, if the Shelf Registration Statement is not declared
     effective by the Securities and Exchange Commission prior to or on July 31,
     2000;

          (C) the day after the fifth Business Day after the Shelf Registration
     Statement, previously declared effective, ceases to be effective or fails
     to be usable, if a post-effective amendment (or report filed pursuant to
     the Exchange Act) that cures the Shelf Registration Statement is not filed
     with the Securities and Exchange Commission during such five Business Day
     period; or

          (D) the day following the 45/th/ or 60/th/ day, as the case may be, of
     any period that the prospectus contained in the Shelf Registration
     Statement has been suspended, if such suspension has not been terminated.

From and after the 91/st/ day following such Registration Default, the Interest
Rate borne by the Securities shall be increased by 0.50%.  In no event shall the
Interest Rate borne by the Securities be increased by more than 0.50%.

          Any amount of additional interest will be payable in cash
semiannually, in arrears, on each Interest Payment Date and will cease to accrue
on the date the Registration Default is cured.  The Holder of this Security is
entitled to the benefits of the Registration Rights Agreement.

2.   Method of Payment.

          Interest on any Security which is payable, and is punctually paid or
duly provided for, on any Interest Payment Date shall be paid to the person in
whose name that Security (or one or more Predecessor Securities) is registered
at the close of business on the Regular Record Date for such interest.

          Principal of, and premium, if any, and interest (including Additional
Amounts or Interest Make-Whole Payment, if any) on, Global Securities will be
payable to the Depositary in immediately available funds.

          Principal and premium, if any, on Physical Securities will be payable
at the office or agency of the Company maintained for such purpose, initially
the Corporate Trust Office of the Trustee.  Interest (including Additional
Amounts or Interest Make-Whole Payment, if any) on Physical Securities will be
payable by (i) U.S. Dollar check drawn on a bank in The City of New York mailed
to the address of the Person entitled thereto as such address shall appear in
the Register, or (ii) upon application to the Registrar not later than the
relevant Record Date by a Holder of an aggregate principal amount in excess of
$5,000,000, wire transfer in immediately available funds.

                                      A-6
<PAGE>

3.   Paying Agent and Registrar.

          Initially, The Chase Manhattan Bank, the Trustee under the Indenture,
will act as Paying Agent and Registrar.  The Company may change the Paying Agent
or Registrar without notice to any Holder.

4.   Indenture.

          The Company issued this Security under an Indenture, dated as of
February 2, 2000 (the "Indenture"), between the Company and The Chase Manhattan
Bank, as trustee (the "Trustee").  The terms of the Security include those
stated in the Indenture and those made part of the Indenture by reference to the
Trust Indenture Act of 1939, as amended ("TIA").  This Security is subject to
all such terms, and Holders are referred to the Indenture and the TIA for a
statement of all such terms.  To the extent permitted by applicable law, in the
event of any inconsistency between the terms of this Security and the terms of
the Indenture, the terms of the Indenture shall control.

5.   Optional Redemption.

          Provisional Redemption.
          ----------------------

          This Security may be redeemed in whole or in part, upon not less than
20 nor more than 60 days' notice, at any time prior to February 2, 2003, at the
option of the Company, at a Redemption Price equal to 103.0000% (expressed as a
percentage of the principal amount), plus interest accrued but unpaid to the
Redemption Date, if the following conditions are satisfied:

          (a) the Shelf Registration Statement is effective and available for
use and is expected to remain effective and available for use for the 30 days
following the Redemption Date; and

          (b) the Current Market Value of the Company's Common Stock equals or
exceeds, for at least 20 Trading Days in any period of 30 consecutive Trading
Days (ending on the Trading Day prior to the date the notice of redemption is
mailed) the following Trigger Percentages:

          During the Twelve                        Trigger
          Months Commencing                        Percentage
          -----------------                        ----------

          February 2, 2000                         170%

          February 2, 2001                         160%

          February 2, 2002                         150%


          Upon any provisional redemption, the Company shall also pay an
Interest Make-Whole Payment in cash or in shares of Common Stock, as described
in and subject to the conditions set forth in the Indenture.

                                      A-7
<PAGE>

          Non-provisional Redemption.  This Security may be redeemed in whole or
          --------------------------
in part, upon not less than 20 nor more than 60 days' notice, at any time on or
after February 2, 2003, at the option of the Company, at the Redemption Prices
(expressed as percentages of the principal amount) set forth below, plus any
interest accrued but unpaid to the Redemption Date.


          During the Twelve
          Months Commencing                          Redemption Prices
          -----------------                          -----------------
          February 2, 2003                           103.0000%
          February 2, 2004                           102.0000%
          February 2, 2005                           101.0000%
          February 2, 2006                           100.0000%

          General.   Securities in original denominations larger than $1,000 may
          -------
be redeemed in part.  If any Security selected for partial redemption is
converted in part before termination of the conversion right with respect to the
portion of the Security so selected, the converted portion of such Security
shall be deemed to be the portion selected for redemption (provided, however,
that the Holder of such Security so converted and deemed redeemed shall not be
entitled to any additional interest payment as a result of such deemed
redemption than such Holder would have otherwise been entitled to receive upon
conversion of such Security).  Securities which have been converted during a
selection of Securities to be redeemed may be treated by the Trustee as
Outstanding for the purpose of such selection.

          On and after the Redemption Date, interest ceases to accrue on
Securities or portions of Securities called for redemption, unless the Company
defaults in the payment of the Redemption Price.

          Notice of redemption will be given by the Company to the Holders as
provided in the Indenture.

6.   Repurchase Right Upon a Change of Control.

          If a Change in Control occurs, the Holder of Securities, at the
Holder's option, shall have the right, in accordance with the provisions of the
Indenture, to require the Company to repurchase the Securities (or any portion
of the principal amount hereof that is at least an integral multiple of $1,000,
provided that the portion of the principal amount of this Security to be
Outstanding after such repurchase is at least equal to $1,000) at the Repurchase
Price in cash, plus any interest accrued and unpaid to the Repurchase Date.

          Subject to the conditions provided in the Indenture, the Company may
elect to pay the Repurchase Price by delivering a number of shares of Common
Stock equal to (i) a Repurchase Price divided by (ii) 95% of the average of the
Trading Prices per share for the five consecutive Trading Days immediately
preceding and including the third Trading Day prior to the Repurchase Date.

                                      A-8
<PAGE>

          No fractional shares of Common Stock will be issued upon repurchase of
any Securities.  Instead of any fractional share of Common Stock which would
otherwise be issued upon conversion of such Securities, the Company shall pay a
cash adjustment as provided in the Indenture.

          A Company Notice will be given by the Company to the Holders as
provided in the Indenture.  To exercise a repurchase Right, a Holder must
deliver to the Trustee a written notice as provided in the Indenture.

7.   Conversion Rights.

          Subject to and upon compliance with the provisions of the Indenture,
the Holder of Securities is entitled, at such Holder's option, at any time
before the close of business on the Business Day immediately preceding February
2, 2007, to convert the Holder's Securities (or any portion of the principal
amount hereof which is an integral multiple of $1,000), at the principal amount
thereof or of such portion, into duly authorized, fully paid and nonassessable
shares of Common Stock of the Company at the Conversion Price in effect at the
time of conversion.

          In the case of a Security (or a portion thereof) called for
redemption, such conversion right in respect of the Security (or such portion
thereof) so called, shall expire at the close of business on the second Business
Day preceding the Redemption Date, unless the Company defaults in making the
payment due upon redemption.  In the case of a Change of Control for which the
Holder exercises its Repurchase Right with respect to a Security (or a portion
thereof), such conversion right in respect of the Security (or portion thereof)
shall expire at the close of business on the Business Day preceding the
Repurchase Date.

          The Conversion Price shall be initially equal to $127.6550 per share
of Common Stock.  The Conversion Price shall be adjusted under certain
circumstances as provided in the Indenture.

          To exercise the conversion right, the Holder must surrender the
Security (or portion thereof) duly endorsed or assigned to the Company or in
blank, at the office of the Conversion Agent, accompanied by a duly signed
conversion notice to the Company.  Any Security surrendered for conversion
during the period from the close of business on any Regular Record Date to the
opening of business on the corresponding Interest Payment Date (other than any
Security whose Maturity is prior to such Interest Payment Date), shall also be
accompanied by payment in New York Clearing House funds or other funds
acceptable to the Company of an amount equal to the interest payable on such
Interest Payment Date on the principal amount of the Securities being
surrendered for conversion.

          No fractional shares of Common Stock will be issued upon conversion of
any Securities.  Instead of any fractional share of Common Stock which would
otherwise be issued upon conversion of such Securities, the Company shall pay a
cash adjustment as provided in the Indenture.

                                      A-9
<PAGE>

8.   Subordination.

          The Indebtedness evidenced by this Security is, to the extent and in
the manner provided in the Indenture, subordinated and subject in right of
payment to the prior payment in full of all amounts then due on all Senior Debt
of the Company, and this Security is issued subject to such provisions of the
Indenture with respect thereto.  Each Holder of this Security, by accepting the
same, (a) agrees to and shall be bound by such provisions, (b) authorizes and
directs the Trustee on such Holder's behalf to take such action as may be
necessary or appropriate to effectuate the subordination so provided and (c)
appoints the Trustee such Holder's attorney-in-fact for any and all such
purposes.

9.   Denominations; Transfer; Exchange.

          The Securities are issuable in registered form, without coupons, in
denominations of $1,000 and integral multiples of $1,000 in excess thereof.  A
Holder may register the transfer or exchange of Securities in accordance with
the Indenture.  The Registrar may require a Holder, among other things, to
furnish appropriate endorsements and transfer documents and the Company may
require a Holder to pay any taxes and fees required by law or permitted by the
Indenture.

          In the event of a redemption in part, the Company will not be required
(a) to register the transfer of, or exchange, Securities for a period of 15 days
immediately preceding the date notice is given identifying the serial numbers of
the Securities called for such redemption, or (b) to register the transfer of,
or exchange, any such Securities, or portion thereof, called for redemption.

          In the event of redemption, conversion or repurchase of the Securities
in part only, a new Security or Securities for the unredeemed, unconverted or
unrepurchased portion thereof will be issued in the name of the Holder hereof.

10.  Persons Deemed Owners.

          The registered Holder of this Security shall be treated as its owner
for all purposes.

11.  Unclaimed Money.

          The Trustee and the Paying Agent shall pay to the Company any money
held by them for the payment of principal, premium, if any, or interest that
remains unclaimed for two years after the date upon which such payment shall
have become due.  After payment to the Company, Holders entitled to the money
must look to the Company for payment as general creditors unless an applicable
abandoned property law designates another Person, and all liability of the
Trustee and such Paying Agent with respect to such money shall cease.

12.  Discharge Prior to Redemption or Maturity.

          Subject to certain conditions contained in the Indenture, the Company
may discharge its obligations under the Securities and the Indenture if (1) (a)
all of the Outstanding

                                     A-10
<PAGE>

Securities shall become due and payable at their scheduled Maturity within one
year or (b) all of the Outstanding Securities are scheduled for redemption
within one year, and (2) the Company shall have deposited with the Trustee money
and/or U.S. Government Obligations sufficient to pay the principal of, and
premium, if any, and interest on, all of the Outstanding Securities on the date
of Maturity or redemption, as the case may be.

13.  Amendment; Supplement; Waiver.

          The Indenture permits, with certain exceptions as therein provided,
the amendment thereof and the modification of the rights and obligations of the
Company and the rights of the Holders of the Securities under the Indenture at
any time by the Company and the Trustee with the consent of the Holders of a
majority in aggregate principal amount of the Outstanding Securities (or such
lesser amount as shall have acted at a meeting pursuant to the provisions of the
Indenture).  The Indenture also contains provisions permitting the Holders of
specified percentages in principal amount of the Securities at the time
Outstanding, on behalf of the Holders of all the Securities, to waive compliance
by the Company with certain provisions of the Indenture and certain past
defaults under the Indenture and their consequences.  Any such consent or waiver
by the Holder of this Security shall be conclusive and binding upon such Holder
and upon all future Holders of this Security and of any Security issued upon
registration of transfer hereof or in exchange herefor or in lieu hereof,
whether or not notation of such consent or waiver is made upon this Security or
such other Security.

          No reference herein to the Indenture and no provision of this Security
or of the Indenture shall alter or impair the obligation of the Company, which
is absolute and unconditional, to pay the principal of and premium, if any, and
interest (including Additional Amounts or Interest Make-Whole Payment, if any)
on this Security at the times, places and rate, and in the coin or currency,
herein prescribed or to convert this Security (or pay cash in lieu of
conversion) as provided in the Indenture.

14.  Defaults and Remedies.

          The Indenture provides that an Event of Default with respect to the
Securities occurs when any of the following occurs:

          (a) the Company defaults in the payment of the principal of or
     premium, if any, on any of the Securities when it becomes due and payable
     at Maturity, upon redemption or exercise of a Repurchase Right or
     otherwise, whether or not such payment is prohibited by the subordination
     provisions of Article 13 of the Indenture;

          (b) the Company defaults in the payment of interest (including
     Additional Amounts or Interest Make-Whole Payment, if any) on any of the
     Securities when it becomes due and payable and such default continues for a
     period of 30 days, whether or not such payment is prohibited by the
     subordination provisions of Article 13 of the Indenture;

          (c) the Company fails to perform or observe any other term, covenant
     or agreement contained in the Securities or the Indenture and such default
     continues for a

                                     A-11
<PAGE>

     period of 60 days after written notice of such failure is given as
     specified in the Indenture;

          (d) (i) the Company fails to make any payment by the end of the
     applicable grace period, if any, any payment of principal or interest due
     in respect of any Indebtedness for borrowed money, the aggregate
     outstanding principal amount of which is an amount in excess of $7,500,000;
     or (ii) there is an acceleration of any Indebtedness for borrowed money in
     an amount in excess of $7,500,000 because of a default with respect to such
     Indebtedness without such Indebtedness having been discharged or such
     acceleration having been cured, waived, rescinded or annulled, in the case
     of either (i) or (ii) above, for a period of 30 days after written notice
     of such failure is given as specified in the Indenture; or

          (e) there are certain events of bankruptcy, insolvency or
     reorganization of the Company.

          If an Event of Default shall occur and be continuing, the principal of
all the Securities may be declared due and payable in the manner and with the
effect provided in the Indenture.

15.  Authentication.

          This Security shall not be valid until the Trustee (or authenticating
agent) executes the certificate of authentication on the other side of this
Security.

16.  Abbreviations.

          Customary abbreviations may be used in the name of a Holder or an
assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the
entireties), JT TEN (= joint tenants with right of survivorship and not as
tenants in common), CUST (= Custodian) and U/G/M/A (= Uniform Gifts to Minors
Act).

17.  Additional Rights of Holders of Transfer Restricted Securities.

          In addition to the rights provided to Holders under the Indenture,
Holders of Transfer Restricted Securities shall have all the rights set forth in
the Registration Rights Agreement.

18.  CUSIP Numbers.

          Pursuant to a recommendation promulgated by the Committee on Uniform
Security Identification Procedures, the Company has caused CUSIP numbers to be
printed on this Security and the Trustee may use CUSIP numbers in notices of
redemption as a convenience to Holders.  No representation is made as to the
accuracy of such numbers either as printed on this Security or as contained in
any notice of redemption and reliance may be placed only on the other
identification numbers placed thereon.

19.  Governing Law.

                                     A-12
<PAGE>

          The Indenture and this Security shall be governed by, and construed in
accordance with, the law of the State of New York.

20.  Successor Corporation.

          In the event a successor corporation assumes all the obligations of
the Company under this Security, pursuant to the terms hereof  and of the
Indenture, the Company will be released from all such obligations.

                                     A-13
<PAGE>

                                ASSIGNMENT FORM

    To assign this Security, fill in the form below and have your signature
         guaranteed: (I) or (we) assign and transfer this Security to:

________________________________________________________________________________
                 (Insert assignee's soc. sec. or tax I.D. no.)

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________
             (Print or type assignee's name, address and zip code)

and irrevocably appoint ________________________________________________________
to transfer this Security on the books of the Company.  The agent may substitute
another to act for him.

Dated:________________   Your Name: ____________________________________________
                         (Print your name exactly as it appears on the face of
                         this Security)

                         Your Signature:________________________________________
                         (Sign exactly as your name appears on the face of this
                         Security)

                         Signature Guarantee*:__________________________________



     * Participant in a recognized Signature Guarantee Medallion Program (or
other signature guarantor acceptable to the Trustee).

                                     A-14
<PAGE>

In connection with any transfer of this Security occurring prior to the date
which is the earlier of the end of the period referred to in Rule 144(k) under
the Securities Act of 1933, as amended (the "Securities Act"), the undersigned
confirms that without utilizing any general solicitation or general advertising
that:

               [Check One]

[  ] (a)  this Security is being transferred in compliance with the exemption
          from registration under the Securities Act provided by Rule 144A
          thereunder, and that the transfer has been effected pursuant to and in
          accordance with Rule 144A under the Securities Act and, accordingly,
          the undersigned does hereby further certify that the Securities are
          being transferred to a transferee that the undersigned reasonably
          believes is purchasing the Securities for its own account, or for one
          or more accounts with respect to which such transferee exercises sole
          investment discretion, and such transferee and each such account is a
          "qualified institutional buyer" within the meaning of Rule 144A, in
          each case in a transaction meeting the requirements of Rule 144A and
          in accordance with any applicable securities laws of any state of the
          United States.

               or

[  ] (b)  this Security is being transferred in compliance with the exemption
          from registration under the Securities Act provided by Regulation S
          thereunder, and (A) the offer of the Securities was not made to a
          person in the United States; (B) either: (i) at the time the buy order
          was originated, the transferee was outside the United States or the
          Transferor and any person acting on its behalf reasonably believed
          that the transferee was outside the United States, or (ii) the
          transaction was executed in, on or through the facilities of a
          designated offshore securities market and neither the Transferor nor
          any person acting on its behalf knows that the transaction was pre-
          arranged with a buyer in the United States; (C) no directed selling
          efforts have been made in contravention of the requirements of Rule
          903(b) or 904(b) of Regulation S, as applicable; and (D) the
          transaction is not part of a plan or scheme to evade the registration
          requirements of the Securities Act.

               or

[  ] (c)  this Security is being transferred other than in accordance with (a)
          or (b) above and documents are being furnished which comply with the
          conditions of transfer set forth in this Security and the Indenture.

                                     A-15
<PAGE>

If none of the foregoing boxes is checked, the Trustee or other Registrar shall
not be obligated to register this Security in the name of any Person other than
the Holder hereof unless the conditions to any such transfer of registration set
forth herein and in Sections 2.7, 2.8 and 2.9 of the Indenture shall have been
satisfied.

Dated:__________       _______________________________________________________
                       NOTICE: The signature to this assignment must
                       correspond with the name as written upon the face of
                       the within-mentioned instrument in every particular,
                       without alteration or any change whatsoever.

                       Signature Guarantee:


                       _______________________________________________________

                       Signature must be guaranteed by a participant in a
                       recognized signature guaranty medallion program or
                       other signature guarantor acceptable to the Trustee.

                                     A-16
<PAGE>

TO BE COMPLETED BY PURCHASER IF (a) ABOVE IS CHECKED.

          The undersigned represents and warrants that: (a) it is purchasing
this Security for its own account or an account with respect to which it
exercises sole investment discretion, in each case for investment and not with a
view to distribution; (b) it and any such account is a "Qualified Institutional
Buyer" within the meaning of Rule 144A under the Securities Act of 1933; (c) it
is aware that the sale to it is being made in reliance on Rule 144A; (d) it
acknowledges that it has received such information regarding the Company as the
undersigned has requested pursuant to Rule 144A or has determined not to request
such information; and (e) it is aware that the transferor is relying upon the
undersigned's foregoing representations in order to claim the exemption from
registration provided by Rule 144A.



Dated:_______________         ________________________________________________
                              NOTICE: To be executed by an executive officer


TO BE COMPLETED BY PURCHASER IF (b) ABOVE IS CHECKED.

          The undersigned represents and warrants that it is purchasing the
Securities for its own account or an account with respect to which it exercises
sole investment discretion and that it and any such account are not "U.S.
persons" as defined in Regulation S under the Securities Act.



Dated:_______________          _______________________________________________
                               NOTICE:  To be executed by an executive officer

                                     A-17
<PAGE>

                               CONVERSION NOTICE

TO:  CURAGEN CORPORATION
     555 Long Wharf Drive
     New Haven, Connecticut 06511

          The undersigned registered owner of this Security hereby irrevocably
exercises the option to convert this Security, or the portion hereof (the
principal amount of which is an integral multiple of $1,000) below designated,
into shares of Common Stock in accordance with the terms of the Indenture
referred to in this Security, and directs that the shares issuable and
deliverable upon such conversion, together with any check in payment for
fractional shares and any Securities representing any unconverted principal
amount hereof, be issued and delivered to the registered holder hereof unless a
different name has been indicated below.  If shares or any portion of this
Security not converted are to be issued in the name of a person other than the
undersigned, the undersigned will pay all transfer taxes payable with respect
thereto.  Any amount required to be paid to the undersigned on account of
interest (including Additional Amounts, if any) accompanies this Security.


Dated:________________    Your Name: __________________________________________
                          (Print your name exactly as it appears on the face of
                          this Security)

                          Your Signature: _____________________________________
                          (Sign exactly as your name appears on the face of this
                          Security)

                          Signature Guarantee*: _______________________________

                          Social Security or other Taxpayer
                          Identification Number:


     Principal amount to be converted (if less than all):  $


     * Participant in a recognized Signature Guarantee Medallion Program (or
other signature guarantor acceptable to the Trustee).

                                     A-18
<PAGE>

Fill in for registration of shares (if to be issued) and Securities (if to be
delivered) other than to and in the name of the registered holder:




          _____________________________________________
          (Name)

          _____________________________________________
          (Street Address)

          _____________________________________________
          (City, State and Zip Code)

                                     A-19
<PAGE>

                    NOTICE OF EXERCISE OF REPURCHASE RIGHT

TO:  CuraGen Corporation
     555 Long Wharf Drive
     New Haven, Connecticut 06511

          The undersigned registered owner of this Security hereby irrevocably
acknowledges receipt of a notice from CuraGen Corporation (the "Company") as to
the occurrence of a Change of Control with respect to the Company and requests
and instructs the Company to repay the entire principal amount of this Security,
or the portion thereof (the principal amount of which is an integral multiple of
$1,000) below designated, in accordance with the terms of the Indenture referred
to in this Security, together with interest (including Additional Amounts, if
any) accrued and unpaid to, but excluding, such date, to the registered holder
hereof, in cash.

Dated: ________________  Your Name: ___________________________________________
                         (Print your name exactly as it appears on the face of
                         this Security)

                         Your Signature: ______________________________________
                         (Sign exactly as your name appears on the face of this
                         Security)

                         Signature Guarantee:* ________________________________

                         Social Security or other Taxpayer
                         Identification Number:

     Principal amount to be repaid (if less than all):  $

___________________________
*   Participant in a recognized Signature Guarantee Medallion Program (or other
signature guarantor acceptable to the Trustee).

                                     A-20
<PAGE>

               SCHEDULE OF EXCHANGES FOR PHYSICAL SECURITIES/1/


          The following exchanges of a part of this Global Security for Physical
Securities have been made:

<TABLE>
<CAPTION>
                                                                          Principal Amount of this
                   Amount of decrease in         Amount of increase in         Global Security            Signature of
                    Principal Amount of           Principal Amount of      following such decrease   Authorized officer of
Date of Exchange   this Global Security          this Global Security           (or increase)               Trustee
----------------   --------------------          --------------------           -------------               -------
<S>                <C>                           <C>                      <C>                        <C>
</TABLE>

_________________________
/1/   This schedule should be included only if the Security is issued in global
                                     form.

                                     A-21
<PAGE>

1/   Insert if the Security is a Global Security.
-
2/   Insert if the Security is a Restricted Security.
-

3/   Insert if the Security is a Physical Security.
-

4/   Insert "Cede & Co." if the Security is a Global Security.

                                     A-22
<PAGE>

                                                                       EXHIBIT B

                   FORM OF INVESTMENT REPRESENTATION LETTER

               (INSTITUTIONAL ACCREDITED INVESTOR CERTIFICATES)


The Chase Manhattan Bank,
 as Trustee
450 West 33rd Street, 10th Floor
New York, NY  10001-2967
Attention:   Capital Markets Fiduciary Services

      Re:  6.00% Convertible Subordinated Debentures due 2007 of CuraGen
           Corporation (CUSIP Nos. 23126RAA9 and 23126RAB7) (the "Securities")

Ladies and Gentlemen:

      In connection with the undersigned's proposed purchase of $____________
aggregate principal amount of 6.00% Convertible Subordinated Debentures due 2007
(the "Debentures") of CuraGen Corporation (the "Company"), the undersigned
confirms, represents and warrants that:

          (1) The undersigned is (a) an institutional "accredited investor"
     within the meaning of Rule 501(a)(1), (2), (3) or (7) under the Securities
     Act of 1933, as amended (the "Securities Act") or an entity in which all of
     the equity owners are accredited investors within the meaning of Rule 501
     under the Securities Act (an "Institutional Accredited Investor") or (b) an
     "accredited investor" within the meaning of Rule 501(a)(4), (5) or (6)
     under the Securities Act (a "Non-institutional Accredited Investor").

          (2) (A) Any purchase of the Securities by the undersigned will be for
    the undersigned's own account or for the account of one or more other
    Institutional Accredited Investors or Non-institutional Accredited Investors
    or as fiduciary for the account of one or more trusts, each of which is an
    "accredited investor" within the meaning of Rule 501(a)(7) under the
    Securities Act and for each of which the undersigned exercises sole
    investment discretion or (B) the undersigned is a "bank", within the meaning
    of Section 3(a)(2) of the Securities Act, or a "savings and loan
    association" or other institution described in Section 3(a)(5)(A) of the
    Securities Act that is acquiring the Securities as fiduciary for the account
    of one or more institutions for which the undersigned exercises sold
    investment discretion.

          (3) In the event that the undersigned is an Institutional Accredited
     Investor that is purchasing Securities, the undersigned will acquire
     Securities having a minimum aggregate principal amount of $100,000 for its
     own account or for any separate account for which the undersigned is
     acting.

          (4) In the event that the undersigned is a Non-institutional
     Accredited Investor that is purchasing Securities, the undersigned will
     acquire Securities having a minimum

                                      B-1
<PAGE>

     aggregate principal amount of $250,000 for its own account or for any
     separate account for which the undersigned is acting.

          (5) The undersigned has such knowledge and experience in financial and
     business matters that the undersigned is capable of evaluating the merits
     and risks of its investment in the Securities, and the undersigned and any
     accounts for which it is acting is each able to bear the economic risk of
     its or their investment.

          (6) The undersigned is not acquiring the Securities with a view to
     distribution thereof or with any present intention of offering or selling
     any Securities or the Common Stock of the Company issuable upon conversion
     thereof, except as permitted below; provided that the disposition of the
     undersigned's property and the property of any accounts for which the
     undersigned is acting as fiduciary will remain at all times within the
     undersigned's control.

          (7) The undersigned understands that the Securities and the shares of
     Common Stock issuable upon conversion thereof have not been registered
     under the Securities Act or any applicable state securities laws.

          (8) The undersigned agrees, on its own behalf and on behalf of each
     account for which the undersigned acquires any Securities, that if in the
     future the undersigned decides to resell or otherwise transfer such
     Securities within two years after the original issuance of the Securities,
     such Securities may be resold or otherwise transferred only:

              (A) to the Company or any subsidiary thereof;

              (B) to a person which is a "qualified institutional buyer" (as
  defined in Rule 144A under the Securities Act) in compliance with Rule 144A
  under the Securities Act;

              (C) to a non-U.S. person outside the United States in compliance
  with Regulation S under the Securities Act;

              (D) pursuant to an exemption from registration under the
  Securities Act to an Institutional Accredited Investor that is purchasing
  Securities having an aggregate principal amount of at least $100,000 (or a
  number of shares of Common Stock at least equal to $100,000 divided by
  $127.6550 (the initial conversion price)) or to a Non-institutional Accredited
  Investor that is purchasing Securities having an aggregate principal amount of
  at least $250,000 (or a number of shares of Common Stock at least equal to
  $250,000 divided by $127.6550 (the initial conversion price)), and that, in
  either case, prior to such transfer, furnishes to you (or the transfer agent,
  as the case may be) a signed letter substantially in the form of this letter;

              (E) pursuant to the exemption from registration provided by Rule
  144 under the Securities Act (if available); or

                                      B-2
<PAGE>

               (F) pursuant to a registration statement which has been declared
  effective under the Securities Act (and continues to be effective at the time
  of such transfer).

The undersigned further agrees to provide to any person purchasing any of the
Securities from us a notice advising such purchaser that resales of the
Securities are restricted as stated herein.

          (9)  The undersigned understands that, on any proposed resale of any
Securities, the undersigned will be required to furnish to you and the Company
such certifications, legal opinions and other information as you and the Company
may reasonably require to confirm that the proposed sale complies with the
foregoing restrictions. The undersigned further understands that the Securities
purchased by the undersigned will be in definitive form and will bear a legend
to the foregoing effect.

          (10) With respect to the certificates representing Securities the
undersigned is purchasing, the undersigned understands that such certificates
will be in definitive registered form and that the notification requirement
referred to in (9) above requires that, until the expiration of the holding
period with respect to sales of the Securities under clause (k) of Rule 144
under the Securities Act, such Securities will bear a legend substantially to
the following effect:

"THE SECURITY EVIDENCED BY THIS CERTIFICATE HAS NOT BEEN REGISTERED
UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"),
OR ANY STATE SECURITIES. BY ACQUISITION HEREOF, THE HOLDER:

     (1) REPRESENTS THAT (A) IT IS A "QUALIFIED INSTITUTIONAL BUYER"
     AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT, (B) IT IS A NON-
     U.S. PERSON WHO IS ACQUIRING THIS SECURITY IN AN OFFSHORE
     TRANSACTION MEETING THE REQUIREMENTS OF RULE 903 OR RULE 904 OF
     REGULATION S UNDER THE SECURITIES ACT; OR (C) IT IS AN
     INSTITUTIONAL "ACCREDITED INVESTOR" AS DEFINED IN RULE 501(a)(1),
     (2), (3) OR (7) UNDER THE SECURITIES ACT (AN "INSTITUTIONAL
     ACCREDITED INVESTOR") THAT IS PURCHASING AT LEAST $100,000 IN
     AGGREGATE PRINCIPAL AMOUNT OF DEBENTURES OR AN "ACCREDITED
     INVESTOR" AS DEFINED IN RULE 501(a)(4), (5) or (6) UNDER THE
     SECURITIES ACT (A "NON-INSTITUTIONAL ACCREDITED INVESTOR") THAT
     IS PURCHASING AT LEAST $250,000 IN AGGREGATE PRINCIPAL AMOUNT OF
     DEBENTURES;

     (2) AGREES THAT NEITHER THE SECURITY EVIDENCED HEREBY NOR THE
     COMMON STOCK ISSUABLE UPON CONVERSION OF SUCH SECURITY MAY BE
     RESOLD, PLEDGED
                                      B-3
<PAGE>

     OR OTHERWISE TRANSFERRED (X) WITHIN TWO YEARS AFTER THE ORIGINAL
     ISSUANCE OF THE SECURITY EVIDENCED HEREBY OR (Y) BY A HOLDER THAT
     WAS AN AFFILIATE OF THE COMPANY AT ANY TIME DURING THE THREE
     MONTHS PRECEDING THE DATE OF SUCH RESALE, PLEDGE OR TRANSFER, IN
     EITHER CASE, EXCEPT (A) TO THE COMPANY OR ANY SUBSIDIARY THEREOF,
     (B) TO A QUALIFIED INSTITUTIONAL BUYER IN COMPLIANCE WITH RULE
     144A UNDER THE SECURITIES ACT, (C) TO A NON-U.S. PERSON OUTSIDE
     OF THE UNITED STATES IN COMPLIANCE WITH REGULATIONS S UNDER THE
     SECURITIES ACT, (D) PURSUANT TO AN EXEMPTION FROM REGISTRATION
     UNDER THE SECURITIES ACT TO AN INSTITUTIONAL ACCREDITED INVESTOR
     THAT IS PURCHASING DEBENTURES IN AGGREGATE PRINCIPAL AMOUNT OF AT
     LEAST $100,000 OR TO A NON-INSTITUTIONAL ACCREDITED INVESTOR THAT
     IS PURCHASING DEBENTURES IN AGGREGATE PRINCIPAL AMOUNT OF AT
     LEAST $250,000, AND THAT, IN EITHER CASE, PRIOR TO SUCH TRANSFER,
     FURNISHES TO THE CHASE MANHATTAN BANK, AS TRUSTEE (OR ANY
     SUCCESSOR TRUSTEE, AS APPLICABLE), A SIGNED LETTER CONTAINING
     CERTAIN REPRESENTATIONS AND WARRANTIES RELATING TO THE
     RESTRICTIONS ON TRANSFER OF THE SECURITY EVIDENCED HEREBY (THE
     FORM OF LETTER CAN BE OBTAINED FROM SUCH TRUSTEE), (E) PURSUANT
     TO THE EXEMPTION FROM REGISTRATION PROVIDED BY RULE 144 UNDER THE
     SECURITIES ACT (IF AVAILABLE) OR (F) PURSUANT TO A REGISTRATION
     STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES
     ACT AND WHICH CONTINUES TO BE EFFECTIVE AT THE TIME OF SUCH
     TRANSFER; AND

     (3) AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THE
     SECURITY EVIDENCED HEREBY IS TRANSFERRED (OTHER THAN A TRANSFER
     PURSUANT TO CLAUSE 2(F) ABOVE) A NOTICE SUBSTANTIALLY TO THE
     EFFECT OF THIS LEGEND.

IN CONNECTION WITH ANY TRANSFER OF THE SECURITY EVIDENCED HEREBY
WITHIN TWO YEARS AFTER THE ORIGINAL ISSUANCE OF SUCH SECURITY (OTHER
THAN A TRANSFER PURSUANT TO CLAUSE (2)(F) ABOVE), THE HOLDER MUST
CHECK THE APPROPRIATE BOX SET FORTH ON THE REVERSE HEREOF RELATING TO
THE MANNER OF SUCH TRANSFER AND SUBMIT THIS CERTIFICATE TO THE TRUSTEE
(OR ANY SUCCESSOR TRUSTEE, AS APPLICABLE). IF THE PROPOSED TRANSFER IS
PURSUANT TO
                                      B-4
<PAGE>

     CLAUSE (2)(B), 2(C), 2(D) OR 2(E) ABOVE, THE HOLDER MUST, PRIOR
     TO SUCH TRANSFER, FURNISH TO THE TRUSTEE (OR ANY SUCCESSOR
     TRUSTEE, AS APPLICABLE), SUCH 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. THIS LEGEND WILL BE REMOVED
     UPON THE EARLIER OF THE TRANSFER OF THE SECURITY EVIDENCED HEREBY
     PURSUANT TO CLAUSE (2)(F) ABOVE OR THE EXPIRATION OF TWO YEARS
     FROM THE ORIGINAL ISSUANCE OF THE SECURITY EVIDENCED HEREBY. AS
     USED HEREIN, THE TERMS "UNITED STATES" AND "U.S. PERSON" HAVE THE
     MEANINGS GIVEN TO THEM BY REGULATION S UNDER THE SECURITIES ACT."

          (11) With respect to the certificates representing shares of Common
     Stock issuable upon conversion of the Securities, the undersigned
     understands that the notification requirement referred to in (9) above
     requires that, until the expiration of the holding period with respect to
     sales of such Common Stock under clause (k) of Rule 144 under the
     Securities Act, such certificates will bear a legend substantially to the
     effect set forth in Section 2.3(a)(ii) of the Indenture and that a copy of
     such legend may be obtained from the Trustee.

          Each of the Company, the Trustee and the initial purchasers of the
Securities are entitled to rely upon this letter and are irrevocably authorized
to produce this letter or a copy hereof to any interested party in any
administrative or legal proceedings or official inquiry with respect to the
matters covered hereby.

                                             Very truly yours,

                                             By: _______________________________
                                                 Name:
                                                 Title:
                                                 Address:

                                      B-5