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                                                                     EXHIBIT 4.2


          THIS SUPPLEMENTAL INDENTURE, dated as of May 16, 2001 (this
"Supplemental Indenture"), is between COOPER CAMERON CORPORATION, a corporation
duly organized and existing under the laws of the State of Delaware (the
"Company"), and Bank One Trust Company, National Association (as successor to
The First National Bank of Chicago), a national banking association (the
"Trustee").

                            RECITALS OF THE COMPANY

          The Company has duly authorized the execution and delivery of the
Indenture dated as of May 8, 1998, between the Company and the Trustee (as
amended, the "Indenture").

          The Company wishes to issue a separate series of Securities pursuant
to the Indenture to be designated the "Zero Coupon Convertible Senior Debentures
due 2021" (the "Debentures").

          Concurrently herewith, the Company is issuing a series of Securities
(as such term is defined in the Indenture) pursuant to the Indenture to be
designated the "1.75% Convertible Senior Debentures due 2021."

          The Company desires to amend, and hereby directs the Trustee to enter
into the amendment of, the Indenture by this Supplemental Indenture in order to
add certain provisions to the Indenture to provide for the issuance of the
Debentures.

          The Company has duly authorized the execution and delivery of this
Supplemental Indenture and all other things necessary to make the Indenture, as
hereby supplemented and amended, a valid indenture and agreement according to
its terms have been done.

          NOW, THEREFORE, THIS SUPPLEMENTAL 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 or of series
thereof, as follows:

                                  ARTICLE ONE

                      TERMS AND ISSUANCE OF THE DEBENTURES

SECTION 101.  Designation of Debentures; Establishment of Form.

          There shall be a series of Securities designated "Zero Coupon
Convertible Senior Debentures Due 2021" of the Company (the "Debentures"), and
the form thereof shall be substantially as set forth in Annex A hereto, which is
incorporated into and shall be deemed a part of this Supplemental Indenture, in
each case with such appropriate insertions, omissions, substitutions and other
variations as are required or permitted by the Indenture, and may have such
letters, numbers or other marks of identification and such legends or
endorsements placed thereon as may be required to comply with the rules of any
securities exchange or as may,
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consistently herewith, be determined by the officers of the Company executing
such Debentures, as evidenced by their execution of the Debentures.

          The Debentures will initially be issued in permanent global form,
substantially in the form set forth in Annex A hereto (the "Global Securities").
Each Global Security shall represent such of the Outstanding Debentures as shall
be specified therein and shall provide that it shall represent the aggregate
amount of Outstanding Debentures from time to time endorsed thereon and that the
aggregate amount of Outstanding Debentures represented thereby may from time to
time be reduced to reflect exchanges and redemptions.  Any endorsement of a
Global Security to reflect the amount, or any increase or decrease in the
amount, of Outstanding Debentures represented thereby shall be made by the
Trustee in accordance with written instructions or such other written form of
instructions as is customary for the Depositary, from the Depositary or its
nominee on behalf of any Person having the beneficial interest in the Global
Security.

          The Company initially appoints The Depository Trust Company to act as
Depositary with respect to the Global Securities.

          The Company initially appoints the Trustee to act as Paying Agent and
Conversion Agent with respect to the Debentures.

SECTION 102.  Amount.

     (a) The Trustee shall authenticate and deliver Debentures for original
issue in an aggregate Principal Amount of up to $320,756,000 upon Company Order
for the authentication and delivery of Debentures, without any further action by
the Company.  The aggregate Principal Amount of Debentures that may be
authenticated and delivered under the Indenture may not exceed the amount set
forth in the foregoing sentence, except for Debentures authenticated and
delivered upon registration of transfer of, or in exchange for, or in lieu of,
other Debentures pursuant to Section 204, 304, 305, 306, 906, 1106, 1112, 1402
or 1406 of the Indenture.

     (b) The Company may not issue new Debentures to replace Debentures that it
has paid or delivered to the Trustee for cancellation or that any Holder has
converted pursuant to Article Fourteen.

SECTION 103.  Accrual of Original Issue Discount; Interest.

          The Debentures shall be Original Issue Discount Securities.  Original
Issue Discount shall accrue with respect to the Debentures at the rate set forth
under the caption "Interest" in the Debentures, commencing on the Issue Date of
the Debentures.  Except as provided under the caption "Tax Event" in the
Debentures and in Section 1406, there shall be no periodic payments of interest
on the Debentures.

SECTION 104.  Denominations.

          The Debentures shall be in fully registered form without coupons in
denominations of $1,000 of Principal Amount or any integral multiple thereof.

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SECTION 105.  Place of Payment.

          The Place of Payment for the Debentures and the place or places where
the Debentures may be surrendered for registration of transfer, exchange,
repurchase, redemption or conversion and where notices may be given to the
Company in respect of the Debentures is at the office of the Trustee in New
York, New York and at the agency of the Trustee maintained for that purpose at
the office of the Trustee; provided that payment of interest may be made at the
option of the Company by check mailed to the address of the person entitled
thereto as such address shall appear in the Security Register or by wire
transfer of immediately available funds to the accounts specified by the holder
of such Debentures.

SECTION 106.  Redemption.

          (a) There shall be no sinking fund for the retirement of the
Debentures.

          (b) The Company, at its option, may redeem the Debentures in
accordance with the provisions of and at the Redemption Prices set forth under
the captions "Optional Redemption" and "Notice of Redemption; Procedures" in the
Debentures and in accordance with the provisions of the Indenture, including,
without limitation, Article Eleven.

SECTION 107.  Conversion.

          The Debentures shall be convertible in accordance with the provisions
and at the Conversion Rate set forth under the caption "Conversion" in the
Debentures and in accordance with the provisions of the Indenture, including,
without limitation, Article Fourteen.

SECTION 108.  Maturity.

          The date on which the principal of the Debentures is payable, unless
accelerated pursuant to the Indenture, shall be May 17, 2021.

SECTION 109.  Repurchase of Debenture.

          (a) The Company shall, at the option of the Holders thereof,
repurchase the Debentures in accordance with the provisions and at the Purchase
Prices set forth under the caption "Repurchase at the Option of the Holder;
Repurchase at the Option of the Holder Upon a Fundamental Change" in the
Debentures and in accordance with the provisions of the Indenture, including,
without limitation, Section 1108.

          (b) The Company, at the option of the Holders thereof, shall
repurchase the Debentures in accordance with the provisions of and at the
Fundamental Change Purchase Prices set forth under the caption "Repurchase at
the Option of the Holder; Repurchase at the Option of the Holder Upon a
Fundamental Change" in the Debentures and in accordance with the provisions of
the Indenture, including, without limitation, Article Eleven.

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SECTION 110.  Amount Due Upon Event of Default.

          The portion of the principal amount specified in the terms of the
Debentures as contemplated by Section 502 of the Indenture to be payable upon
acceleration of maturity of the Debentures shall be the unpaid Issue Price plus
accrued Original Issue Discount through the date of acceleration, if any (or, if
the Debentures have been converted to interest-bearing Debentures pursuant to
Section 1406, the Restated Principal Amount plus accrued and unpaid interest
from the date of conversion to the acceleration date).

SECTION 111.  Discharge of Liability on Debentures.

          Section 403 of the Indenture shall be applicable to the Debentures.

SECTION 112.  Other Terms of Debentures.

          Without limiting the foregoing provisions of this Article One, the
terms of the Debentures shall be as set forth in the form of Debentures set
forth in Annex A hereto and as provided in the Indenture.

                                  ARTICLE TWO

                          AMENDMENTS TO THE INDENTURE

     The amendments contained herein shall apply to Debentures only and not to
any other series of Security issued under the Indenture and any covenants
provided herein are expressly being included solely for the benefit of the
Debentures. These amendments shall be effective for so long as there remains
Debentures Outstanding.

SECTION 201.  Definitions.

          The following terms and their respective meanings are hereby added to
the Indenture at the end of Section 101 thereof with respect to the Debentures
only:

                    "Beneficial Owner" has the meaning specified in Section
          1109(a).

                    "Capital Stock" or "capital stock" of any Person means any
          and all shares, interests, partnership interests, participations,
          rights or other equivalents (however designated) of such Person's
          equity interest (however designated) issued by that Person.

                    "Cash" has the meaning specified in Section 1108(b).

                    "Common Stock" means any stock of any class of the Company
          (including, without limitation, the Company's common stock, par value
          $.01 per share) which has no preference

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          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.

                    "Company Notice Date" has the meaning specified in Section
          1108(c).

                    "Conversion Date" has the meaning specified in Section 1402.

                    "Conversion Rate" has the meaning specified in Section 1401.

                    "Defaulted Interest" has the meaning specified in Section
          1406(d).

                    "Distributed Securities" has the meaning specified in
          Section 1409(a).

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

                    "Expiration Time" has the meaning specified in Section
          1409(c).

                    "Fundamental Change" has the meaning specified in Section
          1109(a).

                    "Fundamental Change Person" has the meaning specified in
          Section 1109(a).

                    "Fundamental Change Purchase Date" has the meaning specified
          in Section 1109(b).

                    "Fundamental Change Purchase Notice" has the meaning
          specified in Section 1109(c).

                    "Fundamental Change Purchase Price" has the meaning
          specified in Section 1109(b).

                    "Global Securities" has the meaning specified in Section
          101.

                    "Group" has the meaning specified in Section 1109(a).

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                    "Interest Payment Date" has the meaning specified in Section
          1406(a).

                    "Issue Date" of any Security means the date on which the
          Security was originally issued or deemed issued as set forth on the
          face of the Security.

                    "Issue Price" of any Security means, in connection with the
          original issuance of such Security, the initial issue price at which
          the Security is issued as set forth on the face of the Security.

                    "Market Price" has the meaning specified in Section 1108(d).

                    "Option Exercise Date" has the meaning specified in Section
          1406(a).

                    "Original Issue Discount" of any Security means the
          difference between the Issue Price and the Principal Amount of the
          Security as set forth on the face of the Security. For purposes of
          this Indenture and the Securities, accrual of Original Issue Discount
          shall be calculated on the basis of a 360-day year consisting of
          twelve 30-day months.

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

                    (i)    Debentures theretofore cancelled by the Trustee or
          delivered to the Trustee for cancellation;

                    (ii)   Debentures for whose payment, repurchase or
          redemption money or Common Stock of the Company in the necessary
          amount has been theretofore 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 Debentures; provided that, if such
          Debentures are to be redeemed, notice of such redemption has been duly
          given pursuant to this Indenture or provision therefor satisfactory to
          the Trustee has been made;

                    (iii)  Debentures which have been cancelled pursuant to
          Section 309 or in exchange for or in lieu of which other Debentures
          have been authenticated and delivered pursuant to this Indenture,
          other than any such Debentures in respect of which there shall have
          been presented to the Trustee proof satisfactory to

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          it that such Debentures are held by a bona fide purchaser in whose
          hands such Debentures are valid obligations of the Company; and

                    (iv)   Debentures converted for Common Stock of the Company
          pursuant to Article Fourteen;

          provided, however, that in determining whether the Holders of the
          requisite principal amount of the Outstanding Debentures have given
          any request, demand, authorization, direction, notice, consent or
          waiver hereunder, Debentures owned by the Company or any other obligor
          upon the Debentures or any Affiliate of the Company or of such other
          obligor shall be disregarded and deemed not to be Outstanding, except
          that, in determining whether the Trustee shall be protected in relying
          upon any such request, demand, authorization, direction, notice,
          consent or waiver, only Debentures which the Trustee knows to be so
          owned shall be so disregarded.  Debentures so owned which have been
          pledged in good faith may be regarded as Outstanding if the pledgee
          establishes to the satisfaction of the Trustee the pledgee's right so
          to act with respect to such Debentures and that the pledgee is not the
          Company or any other obligor upon the Debentures or any Affiliate of
          the Company or of such other obligor.

                    "Principal Amount" of a Debenture means the principal amount
          at maturity as set forth on the face of the Debenture.

                    "Purchase Date" has the meaning specified in Section
          1108(a).

                    "Purchase Price" has the meaning specified in Section
          1108(a).

                    "Purchase Notice" has the meaning specified in Section
          1108(a).

                    "Purchased Shares" has the meaning specified in Section
          1409(c).

                    "Redemption Date" means a date specified for redemption of
          the Securities (other than repurchase upon a Fundamental Change at the
          option of the Holder) in accordance with the terms of the Securities
          and Section 1101 of this Indenture.

                    "Registered Security" means any Security in the form
          established pursuant to Section 201 which is registered in the
          Security Register.

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                    "Regular Record Date" has the meaning specified in Section
          1406(a).

                    "Restated Principal Amount" has the meaning specified in
          Section 1406(a).

                    "Sale Price" has the meaning specified in Section 1108(d).

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

                    "Tax Event" means that the Company shall have received an
          opinion from independent tax counsel experienced in such matters to
          the effect that, as a result of (a) any amendment to, or change
          (including any announced prospective change) in, the laws (or any
          regulations thereunder) of the United States or any political
          subdivision or taxing authority thereof or therein or (b) any
          amendment to, or change in, an interpretation or application of such
          laws or regulations by any legislative body, court, governmental
          agency or regulatory authority, there is more than an insubstantial
          risk that interest, including Original Issue Discount, payable on the
          Securities either (i) would not be deductible on a current accrual
          basis or (ii) would not be deductible under any other method, in
          either case, in whole or in part, by the Company (by reason of
          deferral, disallowance or otherwise) for United States Federal income
          tax purposes.

                    "Tax Event Date" has the meaning specified in Section
          1406(a).

                    "Tender Expiration Time" has the meaning specified in
          Section 1409(d).

                    "Tender Purchased Shares" has the meaning specified in
          Section 1409(d).

                    "Trading Day" means a day during which trading in securities
          generally occurs on the New York Stock Exchange or, if the applicable
          security is not quoted on the New York Stock Exchange, on The NASDAQ
          National Market, or if the applicable security is not listed on The
          NASDAQ National Market, on the principal other national or regional
          securities exchange on which the applicable security is then listed
          or, if the applicable security is not listed on a national or regional
          securities exchange, on the principal other market on which the
          applicable security is then traded.

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                    "Trigger Event" has the meaning specified in Section 1420.

                    "Unissued Shares" means shares of Voting Stock not
          outstanding that are subject to options, warrants, rights to purchase
          or conversion privileges exercisable within 60 days of the date of
          determination of a Fundamental Change.

                    "Voting Stock" means any class or classes of Capital Stock
          pursuant to which the holders thereof under ordinary circumstances
          have the power to vote in the election of the board of directors,
          managers or trustees of any Person (or other Persons performing
          similar functions), irrespective of whether or not, at the time,
          Capital Stock of any other class or classes shall have, or might have,
          voting power by reason of the happening of any contingency.

SECTION 202.  Registration, Registration of Transfer and Exchange.

          The Indenture shall be amended by replacing the seventh paragraph of
Section 305 with the following paragraph:

                    The Company shall not be required (i) to issue, register the
          transfer of or exchange the Securities of any series during a period
          beginning at the opening of business 15 days before the day of the
          mailing of a notice of redemption of Securities of that series
          selected for redemption and ending at the close of business on the day
          of such mailing, (ii) to register the transfer of or exchange any
          Debenture so selected for redemption in whole or in part, except the
          unredeemed portion of any Security being redeemed in part, or (iii) to
          exchange or register a transfer of any Debenture or portions thereof
          in respect of which a Fundamental Change Purchase Notice or Purchase
          Notice has been delivered and not withdrawn by the Holder thereof
          (except, in the case of the purchase of a Debenture in part, the
          portion not to be purchased).

SECTION 203.  Mutilated, Destroyed, Lost and Stolen Securities.

          The Indenture shall be amended by replacing the third paragraph of
Section 306 with the following paragraph:

                    In case any such mutilated, destroyed, lost or stolen
          Security has or is about to become due and payable, or is about to be
          redeemed or purchased by the Company upon a Fundamental Change
          pursuant to Article Eleven or purchased by the Company on a Purchase
          Date pursuant to Section 1108, the Company in its

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          discretion may, instead of issuing a new Security, pay such Security.

SECTION 204.  Payment of Interest; Interest Rights Preserved.

          The Indenture shall be amended by inserting the following paragraph
before the final paragraph in Section 307:

                    In the event the Company exercises its option pursuant to
          Section 1406, then in the case of any Debenture or portion thereof
          which is surrendered for conversion after the close of business on the
          Regular Record Date immediately preceding any Interest Payment Date
          and prior to the opening of business on such next succeeding Interest
          Payment Date (unless such Debenture or portion thereof which is being
          surrendered for conversion has been called for redemption on a
          Redemption Date within such period), interest whose Stated Maturity is
          on such Interest Payment Date shall be payable on such Interest
          Payment Date notwithstanding such conversion, and such interest
          (whether or not punctually paid or duly provided for) shall be paid to
          the Person in whose name that Debenture (or one or more Predecessor
          Securities) is registered at the close of business on such Regular
          Record Date; provided, however, that such payment of interest shall be
          subject to the payment to the Company by the Holder of such Debenture
          or portion thereof surrendered for conversion (such payment to
          accompany such surrender) of an amount equal to the amount of such
          interest, in accordance with Section 1402. Except as otherwise
          provided in the immediately preceding sentence, in the case of any
          Debenture which is converted, interest whose Stated Maturity is after
          the date of conversion of such Debenture shall not be payable.

SECTION 205.  Satisfaction and Discharge of Indenture.

          The Indenture shall be amended by replacing the last paragraph of
Section 401 with the following paragraph:

                    Notwithstanding the satisfaction and discharge of this
          Indenture with respect to the Outstanding Securities of such series
          pursuant to this Section 401, the obligations of the Company to the
          Trustee under Section 607, the obligations of the Trustee to any
          Authenticating Agent under Section 614 and, except for a discharge
          pursuant to subclause (A) of clause (1) of this Section 401, the
          obligations of the Company under Sections 305, 306, 404, 610(e), 701,
          1001, 1002 and 1108 and Articles Eleven and Fourteen and the
          obligations of the Trustee under Section 402 and the last paragraph of
          Section 1003 shall survive.

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SECTION 206.  Discharge of Liability on Securities of Any Series.

          The Indenture shall be amended by replacing the last paragraph of
Section 403 with the following paragraph:

                    Upon the satisfaction of the conditions set forth in this
          Section with respect to all the Outstanding Securities of any series,
          the terms and conditions of such series, including the terms and
          conditions with respect thereto set forth in this Indenture, shall no
          longer be binding upon, or applicable to, the Company; provided that
          the Company shall not be discharged from (a) any payment obligations
          in respect of Securities of such series that are deemed not to be
          Outstanding under clause (iii) of the definition thereof if such
          obligations continue to be valid obligations of the Company under
          applicable law or (b) any obligations pursuant to Section 305, 306 or
          1108 or Articles Eleven and Fourteen.

SECTION 207.  Unconditional Right of Holders to Receive Principal, Premium and
Interest.

          Section 508 of the Indenture shall be amended by replacing that
section with the following:

          Section 508.  Unconditional Right of Holders to Receive Principal,
          Premium and Interest.

                    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 (subject to Section 307) interest on the Stated Maturity or
          Maturities expressed in such Security (or in the case of redemption,
          to receive the Redemption Price on the Redemption Date, in the case of
          a repurchase, to receive the Purchase Price on the Purchase Date, or
          in the case of a Fundamental Change, to receive the Fundamental Change
          Purchase Price on the Fundamental Change Purchase Date) and to
          institute suit for the enforcement of any such payment on or after
          such respective dates, and such rights shall not be impaired without
          the consent of such Holder.

SECTION 208.  Consolidation, Merger and Sale.

          The Indenture shall be amended by inserting "and shall have provided
for conversion rights in accordance with Section 1415" at the end of Section
801(1).

SECTION 209.  Supplemental Indentures Without Consent of Holders.

          Section 901 of the Indenture shall be amended by changing the period
at the end thereof to "; or" and by inserting the following paragraph after such
insertion:

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                    (9) to make provision with respect to the conversion rights,
          if any, to Holders of Debentures pursuant to the requirements of
          Article Fourteen hereof.

SECTION 210.  Supplemental Indenture with Consent of Holder.

          (a) Section 902 of the Indenture shall be amended by inserting "or
adversely affect the right to convert any Debenture as provided in Article
Fourteen, or adversely affect the right to require the Company to repurchase the
Debentures as provided in Section 1108, or" at the end of Section 902(1).

          (b) Section 902 of the Indenture shall be further amended by replacing
the period (.) at the end of Section 902(3) with ", or" and inserting the
following after the end of Section 902(3):

                    (4)  reduce the Redemption Price, Purchase Price or
          Fundamental Change Purchase Price of any Security; or

                    (5)  impair the right to institute suit for payment under,
          or conversion of, the Debentures; or

                    (6)  change any obligation of the Company to maintain an
          office or agency in the places and for the purposes specified in the
          Indenture.

SECTION 211.  Maintenance of Office or Agency.

          The first paragraph of Section 1002 of the Indenture is amended by
changing the first sentence thereof to read in its entirety as follows:

                    The Company will maintain in each Place of Payment for the
          Debentures an office or agency where Debentures may be presented or
          surrendered for payment, where Debentures may be surrendered for
          registration of transfer or exchange, where Debentures may be
          surrendered for conversion and where notices and demands to or upon
          the Company in respect of the Debentures and this Indenture may be
          served.  The Company will give prompt written notice to the Trustee of
          the location, and any change in the location, of such office or
          agency. If at any time the Company shall fail to maintain any such
          required office or agency or shall fail to furnish the Trustee with
          the address thereof, such presentations, surrenders, notices and
          demands may be made or served at the Corporate Trust Office of the
          Trustee, and the Company hereby appoints the Trustee as its agent to
          receive all such presentations, surrenders, notices and demands.


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SECTION 212.  Redemption.

          The following is hereby added to the Indenture, replacing the existing
Article Eleven of the Indenture, with respect to the Debentures only:

                                 ARTICLE ELEVEN


                            REDEMPTION AND PURCHASES

          SECTION 1101.  Right To Redeem; Notices To Trustee.

                     The Company, at its option, may redeem the Securities in
          accordance with paragraph 5 of the Securities and the provisions of
          this Indenture. If the Company elects to redeem Securities pursuant to
          paragraph 5 of the Securities, it shall notify the Trustee in writing
          of the Redemption Date, the Principal Amount of Securities to be
          redeemed and the Redemption Price.

          SECTION 1102.  Selection of Securities to be Redeemed.

                     If less than all the Securities held in definitive form are
          to be redeemed pursuant to Section 1101, the Trustee shall select the
          definitive Securities to be redeemed pro rata or by lot or by another
          method the Trustee considers fair and appropriate (as long as such
          method is not prohibited by the rules of any quotation system or
          securities exchange on which the Securities are then quoted or
          listed). The Trustee shall make the selection at least 35 days, but
          not more than 60 days, before the Redemption Date for outstanding
          definitive Securities not previously called for redemption. The
          Trustee may select for redemption portions of the Principal Amount of
          Securities that have denominations larger than $1,000. Securities and
          portions of them the Trustee selects shall be in Principal Amounts of
          $1,000 or an integral multiple of $1,000. Provisions of this Indenture
          that apply to definitive Securities called for redemption also apply
          to portions of definitive Securities called for redemption. The
          Trustee shall notify the Company promptly of the definitive Securities
          or portions of definitive Securities to be redeemed.

                    Any interest in a Security held in global form by and
          registered in the name of the Depositary or its nominee to be redeemed
          in whole or in part will be redeemed in accordance with the procedures
          of the Depositary.

                    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 (to the fullest extent

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          possible) the portion selected for redemption. 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.

          SECTION 1103.  Notice of Redemption.

                    At least 30 days but not more than 60 days before a
          Redemption Date, the Company shall mail a notice of redemption by
          first-class mail, postage prepaid, to each Holder of Securities to be
          redeemed.

                    The notice shall identify the Securities to be redeemed and
          shall state:

                    (1)  the Redemption Date;

                    (2)  the Redemption Price;

                    (3)  the Conversion Rate;

                    (4)  the name and address of the Paying Agent and Conversion
          Agent;

                    (5)  that Securities called for redemption may be converted
          at any time before the close of business on the third Business Day
          prior to the Redemption Date;

                    (6)  that Holders who want to convert Securities must
          satisfy the requirements set forth in paragraph 9 of the Securities;

                    (7)  that Securities called for redemption must be
          surrendered to the Paying Agent to collect the Redemption Price;

                    (8)  if fewer than all the outstanding Securities are to be
          redeemed, the certificate number and Principal Amounts of the
          particular Securities to be redeemed;

                    (9)  that Original Issue Discount on Securities called for
          redemption will cease to accrue on and after the Redemption Date; and

                    (10) the CUSIP number or numbers for the Securities.

                    The notice if mailed in the manner herein provided shall be
          conclusively presumed to have been duly given, whether

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          or not the Holder receives such notice. In any case, failure to give
          such notice by mail or any defect in the notice to the Holder of any
          Security designated for redemption as a whole or in part shall not
          affect the validity of the proceedings for the redemption of any other
          Security.

                    At the Company's written request delivered to the Trustee at
          least 45 days before the Redemption Date (unless a shorter period is
          satisfactory to the Trustee), the Trustee shall give the notice of
          redemption in the Company's name and at the Company's expense.

          SECTION 1104.  Effect of Notice of Redemption.

                    Once notice of redemption is given pursuant to Section 1103,
          Securities called for redemption become due and payable on the
          Redemption Date and at the Redemption Price stated in the notice
          except for Securities which are converted in accordance with the terms
          of this Indenture.

                    Upon the later of the Redemption Date or the date such
          Securities are surrendered to the Paying Agent, such Securities shall
          be paid at the Redemption Price stated in the notice.

          SECTION 1105.  Deposit of Redemption Price.

                    Prior to 10:00 a.m. (local time at the place of payment) on
          the Redemption Date, the Company shall deposit with the Paying Agent
          (or if the Company or an Affiliate of the Company is the Paying Agent,
          shall segregate and hold in trust) money sufficient to pay the
          Redemption Price of all Securities to be redeemed on that date other
          than Securities or portions of Securities called for redemption which
          prior thereto have been delivered by the Company to the Trustee for
          cancellation or have been converted into Common Stock, and on or after
          the Redemption Date (unless the Company shall default in the payment
          of the Securities at the Redemption Price), Original Issue Discount on
          the Securities or portion of Securities called for redemption shall
          cease to accrue and such Securities shall cease after the close of
          business on the third Business Day immediately preceding the
          Redemption Date (except in the circumstances provided in Section 1107,
          immediately preceding the close of business on the Redemption Date) to
          be convertible into Common Stock and on and after the Redemption Date,
          such Securities shall cease to be entitled to any benefit or security
          under this Indenture, and the Holders thereof shall have no right in
          respect of such

                                       15
<PAGE>

          Securities except the right to receive the Redemption Price thereof
          and unpaid interest up to and including the Redemption Date. The
          Paying Agent shall as promptly as practicable return to the Company
          any money, with interest, if any, thereon, not required for that
          purpose because of conversion of Securities. If such money is then
          held by the Company in trust and is not required for such purpose it
          shall be discharged from such trust.

          SECTION 1106.  Securities Redeemed in Part.

                    Upon surrender of a Security that is redeemed in part, the
          Company shall execute and the Trustee shall authenticate and deliver
          to the Holder a new Security in an authorized denomination equal in
          Principal Amount to the unredeemed portion of the Security
          surrendered.

          SECTION 1107.  Conversion Arrangement on Call for Redemption.

                    In connection with any redemption of Securities, the Company
          may arrange for the purchase and conversion into Common Stock of any
          Securities called for redemption by an agreement with one or more
          investment bankers or other purchasers to purchase such Securities by
          paying to the Paying Agent in trust for the Holders, prior to 10:00
          a.m. (local time at the place of payment) on the Redemption Date, an
          amount that, together with any amounts deposited with the Paying Agent
          by the Company for the redemption of the Securities, is not less than
          the Redemption Price up to and including the Redemption Date of such
          Securities. Notwithstanding anything to the contrary contained in this
          Article Eleven, the obligation of the Company to pay the Redemption
          Price of such Securities shall be deemed to be satisfied and
          discharged to the extent such amount is so paid by such purchasers. If
          such an agreement is entered into, any Securities not duly surrendered
          for conversion by the Holders thereof may, at the option of the
          Company, be deemed, to the fullest extent permitted by law, acquired
          by such purchasers from such Holders and (notwithstanding anything to
          the contrary contained in Article Fourteen) surrendered by such
          purchasers for conversion, all immediately prior to the close of
          business on the Redemption Date, subject to payment of the above
          amount as aforesaid. The Paying Agent shall hold and pay to the
          Holders whose Securities are selected for redemption any such amount
          paid to it in the same manner as it would money deposited with it by
          the Company for the redemption of Securities. Without the Paying
          Agent's prior written consent, no arrangement between the Company and
          such purchasers for the purchase and conversion of

                                       16
<PAGE>

          any Securities shall increase or otherwise affect any of the powers,
          duties, responsibilities or obligations of the Paying Agent as set
          forth in this Indenture, and the Company agrees to indemnify the
          Paying Agent from, and hold it harmless against, any loss, liability
          or expense arising out of or in connection with any such arrangement
          for the purchase and conversion of any Securities between the Company
          and such purchasers, including the costs and expenses incurred by the
          Paying Agent in the defense of any claim or liability arising out of
          or in connection with the exercise or performance of any of its
          powers, duties, responsibilities or obligations under this Indenture.

          SECTION 1108.  Purchase of Securities at Option of the Holder.

                    (a) General. Securities shall be purchased by the Company
          pursuant to paragraph 6 of the Securities as of May 17, 2004, May 17,
          2009 and May 17, 2014 (each, a "Purchase Date"), at the purchase price
          specified therein (each, a "Purchase Price") at the option of the
          Holder thereof, upon:

                    (1) delivery to the Paying Agent by the Holder of a written
          notice of purchase (a "Purchase Notice") at any time from the opening
          of business on the date that is 20 Business Days prior to a Purchase
          Date until the close of business on such Purchase Date, stating:

                    (A)  if certificated Securities have been issued, the
          certificate number of the Security which the Holder will deliver to be
          purchased (or, if the Security is not certificated, such other
          identification necessary to comply with appropriate procedures of the
          Depositary);

                    (B)  the portion of the Principal Amount of the Security
          which the Holder will deliver to be purchased, which portion must be
          $1,000 in Principal Amount or a multiple thereof;

                    (C)  that such Security shall be purchased as of the
          Purchase Date pursuant to the terms and conditions specified in
          paragraph 6 of the Securities and the provisions of this Indenture;
          and

                   (D)  if the Company elects, pursuant to a Company Notice, to
          pay the Purchase Price to be paid as of such Purchase Date, in whole
          or in part, in Common Stock but such portion of the Purchase Price
          shall ultimately be payable to such Holder in Cash because any of the
          conditions to the payment of the Purchase Price in Common Stock are
          not satisfied prior to or on

                                       17
<PAGE>

          the Purchase Date, as set forth in Section 1108(d), whether such
          Holder elects (x) to withdraw such Purchase Notice as to some or all
          of the Securities to which such Purchase Notice relates (stating the
          Principal Amount and certificate numbers of the Securities as to which
          such withdrawal shall relate), or (y) to receive Cash in respect of
          the entire Purchase Price for all Securities (or portions thereof) to
          which such Purchase Notice relates; and

                    (2) delivery of such Security to the Paying Agent prior to,
          on or after the Purchase Date (together with all necessary
          endorsements) at the offices of the Paying Agent, such delivery being
          a condition to receipt by the Holder of the Purchase Price therefor;
          provided, however, that such Purchase Price shall be so paid pursuant
          to this Section 1108 only if the Security so delivered to the Paying
          Agent shall conform in all respects to the description thereof in the
          related Purchase Notice.

                    If a Holder, in such Holder's Purchase Notice (and in any
          written notice of withdrawal of a portion of such Holder's Securities
          previously submitted for purchase pursuant to a Purchase Notice, the
          portion that remains subject to the Purchase Notice), fails to
          indicate such Holder's choice with respect to the election set forth
          in clause (D) of Section 1108(a)(1), such Holder shall be deemed to
          have elected to receive Cash in respect of the entire Purchase Price
          for all Securities subject to such Purchase Notice in the
          circumstances set forth in such clause (D).

                    The Company shall purchase from the Holder thereof, pursuant
          to this Section 1108, a portion of a Security if the Principal Amount
          of such portion is $1,000 or an integral multiple of $1,000.
          Provisions of this Indenture that apply to the purchase of all of a
          Security also apply to the purchase of such portion of such Security.

                    Any purchase by the Company contemplated pursuant to the
          provisions of this Section 1108 shall be consummated by the delivery
          of the consideration to be received by the Holder promptly following
          the later of the Purchase Date and the time of delivery of the
          Security.

                    Notwithstanding anything herein to the contrary, any Holder
          delivering to the Paying Agent the Purchase Notice contemplated by
          this Section 1108(a) shall have the right at any time prior to the
          close of business on the Purchase Date to withdraw such Purchase
          Notice by delivery of a written notice of withdrawal to the Paying
          Agent in accordance with Section 1110.

                                       18
<PAGE>

                    The Paying Agent shall promptly notify the Company of the
          receipt by it of any Purchase Notice or written notice of withdrawal
          thereof.

                    (b) Company's Right to Elect Manner of Payment of Purchase
          Price. The Company may elect with respect to any Purchase Date to pay
          the Purchase Price in respect of the Securities to be purchased
          pursuant to Section 1108(a) as of such Purchase Date, in U.S. legal
          tender ("Cash") or Common Stock, or in any combination of Cash and
          Common Stock, subject to the conditions set forth in Sections 1108(c)
          and (d). The Company shall designate, in the Company Notice delivered
          pursuant to Section 1108(e), whether the Company will purchase the
          Securities for Cash or Common Stock, or, if a combination thereof, the
          percentages of the Purchase Price of Securities which it will pay in
          Cash and in Common Stock; provided that the Company will pay Cash for
          fractional interests in shares of Common Stock. For purposes of
          determining the existence of potential fractional interests, all
          Securities subject to purchase by the Company held by a Holder shall
          be considered together (no matter how many separate certificates are
          to be presented). Each Holder whose Securities are purchased pursuant
          to this Section 1108 shall receive the same percentage of Cash and
          Common Stock in payment of the Purchase Price for such Securities,
          except (i) as provided in Section 1108(d) with regard to the payment
          of Cash in lieu of fractional interests in Common Stock and (ii) in
          the event that the Company is unable to purchase the Securities of a
          Holder or Holders for Common Stock because any necessary
          qualifications or registrations of the Common Stock under applicable
          federal or state securities laws cannot be obtained, the Company may
          purchase the Securities of such Holder or Holders for Cash. The
          Company may not change its election with respect to the consideration
          (or components or percentages of components thereof) to be paid once
          the Company has given its Company Notice to Holders except pursuant to
          this Section 1108(b) or Section 1108(d).

                    At least two Business Days before the Company Notice Date
          (as defined in Section 1108(c)), the Company shall deliver an
          officers' Certificate to the Trustee specifying:

                    (i) the manner of payment selected by the Company,

                    (ii) the information required by Section 1108(e),

                                       19
<PAGE>

                    (iii)  if the Company elects to pay the Purchase Price, or a
          specified percentage thereof, in Common Stock, that the conditions to
          such manner of payment set forth in Section 1108(d) have been or will
          be complied with, and

                    (iv)   whether the Company desires the Trustee to give the
          Company Notice required by Section 1108(e).

                    (c) Purchase with Cash. At the option of the Company, the
          Purchase Price of Securities in respect of which a Purchase Notice
          pursuant to Section 1108(a) has been given, or a specified percentage
          thereof, may be paid by the Company with Cash equal to the aggregate
          Purchase Price, or such specified percentage thereof, as the case may
          be, of such Securities. If the Company elects to purchase Securities
          with Cash, a Company Notice as provided in Section 1108(e) shall be
          sent to Holders (and to Beneficial Owners as required by applicable
          law) not less than 20 Business Days prior to the Purchase Date (the
          "Company Notice Date").

                    (d) Payment by Issuance of Common Stock. At the option of
          the Company, the Purchase Price of Securities in respect of which a
          Purchase Notice pursuant to Section 1108(a) has been given, or a
          specified percentage thereof, may be paid by the Company by the
          issuance of a number of shares of Common Stock equal to the quotient
          obtained by dividing (i) the amount of Cash to which the Holders would
          have been entitled had the Company elected to pay all or such
          specified percentage, as the case may be, of the Purchase Price of
          such Securities in Cash by (ii) the Market Price of a share of Common
          Stock, subject to the next succeeding paragraph.

                    The Company will not issue a fractional share of Common
          Stock in payment of the Purchase Price. Instead the Company will pay
          Cash for the current market value of the fractional share. The current
          market value of a fraction of a share shall be determined by
          multiplying the Market Price by such fraction and rounding the product
          to the nearest whole cent. It is understood that if a Holder elects to
          have more than one Security purchased, the number of shares of Common
          Stock shall be based on the aggregate amount of Securities to be
          purchased.

                    If the Company elects to purchase the Securities by the
          issuance of shares of Common Stock, a Company Notice as provided in
          Section 1108(e) shall be sent to the Holders (and to Beneficial Owners
          as required by applicable law) not later than the Company Notice Date.

                                       20
<PAGE>

                    The Company's right to exercise its election to purchase the
          Securities pursuant to Section 1108 through the issuance of shares of
          Common Stock shall be conditioned upon:

                    (i)    the Company having given timely Company Notice of
          election to purchase all or a specified percentage of the Securities
          with Common Stock as provided herein;

                    (ii)   the registration of the shares of Common Stock to be
          issued in respect of the payment of the specified percentage of the
          Purchase Price under the Securities Act or the Exchange Act, if
          required; unless the shares of Common Stock so issued can be freely
          resold by the Holder (unless such Holder is the Company or an
          Affiliate of the Company) receiving such shares without registration
          under the Securities Act;

                    (iii)  any necessary qualification or registration under
          applicable state securities laws or the availability of an exemption
          from such qualification and registration; and

                    (iv)   the receipt by the Trustee of an officers'
          Certificate and an Opinion of Counsel each stating that (A) the terms
          of the issuance of the Common Stock are in conformity with this
          Indenture and (B) the shares of Common Stock to be issued by the
          Company in payment of the specified percentage of the Purchase Price
          in respect of Securities have been duly authorized and, when issued
          and delivered pursuant to the terms of this Indenture in payment of
          the specified percentage of the Purchase Price in respect of
          Securities, will be validly issued, fully paid and nonassessable, and,
          in the case of such officers' Certificate, stating that conditions
          (i), (ii) and (iii) above have been satisfied and, in the case of such
          Opinion of Counsel, stating that conditions (ii) and (iii) above have
          been satisfied.

                    Such officers' Certificate shall also set forth the number
          of shares of Common Stock to be issued for each $1,000 Principal
          Amount of Securities and the Sale Price of a share of Common Stock on
          each Trading Day during the period during which the Market Price is
          calculated and ending on the Purchase Date. If such conditions are not
          satisfied with respect to a Holder or Holders prior to or on the
          Purchase Date and the Company elected to purchase the Securities to be
          purchased as of such Purchase Date pursuant to this Section 1108
          through the issuance of shares of Common Stock, the Company shall pay
          the entire Purchase Price in respect of such Securities of such Holder
          or Holders in Cash.

                                       21
<PAGE>

                    The "Market Price" means the average of the Sale Prices of
          the Common Stock for the five Trading Day period ending on the third
          Business Day prior to the applicable Purchase Date (if the third
          Business Day prior to the applicable Purchase Date is a Trading Day
          or, if it is not a Trading Day, the five Trading Days ending on the
          last Trading Day prior to the third Business Day), appropriately
          adjusted to take into account the occurrence, during the period
          commencing on the first of such Trading Days during such five Trading
          Day period and ending on such Purchase Date, of any event described in
          Section 1407, 1408 or 1409; subject, however, to the conditions set
          forth in Sections 1410 and 1411.

                    The "Sale Price" of the Common Stock on any date means the
          closing per share sale price (or if no closing sale price is reported
          the average of the bid and ask prices or, if more than one, in either
          case, the average of the average bid and average ask prices) on such
          date as reported on the New York Stock Exchange or, if the Common
          Stock is not quoted on the New York Stock Exchange, on The NASDAQ
          National Market, or if the Common Stock is not listed on The NASDAQ
          National Market, on the principal other national or regional
          securities exchange on which the Common Stock is then listed or, if
          the Common Stock is not listed on a national or regional securities
          exchange, on the principal other market on which the Common Stock is
          then traded.

                    (e) Notice of Election. Company's notices of election to
          purchase with Cash or Common Stock, or any combination thereof, shall
          be sent to the Holders (and to Beneficial Owners as required by
          applicable law) in the manner provided in Section 107 at the time
          specified in Section 1108(c) or (d), as applicable (each, a "Company
          Notice"). Such Company Notices shall state the manner of payment
          elected and shall contain the following information:

                    In the event the Company has elected to pay a Purchase Price
          (or a specified percentage thereof) with Common Stock, the Company
          Notice shall:

                    (1) state that each Holder will receive Common Stock with a
          Market Price determined as of a specified date prior to the Purchase
          Date equal to such specified percentage of the Purchase Price of the
          Securities held by such Holder (except any Cash amount to be paid in
          lieu of fractional shares); and

                    (2) set forth the method by which the Company is required to
          calculate the Market Price and state that because the

                                       22
<PAGE>

          Market Price of Common Stock will be determined prior to the Purchase
          Date, the Holders will bear the market risk with respect to the value
          of the Common Stock to be received from the date such Market Price is
          determined to the Purchase Date.

                    In any case, each Company Notice shall include a form of
          Purchase Notice to be completed by a Holder and shall state:

                    (i)    the Purchase Price and Conversion Rate;

                    (ii)   the name and address of the Paying Agent and the
          Conversion Agent;

                    (iii)  that Securities as to which a Purchase Notice has
          been given may be converted only if the applicable Purchase Notice has
          been withdrawn in accordance with the terms of this Indenture;

                    (iv)   that Securities must be surrendered to the Paying
          Agent to collect payment;

                    (v)    that the Purchase Price for any Security as to which
          a Purchase Notice has been given and not withdrawn will be paid
          promptly following the later of the Purchase Date and the time of
          surrender of such Security as described in (iv);

                    (vi)   the procedures the Holder must follow under this
          Section 1108;

                    (vii)  briefly, the conversion rights of the Securities; and

                    (viii) the procedures for withdrawing a Purchase Notice
          (including, without limitation, for a conditional withdrawal pursuant
          to the terms of Section 1108(a)(1)(D) or Section 1110).

                    At the Company's request, the Trustee shall give the Company
          Notice in the Company's name and at the Company's expense; provided,
          however, that, in all cases, the text of the Company Notice shall be
          prepared by the Company.

                    (f) Covenants of the Company. All shares of Common Stock
          delivered upon conversion or purchase of the Securities shall be newly
          issued shares or treasury shares, shall be fully paid and
          nonassessable and shall be free from preemptive rights and free of any
          lien or adverse claim.

                                       23
<PAGE>

                    The Company shall use its best efforts to list or cause to
          have quoted all such shares of Common Stock on each United States
          national or regional securities exchange on which the Common Stock is
          then quoted or is then listed or if the Common Stock is not then
          listed on a national or regional securities exchange, on the principal
          market on which the Common Stock is then traded.  Upon determination
          of the actual number of shares of Common Stock to be delivered
          pursuant to this Section 1108, the Company shall notify the securities
          exchange or quotation systems on which the Common Stock is then listed
          or quoted and disseminate the number of shares of Common Stock to be
          issued on the Company's website or through an alternative public
          medium.

                    (g) Procedure upon Purchase. On the Business Day following
          the Purchase Date, the Company shall deposit with the Paying Agent (A)
          Cash (in respect of a Cash purchase under Section 1108(c) or for
          fractional interests, as applicable), or (B) shares of Common Stock,
          or a combination of (A) and (B), as applicable, sufficient to pay the
          aggregate Purchase Price in respect of the Securities to be purchased
          pursuant to this Section 1108. As soon as practicable after the
          Purchase Date, the Company shall deliver to each Holder entitled to
          receive Common Stock, through the Paying Agent, a certificate for the
          number of full shares of Common Stock, as applicable, issuable in
          payment of such Purchase Price and Cash in lieu of any fractional
          interests. The Person in whose name the certificate for Common Stock
          is registered shall be treated as a holder of record following the
          Purchase Date. Subject to Section 1108(d), no payment or adjustment
          will be made for dividends on the Common Stock the record date for
          which occurred on or prior to the Purchase Date.

                    (h) Taxes. If a Holder of a Security is paid in Common
          Stock, the Company shall pay any documentary, stamp or similar issue
          or transfer tax due on such issue of shares of Common Stock. However,
          the Holder shall pay any such tax which is due because the Holder
          requests the shares of Common Stock to be issued in a name other than
          the Holder's name. The Paying Agent may refuse to deliver the
          certificates representing the Common Stock being issued in a name
          other than the Holder's name until the Paying Agent receives a sum
          sufficient to pay any tax which will be due because the shares of
          Common Stock are to be issued in a name other than the Holder's name.
          Nothing herein shall preclude any income tax withholding required by
          law or regulations.

                                       24
<PAGE>

          SECTION 1109.  Repurchase at Option of the Holder Upon a Fundamental
          Change.

                    (a)  A fundamental change (hereinafter a "Fundamental
          Change") shall be deemed to have occurred if any of the following
          occurs after May 16, 2001:

                         (1)  any Fundamental Change Person or Group is or
               becomes the Beneficial Owner of shares of Voting Stock of the
               Company representing 50% or more of the total voting power of all
               outstanding classes of Voting Stock of the Company or has the
               power, directly or indirectly, to elect a majority of the members
               of the Board of Directors of the Company; or

                         (2)  the Company consolidates with, or merges with or
               into, another Fundamental Change Person or the Company sells,
               assigns, conveys, transfers, leases or otherwise disposes of all
               or substantially all of the assets of the Company, or any
               Fundamental Change Person consolidates with, or merges with or
               into, the Company; or

                         (3)  there shall occur the liquidation or dissolution
               of the Company.

                         Notwithstanding the foregoing, a "Fundamental Change"
               will not be deemed to have occurred for purposes of clauses (1)
               or (2) of the immediately preceding paragraph if:

                        (1)  Persons that Beneficially Owned shares of Voting
               Stock of the Company immediately prior to such transaction
               Beneficially Own shares with at least a majority of the total
               voting power of all outstanding classes of Voting Stock of the
               surviving or transferee Person; or

                        (2)  at least 50% of the value of the total
               consideration (as determined by the Company, which determination
               shall be conclusive and binding) to be paid or exchanged in
               connection with the proposed transaction consists of common stock
               of the surviving or transferee Person which is listed (or, upon
               consummation of or immediately following such transaction or
               event, which will be listed) on a United States national
               securities exchange or approved for quotation on The NASDAQ
               National Market or any similar United States system of automated
               dissemination of quotations of securities prices.

                                       25
<PAGE>

                        For purposes of this Section 1109, (i) the term
               "Fundamental Change Person" and "Group" have the meanings given
               the term "person" and "group" under Section 13(d) and 14(d) of
               the Exchange Act or any successor provision to either of the
               foregoing, and the term "Group" includes any group acting for the
               purpose of acquiring, holding or disposing of securities within
               the meaning of Rule 13d-5(b)(1) under the Exchange Act (or any
               successor provision thereto), (ii) a "Beneficial Owner" shall be
               determined in accordance with Rule 13d-3 under the Exchange Act,
               as in effect on May 16, 2001, except that the number of shares of
               Voting Stock of the Company shall be deemed to include, in
               addition to all outstanding shares of Voting Stock of the Company
               and Unissued Shares deemed to be held by the Fundamental Change
               Person or Group with respect to which the Fundamental Change
               determination is being made, all Unissued Shares deemed to be
               held by all other Fundamental Change Persons, and (iii) the terms
               "beneficially owned" and "beneficially own" shall have meanings
               correlative to that of "Beneficial Owner".

                    (b) If a Fundamental Change shall occur at any time prior to
          May 16, 2021, each Holder of Securities shall have the right, at such
          Holder's option, to require the Company to repurchase any or all of
          such Holder's Securities for Cash on the date that is 30 days after
          the date of the Company's notice of such Fundamental Change (the
          "Fundamental Change Purchase Date") (or if such date is not a Business
          Day, the next succeeding Business Day). The Securities will be
          redeemable in integral multiples of $1,000 of Principal Amount. The
          Company shall purchase such Securities at a price (the "Fundamental
          Change Purchase Price") equal to the Issue Price plus accrued Original
          Issue Discount up to and including the Fundamental Change Purchase
          Date (or, if the Securities are converted to interest-bearing
          debentures following a Tax Event pursuant to Section 1406 and
          paragraph 6(b) of the Securities, a price equal to the Restated
          Principal Amount plus accrued and unpaid interest from the date the
          Company exercised its right to convert the Securities or the date to
          which interest has been paid, whichever is later, up to and including
          the Fundamental Change Purchase Date). Payment for Securities
          surrendered for purchase (and not withdrawn) prior to the expiration
          of the 30-day period referenced in the first sentence of this
          subsection (a) shall be made promptly following the Fundamental Change
          Purchase Date. No Securities may be redeemed at the option of the
          Holders as a result of a Fundamental Change if there has occurred and
          is continuing an Event of Default

                                       26
<PAGE>

          (other than a default in the payment of the Fundamental Change
          Purchase Price with respect to such Securities).

                    (c) The Company, or at its request (which must be received
          by the Trustee at least three Business Days prior to the date the
          Trustee is requested to give such notice as described below) the
          Trustee in the name of and at the expense of the Company, shall mail
          to the Trustee and all Holders of record of the Securities a notice (a
          "Fundamental Change Purchase Notice") of the occurrence of a
          Fundamental Change and of the redemption right arising as a result
          thereof on or before the tenth day after the occurrence of such
          Fundamental Change.

                    (d) For a Security to be so redeemed at the option of the
          Holder, the Paying Agent must receive such Security, duly endorsed for
          transfer, with the form entitled "Option to Elect Repurchase Upon a
          Fundamental Change" on the reverse thereof duly completed, on or
          before the 30th day after the date of the Fundamental Change Purchase
          Notice (or if such 30th day is not a Business Day, the next succeeding
          Business Day).

          SECTION 1110.  Effect of Purchase Notice or Fundamental Change
          Purchase Notice.

                    Upon receipt by the Company of the Purchase Notice or
          Fundamental Change Purchase Notice specified in Section 1108(a) or
          Section 1109(b), as applicable, the Holder of the Security in respect
          of which such Purchase Notice or Fundamental Change Purchase Notice,
          as the case may be, was given shall (unless such Purchase Notice or
          Fundamental Change Purchase Notice is withdrawn as specified in the
          following two paragraphs) thereafter be entitled to receive solely the
          Purchase Price or Fundamental Change Purchase Price, as the case may
          be, with respect to such Security. Such Purchase Price or Fundamental
          Change Purchase Price shall be paid to such Holder promptly following
          the later of (x) the Purchase Date or the Fundamental Change Purchase
          Date, as the case may be, with respect to such Security (provided the
          conditions in Section 1108(a) or Section 1109(c), as applicable, have
          been satisfied) and (y) the time of delivery of such Security to the
          Paying Agent by the Holder thereof in the manner required by Section
          1108(a) or Section 1109(c), as applicable. Securities in respect of
          which a Purchase Notice or Fundamental Change Purchase Notice, as the
          case may be, has been given by the Holder thereof may not be converted
          for shares of Common Stock on or after the date of the delivery of
          such Purchase Notice (or Fundamental Change Purchase Notice, as the
          case may be), unless such Purchase Notice (or Fundamental

                                       27
<PAGE>

          Change Purchase Notice, as the case may be) has first been validly
          withdrawn as specified in the following two paragraphs.

                    A Purchase Notice or Fundamental Change Purchase Notice, as
          the case may be, may be withdrawn by means of a written notice of
          withdrawal delivered to the office of the Paying Agent at any time
          prior to the close of business on the Purchase Date or the day prior
          to the Fundamental Change Purchase Date, as the case may be, to which
          it relates specifying:

                    (1) if certificated Securities have been issued, the
          certificate number of the Security in respect of which such notice of
          withdrawal is being submitted,

                    (2) the Principal Amount of the Security with respect to
          which such notice of withdrawal is being submitted, and

                    (3) the Principal Amount, if any, of such Security which
          remains subject to the original Purchase Notice or Fundamental Change
          Purchase Notice, as the case may be, and which has been or will be
          delivered for purchase or redemption by the Company.

                    A written notice of withdrawal of a Purchase Notice may be
          in the form of (i) a conditional withdrawal contained in a Purchase
          Notice pursuant to the terms of Section 1108(a)(1)(D) or (ii) a
          conditional withdrawal containing the information set forth in Section
          1108(a)(1)(D) and the preceding paragraph and contained in a written
          notice of withdrawal delivered to the Paying Agent as set forth in the
          preceding paragraph.

                    There shall be no purchase of any Securities pursuant to
          Section 1108 (other than through the issuance of Common Stock in
          payment of the Purchase Price, including Cash in lieu of any
          fractional shares) or redemption pursuant to Section 1109 if there has
          occurred (prior to, on or after, as the case may be, the giving, by
          the Holders of such Securities, of the required Purchase Notice or
          Fundamental Change Purchase Notice, as the case may be) and is
          continuing an Event of Default (other than a default in the payment of
          the Purchase Price or Fundamental Change Purchase Price, as the case
          may be, with respect to such Securities).

          SECTION 1111.  Deposit of Purchase Price or Fundamental Change
          Purchase Price.

                    On or before the Business Day following a Purchase Date or a
          Fundamental Change Purchase Date, as the case may be,

                                       28
<PAGE>

          the Company shall deposit with the Trustee or with the Paying Agent
          (or, if the Company or an Affiliate of the Company is acting as the
          Paying Agent, shall segregate and hold in trust as provided in Section
          1003) an amount of money and/or securities, if permitted hereunder,
          sufficient to pay the aggregate Purchase Price or Fundamental Change
          Purchase Price, as the case may be, of all the Securities or portions
          thereof which are to be purchased as of such Purchase Date or
          Fundamental Change Purchase Date, as the case may be.

          SECTION 1112.  Securities Purchased in Part.

                    Any Security that is to be purchased or redeemed only in
          part shall be surrendered at the office of the Paying Agent (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 such 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 portion of the
          Principal Amount of the Security so surrendered which is not purchased
          or redeemed.

          SECTION 1113.  Covenant To Comply With Securities Laws Upon Purchase
          of Securities.

                    In connection with any purchase or redemption of Securities
          under Section 1108 or 1109 hereof, the Company shall (i) comply with
          Rule 13e-4 (which term, as used herein, includes any successor
          provision thereto) under the Exchange Act, if applicable, (ii) file
          the related Schedule TO (or any successor schedule, form or report)
          under the Exchange Act, if applicable, and (iii) otherwise comply with
          all Federal and state securities laws so as to permit the rights and
          obligations under Section 1108 and 1109 to be exercised in the time
          and in the manner specified in Section 1108 and 1109.

          SECTION 1114.  Repayment to the Company.

                    The Trustee and the Paying Agent shall return to the Company
          any Cash or shares of Common Stock (in the case of the Purchase Price)
          that remains unclaimed as provided in paragraph 14 of the Securities,
          together with interest or dividends, if any, thereon, held by them for
          the payment of a Purchase Price or Fundamental Change Purchase Price,
          as the case may be; provided,

                                       29
<PAGE>

          however, that to the extent that the aggregate amount of Cash or
          shares of Common Stock deposited by the Company pursuant to Section
          1111 exceeds the aggregate Purchase Price or Fundamental Change
          Purchase Price, as the case may be, of the Securities or portions
          thereof which the Company is obligated to purchase as of the Purchase
          Date or Fundamental Change Purchase Date, as the case may be, then
          promptly after the Business Day following the Purchase Date or
          Fundamental Change Purchase Date, as the case may be, the Trustee and
          the Paying Agent shall return any such excess to the Company together
          with interest or dividends, if any, thereon.

          SECTION 1115.  Modification to Fundamental Change Definitions.

                    In the case of a reclassification, change, consolidation,
          merger, combination, sale or conveyance to which Section 1415 applies,
          in which the Common Stock of the Company is changed or exchanged as a
          result into the right to receive stock, securities or other property
          or assets (including Cash), which includes shares of common stock of
          another person that are, or upon issuance will be, traded on a United
          States national securities exchange or approved for trading on an
          established automated over-the-counter trading market in the United
          States and such shares of common stock constitute at the time such
          change or exchange becomes effective in excess of 50% of the aggregate
          fair market value of such stock, securities or other property or
          assets (including Cash) into which the Common Stock of the Company is
          or is to be changed or exchanged for (as determined by the Company,
          which determination shall be conclusive and binding), then the person
          formed by such consolidation or resulting from such merger or which
          acquires such assets, as the case may be, shall execute and deliver to
          the Trustee a supplemental indenture (accompanied by an Opinion of
          Counsel that such supplemental indenture complies with the Trust
          Indenture Act as in force at the date of execution of such
          supplemental indenture) modifying the provisions of this Indenture
          relating to the right of holders of the Securities to cause the
          Company to repurchase the Securities in the event of a Fundamental
          Change, including, without limitation, the applicable provisions of
          this Article Eleven and the definitions of Common Stock and
          Fundamental Change, as appropriate, as determined in good faith by the
          Company (which determination shall be conclusive and binding), to make
          such provisions apply to such other person if different from the
          Company and the common stock issued thereby (in lieu of the Company
          and the Common Stock of the Company).

                                       30
<PAGE>

SECTION 213.  Conversion.

          The following is hereby added to the Indenture immediately following
Article Thirteen, as a new Article Fourteen, with respect to the Debentures
only:

                                ARTICLE FOURTEEN


                                   CONVERSION

          SECTION 1401.  Conversion Privilege.

                    A Holder of a Security may convert such Security for Common
          Stock at any time during the period stated in paragraph 9 of the
          Securities. The number of shares of Common Stock issuable upon
          conversion of a Security per $1,000 of Principal Amount thereof (the
          "Conversion Rate") shall be that set forth in paragraph 9 in the
          Securities, subject to adjustment as herein set forth.

                    A Holder may convert a portion of the Principal Amount of a
          Security if the portion is $1,000 or an integral multiple of $1,000.
          Provisions of this Indenture that apply to conversion of all of a
          Security also apply to conversion of a portion of a Security.

          SECTION 1402.  Conversion Procedure.

                    To convert a Security, a Holder must satisfy the
          requirements in paragraph 9 of the Securities. The date on which the
          Holder of Securities satisfies all those requirements is the
          conversion date (the "Conversion Date"). As soon as practicable after
          the Conversion Date the Company shall deliver to the Holder, through
          the Conversion Agent, a certificate for the number of full shares of
          Common Stock issuable upon the conversion and Cash in lieu of any
          fractional share determined pursuant to Section 1403. The Person in
          whose name the certificate is registered shall be treated as the
          stockholder of record on and after the Conversion Date; provided,
          however, that no surrender of a Security on any date when the stock
          transfer books of the Company shall be closed shall be effective to
          constitute the Person or Persons entitled to receive the shares of
          Common Stock upon such conversion as the record holder or holders of
          such shares of Common Stock on such date, but such surrender shall be
          effective to constitute the Person or Persons entitled to receive such
          shares of Common Stock as the record holder or holders thereof for all
          purposes at the close of business on the next succeeding day on which
          such stock transfer books are open; such conversion shall be at the
          Conversion Rate in

                                       31
<PAGE>

          effect on the date that such Security shall have been surrendered for
          conversion, as if the stock transfer books of the Company had not been
          closed. Upon conversion of a Security, such Person shall no longer be
          a Holder of such Security.

                    No payment on the Securities or adjustment of the Conversion
          Rate will be made for dividends on or other distributions with respect
          to any Common Stock except as provided in this Article Fourteen. On
          conversion of a Security, that portion of accrued Original Issue
          Discount attributable to the period from the Issue Date of the
          Security to the Conversion Date with respect to the converted Security
          shall not be canceled, extinguished or forfeited, but rather shall be
          deemed to be paid in full to the Holder thereof through delivery of
          the Common Stock (together with the Cash payment, if any, in lieu of
          fractional shares) in exchange for the Security being converted
          pursuant to the provisions hereof.

                    If a Holder converts more than one Security at the same
          time, the number of shares of Common Stock issuable upon the
          conversion shall be based on the total Principal Amount of the
          Securities converted.

                    Upon surrender of a Security that is converted in part, the
          Company shall execute, and the Trustee shall authenticate and deliver
          to the Holder, a new Security in an authorized denomination equal in
          Principal Amount to the unconverted portion of the Security
          surrendered.

                    If the last day on which a Security may be converted is not
          a Business Day in a place where a Conversion Agent is located, the
          Security may be surrendered to that Conversion Agent on the next
          succeeding day that it is a Business Day.

          SECTION 1403.  Fractional Shares.

                    The Company will not issue a fractional share of Common
          Stock upon conversion of a Security. Instead the Company will deliver
          Cash for the current market value of the fractional share. The current
          market value of a fractional share shall be determined to the nearest
          1/10,000th of a share by multiplying the last reported sale price
          (determined as set forth in the definition of Market Price) on the
          last Trading Day prior to the Conversion Date of a full share by the
          fractional amount and rounding the product to the nearest whole cent.

                                       32
<PAGE>

          SECTION 1404.  Taxes on Conversion.

                    If a Holder converts a Security, the Company shall pay any
          documentary, stamp or similar issue or transfer tax due on the issue
          of shares of Common Stock upon the conversion. However, the Holder
          shall pay any such tax which is due because the Holder requests the
          shares to be issued in a name other than the Holder's name. The
          Conversion Agent may refuse to deliver the certificates representing
          the Common Stock being issued in a name other than the Holder's name
          until the Conversion Agent receives a sum sufficient to pay any tax
          which will be due because the shares are to be issued in a name other
          than the Holder's name. Nothing herein shall preclude any tax
          withholding required by law or regulations.

          SECTION 1405.  Company to Provide Stock.

                    The Company shall, prior to issuance of any Securities
          hereunder, and from time to time as may be necessary, reserve out of
          its authorized but unissued Common Stock a sufficient number of shares
          of Common Stock to permit the conversion of the Securities.

                    All shares of Common Stock delivered upon conversion of the
          Securities shall be newly issued shares or treasury shares, shall be
          duly and validly issued and fully paid and nonassessable and shall be
          free from preemptive rights and free of any lien or adverse claim.

                    The Company covenants that if any shares of Common Stock to
          be provided for the purpose of conversion of Securities hereunder
          require registration with or approval of any governmental authority
          under any federal or state law before such shares may be validly
          issued upon conversion, the Company will in good faith and as
          expeditiously as possible endeavor to secure such registration or
          approval, as the case may be.

                    The Company further covenants that if at any time the Common
          Stock shall be quoted on The NASDAQ National Market or any other
          automated quotation system or listed on the New York Stock Exchange or
          any other national or regional securities exchange, the Company will,
          if permitted by the rules of such automated quotation system or
          exchange, list and keep listed, so long as the Common Stock shall be
          so listed on such automated quotation system or exchange, all shares
          of Common Stock issuable upon conversion of the Securities; provided,
          however, that if the rules of such automated quotation system or
          exchange permit

                                       33
<PAGE>

          the Company to defer the listing of such Common Stock until the first
          conversion of the Securities into Common Stock in accordance with the
          provisions of this Indenture, the Company covenants to list such
          Common Stock issuable upon conversion of the Securities in accordance
          with the requirements of such automated quotation system or exchange
          at such time.

          SECTION 1406.  Conversion to Semiannual Coupon Debentures Upon A Tax
          Event.

                    (a) If at any time after the date (the "Tax Event Date") of
          the occurrence of a Tax Event the Company exercises its option (the
          date of such exercise, the "Option Exercise Date") to pay interest in
          lieu of Original Issue Discount, interest in lieu of future Original
          Issue Discount shall accrue at the rate of 1.25% per annum on the
          Principal Amount per Security (the "Restated Principal Amount") equal
          to the Issue Price plus Original Issue Discount accrued through the
          Option Exercise Date (as calculated by the Company and set forth in an
          officer's Certificate delivered to the Trustee) and shall be payable
          semiannually on May 15 and November 15 of each year (each an "Interest
          Payment Date") to holders of record of the Securities at the close of
          business on the May 1 and November 1, respectively (each a "Regular
          Record Date"), immediately proceeding such Interest Payment Date.
          Interest will be computed on the basis of a 360-day year comprised of
          twelve 30-day months and will accrue from the most recent date to
          which interest has been paid or, if no interest has been paid, from
          the Option Exercise Date. Interest on any Security that is payable on
          any Interest Payment Date shall be paid to the Person in whose name
          that Security is registered at the close of business on the Regular
          Record Date.

                    (b) Within 15 days after the Option Exercise Date, the
          Company shall mail a written notice of the exercise of its option
          pursuant to Section 1406(a) by first class mail to the Trustee and the
          Holders of the Securities. From and after the Option Exercise Date,
          (i) the Company shall be obligated to pay at Stated Maturity, in lieu
          of the Principal Amount of a Security, the Restated Principal Amount
          thereof and (ii) "Issue Price and accrued Original Issue Discount,"
          "Issue Price plus Original Issue Discount" or similar words, as used
          herein, shall mean Restated Principal Amount plus accrued and unpaid
          interest with respect to any Security. Securities authenticated and
          delivered after the Option Exercise Date may, and shall if required by
          the Trustee, bear a notation in a form approved by the Trustee as to
          the conversion of the Securities to semiannual coupon debentures.

                                       34
<PAGE>

                    (c) Interest on any Security that 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 is registered
          at the close of business on the Regular Record Date for such interest
          at the office or agency of the Company maintained for such purpose.
          Each installment of interest on any Security shall be paid in same-day
          funds by transfer to an account maintained by the payee located inside
          the United States. In the case of a permanent Global Security,
          interest payable on any Interest Payment Date will be paid to the
          Depositary, with respect to that portion of such permanent Global
          Security, held for its account by Cede & Co. or another nominee for
          the Depositary for the purpose of permitting such party to credit the
          interest received by it in respect of such permanent Security in
          global form to the accounts of the Beneficial Owners thereof.

                    (d) The provisions of Section 307 of the Indenture shall
          apply to the Debentures from and after the Option Exercise Date.

                    (e) In the event that the Company exercises its option
          pursuant to Section 1406(a) following a Tax Event, any Security or
          portion thereof surrendered for conversion after the first Interest
          Payment Date with respect to the Securities must be accompanied by a
          payment, in funds acceptable to the Company, equal to the sum of all
          cash interest paid on the Security or portion thereof being converted,
          plus (in the case of a Security or portion thereof being surrendered
          for conversion during the period from the close of business on the
          Regular Record Date to the opening of business on the immediately
          following Interest Payment Date unless such Security or portion
          thereof being converted shall have been called for redemption on a
          date in such period) the amount of interest otherwise payable on such
          Interest Payment Date on the amount of principal being converted.

                    Interest on any Security that is payable on any Interest
          Payment Date shall be paid to the Person in whose name that Security
          is registered at the close of business on the Regular Record Date.

          SECTION 1407.  Adjustment For Change In Capital Stock.

                    In case the Company shall (i) pay a dividend, or make a
          distribution, in shares of its Common Stock, on its Common Stock, (ii)
          subdivide its outstanding Common Stock into a greater number of
          shares, or (iii) combine its outstanding Common Stock into a smaller
          number of shares, the Conversion

                                       35
<PAGE>

          Rate in effect immediately prior thereto shall be adjusted so that the
          holder of any Security thereafter surrendered for conversion shall be
          entitled to receive the number of shares of Common Stock which such
          Holder would have owned or have been entitled to receive after the
          occurrence of any of the events described above had such Security been
          converted immediately prior to the occurrence of such event. If any
          dividend or distribution of the type described in clause (i) above is
          not so paid or made, the Conversion Rate shall again be adjusted to
          the Conversion Rate which would then be in effect if such dividend as
          distribution had not been declared. An adjustment made pursuant to
          this Section 1407 shall become effective immediately after the record
          date in the case of a dividend and shall become effective immediately
          after the effective date in the case of a subdivision or combination.

          SECTION 1408.  Adjustment For Rights Issue.

                    In case the Company shall issue rights or warrants to all
          holders of its Common Stock entitling them (for a period expiring
          within 45 days after the record date mentioned below) to subscribe for
          or purchase Common Stock at a price per share less than the Market
          Price per share of Common Stock at the record date for the
          determination of stockholders entitled to receive such rights or
          warrants, the Conversion Rate in effect immediately prior thereto
          shall be adjusted so that the same shall equal the Conversion Rate
          determined by multiplying the Conversion Rate in effect immediately
          prior to the date of issuance of such rights or warrants by a fraction
          of which the numerator shall be the number of shares of Common Stock
          outstanding on the date of issuance of such rights or warrants plus
          the number of additional shares of Common Stock offered to holders of
          Common Stock for subscription or purchase, and of which the
          denominator shall be the number of shares of Common Stock outstanding
          on the date of issuance of such rights or warrants plus the number of
          shares of Common Stock which the aggregate offering price of the total
          number of shares so offered would purchase at such Market Price. Such
          adjustment shall be made successively whenever any such rights or
          warrants are issued, and shall become effective immediately after the
          opening of business on the day following the record date for the
          determination of the stockholders entitled to receive such rights or
          warrants. To the extent that shares of Common Stock are not delivered
          after the expiration of such rights or warrants, the Conversion Rate
          shall be readjusted to the Conversion Rate which would then be in
          effect had the adjustments made upon the issuance of such rights or
          warrants been made on the basis of delivery of only the number of
          shares of Common Stock actually delivered. If such rights or warrants
          are

                                       36
<PAGE>

          not so issued, the Conversion Rate shall again be adjusted to be
          the Conversion Rate which would then be in effect if such record date
          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 Market Price of such Common Stock, and
          in determining the aggregate offering price of such shares of Common
          Stock, there shall be taken into account any consideration received by
          the Company for such rights or warrants, the value of such
          consideration, if other than Cash, to be determined by the Board of
          Directors.

          SECTION 1409.  Adjustment For Other Distributions.

                    (a) In case the Company shall distribute to all holders of
          its Common Stock (excluding any distribution in connection with the
          liquidation, dissolution or winding up of the Company, whether
          voluntary or involuntary) any shares of any class of capital stock of
          the Company (other than Common Stock), of evidences of indebtedness of
          the Company or of assets (other than Cash) or rights or warrants to
          subscribe for or purchase any of its securities (excluding those
          referred to in Section 1408 hereof) (any of the foregoing hereinafter
          in this Section 1409(a) called the "Distributed Securities"), then,
          the Conversion Rate shall be adjusted so that the same shall equal the
          Conversion Rate determined by multiplying the Conversion Rate in
          effect immediately prior to the date of such distribution by a
          fraction of which the numerator shall be the Market Price per share of
          the Common Stock on the record date mentioned below, and the
          denominator shall be the Market Price per share of the Common Stock on
          such record date less the fair market value on such record date (as
          determined by the Board of Directors of the Company, whose
          determination shall be conclusive, and described in a certificate
          filed with the Trustee) of the Distributed Securities so distributed
          applicable to one share of Common Stock. Such adjustment shall become
          effective immediately after the record date for the determination of
          stockholders entitled to receive such distribution. Notwithstanding
          the foregoing, in the event that the then fair market value (as so
          determined) of the portion of the Distributed Securities so
          distributed applicable to one share of Common Stock is equal to or
          greater than the Market Price of the Common Stock 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
          the amount of Distributed Securities such Holder would have received
          had such Holder converted each Security immediately prior to such
          record date. In the event that such distribution is not so paid or
          made, the

                                       37
<PAGE>

          Conversion Rate shall again be adjusted to the Conversion Rate which
          would then be in effect if such distribution had not been declared. If
          the Board of Directors determines the fair market value of any
          distribution for purposes of this Section 1409(a) by reference to the
          actual or when issued trading market for any securities, it must in
          doing so consider the prices in such market over the same period used
          in computing the Market Price of the Common Stock.

                    Notwithstanding the foregoing provisions of this Section
          1409(a), no adjustment shall be made thereunder for any distribution
          of Distributed Securities if the Company makes proper provision so
          that each Holder of a Security who converts such Security (or any
          portion thereof) after the record date for such distribution shall be
          entitled to receive upon such conversion, in addition to the shares of
          Common Stock issuable upon such conversion, the amount and kind of
          Distributed Securities that such Holder would have been entitled to
          receive if such Holder had, immediately prior to such record date,
          converted such Security for Common Stock; provided that, with respect
          to any Distributed Securities that are convertible, exchangeable or
          exercisable, the foregoing provision shall only apply to the extent
          (and so long as) the Distributed Securities receivable upon conversion
          of such Security would be convertible, exchangeable or exercisable, as
          applicable, without any loss of rights or privileges for a period of
          at least 60 days following conversion of such Security.

                    (b) In case the Company shall, by dividend or otherwise,
          distribute to all holders of its Common Stock Cash (excluding any
          quarterly Cash dividend on the Common Stock to the extent the
          aggregate Cash dividend per share of Common Stock in any fiscal
          quarter does not exceed the greater of (A) the amount per share of
          Common Stock of the next preceding quarterly Cash dividend on the
          Common Stock to the extent such preceding quarterly dividend did not
          require any adjustment of the Conversion Rate pursuant to this Section
          1409(b) (as adjusted to reflect subdivisions or combinations of the
          Common Stock), and (B) 3.75% of the average of the last reported sales
          price of the Common Stock (determined as provided in the definition of
          Market Price) during the ten Trading Days immediately prior to the
          date of declaration of such dividend, then, in such case, unless the
          Company elects to reserve such Cash for distribution to the holders of
          the Securities upon the conversion of the Securities so that any such
          holder converting Securities will receive upon such conversion in
          addition to the shares of Common Stock to which such holder is
          entitled, the amount of Cash which such holder would have received if
          such holder had, immediately prior to the

                                       38
<PAGE>

          record date for such distribution of Cash, converted its Securities
          for Common Stock, the Conversion Rate shall be increased so that the
          same shall equal the Conversion Rate determined by multiplying the
          Conversion Rate in effect immediately prior to the record date by a
          fraction of which the numerator shall be such Market Price of the
          Common Stock and the denominator shall be the Market Price of the
          Common Stock on the record date less the amount of Cash so distributed
          (and not excluded as provided above) applicable to one share of Common
          Stock, such increase to be effective immediately prior to the opening
          of business on the day following the record date; provided, however,
          that in the event that the portion of the Cash so distributed
          applicable to one share of Common Stock is equal to or greater than
          the Market Price of the Common Stock 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 the amount
          of Cash such Holder would have received had such Holder converted each
          Security on the record date. If such dividend or distribution is not
          so paid or made, the Conversion Rate shall again be adjusted to be the
          Conversion Rate which would then be in effect if such dividend or
          distribution had not been declared. If any adjustment is required to
          be made as set forth in this Section 1409(b) as a result of a
          distribution that is a quarterly dividend, such adjustment shall be
          based upon the amount by which such distribution exceeds the amount of
          the quarterly Cash dividend permitted to be excluded pursuant hereto.
          If an adjustment is required to be made as set forth in this Section
          1409(b) above as a result of a distribution that is not a quarterly
          dividend, such adjustment shall be based upon the full amount of the
          distribution.

                    (c) In case a tender or exchange offer made by the Company
          or any Subsidiary of the Company for all or any portion of the Common
          Stock shall expire and such tender or exchange offer shall involve the
          payment by the Company or such Subsidiary of consideration per share
          of Common Stock having a fair market value (as determined by the Board
          of Directors, whose determination shall be conclusive, and described
          in a resolution of such Board of Directors at the last time (the
          "Expiration Time") tenders or exchanges may be made pursuant to such
          tender or exchange offer (as it shall have been amended)) that exceeds
          the Market Price of the Common Stock on the Trading Day next
          succeeding the Expiration Time, the Conversion Rate shall be increased
          so that the same shall equal the Conversion Rate determined by
          multiplying the Conversion Rate in effect immediately prior to the
          Expiration Time by a fraction of which the numerator shall be the sum
          of (x) the fair market value (determined as aforesaid) of the
          aggregate consideration payable to

                                       39
<PAGE>

          holders of Common Stock based on the acceptance (up to any maximum
          specified in the terms of the tender or exchange offer) of all shares
          of Common Stock validly tendered or exchanged 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
          Purchased Shares) as of the Expiration Time and the Market Price of
          the Common Stock on the Trading Day next succeeding the Expiration
          Time, and the denominator shall be the number of shares of Common
          Stock outstanding (including any tendered or exchanged shares) as of
          the Expiration Time multiplied by the Market Price of the Common Stock
          on the Trading Day next succeeding the Expiration Time, such increase
          to 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 or
          exchange offer, but the Company is permanently prevented by applicable
          law from effecting any such purchases or all such purchases are
          rescinded, the Conversion Rate shall again be adjusted to be the
          Conversion Rate which would then be effect if such tender or exchange
          offer had not been made.

                    (d) In case of a tender or exchange offer by a Person other
          than the Company or any Subsidiary for an amount which increases the
          offeror's ownership of Common Stock to more than 25% of the Common
          Stock outstanding and shall involve the payment by such Person of
          consideration per share of Common Stock having a fair market value (as
          determined by the Board of Directors, whose determination shall be
          conclusive, and described in a resolution of the Board of Directors at
          the last time (the "Tender Expiration Time") tenders or exchanges may
          be made pursuant to such tender or exchange offer (as it shall have
          been amended)) at the Tender Expiration Time that exceeds the Market
          Price of the Common Stock on the Trading Day next succeeding the
          Tender Expiration Time, and in which, as of the Tender Expiration Time
          the Board of Directors is not recommending rejection of the offer, the
          Conversion Rate shall be increased so that the same shall equal the
          Conversion Rate determined by multiplying the Conversion Rate in
          effect immediately prior to the Tender Expiration Time by a fraction
          of which the numerator shall be the sum of (x) the fair market value
          (determined as aforesaid) of the aggregate consideration payable to
          holders of Common Stock based on the acceptance (up to an maximum
          specified in the terms of the tender or exchanged offer) of all shares
          of Common Stock validly tendered or exchanged and not withdrawn as of
          the Tender Expiration Time (the shares deemed so accepted, up to any
          such maximum, being referred to as the "Tender Purchased Shares")

                                       40
<PAGE>

          and (y) the product of the number of shares of Common Stock
          outstanding (less any Tender Purchased Shares) on the Tender
          Expiration Time and the Market Price of the Common Stock on the
          Trading Day next succeeding the Tender Expiration Time and the
          denominator shall be the number of shares of Common Stock outstanding
          (including the Tender Purchased Shares) as of the Tender Expiration
          Time multiplied by the Market Price of the Common Stock on the Trading
          Day next succeeding the Tender Expiration Time, such increase to
          become effective immediately prior to the opening of business on the
          day following the Tender Expiration Time. In the event that such
          Person is obligated to purchase shares pursuant to any such tender or
          exchange offer, but such Person is permanently prevented by applicable
          law from effecting any such purchases or any or all such purchases are
          rescinded, the Conversion Rate shall again be adjusted to be the
          Conversion Rate which would then be in effect if such tender or
          exchange offer had not been made or if the rescinded purchases (if
          less than all) had not been made. Notwithstanding the foregoing, the
          adjustment described in this Section 1409(d) shall not be made if, as
          of the Tender Expiration Time, the offering documents with respect to
          such offer disclose a plan or intention to cause the Company to engage
          in any transaction described in Article Eight.

          SECTION 1410.  When Adjustment May Be Deferred.

                    No adjustment in the Conversion Rate need be made unless the
          adjustment would require an increase or decrease of at least 1% in the
          Conversion Rate. Any adjustments that are made shall be carried
          forward and taken into account any subsequent adjustment.

                    All calculations under this Article Fourteen shall be made
          to the nearest cent or to the nearest 1/10,000th of a share, as the
          case may be.

          SECTION 1411.  When No Adjustment Required.

                    No adjustment need be made for rights to purchase Common
          Stock pursuant to a Company plan for reinvestment of dividends or
          interest.

                    No adjustment need be made for a change in the par value of
          the Common Stock. To the extent the Securities become convertible into
          Cash, assets, property or securities (other than capital stock of the
          Company), no adjustment need be made thereafter as to the cash,
          assets, property or such securities. Interest will not accrue on the
          Cash.

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<PAGE>

          SECTION 1412.  Notice of Adjustment.

                    Whenever the Conversion Rate is adjusted, the Company shall
          promptly mail to Holders a notice of the adjustment. The Company shall
          file with the Trustee and the Conversion Agent such notice. The
          certificate shall, absent manifest error, be conclusive evidence that
          the adjustment is correct. Neither the Trustee nor any Conversion
          Agent shall be under any duty or responsibility with respect to any
          such certificate except to exhibit the same to any Holder desiring
          inspection thereof.

          SECTION 1413.  Voluntary Increase.

                    The Company may make such increases in the Conversion Rate,
          in addition to those required by Sections 1407, 1408 and 1409, 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 may
          from time to time increase the Conversion Rate by any amount for any
          period of time if the period is at least 20 days, the increase is
          irrevocable during the period and the Board of Directors shall have
          made a determination that such increase would be in the best interests
          of the Company, which determination shall be conclusive. Whenever the
          Conversion Rate is so increased, the Company shall mail to Holders and
          file with the Trustee and the Conversion Agent a notice of such
          increase. The Company shall mail such notice at least seven days
          before the date the increased Conversion Rate takes effect. The notice
          shall state the increased Conversion Rate and the period it will be in
          effect.

          SECTION 1414.  Notice of Certain Transactions.

                    If:

                    (1)  the Company makes any distribution or dividend that
          would require an adjustment in the Conversion Rate pursuant to Section
          1407, 1408 or 1409; or

                    (2)  the Company takes any action that would require a
          supplemental indenture pursuant to Section 1415; or

                    (3)  there is a liquidation, dissolution or winding-up of
          the Company;

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<PAGE>

                    then the Company shall mail to Holders and file with the
          Trustee and the Conversion Agent a notice stating the proposed record
          date for a dividend or distribution or the proposed effective date of
          a subdivision, combination, reclassification, consolidation, merger,
          sale, transfer, dissolution, liquidation or winding up. The Company
          shall file and mail the notice at least 15 days before such date.
          Failure to file or mail the notice or any defect in it shall not
          affect the validity of the transaction.

          SECTION 1415.  Effect of Reclassification, Consolidation, Merger or
          Sale.

                    If any of the following events occur, namely (i) any
          reclassification or change of 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 consolidation, merger 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,
          then the Company or the successor or purchasing corporation, as the
          case may be, shall execute with the Trustee a supplemental indenture,
          providing that each Security shall be convertible into the kind and
          amount of shares of stock and other securities or property or assets
          (including Cash) receivable upon such reclassification, change,
          consolidation, merger, combination, sale or conveyance by a holder of
          a number of shares of Common Stock issuable upon conversion of such
          Securities immediately prior to such reclassification, change,
          consolidation, merger, combination, sale or conveyance. 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.

                    The Company shall cause notice of the execution of such
          supplemental indenture to be mailed to each Holder of Securities, at
          such Holder's address appearing on the Security Register provided for
          in Section 305 of this Indenture.

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

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<PAGE>

                    If this Section applies, neither Section 1407, 1408 nor 1409
          applies.

          SECTION 1416.  Company Determination Final.

                    Any determination that the Company or the Board of Directors
          must make pursuant to Section 1403, 1407, 1408, 1409, 1410, 1411, 1415
          or 1418 is conclusive.

          SECTION 1417.  Trustee's Adjustment Disclaimer.

                    The Trustee has no duty to determine when an adjustment
          under this Article Fourteen should be made, how it should be made or
          what it should be. The Trustee has no duty to determine whether a
          supplemental indenture under Section 1415 need be entered into or
          whether any provisions of any supplemental indenture are correct. The
          Trustee shall not be accountable for and makes no representation as to
          the validity or value of any securities or assets issued upon
          conversion of Securities. The Trustee shall not be responsible for the
          Company's failure to comply with this Article Fourteen, and shall not
          be deemed to have knowledge of any adjustment unless and until it
          shall have received a notice of adjustment pursuant to Section 1412.
          Each Conversion Agent shall have the same protection under this
          Section 1417 as the Trustee.

          SECTION 1418.  Simultaneous Adjustments.

                    In the event that this Article Fourteen requires adjustments
          to the Conversion Rate under more than one of Sections 1407, 1408,
          1409(a) or 1409(b), and the record dates for the distributions giving
          rise to such adjustments shall occur on the same date, then such
          adjustments shall be made by applying, first, the provisions of
          Section 1409(a), second, the provisions of Section 1409(b), third the
          provisions of Section 1407 and, fourth, the provisions of Section
          1408.

          SECTION 1419.  Successive Adjustments.

                    After an adjustment to the Conversion Rate under this
          Article Fourteen, any subsequent event requiring an adjustment under
          this Article Fourteen shall cause an adjustment to the Conversion Rate
          as so adjusted.

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<PAGE>

          SECTION 1420.  Rights Issued in Respect of Common Stock Issued Upon
          Conversion.

                    Notwithstanding any other provision hereof, in the event
          that the Company implements a stockholders' rights plan, such rights
          plan shall provide that upon conversion of the Securities the Holders
          will receive, in addition to the Common Stock issuable upon such
          conversion, such rights whether or not such rights have separated from
          the Common Stock at the time of such conversion. In the event that
          provision is made that a Holder of Securities will receive such rights
          upon conversion, whether or not the rights have separated from the
          Common Stock at the time of such conversion, no adjustment shall be
          made to the Conversion Rate pursuant to this Article Fourteen as a
          result of such rights distribution.

                    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 not be deemed distributed for purposes of Section 1409(a) until
          the occurrence of the earliest Trigger Event. In addition, in the
          event of any distribution of rights or warrants, or any Trigger Event
          with respect thereto, that shall have resulted in an adjustment to the
          Conversion Rate under Section 1409(a), (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 Rate 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 any such rights
          or warrants all of which shall have expired without exercise

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<PAGE>

          by any holder thereof, the Conversion Rate shall be readjusted as if
          such issuance had not occurred.

          SECTION 1421.  General Considerations.

                    Whenever successive adjustments to the Conversion Rate are
          called for pursuant to this Article Fourteen, such adjustments shall
          be made to the Market Price or the Conversion Rate adjustment
          provisions of Sections 1407, 1408, 1409 and 1418 as may be necessary
          or appropriate to effectuate the intent of this Article Fourteen and
          to avoid unjust or inequitable results as determined in good faith by
          the Board of Directors.

SECTION 214.  Amendment to Events of Default.

          Clause (2) of Section 501 of the Indenture is amended to read in its
entirety as follows, with respect to the Debentures only:

                    (2) default in the payment of the Principal Amount (or, if
          the Debentures have been converted to interest-bearing Debentures
          pursuant to Section 1406, the Restated Principal Amount), the
          Redemption Price, the Purchase Price or the Fundamental Change
          Purchase Price when the same becomes due and payable at its Stated
          Maturity upon redemption, upon declaration of acceleration, when due
          for repurchase by the Company or otherwise;

                                 ARTICLE THREE


                            MISCELLANEOUS PROVISIONS

SECTION 301.  Ratification of Indenture.

          As supplemented by this Supplemental Indenture, the Indenture is in
all respects ratified and confirmed and the Indenture as so supplemented by this
Supplemental Indenture shall be read, taken and construed as one and the same
instrument.

SECTION 302.  Conflict With Trust Indenture Act.

          If any provision hereof limits, qualifies or conflicts with another
provision hereof which is required to be included in this Supplemental Indenture
by any of the provisions of the Trust Indenture Act, such required provisions
shall control.

SECTION 303.  Integral Part.

          This Supplemental Indenture constitutes an integral part of the
Indenture.



                                       46
<PAGE>

SECTION 304.  General Definitions.

          For all purposes of this Supplemental Indenture:

          (a)  capitalized terms used herein without definition shall have the
meanings specified in the Indenture; and

          (b)  the terms "herein", "hereof", "hereunder" and other words of
similar import refer to this Supplemental Indenture.

SECTION 305.  Effect of Headings.

          The article and section headings herein are included for convenience
only and shall not affect the construction hereof.

SECTION 306.  Counterparts.

          This Supplemental Indenture may be executed in any number of
counterparts, each of which shall be an original; but such counterparts shall
together constitute but one and the same instrument.

SECTION 307.  Severability.

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

SECTION 308.  Benefits of Supplemental Indenture.

          Nothing in this Supplemental Indenture or in the Debentures, express
or implied, shall give to any Person, other than the parties hereto and their
successors hereunder and the Holders, any benefit or any legal or equitable
right, remedy or claim under this Supplemental Indenture.

SECTION 309.  Acceptance of Trusts.

          Bank One Trust Company, National Association, hereby accepts the
trusts in this Supplemental Indenture declared and provided, upon the terms and
conditions herein and in the Indenture set forth.

SECTION 310.  Governing Law.

          This Supplemental Indenture and each Debenture issued hereunder shall
be deemed to be a contract made under the laws of the State of New York, and for
all purposes shall be construed in accordance with the laws of said State.

                                       47
<PAGE>

          IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed, and their respective corporate seals to be
hereunto affixed and attested, all as of the date first above written.


                                 COOPER CAMERON CORPORATION



                                 By:    /s/ MICHAEL C. JENNINGS
                                        ----------------------------------------
                                 Name:  Michael C. Jennings
                                 Title: Vice President and Treasurer


                                 BANK ONE TRUST COMPANY,
                                 NATIONAL ASSOCIATION



                                 By: /s/ JOSEPH MORAND
                                     -------------------------------------------
                                     Joseph Morand
                                     Vice President

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