Document:

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                                                                    EXHIBIT 10.2

                               SEVERANCE AGREEMENT

         THIS AGREEMENT, dated July 17, 2000 is made by and between BAKER HUGHES
INCORPORATED, a Delaware corporation (the "Company"), and Michael E. Wiley (the
"Executive").

         WHEREAS, the Company considers it essential to the best interests of
its stockholders to foster the continued employment of key management personnel;
and

         WHEREAS, the Board recognizes that, as is the case with many publicly
held corporations, the possibility of a Change in Control exists and that such
possibility, and the uncertainty and questions which it may raise among
management, may result in the departure or distraction of management personnel
to the detriment of the Company and its stockholders; and

         WHEREAS, the Board has determined that appropriate steps should be
taken to reinforce and encourage the continued attention and dedication of
members of the Company's management, including the Executive, to their assigned
duties without distraction in the face of potentially disturbing circumstances
arising from the possibility of a Change in Control;

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants herein contained, the Company and the Executive hereby agree as
follows:

         1. Defined Terms. The definitions of capitalized terms used in this
Agreement are provided in the last Section hereof.

         2. Term of Agreement. Subject to the provisions of Section 12.2 hereof,
the Term of this Agreement shall commence on the date of your employment with
the Company (which is expected to be August 14, 2000) and shall continue in
effect through December 31, 2001; provided, however, that commencing on January
1, 2001 and each January 1 thereafter (an

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"Extension Date"), the Term shall automatically be extended for one additional
year (i.e., resulting in a two-year Term on the Extension Date) unless, not
later than September 30 of the year preceding the Extension Date, the Company or
the Executive shall have given notice not to extend the Term; and further
provided, however, that if a Change in Control shall have occurred during the
Term, the Term shall expire no earlier than twenty-four (24) months beyond the
month in which such Change in Control occurred.

         3. Company's Covenants Summarized. In order to induce the Executive to
remain in the employ of the Company and in consideration of the Executive's
covenants set forth in Section 4 hereof, the Company agrees, under the
conditions described herein, to pay the Executive the Severance Payments and the
other payments and benefits described herein. Except as provided in Section 9.1
hereof, no Severance Payments shall be payable under this Agreement unless there
shall have been (or, under the terms of the second sentence of Section 6.1
hereof, there shall be deemed to have been) a termination of the Executive's
employment with the Company following a Change in Control and during the Term.
This Agreement shall not be construed as creating an express or implied contract
of employment and, except as otherwise agreed in writing between the Executive
and the Company, the Executive shall not have any rights to be retained in the
employ of the Company.

         4. The Executive's Covenants. The Executive agrees that, subject to the
terms and conditions of this Agreement, in the event of a Potential Change in
Control during the Term, the Executive will remain in the employ of the Company
until the earliest of (i) a date which is six (6) months from the date of such
Potential Change of Control, (ii) the date of a Change in Control, (iii) the
date of termination by the Executive of the Executive's employment for Good
Reason or by

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reason of death, Disability or Retirement, or (iv) the termination by the
Company of the Executive's employment for any reason.

         5. Compensation Other Than Severance Payments.

         5.1 Following a Change in Control and during the Term, during any
period that the Executive fails to perform the Executive's full-time duties with
the Company as a result of incapacity due to physical or mental illness, the
Company shall pay the Executive's full salary to the Executive at the rate in
effect at the commencement of any such period, together with all compensation
and benefits payable to the Executive under the terms of any compensation or
benefit plan, program or arrangement maintained by the Company during such
period, until the Executive's employment is terminated by the Company for
Disability.

         5.2 If the Executive's employment shall be terminated for any reason
following a Change in Control and during the Term, the Company shall pay the
Executive's full salary to the Executive through the Date of Termination at the
rate in effect immediately prior to the Date of Termination or, if higher, the
rate in effect immediately prior to the first occurrence of an event or
circumstance constituting Good Reason, together with all compensation and
benefits payable to the Executive through the Date of Termination under the
terms of the Company's compensation and benefit plans, programs or arrangements
as in effect immediately prior to the Date of Termination or, if more favorable
to the Executive, as in effect immediately prior to the first occurrence of an
event or circumstance constituting Good Reason.

         5.3 If the Executive's employment shall be terminated for any reason
following a Change in Control and during the Term, the Company shall pay to the
Executive the Executive's normal post-termination compensation and benefits as
such payments become due. Such post-

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termination compensation and benefits shall be determined under, and paid in
accordance with, the Company's retirement, insurance and other compensation or
benefit plans, programs and arrangements as in effect immediately prior to the
Date of Termination or, if more favorable to the Executive, as in effect
immediately prior to the occurrence of the first event or circumstance
constituting Good Reason.

         5.4 Upon the occurrence of a Change in Control all options to acquire
shares of Company stock, all shares of restricted Company stock and all other
equity or phantom equity incentives held by the Executive under any plan of the
Company (including, but not limited to, the Company's 1995 Stock Award Plan (and
the Stock Matching Programs thereunder) 1993 Stock Option Plan, 1993 Stock Bonus
Plan, 1991 Stock Bonus Plan and Long Term Incentive Plan) shall become
immediately vested, exerciseable and nonforfeitable and all conditions thereof
(including, but not limited to, any required holding periods) shall be deemed to
have been satisfied.

         6. Severance Payments.

         6.1 If the Executive's employment is terminated following a Change in
Control and during the Term, other than (A) by the Company for Cause, (B) by
reason of death or Disability, or (C) by the Executive without Good Reason,
then, the Company shall pay the Executive the amounts, and provide the Executive
the benefits, described in this Section 6.1 ("Severance Payments") and Section
6.2, in addition to any payments and benefits to which the Executive is entitled
under Section 5 hereof. For purposes of this Agreement, the Executive's
employment shall be deemed to have been terminated following a Change in Control
by the Company without Cause or by the Executive with Good Reason, if (i) the
Executive's employment is terminated by the Company without Cause prior to a
Change in Control (whether or not a Change in Control ever

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occurs) and such termination was at the request or direction of a Person who has
entered into an agreement with the Company the consummation of which would
constitute a Change in Control, (ii) the Executive terminates his employment for
Good Reason prior to a Change in Control (whether or not a Change in Control
ever occurs) and the circumstance or event which constitutes Good Reason occurs
at the request or direction of such Person described in clause (i), or (iii) the
Executive's employment is terminated by the Company without Cause or by the
Executive for Good Reason and such termination or the circumstance or event
which constitutes Good Reason is otherwise in connection with or in anticipation
of a Change in Control (whether or not a Change in Control ever occurs). For
purposes of any determination regarding the applicability of the immediately
preceding sentence, any position taken by the Executive shall be presumed to be
correct unless the Company establishes to the Committee by clear and convincing
evidence that such position is not correct.

                  (A) In lieu of any further salary payments to the Executive
     for periods subsequent to the Date of Termination and in lieu of any
     severance benefit otherwise payable to the Executive, the Company shall pay
     to the Executive a lump sum severance payment, in cash, equal to three
     times the sum of (i) the Executive's base salary as in effect immediately
     prior to the Date of Termination or, if higher, in effect immediately prior
     to the first occurrence of an event or circumstance constituting Good
     Reason, and (ii) the average annual bonus earned by the Executive pursuant
     to any annual bonus or incentive plan maintained by the Company in respect
     of the three fiscal years ending immediately prior to the fiscal year in
     which occurs the Date of Termination or, if higher, immediately prior to
     the fiscal year in which occurs the first event or circumstance
     constituting Good Reason;

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     provided, that if the Executive has not participated in an annual bonus or
     incentive plan maintained by the Company for the entirety of such
     three-year period (including those years in which the Company did not
     employ the Executive), for those years in which the Executive has not so
     participated, the amount referred to in this clause (ii) shall be
     calculated using the Executive's Expected Value Bonus level as in effect at
     the time of determination (as defined in the Company's Annual Incentive
     Plan, and assuming for this purpose that any performance goals under such
     Plan for such Plan year have been achieved at the Expected Value level), or
     similar award opportunity under a successor plan thereto.

                  (B) For the thirty-six (36) month period immediately following
     the Date of Termination, the Company shall arrange to provide the Executive
     and his dependents life, disability, accident and health insurance benefits
     and perquisites (including, but not limited to, executive life insurance,
     club memberships, financial planning and tax preparation and annual
     physical examination), in each case, substantially similar to those
     provided to the Executive and his dependents immediately prior to the Date
     of Termination or, if more favorable to the Executive, those provided to
     the Executive and his dependents immediately prior to the first occurrence
     of an event or circumstance constituting Good Reason, at no greater cost to
     the Executive than the cost to the Executive immediately prior to such date
     or occurrence; provided, however, that, unless the Executive consents to a
     different method (after taking into account the effect of such method on
     the calculation of "parachute payments" pursuant to Section 6.2 hereof),
     such health insurance benefits shall be provided through a third-party
     insurer. Benefits otherwise receivable by the Executive pursuant to this
     Section 6.1(B) shall be reduced to the extent benefits of the same type are

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     received by or made available to the Executive during the thirty-six (36)
     month period following the Executive's termination of employment (and any
     such benefits received by or made available to the Executive shall be
     reported to the Company by the Executive); provided, however, that the
     Company shall reimburse the Executive for the excess, if any, of the cost
     of such benefits to the Executive over such cost immediately prior to the
     Date of Termination or, if more favorable to the Executive, the first
     occurrence of an event or circumstance constituting Good Reason.

                  (C) Notwithstanding any provision of the Baker Hughes
     Incorporated 1995 Employee Annual Incentive Compensation Plan (the "Annual
     Incentive Plan"), the Company shall pay to the Executive a lump sum amount,
     in cash, equal to the sum of (i) any unpaid incentive compensation which
     has been allocated or awarded to the Executive for a completed fiscal year
     or other measuring period preceding the Date of Termination under the
     Annual Incentive Plan and which, as of the Date of Termination, is
     contingent only upon the continued employment of the Executive to a
     subsequent date, and (ii) a pro rata portion to the Date of Termination of
     the aggregate value of all contingent incentive compensation awards to the
     Executive for all then uncompleted periods under the Annual Incentive Plan,
     calculated as to each such award by multiplying the award that the
     Executive would have earned on the last day of the performance award
     period, assuming the achievement, at the expected value target level, of
     the individual and corporate performance goals established with respect to
     such award, by the fraction obtained by dividing the number of full months
     and any fractional portion of a month during such performance award period
     through the Date of Termination by the total number of months contained in
     such

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    performance award period; provided, however, that if such termination of
    employment occurs during the same year in which the Change in Control
    occurs, the pro-rate bonus payment referred to in clause (ii) above shall be
    offset by any payments received under the Annual Incentive Plan in
    connection with such Change in Control.

                  (D) In addition to the retirement benefits to which the
     Executive is entitled under the Company's Thrift Plan (the "Thrift Plan")
     and the Company's Supplemental Retirement Plan (the "SRP"), the Company
     shall pay the Executive a lump sum amount, in cash, equal to the present
     value of the employer-provided contributions, deferrals and allocations the
     Executive would have received had he continued to participate, after the
     Date of Termination, in the Thrift Plan and the SRP for three (3)
     additional years, assuming for this purpose that (i) the Executive earned
     compensation for purposes of the Thrift Plan and SRP during such three-year
     period the amount used to calculate the Executive's severance payment under
     subparagraph (A) of this Section 6.1, and (ii) the percentages of
     contributions, deferrals and allocations made under the Thrift Plan and the
     SRP by or on behalf of the Executive during such three-year period are the
     same percentages of contributions, deferrals and allocations in effect on
     the date of the Change in Control or the Date of Termination, whichever is
     more favorable to the Executive.

                  (E) If the Executive would have become entitled to benefits
     under the Company's post-retirement health care or life insurance plans, as
     in effect immediately prior to the Date of Termination or, if more
     favorable to the Executive, as in effect immediately prior to the first
     occurrence of an event or circumstance constituting Good Reason, had the
     Executive's employment terminated at any time during the period of thirty-

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     six (36) months after the Date of Termination, the Company shall provide
     such post-retirement health care or life insurance benefits to the
     Executive and the Executive's dependents commencing on the later of (i) the
     date on which such coverage would have first become available and (ii) the
     date on which benefits described in subsection (B) of this Section 6.1
     terminate.

                  (F) The Company shall provide the Executive with outplacement
     services suitable to the Executive's position for a period of three years
     or, if earlier, until the first acceptance by the Executive of an offer of
     employment.

         6.2 (A) Whether or not the Executive becomes entitled to the Severance
Payments, if any of the payments or benefits received or to be received by the
Executive in connection with a Change in Control or the Executive's termination
of employment (whether pursuant to the terms of this Agreement or any other
plan, arrangement or agreement with the Company, any Person whose actions result
in a Change in Control or any Person affiliated with the Company or such Person)
(such payments or benefits, excluding the Gross-Up Payment, being hereinafter
referred to as the "Total Payments") will be subject to the Excise Tax, the
Company shall pay to the Executive an additional amount (the "Gross-Up Payment")
such that the net amount retained by the Executive, after deduction of any
Excise Tax on the Total Payments and any federal, state and local income and
employment taxes and Excise Tax upon the Gross-Up Payment, shall be equal to the
Total Payments.

             (B) For purposes of determining whether any of the Total Payments
will be subject to the Excise Tax and the amount of such Excise Tax, (i) all of
the Total Payments shall be treated as "parachute payments" (within the meaning
of section 280G(b)(2) of the Code) unless,

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in the opinion of tax counsel ("Tax Counsel") reasonably acceptable to the
Executive and selected by the accounting firm which was, immediately prior to
the Change in Control, the Company's independent auditor (the "Auditor"), such
payments or benefits (in whole or in part) do not constitute parachute payments,
including by reason of section 280G(b)(4)(A) of the Code, (ii) all "excess
parachute payments" within the meaning of section 280G(b)(I) of the Code shall
be treated as subject to the Excise Tax unless, in the opinion of Tax Counsel,
such excess parachute payments (in whole or in part) represent reasonable
compensation for services actually rendered (within the meaning of section
280G(b)(4)(B) of the Code) in excess of the Base Amount allocable to such
reasonable compensation, or are otherwise not subject to the Excise Tax, and
(iii) the value of any noncash benefits or any deferred payment or benefit shall
be determined by the Auditor in accordance with the principles of section
280G(d)(3) and (4) of the Code. For purposes of determining the amount of the
Gross-Up Payment, the Executive shall be deemed to pay federal income tax at the
highest marginal rate of federal income taxation in the calendar year in which
the Gross-Up Payment is to be made and state and local income taxes at the
highest marginal rate of taxation in the state and locality of the Executive's
residence on the Date of Termination (or if there is no Date of Termination,
then the date on which the Gross-Up Payment is calculated for purposes of this
Section 6.2), net of the maximum reduction in federal income taxes which could
be obtained from deduction of such state and local taxes.

             (C) In the event that the Excise Tax is finally determined to be
less than the amount taken into account hereunder in calculating the Gross-Up
Payment, the Executive shall repay to the Company, within five (5) business days
following the time that the amount of such reduction in the Excise Tax is fully
determined, the portion of the Gross-Up Payment attributable

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to such reduction (plus that portion of the Gross-Up Payment attributable to the
Excise Tax and federal, state and local income and employment taxes imposed on
the Gross-Up Payment being repaid by the Executive, to the extent that such
repayment results in a reduction in the Excise Tax and a dollar-for-dollar
reduction in the Executive's taxable income and wages for purposes of federal,
state and local income and employment taxes, plus interest on the amount of such
repayment at 120% of the rate provided in section 1274(b)(2)(B) of the Code. In
the event that the Excise Tax is determined to exceed the amount taken into
account hereunder in calculating the Gross-Up Payment (including by reason of
any payment the existence or amount of which cannot be determined at the time of
the Gross-Up Payment), the Company shall make an additional Gross-Up Payment in
respect of such excess (plus any interest, penalties or additions payable by the
Executive with respect to such excess) within five (5) business days following
the time that the amount of such excess is finally determined. The Executive and
the Company shall each reasonably cooperate with the other in connection with
any administrative or judicial proceedings concerning the existence or amount of
liability for Excise Tax with respect to the Total Payments.

         6.3 The payments provided in subsection (A), (C) and (D) of Section 6.1
hereof and in Section 6.2 hereof shall be made not later than the fifth day
following the Date of Termination; provided, however, that if the amounts of
such payments cannot be finally determined on or before such day, the Company
shall pay to the Executive on such day an estimate, as determined in good faith
by the Executive or, in the case of payments under Section 6.2 hereof, in
accordance with Section 6.2 hereof, of the minimum amount of such payments to
which the Executive is clearly entitled and shall pay the remainder of such
payments (together with interest on the unpaid remainder (or on all such
payments to the extent the Company fails to make such

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payments when due) at 120% of the rate provided in section 1274(b)(2)(B) of the
Code) as soon as the amount thereof can be determined but in no event later than
the thirtieth (30th) day after the Date of Termination. In the event that the
amount of the estimated payments exceeds the amount subsequently determined to
have been due, such excess shall constitute a loan by the Company to the
Executive, payable on the fifth (5th) business day after demand by the Company
(together with interest at 120% of the rate provided in section 1274(b)(2)(B) of
the Code), but only to the extent such amount has not been paid by the Executive
pursuant to Section 6.2(C) above. At the time that payments are made under this
Agreement, the Company shall provide the Executive with a written statement
setting forth the manner in which such payments were calculated and the basis
for such calculations including, without limitation, any opinions or other
advice the Company has received from Tax Counsel, the Auditor or other advisors
or consultants (and any such opinions or advice which are in writing shall be
attached to the statement).

         6.4 The Company also shall pay to the Executive all legal fees and
expenses incurred by the Executive in disputing in good faith any issue
hereunder relating to the termination of the Executive's employment, in seeking
in good faith to obtain or enforce any benefit or right provided by this
Agreement or in connection with any tax audit or proceeding to the extent
attributable to the application of section 4999 of the Code to any payment or
benefit provided hereunder. Such payments shall be made within five (5) business
days after delivery of the Executive's written requests for payment accompanied
with such evidence of fees and expenses incurred as the Company reasonably may
require.

         7. Termination Procedures and Compensation During Dispute.

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         7.1 Notice of Termination. After a Change in Control and during the
Term, any purported termination of the Executive's employment (other than by
reason of death) shall be communicated by written Notice of Termination from one
party hereto to the other party hereto in accordance with Section 10 hereof. For
purposes of this Agreement, a "Notice of Termination" shall mean a notice which
shall indicate the specific termination provision in this Agreement relied upon
and shall set forth in reasonable detail the facts and circumstances claimed to
provide a basis for termination of the Executive's employment under the
provision so indicated. Further, a Notice of Termination for Cause is required
to include a copy of a resolution duly adopted by the affirmative vote of not
less than three-quarters (3/4) of the entire membership of the Board at a
meeting of the Board which was called and held for the purpose of considering
such termination (after reasonable notice to the Executive and an opportunity
for the Executive, together with the Executive's counsel, to be heard before the
Board) finding that, in the good faith opinion of the Board, the Executive was
guilty of conduct set forth in clause (i) or (ii) of the definition of Cause
herein, and specifying the particulars thereof in detail.

         7.2 Date of Termination. "Date of Termination," with respect to any
purported termination of the Executive's employment after a Change in Control
and during the Term, shall mean (i) if the Executive's employment is terminated
for Disability, thirty (30) days after Notice of Termination is given (provided
that the Executive shall not have returned to the full-time performance of the
Executive's duties during such thirty (30) day period), and (ii) if the
Executive's employment is terminated for any other reason, the date specified in
the Notice of Termination (which, in the case of a termination for Cause) and,
in the case of a termination by the Executive,

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shall not be less than fifteen (15) days nor more than sixty (60) days,
respectively, from the date such Notice of Termination is given.

         7.3 Dispute Concerning Termination. If within fifteen (15) days after
any Notice of Termination is given, or, if later, prior to the Date of
Termination (as determined without regard to this Section 7.3), the party
receiving such Notice of Termination notifies the other party that a dispute
exists concerning the termination, the Date of Termination shall be extended
until the earlier of (i) the date on which the Term ends or (ii) the date on
which the dispute is finally resolved, either by mutual written agreement of the
parties or by a final judgment, order or decree of an arbitrator or a court of
competent jurisdiction (which is not appealable or with respect to which the
time for appeal therefrom has expired and no appeal has been perfected);
provided, however, that the Date of Termination shall be extended by a notice of
dispute given by the Executive only if such notice is given in good faith and
the Executive pursues the resolution of such dispute with reasonable diligence.

         7.4 Compensation During Dispute. If a purported termination occurs
following a Change in Control and during the Term and the Date of Termination is
extended in accordance with Section 7.3 hereof, the Company shall continue to
pay the Executive the full compensation in effect when the notice giving rise to
the dispute was given (including, but not limited to, salary) and continue the
Executive as a participant in all compensation, benefit and insurance plans in
which the Executive was participating when the notice giving rise to the dispute
was given or those plans in which the Executive was participating immediately
prior to the first occurrence of an event or circumstance giving rise to the
Notice of Termination, if more favorable to the Executive, until the Date of
Termination, as determined in accordance with Section 7.3 hereof. Amounts paid
under this

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Section 7.4 are in addition to all other amounts due under this Agreement (other
than those due under Section 5.2 hereof) and shall not be offset against or
reduce any other amounts due under this Agreement.

         8. No Mitigation. The Company agrees that, if the Executive's
employment with the Company terminates during the Term, the Executive is not
required to seek other employment or to attempt in any way to reduce any amounts
payable to the Executive by the Company pursuant to Sections 5, 6 or 7.4 hereof.
Further, the amount of any payment or benefit provided for in this Agreement
(other than Section 6.1(B) hereof but including (but not limited to) Section 7.4
hereof) shall not be reduced by any compensation earned by the Executive as the
result of employment by another employer, by retirement benefits, by offset
against any amount claimed to be owed by the Executive to the Company, or
otherwise.

         9. Successors; Binding Agreement.

         9.1 In addition to any obligations imposed by law upon any successor to
the Company, the Company will require any successor (whether direct or indirect,
by purchase, merger, consolidation or otherwise) to all or substantially all of
the business and/or assets of the Company to expressly assume and agree to
perform this Agreement in the same manner and to the same extent that the
Company would be required to perform it if no such succession had taken place.
Failure of the Company to obtain such assumption and agreement prior to the
effectiveness of any such succession shall be a breach of this Agreement and
shall entitle the Executive to compensation from the Company in the same amount
and on the same terms as the Executive would be entitled to hereunder if the
Executive were to terminate the Executive's employment for Good Reason after a

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Change in Control, except that, for purposes of implementing the foregoing, the
date on which any such succession becomes effective shall be deemed the Date of
Termination.

         9.2 This Agreement shall inure to the benefit of and be enforceable by
the Executive's personal or legal representatives, executors, administrators,
successors, heirs, distributees, devisees and legatees. If the Executive shall
die while any amount would still be payable to the Executive hereunder (other
than amounts which, by their terms, terminate upon the death of the Executive)
if the Executive had continued to live, all such amounts, unless otherwise
provided herein, shall be paid in accordance with the terms of this Agreement to
the executors, personal representatives or administrators of the Executive's
estate.

         10. Notices. For the purpose of this Agreement, notices and all other
communications provided for in the Agreement shall be in writing and shall be
deemed to have been duly given when delivered or mailed by United States
registered mail, return receipt requested, postage prepaid, addressed, if to the
Executive, to the address inserted below the Executive's signature on the final
page hereof and, if to the Company, to the address set forth below, or to such
other address as either party may have furnished to the other in writing in
accordance herewith, except that notice of change of address shall be effective
only upon actual receipt:

             To the Company:

             3900 Essex Lane
             Suite 1200
             Houston, Texas 77027

             Attention: General Counsel

         11. Miscellaneous. Except as otherwise specifically provided in Section
12.2 below, no provision of this Agreement may be modified, waived or discharged
unless such waiver,

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modification or discharge is agreed to in writing and signed by the Executive
and such officer as may be specifically designated by the Board. No waiver by
either party hereto at any time of any breach by the other party hereto of, or
of any lack of compliance with, any condition or provision of this Agreement to
be performed by such other party shall be deemed a waiver of similar or
dissimilar provisions or conditions at the same or at any prior or subsequent
time. This Agreement supersedes any other agreements or representations, oral or
otherwise, express or implied, with respect to the subject matter hereof which
have been made by either party, provided, however, that this Agreement shall
supersede any agreement setting forth the terms and conditions of the
Executive's employment with the Company only in the event that the Executive's
employment with the Company is terminated on or following a Change in Control,
by the Company other than for Cause or by the Executive other than for Good
Reason; and provided further that all agreements otherwise superseded by this
Agreement shall be automatically reinstated with full force and effect to the
extent this Agreement is terminated or otherwise rendered inapplicable or
amended in accordance with Section 12.2 hereof. The validity, interpretation,
construction and performance of this Agreement shall be governed by the laws of
the State of Texas. All references to sections of the Exchange Act or the Code
shall be deemed also to refer to any successor provisions to such sections. Any
payments provided for hereunder shall be paid net of any applicable withholding
required under federal, state or local law and any additional withholding to
which the Executive has agreed. The obligations of the Company and the Executive
under this Agreement which by their nature may require either partial or total
performance after the expiration of the Term (including, without limitation,
those under Sections 6 and 7 hereof) shall survive such expiration.

         12. Validity; Pooling.

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         12.1 Validity. The invalidity or unenforceability of any provision of
this Agreement shall not affect the validity or enforceability of any other
provision of this Agreement, which shall remain in full force and effect.

         12.2 Pooling. In the event that (A) the Company is party to a
transaction which is otherwise intended to qualify for "pooling of interests"
accounting treatment, (B) such transaction constitutes a Change in Control
within the meaning of Section 15(G)(III) and (C) individuals who satisfy the
requirements in clauses (i) and (ii) below constitute more than two-thirds (2/3)
of the number of directors of the entity surviving such transaction and the
parent thereof, if any: individuals who (i) immediately prior to such
transaction constitute the Board and (ii) on the date hereof constitute the
Board and any new director (other than a director whose initial assumption of
office is in connection with an actual or threatened election contest relating
to the election of directors of the Company) whose appointment or election by
the Board or nomination for election by the Company's stockholders was approved
or recommended, by a vote of at least two-thirds (2/3) of the directors then
still in office who either were directors on the date hereof or whose
appointment, election or nomination for election was previously so approved or
recommended then (a) this Agreement shall, to the extent practicable, be
interpreted so as to permit such accounting treatment, and (b) to the extent
that the application of clause (a) of this Section 12.2 does not preserve the
availability of such accounting treatment, then, to the extent that any
provision or combination of provisions of the Agreement disqualifies the
transaction as a "pooling" transaction (including, if applicable, the entire
Agreement), the Board shall have the right, by sending written notice to the
Executive prior to the Change in Control, to unilaterally amend (without the
consent of the Executive) such provision or provisions if and to the extent
necessary (including declaring such

                                      -18-
<PAGE>   19

provision or provisions to be null and void as of the date hereof) so that such
transaction may be accounted for as a "pooling of interests." All determinations
under this Section 12.2 shall be made by the Board prior to the Change in
Control, based upon the advice of the accounting firm whose opinion with respect
to "pooling of interests" is required as a condition to the consummation of such
transaction.

         13. Counterparts. This Agreement may be executed in several
counterparts, each of which shall be deemed to be an original but all of which
together will constitute one and the same instrument.

         14. Settlement of Disputes; Arbitration.

         14.1 All claims by the Executive for benefits under this Agreement
shall be directed to and determined by the Committee and shall be in writing.
Any denial by the Committee of a claim for benefits under this Agreement shall
be delivered to the Executive in writing within thirty (30) days after written
notice of the claim is provided to the Company in accordance with Section 10 and
shall set forth the specific reasons for the denial and the specific provisions
of this Agreement relied upon. The Committee shall afford a reasonable
opportunity to the Executive for a review of the decision denying a claim and
shall further allow the Executive to appeal to the Committee a decision of the
Committee within sixty (60) days after notification by the Committee that the
Executive's claim has been denied.

         14.2 Any further dispute or controversy arising under or in connection
with this Agreement shall be settled exclusively by arbitration in Houston,
Texas in accordance with the rules of the American Arbitration Association then
in effect; provided, however, that the evidentiary standards set forth in this
Agreement shall apply. Judgment may be entered on the arbitrator's award

                                      -19-
<PAGE>   20

in any court having jurisdiction. Notwithstanding any provision of this
Agreement to the contrary, the Executive shall be entitled to seek specific
performance of the Executive's right to be paid until the Date of Termination
during the pendency of any dispute or controversy arising under or in connection
with this Agreement.

         15. Definitions. For purposes of this Agreement, the following terms
shall have the meanings indicated below:

         (A) "Affiliate" shall have the meaning set forth in Rule 12b-2
promulgated under Section 12 of the Exchange Act.

         (B) "Auditor" shall have the meaning set forth in Section 6.2 hereof.

         (C) "Base Amount" shall have the meaning set forth in section
280G(b)(3) of the Code.

         (D) "Beneficial Owner" shall have the meaning set forth in Rule 13d-3
under the Exchange Act.

         (E) "Board" shall mean the Board of Directors of the Company.

         (F) "Cause" for termination by the Company of the Executive's
employment shall mean (i) the willful and continued failure by the Executive to
substantially perform the Executive's duties with the Company (other than any
such failure resulting from the Executive's incapacity due to physical or mental
illness or any such actual or anticipated failure after the issuance of a Notice
of Termination for Good Reason by the Executive pursuant to Section 7.1 hereof)
after a written demand for substantial performance is delivered to the Executive
by the Board, which demand specifically identifies the manner in which the Board
believes that the Executive has not substantially performed the Executive's
duties, or (ii) the willful engaging by the Executive in conduct which is

                                      -20-
<PAGE>   21

demonstrably and materially injurious to the Company or its subsidiaries,
monetarily or otherwise. For purposes of clauses (i) and (ii) of this
definition, (x) no act, or failure to act, on the Executive's part shall be
deemed "willful" unless done, or omitted to be done, by the Executive not in
good faith and without reasonable belief that the Executive's act, or failure to
act, was in the best interest of the Company and (y) in the event of a dispute
concerning the application of this provision, no claim by the Company that Cause
exists shall be given effect unless the Company establishes to the Committee by
clear and convincing evidence that Cause exists.

         (G) A "Change in Control" shall be deemed to have occurred if the event
set forth in any one of the following paragraphs shall have occurred:

                  (I) any Person is or becomes the Beneficial Owner, directly or
         indirectly, of securities of the Company (not including in the
         securities beneficially owned by such Person any securities acquired
         directly from the Company or its affiliates) representing 20% or more
         of the combined voting power of the Company's then outstanding
         securities, excluding any Person who becomes such a Beneficial Owner in
         connection with a transaction described in clause (i) of paragraph
         (III) below; or

                  (II) the following individuals cease for any reason to
         constitute a majority of the number of directors then serving:
         individuals who, on the date hereof, constitute the Board and any new
         director (other than a director whose initial assumption of office is
         in connection with an actual or threatened election contest relating to
         the election of directors of the Company) whose appointment or election
         by the Board or nomination for election by the Company's stockholders
         was

                                      -21-
<PAGE>   22

         approved or recommended by a vote of at least two-thirds (2/3) of the
         directors then still in office who either were directors on the date
         hereof or whose appointment, election or nomination for election was
         previously so approved or recommended; or

                  (III) there is consummated a merger or consolidation of the
         Company or any direct or indirect subsidiary of the Company with any
         other corporation, other than (i) a merger or consolidation which would
         result in the voting securities of the Company outstanding immediately
         prior to such merger or consolidation continuing to represent (either
         by remaining outstanding or by being converted into voting securities
         of the surviving entity or any parent thereof), in combination with the
         ownership of any trustee or other fiduciary holding securities under an
         employee benefit plan of the Company or any subsidiary of the Company,
         at least 65% of the combined voting power of the securities of the
         Company or such surviving entity or any parent thereof outstanding
         immediately after such merger or consolidation, or (ii) a merger or
         consolidation effected to implement a recapitalization of the Company
         (or similar transaction) in which no Person is or becomes the
         Beneficial Owner, directly or indirectly, of securities of the Company
         (not including in the securities Beneficially Owned by such Person any
         securities acquired directly from the Company or its Affiliates other
         than in connection with the acquisition by the Company or its
         Affiliates of a business) representing 20% or more of the combined
         voting power of the Company's then outstanding securities; or

                  (IV) the stockholders of the Company approve a plan of
         complete liquidation or dissolution of the Company or there is
         consummated an agreement for

                                      -22-
<PAGE>   23

         the sale or disposition by the Company of all or substantially all of
         the Company's assets, other than a sale or disposition by the Company
         of all or substantially all of the Company's assets to an entity, at
         least 65% of the combined voting power of the voting securities of
         which are owned by stockholders of the Company in substantially the
         same proportions as their ownership of the Company immediately prior to
         such sale.

Notwithstanding the foregoing, a "Change in Control" shall not be deemed to have
occurred by virtue of the consummation of any transaction or series of
integrated transactions immediately following which the record holders of the
common stock of the Company immediately prior to such transaction or series of
transactions continue to have substantially the same proportionate ownership in
an entity which owns all or substantially all of the assets of the Company
immediately following such transaction or series of transactions.

         (H) "Code" shall mean the Internal Revenue Code of 1986, as amended
from time to time.

         (I) "Committee" shall mean (i) the individuals (not fewer than three in
number) who, on the date six months before a Change in Control, constitute the
Compensation Committee of the Board, plus (ii) in the event that fewer than
three individuals are available from the group specified in clause (i) above for
any reason, such individuals as may be appointed by the individual or
individuals so available (including for this purpose any individual or
individuals previously so appointed under this clause (ii)); provided, however,
that the maximum number of individuals constituting the Committee shall not
exceed six (6).

                                      -23-
<PAGE>   24

         (J) "Company" shall mean Baker Hughes Incorporated and, except in
determining under Section 15(G) hereof whether or not any Change in Control of
the Company has occurred, shall include any successor to its business and/or
assets which assumes and agrees to perform this Agreement by operation of law,
or otherwise.

         (K) "Date of Termination" shall have the meaning set forth in Section
7.2 hereof.

         (L) "Disability" shall be deemed the reason for the termination by the
Company of the Executive's employment, if, as a result of the Executive's
incapacity due to physical or mental illness, the Executive shall have been
absent from the full-time performance of the Executive's duties with the Company
for a period of six (6) consecutive months, the Company shall have given the
Executive a Notice of Termination for Disability, and, within thirty (30) days
after such Notice of Termination is given, the Executive shall not have returned
to the full-time performance of the Executive's duties.

         (M) "Exchange Act" shall mean the Securities Exchange Act of 1934, as
amended from time to time.

         (N) "Excise Tax" shall mean any excise tax imposed under section 4999
of the Code.

         (O) "Executive" shall mean the individual named in the first paragraph
of this Agreement.

         (P) "Extension Date" shall have the meaning set forth in Section 2
hereof.

         (Q) "Good Reason" for termination by the Executive of the Executive's
employment shall mean the occurrence (without the Executive's express written
consent) after any Change in Control, or prior to a Change in Control under the
circumstances described in clauses (ii)

                                      -24-
<PAGE>   25

and (iii) of the second sentence of Section 6.1 hereof (treating all references
in paragraphs (I) through (VII) below to a "Change in Control" as references to
a "Potential Change in Control"), of any one of the following acts by the
Company, or failures by the Company to act, unless, in the case of any act or
failure to act described in paragraph (I), (V), (VI) or (VII) below, such act or
failure to act is corrected prior to the Date of Termination specified in the
Notice of Termination given in respect thereof:

                  (I) the assignment to the Executive of any duties inconsistent
         with the Executive's position as Chairman of the Board, President and
         Chief Executive Officer of the Company (including status, office, title
         and reporting requirements), which shall be no less than those of the
         usual and customary duties of such office, which shall be those
         normally inherent in such capacity in U.S. publicly held corporations
         of similar size and character, or a substantial adverse alteration in
         the nature or status of the Executive's responsibilities or authority
         from those in effect immediately prior to the Change in Control;

                  (II) a reduction by the Company in the Executive's annual base
         salary as in effect on the date hereof or as the same may be increased
         from time to time except for across-the-board salary reductions
         similarly affecting all senior executives of the Company and all senior
         executives of any Person in control of the Company;

                  (III) the relocation of the Executive's principal place of
         employment to a location more than 50 miles from the Executive's
         principal place of employment immediately prior to the Change in
         Control or the Company's

                                      -25-
<PAGE>   26

         requiring the Executive to be based anywhere other than such principal
         place of employment (or permitted relocation thereof) except for
         required travel on the Company's business to an extent substantially
         consistent with the Executive's present business travel obligations;

                  (IV) the failure by the Company to pay to the Executive any
         portion of the Executive's current compensation except pursuant to an
         across-the-board compensation deferral similarly affecting all senior
         executives of the Company and all senior executives of any Person in
         control of the Company, or to pay to the Executive any portion of an
         installment of deferred compensation under any deferred compensation
         program of the Company, within seven (7) days of the date such
         compensation is due;

                  (V) the failure by the Company to continue in effect any
         compensation plan in which the Executive participates immediately prior
         to the Change in Control which is material to the Executive's total
         compensation, including but not limited to the Company's 1993 Stock
         Option Plan, 1993 Employee Stock Bonus Plan, 1991 Employee Stock Bonus
         Plan, 1995 Stock Award Plan (and the 1995, 1996 and 1997 Stock Matching
         Programs thereunder and any subsequent Stock Matching Programs in which
         the Executive participates), Long Term Incentive Plan and 1995 Employee
         Annual Incentive Compensation Plan or any substitute plans adopted
         prior to the Change in Control, unless an equitable arrangement
         (embodied in an ongoing substitute or alternative plan) has been made
         with respect to such plan, or the failure by the Company to continue
         the Executive's participation therein (or

                                      -26-
<PAGE>   27

         in such substitute or alternative plan) on a basis not materially less
         favorable, both in terms of the amount or timing of payment of benefits
         provided and the level of the Executive's participation relative to
         other participants, as existed immediately prior to the Change in
         Control;

                  (VI) the failure by the Company to continue to provide the
         Executive with benefits substantially similar to those enjoyed by the
         Executive under any of the Company's pension, savings, life insurance,
         medical, health and accident, or disability plans in which the
         Executive was participating immediately prior to the Change in Control
         (except for across the board changes similarly affecting all senior
         executives of the Company and all senior executives of any Person in
         control of the Company), the taking of any other action by the Company
         which would directly or indirectly materially reduce any of such
         benefits or deprive the Executive of any material fringe benefit or
         perquisite enjoyed by the Executive at the time of the Change in
         Control, or the failure by the Company to provide the Executive with
         the number of paid vacation days to which the Executive is entitled on
         the basis of years of service with the Company in accordance with the
         Company's normal vacation policy in effect at the time of the Change in
         Control; or

                  (VII) any purported termination of the Executive's employment
         which is not effected pursuant to a Notice of Termination satisfying
         the requirements of Section 7.1 hereof; for purposes of this Agreement,
         no such purported termination shall be effective.

                                      -27-
<PAGE>   28

         The Executive's right to terminate the Executive's employment for Good
Reason shall not be affected by the Executive's incapacity due to physical or
mental illness. The Executive's continued employment shall not constitute
consent to, or a waiver of rights with respect to, any act or failure to act
constituting Good Reason hereunder.

         For purposes of any determination regarding the existence of Good
Reason, any claim by the Executive that Good Reason exists shall be presumed to
be correct unless the Company establishes to the Committee by clear and
convincing evidence that Good Reason does not exist.

         (R) "Gross-Up Payment" shall have the meaning set forth in Section 6.2
hereof.

         (S) "Notice of Termination" shall have the meaning set forth in Section
7.1 hereof.

         (T) "Person" shall have the meaning given in Section 3(a)(9) of the
Exchange Act, as modified and used in Sections 13(d) and 14(d) thereof, except
that such term shall not include (i) the Company or any of its subsidiaries,
(ii) a trustee or other fiduciary holding securities under an employee benefit
plan of the Company or any of its Affiliates, (iii) an underwriter temporarily
holding securities pursuant to an offering of such securities, or (iv) a
corporation owned, directly or indirectly, by the stockholders of the Company in
substantially the same proportions as their ownership of stock of the Company.

         (U) "Potential Change in Control" shall be deemed to have occurred if
the event set forth in any one of the following paragraphs shall have occurred:

                  (I) the Company enters into an agreement, the consummation of
         which would result in the occurrence of a Change in Control;

                                      -28-
<PAGE>   29

                  (II) the Company or any Person publicly announces an intention
         to take or to consider taking actions which, if consummated, would
         constitute a Change in Control;

                  (III) any Person becomes the Beneficial Owner, directly or
         indirectly, of securities of the Company representing 15% or more of
         either the then outstanding shares of common stock of the Company or
         the combined voting power of the Company's then outstanding securities
         (not including in the securities beneficially owned by such Person any
         securities acquired directly from the Company or its affiliates); or

                  (IV) the Board adopts a resolution to the effect that, for
         purposes of this Agreement, a Potential Change in Control has occurred.

                  (V) "Retirement" shall, for purposes of Section 4 hereof, be
         deemed the reason for the termination by the Executive of the
         Executive's employment if such employment is terminated after
         completion of ten (10) years of service with the Company and attainment
         of age fifty-five (55).

                  (W) "Severance Payments" shall have the meaning set forth in
         Section 6.1 hereof.

                  (X) "SRP" shall have the meaning set forth in Section 6.1
         hereof.

                  (Y) "Tax Counsel" shall have the meaning set forth in Section
         6.2 hereof.

                  (Z) "Term" shall mean the period of time described in Section
         2 hereof (including any extension, continuation or termination
         described therein).

                                      -29-
<PAGE>   30

                  (AA) "Thrift Plan" shall have the meaning set forth in Section
         6.1 hereof.

                  (BB) "Total Payments" shall mean those payments so described
         in Section 6.2 hereof.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date above first written.

                                       BAKER HUGHES INCORPORATED

                                       By: /s/ JOE B. FOSTER
                                          --------------------------------------
                                          Joe B. Foster
                                          Chairman of the Board, President and
                                            Chief Executive Officer

                                       EXECUTIVE:

                                       /s/ MICHAEL E. WILEY
                                       -----------------------------------------
                                       Michael E. Wiley

                                       Address:
                                       10930 Kemwood Drive
                                       Houston, Texas 77024

                                      -30-<PAGE>   1

                                                                  EXHIBIT 4.2

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

                          SECOND SUPPLEMENTAL INDENTURE

                                     BETWEEN

                        DIAMOND OFFSHORE DRILLING, INC.

                                       AND

                            THE CHASE MANHATTAN BANK,

                                   AS TRUSTEE

                                   ----------

                                   DATED AS OF

                                  JUNE 6, 2000

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

<PAGE>   2

                                TABLE OF CONTENTS

                                   ARTICLE ONE

                               THE 2020 DEBENTURES

<TABLE>
<S>          <C>                                                                    <C>
SECTION 101 Designation of 2020 Debentures; Establishment of Form ..............      2
SECTION 102 Transfer and Exchange ..............................................      3
SECTION 103 Amount .............................................................      8
SECTION 104 Accrual of Original Issue Discount; Interest .......................      9
SECTION 105 Additional Interest ................................................      9
SECTION 106 Denominations ......................................................      9
SECTION 107 Place of Payment ...................................................      9
SECTION 108 Redemption .........................................................      9
SECTION 109 Conversion .........................................................     10
SECTION 110 Maturity ...........................................................     10
SECTION 111 Repurchase .........................................................     10
SECTION 112 Amount Due Upon Event of Default ...................................     10
SECTION 113 Discharge of Liability on 2020 Debentures ..........................     11
SECTION 114 Other Terms of 2020 Debentures .....................................     11

                                   ARTICLE TWO

                           AMENDMENTS TO THE INDENTURE

SECTION 201 Amendments Applicable Only to 2020 Debentures ......................     11
SECTION 202 Definitions ........................................................     11
SECTION 203 Registration, Registration of Transfer and Exchange ................     17
SECTION 204 Mutilated, Destroyed, Lost and Stolen Securities ...................     18
SECTION 205 Payment of Interest; Interest Rights Preserved .....................     18
SECTION 206 Amendment of Article Four of the Indenture .........................     19
SECTION 207 Amendment to Section 501 of the Indenture ..........................     19
SECTION 208 Unconditional Right of Holders to Receive Principal, Premium and
            Interest ...........................................................     21
SECTION 209 Reports by Company .................................................     22
SECTION 210 Consolidation, Merger and Sale .....................................     22
SECTION 211 Supplemental Indentures Without Consent of Holders .................     22
SECTION 212 Supplemental Indenture with Consent of Holder ......................     23
SECTION 213 Amendment to Article Ten of the Indenture ..........................     23
SECTION 214 Maintenance of Office or Agency ....................................     26
SECTION 215 Redemption .........................................................     27
</TABLE>

<PAGE>   3

<TABLE>
<S>     <C>                                                                          <C>
SECTION 216  Conversion, Tax Event, Repurchase .................................     28

                                  ARTICLE THREE

                            MISCELLANEOUS PROVISIONS

SECTION 301  Integral Part .....................................................     57
SECTION 302  General Definitions ...............................................     57
SECTION 303  Adoption, Ratification and Confirmation ...........................     57
SECTION 304  Counterparts ......................................................     58
SECTION 305  Governing Law .....................................................     58
SECTION 306  Conflict of Any Provision of Indenture with Trust Indenture Act of
             193958 ............................................................
SECTION 307  Effect of Headings ................................................     58
SECTION 308  Severability of Provisions ........................................     58
SECTION 309  Successors and Assigns ............................................     58
SECTION 310  Benefit of Second Supplemental Indenture ..........................     58
SECTION 311  Acceptance by Trustee .............................................     59
</TABLE>

                                       ii

<PAGE>   4

                         DIAMOND OFFSHORE DRILLING, INC.

                          SECOND SUPPLEMENTAL INDENTURE

     THIS SECOND SUPPLEMENTAL INDENTURE, dated as of June 6, 2000, between
Diamond Offshore Drilling, Inc., A Delaware corporation (the "Company"), and The
Chase Manhattan Bank, a banking corporation organized and existing under the
laws of the State of New York (the "Trustee").

                                   WITNESSETH

     WHEREAS, the Company has heretofore executed and delivered to the Trustee
an Indenture, dated as of February 4, 1997 (the "Indenture"), providing for the
issuance from time to time of one or more series of the Company's Securities;

     WHEREAS, Section 901(5) of the Indenture provides that the Company and the
Trustee may from time to time enter into one or more indentures supplemental
thereto to establish the form or terms of Securities of a new series;

     WHEREAS, Sections 901(2) and 901(7) of the Indenture permit the execution
of supplemental indentures without the consent of any Holders to add to the
covenants of the Company for the benefit of, and to add any additional Events of
Default with respect to, all or any series of Securities;

     WHEREAS, Section 301 of the Indenture provides that the Company may enter
into supplemental indentures to establish the terms and provisions of a series
of Securities issued pursuant to the Indenture;

     WHEREAS, the Company desires to issue Zero Coupon Convertible Debentures
due June 6, 2020 (the "2020 Debentures"), a new series of Security, the issuance
of which was authorized by resolution of the Executive Committee of the Board of
Directors of the Company, dated May 31, 2000;

     WHEREAS, the Company, pursuant to the foregoing authority, proposes in and
by this Second Supplemental Indenture to supplement and amend in certain
respects the Indenture insofar as it will apply only to the 2020 Debentures (and
not to any other series); and

     WHEREAS, all things necessary have been done to make the 2020 Debentures,
when executed by the Company and authenticated and delivered hereunder and duly
issued by the Company, the valid obligations of the Company, and to make this
Second Supplemental Indenture a valid agreement of the Company, in accordance
with their and its terms.

<PAGE>   5

     NOW THEREFORE:

     In consideration of the premises provided for herein, the Company and the
Trustee mutually covenant and agree for the equal and proportionate benefit of
all Holders of the 2020 Debentures as follows:

                                   ARTICLE ONE

                               THE 2020 DEBENTURES

SECTION 101 Designation of 2020 Debentures; Establishment of Form.

     There shall be a series of Securities designated "Zero Coupon Convertible
Debentures Due June 6, 2020" of the Company, 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 Second 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, consistently herewith, be determined by the officers of the Company
executing such 2020 Debentures, as evidenced by their execution of the 2020
Debentures.

         (a) Restricted Global Securities. All of the 2020 Debentures are
initially being offered and sold to qualified institutional buyers as defined in
Rule 144A (collectively, "QIBs" or individually a "QIB") in reliance on Rule
144A under the Securities Act and shall be issued initially in the form of one
or more Restricted Global Securities, which shall be deposited on behalf of the
purchasers of the 2020 Debentures represented thereby with the Trustee, at its
Corporate Trust Office, as Securities Custodian for the depositary, The
Depository Trust Company ("DTC") (such depositary, or any successor thereto,
being hereinafter referred to as the "Depositary"), and registered in the name
of its nominee, Cede & Co., duly executed by the Company and authenticated by
the Trustee as hereinafter provided. The aggregate Principal Amount of a
Restricted Global Security may from time to time be increased or decreased by
adjustments made on the records of the Securities Custodian as hereinafter
provided, subject in each case to compliance with the Applicable Procedures.

         (b) Global Securities in General. Each Global Security shall represent
such of the outstanding 2020 Debentures as shall be specified therein and each
shall provide that it shall represent the aggregate amount of outstanding 2020
Debentures from time to time endorsed thereon and that the aggregate amount of
outstanding 2020 Debentures represented thereby may from time to time be reduced
or increased, as appropriate, to reflect exchanges, redemptions, purchases or
conversions of such 2020 Debentures. Any endorsement of a Global Security to
reflect the amount of any increase or decrease in the Principal Amount of
Outstanding 2020 Debentures represented

                                       2

<PAGE>   6

thereby shall be made by the Securities Custodian in accordance with the
standing instructions and procedures existing between the Depositary and the
Securities Custodian.

         Members of, or participants in, the Depositary ("Agent Members") shall
have no rights under this Indenture with respect to any Global Security held on
their behalf by the Depositary or under the Global Security, and the Depositary
(including, for this purpose, its nominee) may be treated by the Company, the
Trustee and any agent of the Company or the Trustee as the absolute owner and
Holder of such Global Security for all purposes whatsoever. Notwithstanding the
foregoing, nothing herein shall (A) prevent the Company, the Trustee or any
agent of the Company or the Trustee from giving effect to any written
certification, proxy or other authorization furnished by the Depositary or (B)
impair, as between the Depositary and its Agent Members, the operation of
customary practices governing the exercise of the rights of a Holder of any 2020
Debenture.

         (c) Certificated Securities. Certificated Securities shall be issued
only under the limited circumstances provided in Section 102(a)(1) hereof.

     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 2020 Debentures.

SECTION 102 Transfer and Exchange.

         (a) Transfer and Exchange of Global Securities.

                  (1) Certificated Securities shall be issued in exchange for
         interests in the Global Securities only if (x) the Depositary notifies
         the Company that it is unwilling or unable to continue as depositary
         for the Global Securities or if it at any time ceases to be a "clearing
         agency" registered under the Exchange Act if so required by applicable
         law or regulation and a successor depositary is not appointed by the
         Company within 90 days, or (y) an Event of Default has occurred and is
         continuing. In either case, the Company shall execute, and the Trustee
         shall, upon receipt of a Company Order (which the Company agrees to
         deliver promptly), authenticate and deliver Certificated Securities in
         an aggregate Principal Amount equal to the Principal Amount of such
         Global Securities in exchange therefor. Only Restricted Certificated
         Securities shall be issued in exchange for beneficial interests in
         Restricted Global Securities, and only Unrestricted Certificated
         Securities shall be issued in exchange for beneficial interests in
         Unrestricted Global Securities. Certificated Securities issued in
         exchange for beneficial interests in Global Securities shall be
         registered in such names and shall be in such authorized denominations
         as the Depositary, pursuant to instructions from its direct or indirect
         participants or otherwise, shall instruct the Trustee. The Trustee
         shall deliver or

                                       3

<PAGE>   7

         cause to be delivered such Certificated Securities to the persons in
         whose names such Securities are so registered. Such exchange shall be
         effected in accordance with the Applicable Procedures. Nothing herein
         shall require the Trustee to communicate directly with beneficial
         owners, and the Trustee shall in connection with any transfers
         hereunder be entitled to rely on instructions received through the
         registered Holder.

                  (2) Notwithstanding any other provisions of this Indenture
         other than the provisions set forth in Section 102(a)(1) hereof, a
         Global Security may not be transferred as a whole except by the
         Depositary to a nominee of the Depositary or by a nominee of the
         Depositary to the Depositary or another nominee of the Depositary or by
         the Depositary or any such nominee to a successor Depositary or a
         nominee of such successor Depositary.

         (b) Transfer and Exchange of Certificated Securities. When Certificated
Securities are presented by a Holder to a Registrar with a request:

                  (1) to register the transfer of the Certificated Securities to
         a person who will take delivery thereof in the form of Certificated
         Securities only; or

                  (2) to exchange such Certificated Securities for an equal
         Principal Amount of Certificated Securities of other authorized
         denominations,

such Registrar shall register the transfer or make the exchange as
requested; provided, however, that the Certificated Securities presented or
surrendered for register of transfer or exchange:

                  (1) shall be duly endorsed or accompanied by a written
         instrument of transfer in accordance with the fifth paragraph of
         Section 305 of the Indenture; and

                  (2) in the case of a Restricted Certificated Security, such
         request shall be accompanied by the following additional information
         and documents, as applicable:

                           (A) if such Restricted Certificated Security is being
                  delivered to the Registrar by a Holder for registration in the
                  name of such Holder, without transfer, or such Restricted
                  Certificated Security is being transferred to the Company or a
                  Subsidiary of the Company, a certification to that effect from
                  such Holder (in substantially the form set forth in the
                  Transfer Certificate required pursuant to Section 102(e)(1)
                  hereof);

                           (B) if such Restricted Certificated Security is being
                  transferred to a person the Holder reasonably believes is a
                  QIB in accordance with Rule 144A or

                                       4

<PAGE>   8

                  pursuant to an effective registration statement under the
                  Securities Act, a certification to that effect from such
                  Holder (in substantially the form set forth in the Transfer
                  Certificate); or

                           (C) if such Restricted Certificated Security is being
                  transferred (i) pursuant to an exemption from the registration
                  requirements of the Securities Act in accordance with Rule 144
                  or (ii) pursuant to an exemption from the registration
                  requirements of the Securities Act (other than pursuant to
                  Rule 144A or Rule 144) and as a result of which, in the case
                  of a Security transferred pursuant to this clause (ii), such
                  Security shall cease to be a "restricted security" within the
                  meaning of Rule 144, a certification to that effect from the
                  Holder (in substantially the form set forth in the Transfer
                  Certificate) and, if the Company or such Registrar so
                  requests, a customary opinion of counsel, certificates and
                  other information reasonably acceptable to the Company and
                  such Registrar to the effect that such transfer is in
                  compliance with the Securities Act.

         (c) Transfer of a Beneficial Interest in a Restricted Global Security
for a Beneficial Interest in an Unrestricted Global Security. Any person having
a beneficial interest in a Restricted Global Security may upon request, subject
to the Applicable Procedures, transfer such beneficial interest to a person who
is required or permitted to take delivery thereof in the form of an Unrestricted
Global Security. Upon receipt by the Trustee of written instructions or such
other form of instructions as is customary for the Depositary, from the
Depositary or its nominee on behalf of any person having a beneficial interest
in a Restricted Global Security and the following additional information and
documents in such form as is customary for the Depositary from the Depositary or
its nominee on behalf of the person having such beneficial interest in the
Restricted Global Security (all of which may be submitted by facsimile or
electronically):

                  (1) if such beneficial interest is being transferred pursuant
         to an effective registration statement under the Securities Act, a
         certification to that effect from the transferor (in substantially the
         form set forth in the Transfer Certificate); or

                  (2) if such beneficial interest is being transferred (i)
         pursuant to an exemption from the registration requirements of the
         Securities Act in accordance with Rule 144 or (ii) pursuant to an
         exemption from the registration requirements of the Securities Act
         (other than pursuant to Rule 144A or Rule 144) and as a result of
         which, in the case of a Security transferred pursuant to this clause
         (ii), such Security shall cease to be a "restricted security" within
         the meaning of Rule 144, a certification to that effect from the
         transferor (in substantially the form set forth in the Transfer
         Certificate) and, if the Company or the Trustee so requests, a
         customary opinion of counsel, certificates and other information
         reasonably acceptable to the Company and the Trustee to the effect that
         such transfer is in compliance with the Securities Act,

                                       5

<PAGE>   9

         the Trustee, as a Registrar and Securities Custodian, shall reduce or
         cause to be reduced the aggregate Principal Amount of the Restricted
         Global Security by the appropriate Principal Amount and shall increase
         or cause to be increased the aggregate Principal Amount of the
         Unrestricted Global Security by a like Principal Amount. Such transfer
         shall otherwise be effected in accordance with the Applicable
         Procedures. If no Unrestricted Global Security is then outstanding, the
         Company shall execute and the Trustee shall, upon receipt of a Company
         Order (which the Company agrees to deliver promptly), authenticate and
         deliver an Unrestricted Global Security.

     (d) Transfers of Certificated Securities for Beneficial Interest in Global
Securities. In the event that Certificated Securities are issued in exchange for
beneficial interests in Global Securities and, thereafter, the events or
conditions specified in Section 102(a)(1) hereof which required such exchange
shall have ceased to exist, the Company shall mail notice to the Trustee and to
the Holders stating that Holders may exchange Certificated Securities for
interests in Global Securities by complying with the procedures set forth in
this Indenture and briefly describing such procedures and the events or
circumstances requiring that such notice be given. Thereafter, if Certificated
Securities are presented by a Holder to a Registrar with a request:

                  (1) to register the transfer of such Certificated Securities
         to a person who will take delivery thereof in the form of a beneficial
         interest in a Global Security, which request shall specify whether
         such Global Security will be a Restricted Global Security or an
         Unrestricted Global Security; or

                  (2) to exchange such Certificated Securities for an equal
         Principal Amount of beneficial interests in a Global Security, which
         beneficial interests will be owned by the Holder transferring such
         Certificated Securities (provided that in the case of such an exchange,
         Restricted Certificated Securities may be exchanged only for Restricted
         Global Securities and Unrestricted Certificated Securities may be
         exchanged only for Unrestricted Global Securities),

the Registrar shall register the transfer or make the exchange as requested by
canceling such Certificated Security and causing, or directing the Securities
Custodian to cause, the aggregate Principal Amount of the applicable Global
Security to be increased accordingly and, if no such Global Security is then
outstanding, the Company shall issue and the Trustee shall authenticate and
deliver a new Global Security; provided, however, that the Certificated
Securities presented or surrendered for registration of transfer or exchange:

                  (1) shall be duly endorsed or accompanied by a written
         instrument of transfer in accordance with the fifth paragraph of
         Section 305 of the Indenture;

                  (2) in the case of a Restricted Certificated Security to be
         transferred for a beneficial interest in an Unrestricted Global
         Security, such request shall be accompanied by the following additional
         information and documents, as applicable:

                                       6

<PAGE>   10

                           (A) if such Restricted Certificated Security is being
                  transferred pursuant to an effective registration statement
                  under the Securities Act, a certification to that effect from
                  such Holder (in substantially the form set forth in the
                  Transfer Certificate); or

                           (B) if such Restricted Certificated Security is being
                  transferred pursuant to (i) an exemption from the registration
                  requirements of the Securities Act in accordance with Rule 144
                  or (ii) pursuant to an exemption from the registration
                  requirements of the Securities Act (other than pursuant to
                  Rule 144A or Rule 144) and as a result of which, in the case
                  of a Security transferred pursuant to this clause (ii), such
                  Security shall cease to be a "restricted security" within the
                  meaning of Rule 144, a certification to that effect from such
                  Holder (in substantially the form set forth in the Transfer
                  Certificate), and, if the Company or the Registrar so
                  requests, a customary opinion of counsel, certificates and
                  other information reasonably acceptable to the Company and the
                  Trustee to the effect that such transfer is in compliance with
                  the Securities Act;

                  (3) in the case of a Restricted Certificated Security to be
         transferred or exchanged for a beneficial interest in a Restricted
         Global Security, such request shall be accompanied by a certification
         from such Holder (in substantially the form set forth in the Transfer
         Certificate) to the effect that such Restricted Certificated Security
         is being transferred to a person the Holder reasonably believes is a
         QIB (which, in the case of an exchange, shall be such Holder) in
         accordance with Rule 144A; and

                  (4) in the case of an Unrestricted Certificated Security to be
         transferred or exchanged for a beneficial interest in an Unrestricted
         Global Security, such request need not be accompanied by any additional
         information or documents.

         (e) Legends.

                  (1) Except as permitted by the following paragraphs (2) and
         (3), each Global Security and Certificated Security (and all Securities
         issued in exchange therefor or upon registration of transfer or
         replacement thereof and any Common Stock issuable upon conversion
         thereof) shall bear a legend in substantially the form called for by
         footnote 2 to Annex A hereto (each a "Transfer Restricted Security" for
         so long as such Security or Common Stock issuable upon conversion
         thereof is required by this Indenture to bear such legend). Each
         Transfer Restricted Security shall have attached thereto a certificate
         (a "Transfer Certificate") in substantially the form called for by
         footnote 5 to Annex A hereto.

                  (2) Upon any sale or transfer of a Transfer Restricted
         Security (x) pursuant to Rule 144, (y) pursuant to an effective
         registration statement under the

                                       7
<PAGE>   11
     Securities Act or (z) pursuant to any other available exemption (other than
     Rule 144A) from the registration requirements of the Securities Act and as
     a result of which, in the case of a Security transferred pursuant to this
     clause (z), such Security shall cease to be a "restricted security" within
     the meaning of Rule 144:

                    (A) in the case of any Restricted Certificated Security, any
          Registrar shall permit the Holder thereof to exchange such Restricted
          Certificated Security for an Unrestricted Certificated Security, or
          (under the circumstances described in Section 102(d) hereof) to
          transfer such Restricted Certificated Security to a transferee who
          shall take such Security in the form of a beneficial interest in an
          Unrestricted Global Security, and in each case shall rescind any
          restriction on the transfer of such Security; provided, however, that
          the Holder of such Restricted Certificated Security shall, in
          connection with such exchange or transfer, comply with the other
          applicable provisions of this Section 102; and

                    (B) in the case of any beneficial interest in a Restricted
          Global Security, the Trustee shall permit the beneficial owner thereof
          to transfer such beneficial interest to a transferee who shall take
          such interest in the form of a beneficial interest in an Unrestricted
          Global Security and shall rescind any restriction on transfer of such
          beneficial interest; provided, however, that such Unrestricted Global
          Security shall continue to be subject to the provisions of Section
          102(a)(2) hereof; and provided further, however, that the owner of
          such beneficial interest shall, in connection with such transfer,
          comply with the other applicable provisions of this Section 102.

               (3) Upon the exchange, registration of transfer or replacement of
     Securities not bearing the legend described in paragraph (1) above, the
     Company shall execute, the Trustee shall authenticate and deliver
     Securities that do not bear such legend and which do not have a Transfer
     Certificate attached thereto.

          (f) Transfers to the Company. Nothing in this Indenture or in the
Securities shall prohibit the sale or other transfer of any Securities
(including beneficial interests in Global Securities) to the Company or any of
its Subsidiaries, which Securities shall thereupon be canceled in accordance
Section 309 of the Indenture.

SECTION 103 Amount.

          (a) The Trustee shall authenticate and deliver 2020 Debentures for
original issue in an aggregate Principal Amount of up to $805,000,000 upon
Company Order for the authentication and delivery of 2020 Debentures, without
any further action by the Company. The aggregate Principal Amount of 2020
Debentures that may be authenticated and delivered under the Indenture may not
exceed the amount set forth in the foregoing sentence, except for 2020
Debentures

                                       8

<PAGE>   12

authenticated and delivered upon registration of transfer of, or in exchange
for, or in lieu of, other 2020 Debentures pursuant to Section 204,304,305,306,
906 or 1107 of the Indenture.

          (b) The Company may not issue new 2020 Debentures to replace 2020
Debentures that it has paid or delivered to the Trustee for cancellation or that
any Holder has converted pursuant to Article Fourteen.

SECTION 104 Accrual of Original Issue Discount; Interest.

     The 2020 Debentures shall be Original Issue Discount Securities. Original
Issue Discount shall accrue with respect to the 2020 Debentures at the rate set
forth under the caption "Interest" in the 2020 Debentures, commencing on the
Issue Date of the 2020 Debentures. Except as provided under the caption "Tax
Event" in the 2020 Debentures and in Article Sixteen hereof, there shall be no
periodic payments of interest on the 2020 Debentures.

SECTION 105 Additional Interest.

     Additional Interest with respect to the 2020 Debentures shall be payable in
accordance with the provisions and in the amounts set forth in the Registration
Rights Agreement.

SECTION 106 Denominations.

     The 2020 Debentures shall be in fully registered form without coupons in
denominations of $1,000 of Principal Amount or any integral multiple thereof.

SECTION 107 Place of Payment.

     The Place of Payment for the 2020 Debentures and the place or places where
the 2020 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 2020 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, however, 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 (as
defined in the Indenture).

SECTION 108 Redemption.

          (a) There shall be no sinking fund for the retirement of the 2020
Debentures.

          (b) The Company, at its option, may redeem the 2020 Debentures in
accordance with the provisions of and at the Redemption Prices set forth under
the captions "Optional Redemption" and "Notice of Redemption" in the 2020
Debentures and in accordance with the provisions of the Indenture, including,
without limitation, Article Eleven.

                                       9

<PAGE>   13

SECTION 109 Conversion.

     The 2020 Debentures shall be convertible in accordance with the provisions
and at the Conversion Rate set forth under the caption "Conversion" in the 2020
Debentures and in accordance with the provisions of the Indenture, including,
without limitation, Article Fourteen.

SECTION 110 Maturity.

     The date on which the principal of the 2020 Debentures matures and is
payable, unless accelerated or required to be repurchased pursuant to the
Indenture, shall be June 6, 2020.

SECTION 111 Repurchase.

          (a) The 2020 Debentures shall be repurchased by the Company in
accordance with the provisions and at the Repurchase Prices set forth under the
caption "Repurchase by the Company at the Option of the Holder" in the 2020
Debentures and in accordance with the provisions of the Indenture, including,
without limitation, Article Fifteen.

          (b) The 2020 Debentures shall be repurchased by the Company in
accordance with the provisions of and at the Change in Control Purchase Prices
set forth under the caption "Purchase of Securities at Option of Holder Upon a
Change in Control" in the 2020 Debentures and in accordance with the provisions
of the Indenture, including, without limitation, Article Sixteen.

SECTION 112 Amount Due Upon Event of Default.

     If an Event of Default described in paragraph (1), (2), (3) or (4) (if the
Event of Default under paragraph (3) is with respect to less than all series of
Securities then Outstanding) of Section 501 occurs and is continuing with
respect to any series, then and in each and every such case, unless the
principal of all the 2020 Debentures shall have already become due and payable,
either the Trustee or the Holders of not less than 25% in aggregate Principal
Amount of the 2020 Debentures then Outstanding hereunder (acting as a separate
class), by notice in writing to the Company (and to the Trustee if given by
Holders), may declare the Issue Price plus accrued Original Issue Discount of
all the 2020 Debentures then Outstanding (or, if the 2020 Debentures have been
converted to interest bearing 2020 Debentures pursuant to Section 1701, the
Restated Principal Amount and all accrued interest thereon from the date of such
conversion) to be due and payable immediately, and upon any such declaration the
same shall become and shall be immediately due and payable, anything in this
Indenture or in the Securities of such series contained to the contrary
notwithstanding. If an Event of Default described in paragraph (3) (if the Event
of Default under paragraph (3) is with respect to all series of Securities then
Outstanding) of Section 501 occurs and is continuing, then and in each and every
such case, unless the principal of all the Securities shall have already become
due and payable, either the Trustee or the holders of not less than 25% in
aggregate principal amount of all the Securities then Outstanding hereunder
(or, in the case of the 2020 Debentures, such specified portion of the Principal
Amount treated as one class), by notice in writing to the Company (and to

                                       10

<PAGE>   14

the Trustee if given by Holders), may declare the principal amount (or, in the
case of the 2020 Debentures, such specified portion of the Principal Amount) of
all the Securities then Outstanding and all accrued interest thereon to be due
and payable immediately, and upon any such declaration the same shall become and
shall be immediately due and payable, anything in this Indenture or in the
Securities contained to the contrary notwithstanding. If an Event of Default
described in paragraph (5) or (6) occurs and is continuing, then the principal
amount (or, in the case of the 2020 Debentures, such specified portion of the
Principal Amount) of all the Securities then Outstanding and all accrued
interest thereon shall become and be due and payable immediately, without any
declaration or other act by the Trustee or any other Holder, anything in this
Indenture or in the Securities contained to the contrary notwithstanding.

SECTION 113 Discharge of Liability on 2020 Debentures.

     The 2020 Debentures may be discharged by the Company in accordance with the
provisions of Article Four of the Indenture, as amended by Section 205 hereof.

SECTION 114 Other Terms of 2020 Debentures.

     Without limiting the foregoing provisions of this Article One, the terms of
the 2020 Debentures shall be as set forth in the form of the 2020 Debentures set
forth in Annex A hereto and as provided in the Indenture.

                                   ARTICLE TWO

                           AMENDMENTS TO THE INDENTURE

SECTION 201 Amendments Applicable Only to 2020 Debentures.

     The amendments contained herein shall apply to the 2020 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 2020
Debentures and not for the benefit of any other series of Security issued under
the Indenture. These amendments shall be effective for so long as there remain
any 2020 Debentures Outstanding.

SECTION 202 Definitions.

     Section 101 of the Indenture is hereby amended, subject to Section 201
hereof and with respect to the 2020 Debentures only, by inserting or restating,
as the case may be, in their appropriate alphabetical position, the following
definitions:

     "Additional Interest" shall have the meaning set forth in the Registration
Rights Agreement.

     "Agent Members" has the meaning specified in Section 101.

                                       11

<PAGE>   15

     "Applicable Procedures" means, with respect to any transfer or exchange of
beneficial ownership interests in a Global Security, the rules and procedures of
the Depositary that are applicable to such transfer or exchange.

     "Beneficial Owner" has the meaning specified in Section 1601(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 equity interests (however designated) issued by that
Person.

     "Certificated Security" means a Security that is in substantially the form
attached hereto as Annex A and that does not include the information or the
schedule called for by footnotes 1, 3 and 4 thereof.

     "Change in Control" has the meaning specified in Section 1601.

     "Change in Control Purchase Date" has the meaning specified in Section
1601.

     "Change in Control Purchase Notice" has the meaning specified in Section
1601.

     "Change in Control Purchase Price" has the meaning specified in Section
1601.

     "Common Stock" means any stock of any class of the Company (including,
without limitation, the Company's common stock, par value $0.01 per share) which
has no preference in respect of dividends or of amounts payable in the event of
any voluntary or involuntary liquidation, dissolution or winding up of the
Company and which is not subject to redemption by the Company.

     "Company Notice Date" has the meaning specified in Section 1503.

     "Consolidated Net Tangible Assets" means the total amount of assets (less
applicable reserves and other properly deductible items) after deducting (1) all
current liabilities (excluding the amount of those which are by their terms
extendable or renewable at the option of the obligor to a date more than 12
months after the date as of which the amount is being determined) and (2) all
goodwill, tradenames, trademarks, patents, unamortized debt discount and expense
and other like intangible assets, all as set forth on the most recent balance
sheet of the Company and its consolidated subsidiaries and determined in
accordance with generally accepted accounting principles.

     "Consolidated Net Worth" means, at any time, the Net Worth of the Company
and its Subsidiaries on a consolidated basis determined in accordance with GAAP.

     "Conversion Agent" shall be the agent specified in Section 101.

                                       12

<PAGE>   16

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

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

     "Depositary" has the meaning specified in Section 101.

     "Determination Date" has the meaning specified in Section 1406(d)(l).

     "DTC" has the meaning specified in Section 101.

     "Exchange Act" means the Securities Exchange Act of 1934, as amended, or
any successor statute.

     "Expiration Date" has the meaning specified in Section 1406(d)(2).

     "Expiration Time" has the meaning specified in Section 1406(d)(2).

     "Funded Debt" means indebtedness of the Company or a Subsidiary owning
Restricted Property maturing by its terms more than one year after its creation
and indebtedness classified as long-term debt under generally accepted
accounting principles, and in each case ranking at least pari passu with the
Securities.

     "GAAP" means generally accepted accounting principles as in effect on the
date of determination in the United States.

     "Global Security" means a permanent Global Security that is in
substantially the form attached hereto as Annex A and that includes the
information and schedule called for by footnotes 1, 3 and 4 thereof and which is
deposited with the Depositary or the Securities Custodian and registered in the
name of the Depositary or its nominee.

     "Group" has the meaning specified in Section 1601(a).

     "Indenture" has the meaning specified in the recitals.

     "Issue Date" of any 2020 Debenture means the date on which the 2020
Debenture was originally issued or deemed issued as set forth on the face of the
2020 Debenture.

     "Issue Price" of any 2020 Debenture means, in connection with the original
issuance of such 2020 Debenture, the initial issue price at which the 2020
Debenture is sold as set forth on the face of the 2020 Debenture.

     "Lien" means any mortgage, pledge, lien, encumbrance, charge or security
interest.

                                       13

<PAGE>   17

     "Market Price" has the meaning specified in Section 1504.

     "Net Worth" means, at any time with respect to the Company or a Subsidiary
thereof, the net worth of the Company or such Subsidiary, as the case may be,
determined in accordance with GAAP.

     "NYSE" has the meaning specified in Section 1406(e).

     "Option Exercise Date" has the meaning specified in Section 1701.

     "Original Issue Discount" of any 2020 Debenture means the difference
between the Issue Price and the Principal Amount of the 2020 Debenture as set
forth on the face of the 2020 Debenture.

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

          (1) Securities theretofore cancelled by the Trustee or delivered to
the Trustee for cancellation;

          (2) Securities for whose payment, repurchase or redemption money or
Common Stock 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 Securities; provided that, if such Securities 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;

          (3) Securities which have been cancelled pursuant to Section 309 or in
exchange for or in lieu of which other Securities have been authenticated and
delivered pursuant to this Indenture, other than any such Securities in respect
of which there shall have been presented to the Trustee proof satisfactory to it
that such Securities are held by a bona fide purchaser in whose hands such
Securities are valid obligations of the Company; and

          (4) 2020 Debentures converted for Common Stock pursuant to Article
Fourteen;

provided, however, that in determining whether the Holders of the requisite
principal amount of the Outstanding Securities have given any request, demand,
authorization, direction, notice, consent or waiver hereunder, Securities owned
by the Company or any other obligor upon the Securities 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 Securities which the Trustee knows to be so owned shall
be so disregarded. Securities 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 Securities and that
the pledgee is not the

                                       14

<PAGE>   18

Company or any other obligor upon the Securities or any Affiliate of the Company
or of such other obligor.

     "Permitted Holders" has the meaning specified in Section 1601.

     "Principal Amount" of a 2020 Debenture means the principal amount due at
the Stated Maturity of the 2020 Debentures as set forth on the face of the 2020
Debenture.

     "Purchased Shares" has the meaning specified in Section 1406(d)(2).

     "QIB" has the meaning specified in Section 101.

     "Registration Rights Agreement" means the Registration Rights Agreement,
dated as of June 6, 2000, between the Company and Credit Suisse First Boston
Corporation.

     "Regulation S" means Regulation S under the Securities Act or any successor
to such Rule.

     "Repurchase Date" has the meaning specified in Section 1501.

     "Repurchase Notice" has the meaning specified in Section 1501.

     "Repurchase Price" has the meaning specified in Section 1501.

     "Restated Principal Amount" has the meaning specified in Section 1701.

     "Restricted Certificated Security" means a Certificated Security which is a
Transfer Restricted Security.

     "Restricted Global Security" means a Global Security that is a Transfer
Restricted Security.

     "Restricted Property" means (1) any drilling rig or drillship which is
leased by the Company or any Subsidiary as a lessee, or greater than a 50%
interest in which is owned by the Company or any Subsidiary, and which is used
for drilling offshore oil and gas wells, which, in the opinion of the Board of
Directors, is of material importance to the business of the Company and its
Subsidiaries taken as a whole, but no such drilling rig or drillship, or portion
thereof, shall be deemed of material importance if its net book value is less
than 2% of Consolidated Net Tangible Assets, or (2) any shares of capital stock
or indebtedness of any Subsidiary owning any such drilling rig or drillship.

     "Rule 144" means Rule 144 under the Securities Act or any successor to such
Rule.

     "Rule 144A" means Rule 144A under the Securities Act or any successor to
such Rule.

                                       15

<PAGE>   19

     "Sale and Leaseback Transaction" means any arrangement with any Person
pursuant to which the Company or any Subsidiary leases any Restricted Property
that has been or is to be sold or transferred by the Company or the Subsidiary
to such Person, other than (1) leases for a term, including renewals at the
option of the lessee, of not more than five years, (2) leases between the
Company and a Subsidiary or between Subsidiaries, (3) leases of a Restricted
Property executed by the time of, or within 12 months after the latest of, the
acquisition, the completion of construction or improvement, or the commencement
of commercial operation of the Restricted Property, and (4) arrangements
pursuant to any provision of law with an effect similar to the former Section
168(f)(8) of the Internal Revenue Code of 1954.

     "Sale Price" has the meaning specified in Section 1504.

     "Securities" means any securities authenticated and delivered under the
Indenture, as the same may be amended or supplemented, including 2020
Debentures.

     "Securities Act" means the Securities Act of 1933, as amended, or any
successor statute.

     "Securities Custodian" means the Trustee, as custodian with respect to the
Securities in global form, or any successor thereto.

     "Significant Subsidiary" means any Subsidiary, the Net Worth of which
represents more than 10% of the Consolidated Net Worth of the Company and its
Subsidiaries.

     "Tax Event" means that the Company shall have received an opinion from
independent tax counsel experienced in such matters to the effect that, on or
after June 6, 2000, 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, in each case, which amendment or
change is enacted, promulgated, issued or announced or which interpretation is
issued or announced or which action is taken, on or after June 6, 2000, there
is more than an insubstantial risk that interest (including Original Issue
Discount) payable on the 2020 Debentures 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 1701.

     "Tender Offer" has the meaning specified in Section 1406(d)(3).

     "Trading Day" means a day during which trading in securities generally
occurs on the New York Stock Exchange or, if the Common Stock is not listed on
the New York Stock Exchange, on the principal other national or regional
securities exchange on which the Common Stock is then

                                       16

<PAGE>   20

listed or, if the Common Stock is not listed on a national or regional
securities exchange, on the National Association of Securities Dealers Automated
Quotation System or, if the Common Stock is not quoted on the National
Association of Securities Dealers Automated Quotation System, on the other
principal market on which the Common Stock are then traded.

     "Transfer Certificate" has the meaning specified in Section 102(e)(l).

     "Transfer Restricted Securities" has the meaning specified in Section
102(e)(1).

     "Trigger Event" has the meaning specified in Section 1406(c).

     "Triggering Distribution" has the meaning specified in Section 1406(d)(l).

     "2020 Debentures" has the meaning specified in the recitals.

     "Unrestricted Certificated Security" means a Certificated Security which is
not a Transfer Restricted Security.

     "Unrestricted Global Security" means a Global Security which is not a
Transfer Restricted Security.

     "Value" means, with respect to a Sale and Leaseback Transaction, an amount
equal to the present value of the lease payments with respect to the term of the
lease remaining on the date as of which the amount is being determined, without
regard to any renewal or extension options contained in the lease (including the
effective interest rate on any original issue discount Securities), which are
outstanding on the effective date of such Sale and Leaseback Transaction and
which have the benefit of Section 1010.

     "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 203 Registration, Registration of Transfer and Exchange.

     The Indenture is hereby amended, subject to Section 201 hereof and with
respect to the 2020 Debentures only, 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

                                       17

<PAGE>   21
         business on the day of such mailing, (ii) to register the transfer of
         or exchange any 2020 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 2020
         Debenture or portions thereof in respect of which a Change in Control
         Purchase Notice or Repurchase Notice has been delivered and not
         withdrawn by the Holder thereof (except, in the case of the purchase of
         a 2020 Debenture in part, the portion not to be purchased).

SECTION 204 Mutilated, Destroyed, Lost and Stolen Securities.

         The Indenture is hereby amended, subject to Section 201 hereof and with
respect to the 2020 Debentures only, by replacing the second 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 Change in Control pursuant to
         Article Eleven or purchased by the Company on a Repurchase Date
         pursuant to Article Fifteen, the Company in its discretion may, instead
         of issuing a new Security, pay such Security.

SECTION 205 Payment of Interest; Interest Rights Preserved.

         The Indenture is hereby amended, subject to Section 201 hereof and with
respect to the 2020 Debentures only, by inserting the following paragraph before
the final paragraph in Section 307:

                  In the event the Company exercises its option pursuant to
         Section 1701, then in the case of any 2020 Debenture or portion thereof
         which is surrendered for conversion after the Regular Record Date
         immediately preceding any Interest Payment Date and on or prior to such
         next succeeding Interest Payment Date (unless such 2020 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 2020
         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 2020 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 2020 Debenture which is converted, interest whose
         Stated Maturity is after the date of conversion of such 2020 Debenture
         shall not be payable.

                                       18

<PAGE>   22

SECTION 206 Amendment of Article Four of the Indenture.

         Article Four of the Indenture is hereby amended, subject to Section 201
hereof and with respect to the 2020 Debentures only, by deleting Sections 401,
402 and 403 and replacing those sections with the following:

         SECTION 401 Discharge of Liability on Securities.

                  When (i) the Company delivers to the Trustee or any Paying
         Agent all outstanding 2020 Debentures (other than 2020 Debentures
         replaced pursuant to Section 306) for cancellation or (ii) all
         outstanding 2020 Debentures have become due and payable and the Company
         deposits with the Trustee or any Paying Agent cash or, if expressly
         permitted by the terms of the 2020 Debentures, Common Stock sufficient
         to pay all amounts due and owing on all outstanding 2020 Debentures
         (other than 2020 Debentures replaced pursuant to Section 306), and if
         in either case the Company pays all other sums payable hereunder by the
         Company, then this Indenture shall, subject to Section 607, cease to be
         of further effect, except for the indemnification of the Trustee, which
         shall survive. The Trustee shall join in the execution of a document
         prepared by the Company acknowledging satisfaction and discharge of
         this Indenture on demand of the Company accompanied by an Officers'
         Certificate and Opinion of Counsel and at the cost and expense of the
         Company.

         SECTION 402 Repayment to the Company.

                  The Trustee and the Paying Agent shall return to the Company
         upon written request any money or securities held by them for the
         payment of any amount with respect to the 2020 Debentures that remains
         unclaimed for two years, subject to applicable unclaimed property law.
         After return to the Company, Holders entitled to the money or
         securities must look to the Company for payment as general creditors
         unless an applicable abandoned property law designates another person
         and the Trustee and the Paying Agent shall have no further liability to
         the Holders of 2020 Debentures with respect to such money or securities
         for that period commencing after the return thereof.

SECTION 207 Amendment to Section 501 of the Indenture.

         Section 501 of the Indenture is hereby amended, subject to Section 201
hereof and with respect to the 2020 Debentures only, by deleting subsections
(1), (2), (3), (4), (5) and (6) thereof, and inserting the following as new
subsections (1), (2), (3), (4), (5) and (6) thereof:

                  (1) default in the payment of any interest upon any 2020
         Debenture when it becomes due and payable, after conversion of the 2020
         Debentures to

                                       19

<PAGE>   23

         interest bearing 2020 Debentures pursuant to Section 1701, or in the
         payment of any Additional Interest pursuant to the Registration Rights
         Agreement, and continuance of such default for a period of 30 days; or

                  (2) default in the payment of the Principal Amount at Maturity
         (or, if the 2020 Debentures have been converted to interest-bearing
         2020 Debentures pursuant to Section 1701, the Restated Principal
         Amount), the Redemption Price, the Repurchase Price or the Change in
         Control Purchase Price of any 2020 Debenture at its Maturity, upon
         redemption, upon declaration of acceleration, when due for repurchase
         by the Company or otherwise; or

                  (3) default by the Company in the performance, or breach, of
         any covenant or warranty of the Company in this Indenture (other than a
         covenant or warranty a default in whose performance or whose breach is
         elsewhere in this Section 501 specifically dealt with), and continuance
         of such default or breach for a period of 60 days after there has been
         given, by registered or certified mail, to the Company by the Trustee
         or to the Company and the Trustee by the Holders of at least 25% in
         principal amount of the Outstanding 2020 Debentures a written notice
         specifying such default or breach and requiring it to be remedied and
         stating that such notice is a "Notice of Default" hereunder; or

                  (4) a default under any bonds, debentures, notes or other
         evidences of indebtedness for money borrowed by the Company or a
         Subsidiary or under any mortgages, indentures or instruments under
         which there may be issued or by which there may be secured or evidenced
         any indebtedness for money borrowed by the Company or a Subsidiary,
         whether such indebtedness now exists or shall hereafter be created,
         which indebtedness, individually or in the aggregate, is in excess of
         $25.0 million principal amount (excluding any such indebtedness of any
         Subsidiary other than a Significant Subsidiary, all the indebtedness of
         which Subsidiary is nonrecourse to the Company or any other
         Subsidiary), which default shall constitute a failure to pay any
         portion of the principal of such indebtedness when due and payable
         after the expiration of any applicable grace or cure period with
         respect thereto or shall have resulted in such indebtedness becoming or
         being declared due and payable prior to the date on which it would
         otherwise have become due and payable, without such indebtedness having
         been discharged, or such acceleration having been rescinded or
         annulled, within a period of 10 days after there shall have been given,
         by registered or certified mail, to the Company by the Trustee or to
         the Company and the Trustee by the Holders of at least 25% in principal
         amount of the Outstanding 2020 Debentures a written notice specifying
         such default and requiring the Company to cause such indebtedness to be
         discharged or cause such acceleration to be rescinded or annulled and
         stating that such notice is a "Notice of Default" hereunder; or

                                       20
<PAGE>   24

                  (5) the entry by a court having jurisdiction in the premises
         of (A) a decree or order for relief in respect of the Company or a
         Significant Subsidiary in an involuntary case or proceeding under any
         applicable Federal or State bankruptcy, insolvency, reorganization or
         other similar law or (B) a decree or order adjudging the Company or a
         Significant Subsidiary a bankrupt or insolvent, or approving as
         properly filed a petition seeking reorganization, arrangement,
         adjustment or composition of or in respect of the Company or a
         Significant Subsidiary under any applicable Federal or State law, or
         appointing a custodian, receiver, liquidator, assignee, trustee,
         sequestrator or other similar official of the Company or a Significant
         Subsidiary or of any substantial part of their respective properties,
         or ordering the winding up or liquidation of the affairs of the Company
         or a Significant Subsidiary, and the continuance of any such decree or
         order for relief or any such other decree or order unstayed and in
         effect for a period of 60 consecutive days; or

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

SECTION 208 Unconditional Right of Holders to Receive Principal, Premium and
            Interest.

         Section 508 of the Indenture is hereby amended, subject to Section 201
hereof and with respect to the 2020 Debentures only, by replacing that section
with the following:

                                       21

<PAGE>   25

         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 such Security 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 Repurchase Price on
         the Repurchase Date, or in the case of a Change in Control, to receive
         the Change in Control Purchase Price on the Change in Control 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 209 Reports by Company.

         Section 704 of the Indenture is hereby amended, subject to Section 201
hereof and with respect to the 2020 Debentures only, by adding the following
paragraph thereto:

                  (4) If at any time while any of the Securities are "restricted
         securities" within the meaning of Rule 144, the Company is no longer
         subject to the reporting requirements of Section 13 or 15(d) of the
         Exchange Act, the Company will prepare and will furnish to any Holder,
         any beneficial owner of Securities and any prospective purchaser of
         Securities designated by a Holder or a beneficial owner of Securities,
         promptly upon request, the information required pursuant to Rule
         144A(d)(4) (or any successor thereto) under the Securities Act in
         connection with the offer, sale or transfer of Securities.

SECTION 210 Consolidation, Merger and Sale.

           Section 801 of the Indenture is hereby amended, subject to Section
201 hereof and with respect to the 2020 Debentures only, by inserting "and shall
have provided for conversion rights in accordance with Section 1411" at the end
of Section 801(1).

SECTION 211 Supplemental Indentures Without Consent of Holders.

           Section 901 of the Indenture is hereby amended, subject to Section
201 hereof and with respect to the 2020 Debentures only, by inserting the
following paragraph:

                  (9) to make provision with respect to the conversion rights,
         if any, to Holders of 2020 Debentures pursuant to the requirements of
         Article Fourteen hereof.

                                       22

<PAGE>   26

SECTION 212 Supplemental Indenture with Consent of Holder.

           Section 902 of the Indenture is hereby amended, subject to Section
201 hereof and with respect to the 2020 Debentures only, by inserting ", or (4)
adversely affect the right to convert any 2020 Debenture as provided in Article
Fourteen, or adversely affect the right to require the Company to repurchase the
2020 Debentures as provided in Article Fifteen." at the end of Section 902(3).

SECTION 213 Amendment to Article Ten of the Indenture.

           Article Ten of the Indenture is hereby amended, subject to Section
201 hereof and with respect to the 2020 Debentures only, by adding the following
sections thereto:

         SECTION 1006 Maintenance of Properties.

                  The Company will cause all properties used or useful in the
         conduct of its business or the business of any Subsidiary to be
         maintained and kept in good condition, repair and working order, normal
         wear and tear excepted, and supplied with all necessary equipment and
         will cause to be made all necessary repairs, renewals, replacements,
         betterments and improvements thereof, all as in the judgment of the
         Company may be necessary so that the business carried on in connection
         therewith may be properly and advantageously conducted at all times;
         provided, however, that nothing in this Section 1006 shall prevent the
         Company from discontinuing the operation or maintenance of any of such
         properties, or disposing of any of them, if such discontinuance or
         disposition is, in the judgment of the Company, desirable in the
         conduct of its business or the business of any Subsidiary.

         SECTION 1007 Payment of Taxes and Other Claims.

                  The Company will pay or discharge or cause to be paid or
         discharged, before the same shall become delinquent, (1) all taxes,
         assessments and governmental charges levied or imposed upon the Company
         or any Subsidiary or upon the income, profits or property of the
         Company or any Subsidiary, and (2) all lawful claims for labor,
         materials and supplies which, if unpaid, might by law become a material
         Lien upon the property of the Company or any Subsidiary; provided,
         however, that the Company shall not be required to pay or discharge or
         cause to be paid or discharged any such tax, assessment, charge or
         claim whose amount, applicability or validity is being contested in
         good faith by appropriate proceedings.

                                       23

<PAGE>   27

         SECTION 1008 Waiver of Certain Covenants.

                  The Company may omit in any particular instance to comply with
         any covenant or condition set forth in Sections 1005 to 1010,
         inclusive, if before the time for such compliance the Holders of at
         least a majority in principal amount of the Outstanding 2020 Debentures
         shall, by Act of such Holders, either waive such compliance in such
         instance or generally waive compliance with such covenant or condition,
         but no such waiver shall extend to or affect such covenant or condition
         except to the extent so expressly waived, and, until such waiver shall
         become effective, the obligations of the Company and the duties of the
         Trustee in respect of any such covenant or condition shall remain in
         full force and effect.

         SECTION 1009 Limitation on Liens.

                  The Company shall not create, assume or suffer to exist any
         Lien on any Restricted Property to secure any debt of the Company, any
         Subsidiary or any other Person, or permit any Subsidiary so to do,
         without making effective provision whereby the 2020 Debentures then
         outstanding and having the benefit of this Section shall be secured by
         a Lien equally and ratably with such debt for so long as such debt
         shall be so secured, except that the foregoing shall not prevent the
         Company or any Subsidiary from creating, assuming or suffering to exist
         Liens of the following character:

                  (1) any Lien existing on the Issue Date of the 2020
         Debentures;

                  (2) any Lien existing on Restricted Property owned or leased
         by a corporation at the time it becomes a Subsidiary;

                  (3) any Lien existing on Restricted Property at the time of
         the acquisition thereof by the Company or a Subsidiary;

                  (4) any Lien to secure any debt incurred prior to, at the time
         of, or within 12 months after the acquisition of Restricted Property
         for the purpose of financing all or any part of the purchase price
         thereof and any Lien to the extent that it secures debt which is in
         excess of such purchase price and for the payment of which recourse may
         be had only against such Restricted Property;

                  (5) any Lien to secure any debt incurred prior to, at the time
         of, or within 12 months after the completion of the construction and
         commencement of commercial operation, alteration, repair or improvement
         of Restricted Property for the purpose of financing all or any part of
         the cost thereof and any Lien to the extent that it secures debt which
         is in excess of such cost and for the payment of which recourse may be
         had only against such Restricted Property;

                                       24

<PAGE>   28

                  (6) any Lien securing debt of a Subsidiary owing to the
         Company or to another Subsidiary;

                  (7) any Lien in favor of the United States of America or any
         State thereof or any other country, or any agency, instrumentality of
         political subdivision of any of the foregoing, to secure partial,
         progress, advance or other payments or performance pursuant to the
         provisions of any contract or statute, or any Liens securing industrial
         development, pollution control, or similar revenue bonds;

                  (8) Liens imposed by law, such as mechanics', workmen's,
         repairmen's, materialmen's, carriers', warehousemen's, vendors' or
         other similar Liens arising in the ordinary course of business, or
         governmental (federal, state or municipal) Liens arising out of
         contracts for the sale of products or services by the Company or any
         Subsidiary, or deposits or pledges to obtain the release of any of the
         foregoing;

                  (9) pledges or deposits under workmen's compensation laws or
         similar legislation and Liens of judgments thereunder which are not
         currently dischargeable, or good faith deposits in connection with
         bids, tenders, contracts (other than for the payment of money) or
         leases to which the Company or any Subsidiary is a party, or deposits
         to secure public or statutory obligations of the Company or any
         Subsidiary, or deposits in connection with obtaining or maintaining
         self-insurance or to obtain the benefits of any law, regulation or
         arrangement pertaining to unemployment insurance, old age pensions,
         social security or similar matters, or deposits of cash or obligations
         of the United States of America to secure surety, appeal or customs
         bonds to which the Company or any Subsidiary is a party, or deposits in
         litigation or other proceedings such as, but not limited to,
         interpleader proceedings;

                  (10) Liens created by or resulting from any litigation or
         other proceeding which is being contested in good faith by appropriate
         proceedings, including Liens arising out of judgments or awards against
         the Company or any Subsidiary with respect to which the Company or such
         Subsidiary is in good faith prosecuting an appeal or proceedings for
         review; or Liens incurred by the Company or any Subsidiary for the
         purpose of obtaining a stay or discharge in the course of any
         litigation or other proceeding to which the Company or such Subsidiary
         is a party;

                  (11) Liens for taxes or assessments or governmental charges or
         levies not yet due or delinquent, or which can thereafter be paid
         without penalty, or which are being contested in good faith by
         appropriate proceedings;

                  (12) any extension, renewal or replacement (or successive
         extensions, renewals or replacements) in whole or in part of any Lien
         referred to in

                                       25

<PAGE>   29

         clauses (1) through (11) above, so long as the principal amount of the
         debt secured thereby does not exceed the principal amount of debt so
         secured at the time of the extension, renewal or replacement (except
         that, where an additional principal amount of debt is incurred to
         provide funds for the completion of a specific project, the additional
         principal amount, and any related financing costs, may be secured by
         the Lien as well) and the Lien is limited to the same property subject
         to the Lien so extended, renewed or replaced (plus improvements on the
         property); and

                  (13) any Lien not permitted by clauses (1) through (12) above
         securing debt that, together with the aggregate outstanding principal
         amount of all other debt of the Company and its Subsidiaries secured by
         Liens which would otherwise be prohibited by the foregoing restrictions
         and the aggregate Value of existing Sale and Leaseback Transactions
         which would be subject to the restrictions of Section 1010 but for this
         clause (13), does not at any time exceed 10% of Consolidated Net
         Tangible Assets.

         SECTION 1010 Limitation on Sale And Leasebacks.

                  The Company shall not enter into any Sale and Leaseback
         Transaction covering any Restricted Property, nor permit any Subsidiary
         so to do, unless either:

                  (1) the Company or such Subsidiary would be entitled to incur
         debt, in a principal amount at least equal to the Value of such Sale
         and Leaseback Transaction, which is secured by Liens on the property to
         be leased (without equally and ratably securing the Outstanding 2020
         Debentures) because such Liens would be of such character that no
         violation of the provisions of Section 1009 would result, or

                  (2) the Company during the six months immediately following
         the effective date of such Sale and Leaseback Transaction causes to be
         applied to (A) the acquisition of Restricted Property or (B) the
         voluntary retirement of Funded Debt (whether by redemption, defeasance,
         repurchase, or otherwise) an amount equal to the Value of such Sale and
         Leaseback Transaction.

SECTION 214 Maintenance of Office or Agency.

         The first paragraph of Section 1002 of the Indenture is hereby amended,
subject to Section 201 hereof and with respect to the 2020 Debentures only, by
changing the first sentence thereof to read in its entirety as follows:

                  The Company will maintain in each Place of Payment for the
         2020 Debentures an office or agency where the 2020 Debentures may be
         presented or

                                       26

<PAGE>   30

         surrendered for payment, where the 2020 Debentures may be surrendered
         for registration of transfer or exchange, where the 2020 Debentures may
         be surrendered for conversion and where notices and demands to or upon
         the Company in respect of the 2020 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.

SECTION 215 Redemption.

         Article Eleven of the Indenture is hereby amended, subject to Section
201 hereof and with respect to the 2020 Debentures only, by inserting the
following section in its entirety:

         SECTION 1109 Conversion Arrangement on Call for Redemption.

                  In connection with 2020 Debentures, the Company may arrange
         for the purchase and conversion of any 2020 Debentures called for
         redemption by an agreement with one or more investment bankers or other
         purchasers to purchase such 2020 Debentures by paying to a Paying Agent
         (other than the Company or any of its Affiliates) in trust for the
         Holders, on or before 11:00 A.M. New York City time on the Redemption
         Date, an amount that, together with any amounts deposited with such
         Paying Agent by the Company for the redemption of such 2020 Debentures,
         is not less than the Redemption Price of such 2020 Debentures.
         Notwithstanding anything to the contrary contained in this Article
         Eleven, the obligation of the Company to pay the Redemption Price of
         such 2020 Debentures, including interest, if any, shall be deemed to be
         satisfied and discharged to the extent such amount is so paid by such
         purchasers; provided, however, that nothing in this Section 1109 shall
         relieve the Company of its obligation to pay the Redemption Price on
         2020 Debentures called for redemption. If such an agreement is entered
         into, any 2020 Debentures called for redemption and not surrendered for
         conversion by the Holders thereof prior to the relevant Redemption Date
         may, at the option of the Company upon written notice to the Trustee,
         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 as of 11:00 A.M. New York City time on the
         Redemption Date, subject to payment of the above amount as aforesaid.
         The Paying Agent shall hold and pay to the Holders whose 2020
         Debentures are selected for redemption any such amount paid to it for
         purchase in the same manner as it would money deposited

                                       27

<PAGE>   31
         with it by the Company for the redemption of 2020 Debentures. Without
         the Paying Agent's prior written consent, no arrangement between the
         Company and such purchasers for the purchase and conversion of any 2020
         Debentures 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 2020 Debentures between the Company
         and such purchasers, including the costs and expenses incurred by the
         Paying Agent in the defense of any claim or liability reasonably
         incurred without negligence or bad faith on its part arising out of or
         in connection with the exercise or performance of any of its powers,
         duties, responsibilities or obligations under this Indenture, in
         accordance with the indemnity provisions applicable to the Trustee set
         forth herein.

SECTION 216 Conversion, Tax Event, Repurchase.

         The Indenture is hereby amended, subject to Section 201 hereof and with
respect to the 2020 Debentures only, by adding the following Articles Fourteen,
Fifteen, Sixteen and Seventeen to the Indenture:

                                ARTICLE FOURTEEN

                                   CONVERSION

         SECTION 1401 Conversion Privilege.

                  2020 Debentures shall be convertible in accordance with their
         terms and in accordance with this Article.

                  A Holder of a 2020 Debenture may convert the Principal Amount
         of such 2020 Debenture (or any portion thereof equal to a Principal
         Amount of $1,000 or any integral multiple of a Principal Amount of
         $1,000 in excess thereof) into Common Stock at any time prior to the
         close of business on the date specified in the 2020 Debentures, at the
         Conversion Rate then in effect. In case a 2020 Debenture or portion
         thereof is called for redemption pursuant to Article Eleven, such
         conversion right shall terminate at the close of business on the
         Business Day immediately preceding the Redemption Date for such 2020
         Debenture or such earlier date as the Holder presents such 2020
         Debenture for redemption (unless the Company shall default in making
         the redemption payment when due, in which case the conversion right
         shall terminate at the close of business on the date such default is
         cured and such 2020 Debenture is redeemed). The number of shares of
         Common Stock issuable upon conversion of a 2020 Debenture per $1,000 of

                                       28
<PAGE>   32

         Principal Amount thereof (the "Conversion Rate") shall be that set
         forth under "Conversion" in the 2020 Debentures, subject to adjustment
         as herein set forth. Provisions of this Indenture that apply to
         conversion of all of a 2020 Debenture also apply to conversion of a
         portion of a 2020 Debenture.

                  A 2020 Debenture in respect of which a Holder has delivered a
         Repurchase Notice or Change in Control Purchase Notice exercising the
         option of such Holder to require the Company to purchase such 2020
         Debenture, may be converted only if such notice of exercise is
         withdrawn in accordance with the terms of this Indenture. A Holder of
         2020 Debentures is not entitled to any rights of a holder of Common
         Stock until such Holder has converted its 2020 Debentures to Common
         Stock, and only to the extent such 2020 Debentures are deemed to have
         been converted into Common Stock pursuant to this Article Fourteen.

         SECTION 1402 Conversion Procedure.

                  To convert a 2020 Debenture, a Holder must (a) complete and
         manually sign the conversion notice on the back of the 2020 Debenture
         and deliver such notice to a Conversion Agent, (b) surrender the 2020
         Debenture to a Conversion Agent, (c) furnish appropriate endorsements
         and transfer documents if required by the Security Registrar or a
         Conversion Agent, and (d) pay any transfer or similar tax, if required.
         The date on which the Holder satisfies all of those requirements is the
         "Conversion Date" As soon as practicable after the Conversion Date, the
         Company shall deliver to the Holder through a Conversion Agent a
         certificate for the number of whole shares of Common Stock issuable
         upon the conversion and cash in lieu of any fractional shares pursuant
         to Section 1403. Anything herein to the contrary notwithstanding, in
         the case of Global Securities, conversion notices may be delivered and
         such 2020 Debentures may be surrendered for conversion in accordance
         with the applicable procedures of the Depositary as in effect from time
         to time. The Person in whose name the Common Stock certificate is
         registered shall be deemed to be a shareholder of record on the
         Conversion Date; provided, however, that no surrender of a 2020
         Debenture 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;
         provided further, however, that such conversion shall be at the
         Conversion Rate in effect on the date that such 2020 Debenture shall
         have been surrendered for conversion, as if the stock transfer books of
         the Company had not been closed.

                                       29
<PAGE>   33

         Upon conversion of a 2020 Debenture, such Person shall no longer be a
         Holder of such 2020 Debenture.

                  No payment or adjustment 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 2020 Debenture,
         that portion of accrued Original Issue Discount (and interest, if the
         Company has exercised its option provided for in Section 1601)
         attributable to the period from the Issue Date (or, in the case of
         interest, if the Company has exercised the option provided for in
         Section 1601, the later of (x) the date of such exercise and (y) the
         date on which interest was last paid) of the 2020 Debenture through the
         Conversion Date with respect to the converted 2020 Debenture shall not
         be cancelled, 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 2020 Debenture being converted pursuant to
         the provisions hereof; and the fair market value of such shares of
         Common Stock (together with any such cash payment in lieu of fractional
         shares) shall be treated as issued, to the extent thereof, first in
         exchange for Original Issue Discount (and interest, if the Company has
         exercised its option provided for in Section 1601) accrued through the
         Conversion Date, and the balance, if any, of such fair market value of
         such Common Stock (and any such cash payment) shall be treated as
         issued in exchange for the Issue Price of the 2020 Debenture being
         converted pursuant to the provisions hereof.

                  If a Holder converts more than one 2020 Debenture at the same
         time, the number of shares of Common Stock issuable upon the conversion
         shall be based on the aggregate Principal Amount of 2020 Debentures
         converted.

                  Upon surrender of a 2020 Debenture that is converted in part,
         the Company shall execute, and the Trustee shall authenticate and
         deliver to the Holder, a new 2020 Debenture equal in Principal Amount
         to the Principal Amount of the unconverted portion of the 2020
         Debenture surrendered.

                  Where the Company has exercised its option under Section 1701,
         2020 Debentures or portions thereof surrendered for conversion during
         the period from the close of business on any Regular Record Date
         immediately preceding any Interest Payment Date to the opening of
         business on such Interest Payment Date shall (unless such 2020
         Debentures or portions thereof have been called for redemption on a
         Redemption Date within such period) be accompanied by payment to the
         Company or its order, in New York Clearing House funds or other funds
         acceptable to the Company, of an amount equal to the interest payable
         on such Interest Payment Date on the principal amount of 2020
         Debentures or portions thereof being surrendered for conversion.

                                       30
<PAGE>   34

         SECTION 1403 Fractional Shares.

                  The Company will not issue fractional shares of Common Stock
         upon conversion of 2020 Debentures. In lieu thereof, the Company will
         pay an amount in cash based upon the closing price of the Common Stock
         on the Trading Day immediately prior to the Conversion Date.

         SECTION 1404 Taxes on Conversion.

                  If a Holder converts a 2020 Debenture, the Company shall pay
         any documentary, stamp or similar issue or transfer tax due on the
         issue of shares of Common Stock upon such 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 certificate 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 regulation.

         SECTION 1405 Company to Provide Common Stock.

                  The Company shall, prior to issuance of any 2020 Debentures
         under this Article Fourteen, 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
         all 2020 Debentures Outstanding into shares of Common Stock. All shares
         of Common Stock delivered upon conversion of the 2020 Debentures shall
         be newly issued shares, shall be duly authorized, validly issued, fully
         paid and nonassessable and shall be free from preemptive rights and
         free of any Lien or adverse claim.

                  The Company will endeavor promptly to comply with all federal
         and state securities laws regulating the registration of the offer and
         delivery of shares of Common Stock to a converting Holder upon
         conversion of 2020 Debentures, if any, and will list or cause to have
         quoted such shares of Common Stock on each national securities exchange
         or on the Nasdaq National Market or other over-the-counter market or
         such other market on which the Common Stock are then listed or quoted.

         SECTION 1406 Adjustment of Conversion Rate.

                  The Conversion Rate shall be adjusted from time to time by the
         Company as follows:

                                       31
<PAGE>   35

                  (a) In case the Company shall (i) pay a dividend on its Common
         Stock in shares of Common Stock, (ii) make a distribution on its Common
         Stock in shares of Common Stock, (iii) subdivide its outstanding Common
         Stock into a greater number of shares, or (iv) combine its outstanding
         Common Stock into a smaller number of shares, the Conversion Rate in
         effect immediately prior thereto shall be adjusted so that the Holder
         of any 2020 Debenture thereafter surrendered for conversion shall be
         entitled to receive that number of shares of Common Stock which it
         would have owned had such 2020 Debenture been converted immediately
         prior to the happening of such event. An adjustment made pursuant to
         this subsection (a) shall become effective immediately after the
         record date in the case of a dividend or distribution and shall become
         effective immediately after the effective date in the case of
         subdivision or combination.

                  (b) In case the Company shall issue rights or warrants to all
         or substantially all holders of its Common Stock entitling them (for a
         period commencing no earlier than the record date described below and
         expiring not more than 60 days after such record date) to subscribe for
         or purchase shares of Common Stock (or securities convertible into
         Common Stock) at a price per share (or having a conversion price per
         share) less than the current market price per share of Common Stock (as
         determined in accordance with subsection (e) of this Section 1406) on
         the record date for the determination of shareholders 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 rate determined by multiplying the Conversion Rate in effect
         immediately prior to such record date by a fraction of which the
         numerator shall be the number of shares of Common Stock outstanding on
         such record date plus the number of additional shares of Common Stock
         offered (or into which the convertible securities so offered are
         convertible), and of which the denominator shall be the number of
         shares of Common Stock outstanding on such record date plus the number
         of shares which the aggregate offering price of the total number of
         shares of Common Stock so offered (or the aggregate conversion price of
         the convertible securities so offered, which shall be determined
         by multiplying the number of shares of Common Stock issuable upon
         conversion of such convertible securities by the conversion price per
         share of Common Stock pursuant to the terms of such convertible
         securities) would purchase at the current market price per share (as
         determined in accordance with subsection (e) of this Section 1406) of
         Common Stock on such record date. Such adjustment shall be made
         successively whenever any such rights or warrants are issued, and shall
         become effective immediately after such record date. If at the end of
         the period during which such rights or warrants are exercisable not all
         rights or warrants shall have been exercised, the adjusted Conversion
         Rate shall be immediately readjusted to what it would have been based
         upon the number of additional shares of Common Stock actually issued
         (or the number of shares of

                                       32
<PAGE>   36

         Common Stock issuable upon conversion of convertible securities
         actually issued).

                  (c) In case the Company shall distribute to all or
         substantially all holders of its Common Stock any shares of capital
         stock (other than dividends or distributions of Common Stock on Common
         Stock to which Section 1406(a) applies) of the Company, evidences of
         indebtedness or other assets (including securities of any Person other
         than the Company, but excluding all-cash distributions or any rights or
         warrants referred to in 1406(b)), then in each such case the Conversion
         Rate shall be adjusted so that the same shall equal the rate determined
         by multiplying the current Conversion Rate by a fraction of which the
         numerator shall be the current market price per share (as determined in
         accordance with subsection (e) of this Section 1406) of the Common
         Stock on the record date mentioned below, and of which the denominator
         shall be the current market price per share (as determined in
         accordance with subsection (e) of this Section 1406) of the Common
         Stock on such record date less the fair market value on such record
         date (as determined by the Board of Directors, whose determination
         shall be conclusive evidence of such fair market value and which shall
         be evidenced by an Officers' Certificate delivered to the Trustee) of
         the portion of the capital stock, evidences of indebtedness or other
         non-cash assets so distributed or of such rights or warrants applicable
         to one share of Common Stock (determined on the basis of the number of
         shares of Common Stock outstanding on the record date). Such adjustment
         shall be made successively whenever any such distribution is made and
         shall become effective immediately after the record date for the
         determination of shareholders entitled to receive such distribution.

                  In the event that the Company implements a shareholder rights
         plan, such rights plan shall provide, subject to customary exceptions
         and limitations, that upon conversion of the 2020 Debentures the
         Holders will receive, in addition to the Common Stock issuable upon
         such conversion, the rights issued under such rights plan
         (notwithstanding the occurrence of an event causing such rights to
         separate from the Common Stock at or prior to the time of conversion).
         Any distribution of rights or warrants pursuant to a shareholder rights
         plan complying with the requirements set forth in the immediately
         preceding sentence of this paragraph shall not constitute a
         distribution of rights or warrants for the purposes of this Section
         1406(c).

                  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

                                       33
<PAGE>   37

         Common Stock, shall be deemed not to have been distributed for purposes
         of this Section 1406(c) (and no adjustment to the Conversion Rate under
         this Section 1406(c) will be required) until the occurrence of the
         earliest Trigger Event. If such right or warrant is subject to
         subsequent events, upon the occurrence of which such right or warrant
         shall become exercisable to purchase different securities, evidences of
         indebtedness or other assets or entitle the holder to purchase a
         different number or amount of the foregoing or to purchase any of the
         foregoing at a different purchase price, then the occurrence of each
         such event shall be deemed to be the date of issuance and record date
         with respect to a new right or warrant (and a termination or expiration
         of the existing right or warrant without exercise by the holder
         thereof). In addition, in the event of any distribution (or deemed
         distribution) of rights or warrants, or any Trigger Event or other
         event (of the type described in the preceding sentence) with respect
         thereto, that resulted in an adjustment to the Conversion Rate under
         this Section 1406(c), (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 such rights or warrants all of
         which shall have expired or been terminated without exercise, the
         Conversion Rate shall be readjusted as if such rights and warrants had
         never been issued.

                  (d) (1) In case the Company shall, by dividend or otherwise,
         at any time distribute (a "Triggering Distribution") to all or
         substantially all holders of its Common Stock all-cash distributions in
         an aggregate amount that, together with the aggregate amount of (A) any
         cash and the fair market value (as determined by the Board of
         Directors, whose determination shall be conclusive evidence thereof and
         which shall be evidenced by an Officers' Certificate delivered to the
         Trustee) of any other consideration payable in respect of any tender
         offer by the Company or a Subsidiary of the Company for Common Stock
         consummated within the 12 months preceding the date of payment of the
         Triggering Distribution and in respect of which no Conversion Rate
         adjustment pursuant to this Section 1406 has been made and (B) all
         other cash distributions to all or substantially all holders of its
         Common Stock made within the 12 months preceding the date of payment of
         the Triggering Distribution and in respect of which no Conversion Rate
         adjustment pursuant to this Section 1406 has been made, exceeds an
         amount equal to 12.5% of the product of the current market price per
         share of Common Stock (as determined in accordance with subsection (e)
         of this Section 1406) on the Business Day (the "Determination
         Date") immediately preceding the day on which such Triggering
         Distribution is declared by the Company multiplied by the

                                       34
<PAGE>   38

         number of shares of Common Stock outstanding on the Determination Date
         (excluding shares held in the treasury of the Company), the Conversion
         Rate shall be increased so that the same shall equal the rate
         determined by multiplying such Conversion Rate in effect immediately
         prior to the Determination Date by a fraction of which the numerator
         shall be such current market price per share of Common Stock (as
         determined in accordance with subsection (e) of this Section 1406) on
         the Determination Date, and the denominator shall be the current market
         price per Ordinary Share (as determined in accordance with subsection
         (e) of this Section 1406) on the Determination Date less the sum of the
         aggregate amount of cash and the aggregate fair market value
         (determined as aforesaid) of any such other consideration so
         distributed, paid or payable within such 12 months (including, without
         limitation, the Triggering Distribution) applicable to one share of
         Common Stock (determined on the basis of the number of shares of Common
         Stock outstanding on the Determination Date), such increase to become
         effective immediately prior to the opening of business on the day
         following the date on which the Triggering Distribution is paid.

                  (2) In case any tender offer made by the Company or any of its
         Subsidiaries for Common Stock shall expire and such tender offer (as
         amended upon the expiration thereof) shall involve the payment of
         aggregate consideration in an amount (determined as the sum of the
         aggregate amount of cash consideration and the aggregate fair market
         value (as determined by the Board of Directors, whose determination
         shall be conclusive evidence thereof and which shall be evidenced by an
         Officers' Certificate delivered to the Trustee thereof) of any other
         consideration) that, together with the aggregate amount of (A) any cash
         and the fair market value (as determined by the Board of Directors,
         whose determination shall be conclusive evidence thereof and which
         shall be evidenced by an Officers' Certificate delivered to the
         Trustee) of any other consideration payable in respect of any other
         tender offers by the Company or any Subsidiary of the Company for
         Common Stock consummated within the 12 months preceding the date of the
         Expiration Date (as defined below) and in respect of which no
         Conversion Rate adjustment pursuant to this Section 1406 has been made
         and (B) all cash distributions to all or substantially all holders of
         its Common Stock made within the 12 months preceding the Expiration
         Date and in respect of which no Conversion Rate adjustment pursuant to
         this Section 1406 has been made, exceeds an amount equal to 12.5% of
         the product of the current market price per share of Common Stock (as
         determined in accordance with subsection (e) of this Section 1406) as
         of the last date (the "Expiration Date") tenders could have been made
         pursuant to such tender offer (as it may be amended) (the last time at
         which such tenders could have been made on the Expiration Date is
         hereinafter sometimes called the "Expiration Time") multiplied by the
         number of shares of Common Stock outstanding (including tendered shares
         but excluding any shares held in the treasury of the Company) at the
         Expiration

                                       35
<PAGE>   39

         Time, then, immediately prior to the opening of business on the day
         after the Expiration Date, the Conversion Rate shall be increased so
         that the same shall equal the rate determined by multiplying the
         Conversion Rate in effect immediately prior to close of business on the
         Expiration Date by a fraction of which the numerator shall be the sum
         of (x) the aggregate consideration (determined as aforesaid) payable to
         stockholders based on the acceptance (up to any maximum specified in
         the terms of the tender offer) of all shares validly tendered and not
         withdrawn as of the Expiration Time (the shares deemed so accepted, up
         to any such maximum, being referred to as the "Purchased Shares") and
         (y) the product of the number of shares of Common Stock outstanding
         (less any Purchased Shares and excluding any shares held in the
         treasury of the Company) at the Expiration Time and the current market
         price per share of Common Stock (as determined in accordance with
         subsection (e) of this Section 1406) on the Trading Day next succeeding
         the Expiration Date, and the denominator shall be the product of the
         number of shares of Common Stock outstanding (including tendered shares
         but excluding any shares held in the treasury of the Company) at the
         Expiration Time multiplied by the current market price per share of
         Common Stock (as determined in accordance with subsection (e) of this
         Section 1406) on the Trading Day next succeeding the Expiration Date,
         such increase to become effective immediately prior to the opening of
         business on the day following the Expiration Date. In the event that
         the Company is obligated to purchase shares pursuant to any such tender
         offer, but the Company is permanently prevented by applicable law from
         effecting any or all such purchases or any or all such purchases are
         rescinded, the Conversion Rate shall again be adjusted to be the
         Conversion Rate which would have been in effect based upon the number
         of shares actually purchased. If the application of this Section
         1406(d)(2) to any tender offer would result in a decrease in the
         Conversion Rate, no adjustment shall be made for such tender offer
         under this Section 1406(d)(2).

                  (3) For purposes of this Section 1406(d), the term "tender
         offer" shall mean and include both tender offers and exchange offers,
         all references to "purchases" of shares in tender offers (and all
         similar references) shall mean and include both the purchase of shares
         in tender offers and the acquisition of shares pursuant to exchange
         offers, and all references to "tendered shares" (and all similar
         references) shall mean and include shares tendered in both tender
         offers and exchange offers.

                  (e) For the purpose of any computation under subsections (b),
         (c) and (d) of this Section 1406, the current market price per share of
         Common Stock on any date shall be deemed to be the average of the daily
         closing prices for the 30 consecutive Trading Days commencing 45
         Trading Days before (i) the Determination Date or the Expiration Date,
         as the case may be, with respect to

                                       36
<PAGE>   40

         distributions or tender offers under subsection (d) of this
         Section 1406 or (ii) the record date with respect to distributions,
         issuances or other events requiring such computation under
         subsection (b) or (c) of this Section 1406. The closing price for each
         day shall be the last reported sales price or, in case no such reported
         sale takes place on such date, the average of the reported closing bid
         and asked prices in either case on the New York Stock Exchange (the
         "NYSE") or, if the Common Stock is not listed or admitted to trading on
         the NYSE, on the principal national securities exchange on which the
         Common Stock are listed or admitted to trading or, if not listed or
         admitted to trading on any national securities exchange, the last
         reported sales price of the Common Stock as quoted on NASDAQ (the term
         "NASDAQ" shall include, without limitation, the Nasdaq National Market)
         or, in case no reported sales takes place, the average of the closing
         bid and asked prices as quoted on NASDAQ or any comparable system or,
         if the Common Stock is not quoted on NASDAQ or any comparable system,
         the closing sales price or, in case no reported sale takes place, the
         average of the closing bid and asked prices, as furnished by any two
         members of the National Association of Securities Dealers, Inc.
         selected from time to time by the Company for that purpose. If no such
         prices are available, the current market price per share shall be the
         fair value of an Ordinary Share as determined by the Board of Directors
         (which shall be evidenced by an Officers' Certificate delivered to the
         Trustee).

                  (f) In any case in which this Section 1406 shall require that
         an adjustment be made following a record date or a Determination Date
         or Expiration Date, as the case may be, established for purposes of
         this Section 1406, the Company may elect to defer (but only until five
         Business Days following the filing by the Company with the Trustee of
         the certificate described in Section 1409) issuing to the Holder of any
         2020 Debenture converted after such record date or Determination Date
         or Expiration Date the shares of Common Stock and other capital stock
         of the Company issuable upon such conversion over and above the shares
         of Common Stock and other capital stock of the Company issuable upon
         such conversion only on the basis of the Conversion Rate prior to
         adjustment; and, in lieu of the shares the issuance of which is so
         deferred, the Company shall issue or cause its transfer agents to issue
         due bills or other appropriate evidence prepared by the Company of the
         right to receive such shares. If any distribution in respect of which
         an adjustment to the Conversion Rate is required to be made as of the
         record date or Determination Date or Expiration Date therefor is not
         thereafter made or paid by the Company for any reason, the Conversion
         Rate shall be readjusted to the Conversion Rate which would then be in
         effect if such record date had not been fixed or such effective date or
         Determination Date or Expiration Date had not occurred.

                                       37
<PAGE>   41

         SECTION 1407 No Adjustment.

                  No adjustment in the Conversion Rate shall be required unless
         the adjustment would require an increase or decrease of at least 1% in
         the Conversion Rate as last adjusted; provided, however, that any
         adjustments which by reason of this Section 1407 are not required to be
         made shall be carried forward and taken into account in any subsequent
         adjustment. All calculations under this Article Fourteen shall be made
         to the nearest cent or to the nearest 1/1000th of a share, as the case
         may be.

                  No adjustment need be made for issuances of Common Stock
         pursuant to a Company plan for reinvestment of dividends or interest or
         for a change in the par value or a change to no par value of the Common
         Stock.

                  To the extent that the 2020 Debentures become convertible into
         the right to receive cash, no adjustment need be made thereafter as to
         the cash. Interest will not accrue on the cash.

         SECTION 1408 Adjustment for Tax Purposes.

                  The Company shall be entitled to make such adjustments in the
         Conversion Rate, in addition to those required by Section 1406, as it
         in its discretion shall determine to be advisable in order that any
         stock dividends, subdivisions of shares, distributions of rights to
         purchase stock or securities or distributions of securities convertible
         into or exchangeable for stock hereafter made by the Company to its
         stockholders shall not be taxable.

         SECTION 1409 Notice of Adjustment.

                  Whenever the Conversion Rate is adjusted, the Company shall
         promptly mail to Holders a notice of the adjustment and file with the
         Trustee an Officers' Certificate specifying the adjusted Conversion
         Rate, and briefly stating the facts requiring the adjustment and the
         manner of computing it.

         SECTION 1410 Notice of Certain Transactions.

                  In the event that:

                  (1) the Company takes any action which would require an
         adjustment in the Conversion Rate,

                  (2) the Company takes any action that requires a supplemental
         indenture pursuant to Section 1411, or

                                       38
<PAGE>   42

                  (3) there is a dissolution or liquidation of the Company,

         the Company shall mail to Holders and file with the Trustee a notice
         stating the proposed record or effective date, as the case may be. The
         Company shall mail the notice at least fifteen days before such date.
         Failure to mail such notice or any defect therein shall not affect the
         validity of any transaction referred to in clause (1), (2) or (3) of
         this Section 1410.

         SECTION 1411 Effect of Reclassification, Consolidation, Merger or Sale
                      on Conversion Privilege.

                  If any of the following shall occur, namely: (a) any
         reclassification or change of shares of Common Stock issuable upon
         conversion of the 2020 Debentures (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); (b) any consolidation or
         merger in which the Company is a party consolidating with another
         entity or merging with or into another entity other than a merger in
         which the Company is the continuing corporation and which does not
         result in any reclassification of, or change (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) in,
         Outstanding shares of Common Stock; or (c) any sale or conveyance of
         all or substantially all of the property and assets of the Company to
         any Person, then the Company, or such successor, purchasing or
         transferee corporation, as the case may be, shall, as a condition
         precedent to such reclassification, change, consolidation, merger, sale
         or conveyance, execute and deliver to the Trustee a supplemental
         indenture providing that the Holder of each 2020 Debenture then
         Outstanding shall have the right to convert such 2020 Debenture into
         the kind and amount of shares of stock and other securities and
         property (including cash) receivable upon such reclassification,
         change, consolidation, merger, sale or conveyance by a holder of the
         number of shares of Common Stock deliverable upon conversion of such
         2020 Debenture immediately prior to such reclassification, change,
         consolidation, merger, sale or conveyance. Such supplemental indenture
         shall provide for adjustments of the Conversion Rate which shall be as
         nearly equivalent as may be practicable to the adjustments of the
         Conversion Rate provided for in this Article Fourteen. If, in the case
         of any such consolidation, merger, sale or conveyance, the stock or
         other securities and property (including cash) receivable thereupon by
         a holder of Common Stock include shares of stock or other securities
         and property of a Person other than the successor, purchasing or
         transferee corporation, as the case may be, in such consolidation,
         merger, sale or conveyance, then such supplemental indenture shall also
         be executed by such other Person and shall contain such additional
         provisions to protect the interests of the Holders of the 2020
         Debentures as the Board of Directors shall reasonably consider
         necessary by reason of the foregoing. The

                                       39
<PAGE>   43

         provisions of this Section 1411 shall similarly apply to successive
         reclassifications, changes, consolidations, mergers, sales or
         conveyances.

                  In the event the Company shall execute a supplemental
         indenture pursuant to this Section 1411, the Company shall promptly
         file with the Trustee (x) an Officers' Certificate briefly stating the
         reasons therefor, the kind or amount of shares of stock or other
         securities or property (including cash) receivable by Holders of the
         2020 Debentures upon the conversion of their 2020 Debentures after any
         such reclassification, change, consolidation, merger, sale or
         conveyance, any adjustment to be made with respect thereto and that all
         conditions precedent have been complied with and (y) an Opinion of
         Counsel that all conditions precedent have been complied with, and
         shall promptly mail notice thereof to all Holders.

         SECTION 1412 Trustee's Disclaimer.

                  The Trustee shall have no duty to determine when an adjustment
         under this Article Fourteen should be made, how it should be made or
         what such adjustment should be, but may accept as conclusive evidence
         of that fact or the correctness of any such adjustment, and shall be
         protected in relying upon, an Officers' Certificate including the
         Officers' Certificate with respect thereto which the Company is
         obligated to file with the Trustee pursuant to Section 1409. The
         Trustee makes no representation as to the validity or value of any
         securities or assets issued upon conversion of 2020 Debentures, and the
         Trustee shall not be responsible for the Company's failure to comply
         with any provisions of this Article Fourteen.

                  The Trustee shall not be under any responsibility to determine
         the correctness of any provisions contained in any supplemental
         indenture executed pursuant to Section 1411, but may accept as
         conclusive evidence of the correctness thereof, and shall be fully
         protected in relying upon, the Officers' Certificate with respect
         thereto which the Company is obligated to file with the Trustee
         pursuant to Section 1411.

         SECTION 1413 Voluntary Increase.

                  The Company from time to time may increase the Conversion Rate
         by any amount for any period of time if the period is at least 20 days
         or such longer period as may be required by law and if the increase is
         irrevocable during the period.

                                       40
<PAGE>   44

                                 ARTICLE FIFTEEN

                REPURCHASE OF SECURITIES AT OPTION OF THE HOLDER

         SECTION 1501 General.

                  The Company may be required to repurchase 2020 Debentures in
         accordance with their terms and in accordance with this Article.

                  2020 Debentures shall be purchased by the Company under the
         paragraph "Repurchase by the Company at the Option of the Holder" of
         the 2020 Debentures on June 6, 2005, June 6, 2010 and June 6, 2015
         (each, a "Repurchase Date"), at the repurchase price specified therein
         (each, a "Repurchase 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 "Repurchase Notice") at any time from the opening
         of business on the date that is 20 Business Days prior to a Repurchase
         Date until the close of business on such Repurchase Date stating:

                           (A) the certificate number of the 2020 Debenture
                  which the Holder will deliver to be repurchased,

                           (B) the portion of the Principal Amount of the 2020
                  Debenture which the Holder will deliver to be repurchased,
                  which portion must be $1,000 or an integral multiple thereof,

                           (C) that such 2020 Debenture shall be purchased as of
                  the Repurchase Date pursuant to the terms and conditions
                  specified under the paragraph "Repurchase by the Company at
                  the Option of the Holder" of the 2020 Debentures and in this
                  Indenture,

                           (D) in the event that the Company elects, pursuant to
                  Section 1502 hereof, to pay the Repurchase Price to be paid as
                  of such Repurchase Date, in whole or in part, in Common Stock
                  but such portion of the Repurchase Price shall ultimately be
                  payable to such Holder entirely in cash because any of the
                  conditions to payment of the Repurchase Price in Common Stock
                  is not satisfied prior to the close of business on such
                  Repurchase Date, as set forth in Section 1503 hereof, whether
                  such Holder elects (i) to withdraw such Repurchase Notice as
                  to some or all of the 2020 Debentures to which such Repurchase
                  Notice relates (stating the Principal Amount at Maturity and
                  certificate numbers of the 2020 Debentures as to which such
                  withdrawal shall relate), or (ii) to receive cash in respect
                  of the entire Repurchase Price for all 2020 Debentures (or
                  portions thereof) to which such Repurchase Price relates, and

                                       41
<PAGE>   45

                  (2) delivery of such 2020 Debenture to the Paying Agent prior
         to, on or after the Repurchase 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 Repurchase Price therefor;
         provided, however, that such Repurchase Price shall be so paid pursuant
         to this Article Fifteen only if the 2020 Debenture so delivered to the
         Paying Agent shall conform in all respects to the description thereof
         in the related Repurchase Notice.

                  If a Holder, in such Holder's Repurchase Notice and in any
         written notice of withdrawal delivered by such Holder pursuant to the
         terms of Section 1509 hereof, fails to indicate such Holder's choice
         with respect to the election set forth in clause (D) of Section
         1501(1), such Holder shall be deemed to have elected to receive cash in
         respect of the Repurchase Price for all 2020 Debentures subject to the
         Repurchase Notice in the circumstances set forth in such clause (D).

                  The Company shall purchase from the Holder thereof, pursuant
         to this Article Fifteen, a portion of a 2020 Debenture 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
         2020 Debenture also apply to the purchase of such portion of such 2020
         Debenture.

                  Any purchase by the Company contemplated pursuant to the
         provisions of this Article Fifteen shall be consummated by the delivery
         of the consideration to be received by the Holder promptly following
         the later of the Repurchase Date and the time of delivery of the 2020
         Debenture.

                  Notwithstanding anything herein to the contrary, any Holder
         delivering to the Paying Agent the Repurchase Notice contemplated by
         this Section 1501 shall have the right to withdraw such Repurchase
         Notice at any time prior to the close of business on the Repurchase
         Date by delivery of a written notice of withdrawal to the Paying Agent
         in accordance with Section 1509.

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

         SECTION 1502 The Company's Right to Elect Manner of Payment of
                      Repurchase Price.

                  (a) The Repurchase Price of 2020 Debentures in respect of
         which a Repurchase Notice pursuant to Section 1501 has been given, or a
         specified percentage thereof will be paid by the Company, at the
         election of the Company, with cash or Common Stock or in any
         combination of cash and Common Stock, subject to the conditions set
         forth in Section 1502 and 1503 hereof. The Company

                                       42
<PAGE>   46
         shall designate, in the Company Notice delivered pursuant to Section
         1505 hereof, whether the Company will purchase the 2020 Debentures for
         cash or Common Stock, or, if a combination thereof, the percentages of
         the Repurchase Price of 2020 Debentures in respect of which it will pay
         in cash and Common Stock; provided, however, that the Company will pay
         cash for fractional interests in Common Stock. For purposes of
         determining the existence of potential fractional interests, all 2020
         Debentures 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 2020 Debentures are purchased pursuant to
         this Article Fifteen shall receive the same percentage of cash or
         Common Stock in payment of the Repurchase Price for such 2020
         Debentures, except (i) as provided in Section 1504 with regard to the
         payment of cash in lieu of fractional Common Stock and (ii) in the
         event that the Company is unable to purchase the 2020 Debentures of a
         Holder or Holders for Common Stock because any necessary qualifications
         or registrations of the Common Stock under applicable state securities
         laws cannot be obtained, the Company may purchase the 2020 Debentures
         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
         1502 or pursuant to Section 1504 in the event of a failure to satisfy,
         prior to the close of business on the Repurchase Date, any condition to
         the payment of the Repurchase Price, in whole or in part, in Common
         Stock.

                  At least three Business Days before the Company Notice Date,
         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 1505,

                  (iii) if the Company elects to pay the Repurchase Price, or a
         specified percentage thereof, in Common Stock, that the conditions to
         such manner of payment set forth in Section 1504 have been or will be
         complied with, and

                  (iv) whether the Company desires the Trustee to give the
         Company Notice required by Section 1505.

         SECTION 1503 Purchase with Cash.

                  On each Repurchase Date, at the option of the Company, the
         Repurchase Price of 2020 Debentures in respect of which a Repurchase
         Notice pursuant to Section 1501 has been given, or a specified
         percentage thereof, may be paid by

                                       43
<PAGE>   47

         the Company with cash equal to the aggregate Repurchase Price of such
         2020 Debentures. If the Company elects to purchase 2020 Debentures with
         cash, the Company Notice, as provided in Section 1505, shall be sent to
         Holders (and to beneficial owners as required by applicable law) not
         less than 20 Business Days prior to such Purchase Date (the "Company
         Notice Date").

         SECTION 1504 Payment by Issuance of Common Stock.

                  On each Repurchase Date, at the option of the Company, the
         Repurchase Price of 2020 Debentures in respect of which a Repurchase
         Notice pursuant to Section 1501 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 Repurchase Price of such 2020
         Debentures 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 Repurchase 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 of Common Stock shall be
         determined by multiplying the Market Price by such fraction and
         rounding the product to the nearest whole cent with one half cent being
         rounded upwards. It is understood that if a Holder elects to have more
         than one 2020 Debenture repurchased, the number of shares of Common
         Stock shall be based on the aggregate amount of 2020 Debentures to be
         repurchased.

                  If the Company elects to purchase the 2020 Debentures by the
         issuance of Common Stock, the Company Notice, as provided in Section
         1505, shall be sent to the Holders (and to beneficial owners as
         required by applicable law) not later than the Company Notice Date.

                  The Company's right to exercise its election to purchase the
         2020 Debentures pursuant to this Article Fifteen through the issuance
         of Common Stock shall be conditioned upon:

                  (i) the Company's not having given its Company Notice of an
         election to pay entirely in cash and its giving of timely Company
         Notice of election to purchase all or a specified percentage of the
         2020 Debentures with Common Stock as provided herein;

                                       44
<PAGE>   48

                  (ii) the registration of the Common Stock to be issued in
         respect of the payment of the Repurchase Price under the Securities Act
         or the Exchange Act, in each case, if required for the initial issuance
         thereof;

                  (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 Common Stock to be issued by the Company in payment of the
         Repurchase Price in respect of 2020 Debentures have been duly
         authorized and, when issued and delivered pursuant to the terms of this
         Indenture in payment of the Repurchase Price in respect of the 2020
         Debentures, will be validly issued, fully paid and non-assessable and,
         to the best of such counsel's knowledge, free from preemptive rights,
         and, in the case of such Officer's Certificate, stating that conditions
         (i), (ii) and (iii) above and the condition set forth in the second
         succeeding sentence 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
         2020 Debentures and the Sale Price of a share of Common Stock on each
         trading day during the period commencing on the first trading day of
         the period during which the Market Price is calculated and ending three
         Business Days prior to the applicable Repurchase Date. The Company may
         pay the Repurchase Price (or any portion thereof) in Common Stock only
         if the information necessary to calculate the Market Price is published
         in The Wall Street Journal or another daily newspaper of national
         circulation. If the foregoing conditions are not satisfied with respect
         to a Holder or Holders prior to the close of business on the Repurchase
         Date and the Company has elected to repurchase the 2020 Debentures
         pursuant to this Article Fifteen through the issuance of Common Stock,
         the Company shall pay, without further notice, the entire Repurchase
         Price of the 2020 Debentures of such Holder or Holders in cash.

                  The "Market Price" means the average of the Sale Prices of the
         Common Stock for the five trading day period ending on (if the third
         Business Day prior to the applicable Repurchase Date is a trading day,
         or if not, then on the last trading day prior to), the third Business
         Day prior to the applicable Repurchase Date 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

                                       45
<PAGE>   49

         and ending on such Repurchase Date, of any event described in Section
         1406; subject, however, to the conditions set forth in Sections 1406(f)
         and 1407.

                  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 in the composite transactions for the principal United
         States securities exchange on which the Common Stock is traded or, if
         the Common Stock is not listed on a United States national or regional
         securities exchange, as reported by the National Association of
         Securities Dealers Automated Quotation System or its successors.

         SECTION 1505 Notice of Election.

                  The Company's notice of election to repurchase with cash or
         Common Stock or any combination thereof shall be sent to the Holders in
         the manner provided in Section 106 of the Indenture at the time
         specified in Section 1503 or 1504, as applicable (the "Company
         Notice"). Such Company Notice shall state the manner of payment elected
         and shall contain the following information:

                  In the event the Company has elected to pay the Repurchase
         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 equal to such specified percentage of the Repurchase Price
         of the 2020 Debentures held by such Holder (except any cash amount to
         be paid in lieu of fractional shares);

                  (2) set forth the method of calculating the Market Price of
         the Common Stock; and

                  (3) state that because the Market Price of Common Stock will
         be determined prior to the Repurchase Date, 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
         Repurchase Date.

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

                  (A)      the Repurchase Price and the Conversion Rate;

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

                                       46
<PAGE>   50

                  (C) that 2020 Debentures as to which a Repurchase Notice has
         been given may be converted pursuant to Article Fourteen hereof only if
         the applicable Repurchase Notice has been withdrawn in accordance with
         the terms of this Indenture;

                  (D) that 2020 Debentures must be surrendered to the Paying
         Agent to collect payment;

                  (E) that the Repurchase Price for any 2020 Debenture as to
         which a Repurchase Notice has been given and not withdrawn will be paid
         promptly following the later of the Repurchase Date and the time of
         surrender of such 2020 Debenture as described in (D);

                  (F) the procedures the Holder must follow to exercise
         repurchase rights under this Article Fifteen and a brief description of
         those rights;

                  (G) briefly, the conversion rights of the 2020 Debentures; and

                  (H) the procedures for withdrawing a Repurchase Notice
         (including, without limitation, for a conditional withdrawal pursuant
         to the terms of Section 1501 or 1509).

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

                  Upon determination of the actual number of shares of Common
         Stock to be issued for each $1,000 Principal Amount of 2020 Debentures,
         the Company will publish such determination at the Company's Web site
         on the World Wide Web or through such other public medium as the
         Company may use at that time.

         SECTION 1506 Covenants of the Company.

                  All Common Stock delivered upon purchase of the 2020
         Debentures shall be newly issued shares or treasury shares, shall be
         duly authorized, validly issued, fully paid and nonassessable and shall
         be free from preemptive rights and free of any lien or adverse claim.
         The Company shall use its reasonable efforts to list or cause to have
         quoted any Common Stock to be issued to purchase 2020 Debentures on the
         principal national securities exchange or over-the-counter or other
         domestic market on which the Common Stock is then listed or quoted.

                                       47
<PAGE>   51

         SECTION 1507 Procedure upon Repurchase.

                  The Company shall deposit cash (in respect of a cash purchase
         under Section 1503 or for fractional Common Stock, as applicable) or
         Common Stock, or a combination thereof, as applicable, at the time and
         in the manner as provided in Section 1510, sufficient to pay the
         aggregate Repurchase Price of all 2020 Debentures to be purchased on
         the applicable Repurchase Date pursuant to this Article Fifteen.

                  As soon as practicable after the Repurchase 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 issuable in payment of the Repurchase Price and cash in lieu of
         any fractional shares of Common Stock. The Person in whose name the
         certificate for Common Stock is registered shall be treated as a holder
         of record of Common Stock on the Business Day following the Repurchase
         Date. Subject to Section 1504, no payment or adjustment will be made
         for dividends on the Common Stock the record date for which occurred on
         or prior to the Repurchase Date.

         SECTION 1508 Taxes.

                  If a Holder of a 2020 Debenture is paid in Common Stock, the
         Company shall pay any documentary, stamp or similar issue or transfer
         tax due on such issue of Common Stock. However, the Holder shall pay
         any such tax which is due because the Holder requests the 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 shares of
         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.

         SECTION 1509 Effect of Repurchase Notice.

                  Upon receipt by the Paying Agent of the Repurchase Notice, the
         Holder of the 2020 Debenture in respect of which such Repurchase Notice
         was given shall (unless such Repurchase Notice is withdrawn as
         specified in the following two paragraphs) thereafter be entitled to
         receive solely the Repurchase Price with respect to such 2020
         Debenture. Such Repurchase Price shall be paid to such Holder, subject
         to receipt of funds and/or Common Stock by the Paying Agent, promptly
         following the later of (x) the Repurchase Date with respect to such
         2020 Debenture (provided the conditions in Section 1501 have been
         satisfied) and (y) the time of delivery of such 2020 Debenture to the
         Paying Agent by the Holder thereof in the manner required by Section
         1501. 2020 Debentures in respect of

                                       48
<PAGE>   52

         which a Repurchase Notice has been given by the Holder thereof may not
         be converted pursuant to Article Fourteen hereof on or after the date
         of the delivery of such Repurchase Notice unless such Repurchase Notice
         has first been validly withdrawn as specified in the following two
         paragraphs.

                  A Repurchase Notice may be withdrawn by means of a written
         notice of withdrawal delivered to the office of the Paying Agent in
         accordance with the Repurchase Notice at any time prior to the close of
         business on the applicable Repurchase Date specifying:

                  (1) the certificate number of the 2020 Debenture in respect of
         which such notice of withdrawal is being submitted;

                  (2) the Principal Amount of the 2020 Debenture with respect to
         which such notice of withdrawal is being submitted; and

                  (3) the Principal Amount, if any, of such 2020 Debenture which
         remains subject to the original Repurchase Notice and which has been or
         will be delivered for purchase by the Company.

                  A written notice of withdrawal of a Repurchase Notice may be
         in the form set forth in the preceding paragraph or may be in the form
         of (i) a conditional withdrawal contained in a Repurchase Notice
         pursuant to the terms of Section 1501(1)(D) or (ii) a conditional
         withdrawal containing the information set forth in Section 1501(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 2020 Debentures pursuant to
         this Article Fifteen (other than through the issuance of Common Stock
         in payment of the Repurchase Price, including cash in lieu of
         fractional shares) if there has occurred (prior to, on or after, as the
         case may be, the giving, by the Holders of such 2020 Debentures, of the
         required Repurchase Notice) and is continuing an Event of Default
         (other than a default in the payment of the Repurchase Price with
         respect to such 2020 Debentures). The Paying Agent will promptly return
         to the respective Holders thereof any 2020 Debentures (x) with respect
         to which a Repurchase Notice has been withdrawn in compliance with this
         Indenture, or (y) held by it during the continuance of an Event of
         Default (other than a default in the payment of the Repurchase Price
         with respect to such 2020 Debentures) in which case, upon such return,
         the Repurchase Notice with respect thereto shall be deemed to have been
         withdrawn.

                                       49
<PAGE>   53

         SECTION 1510 Deposit of Repurchase Price.

                  Prior to 11:00 a.m. (New York City time) on the Business Day
         following the Repurchase Date, the Company shall deposit with the
         Trustee or with the Paying Agent an amount of money (in immediately
         available funds if deposited on such Business Day) and/or Common Stock,
         if permitted hereunder, sufficient to pay the aggregate Repurchase
         Price of all of the 2020 Debentures or portions thereof which are to be
         purchased as of the Repurchase Date.

         SECTION 1511 Securities Repurchased in Part.

                  Any 2020 Debenture which is to be purchased 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 or 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 2020 Debenture,
         without service charge, a new 2020 Debenture or 2020 Debentures, 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 2020 Debenture so surrendered which is not
         purchased.

         SECTION 1512 Comply with Securities Laws Upon Purchase of Securities.

                  In connection with any offer to purchase or purchase of
         2020 Debentures under this Article Fifteen (provided that such offer or
         purchase constitutes an "issuer tender offer" for purposes of
         Rule 13e-4 (which term, as used herein, includes any successor
         provision thereto) under the Exchange Act at the time of such offer or
         purchase), the Company shall (i) comply with Rule 13e-4 under the
         Exchange Act, (ii) file the related Schedule TO (or any successor
         schedule, form or report) under the Exchange Act, and (iii) otherwise
         comply with all Federal and state securities laws so as to permit the
         rights and obligations under Article Fifteen to be exercised in the
         time and in the manner specified in this Article Fifteen.

         SECTION 1513 Repayment to the Company.

                  The Trustee and the Paying Agent shall return to the Company
         any cash or Common Stock that remain unclaimed for two years, subject
         to applicable unclaimed property law, together with interest or
         dividends, if any, thereon held by them for the payment of the
         Repurchase Price; provided, however, that to the extent that the
         aggregate amount of cash or Common Stock deposited by the Company
         pursuant to Section 1510 exceeds the aggregate Repurchase Price of the

                                       50
<PAGE>   54

         2020 Debentures or portions thereof which the Company is obligated to
         purchase as of the Repurchase Date, then promptly after the Business
         Day following the Repurchase Date the Trustee shall return any such
         excess to the Company together with interest or dividends, if any,
         thereon. After that, Holders entitled to money must look to the Company
         for payment as general creditors, unless an applicable abandoned
         property law designates another Person.

         SECTION 1514 Conversion Arrangement on Repurchase.

                  Any Securities required to be repurchased under this
         Article Fifteen, unless surrendered for conversion before the close of
         business on the Repurchase Date, may be deemed to be purchased from the
         Holders of such Securities for an amount in cash not less than the
         Repurchase Price, by one or more investment bankers or other purchasers
         who may agree with the Company to purchase such Securities from the
         Holders, to convert them into Common Stock of the Company and to make
         payment for such Securities to the Trustee in trust for such Holders.

                                 ARTICLE SIXTEEN

                       PURCHASE OF SECURITIES AT OPTION OF
                        THE HOLDER UPON CHANGE IN CONTROL

         SECTION 1601 Right to Require Repurchase.

                  (a) If at any time that 2020 Debentures remain Outstanding
         there shall occur a Change in Control, 2020 Debentures shall be
         purchased by the Company at the option of the Holders thereof as of the
         date that is 35 Business Days after the occurrence of the Change in
         Control (the "Change in Control Purchase Date") at a purchase price
         equal to the Issue Price plus accrued Original Issue Discount through
         the Change in Control Purchase Date (or, if the option under
         Section 1701 has been exercised, the Restated Principal Amount plus
         accrued and unpaid interest from the Option Exercise Date to the Change
         in Control Purchase Date) (the "Change in Control Purchase Price"),
         subject to satisfaction by or on behalf of any Holder of the
         requirements set forth in subsection (c) of this Section 1601.

                  A "Change in Control" shall be deemed to have occurred at such
         time as (a) any Person, or any Persons acting together in a manner
         which would constitute a "group" (a "Group") for purposes of
         Section 13(d) of the Exchange Act, or any successor provision thereto,
         together with any Affiliates thereof (in each case, excluding Permitted
         Holders) become the Beneficial Owners, directly or indirectly, of
         capital stock of the Company, entitling such Person or Persons and its
         or their Affiliates to exercise more than 50% of the total voting power
         of all classes of the Company's capital stock entitled to vote
         generally in the election

                                       51
<PAGE>   55

         of the Company's directors or (b) the Company shall consolidate with or
         merge into any other Person (other than a Subsidiary), or any other
         Person (other than a Subsidiary) shall consolidate with or merge into
         the Company, or the Company shall sell, convey, transfer or lease its
         properties and assets substantially as an entirety to any Person other
         than a Subsidiary, and, in the case of any such transaction the
         outstanding Common Stock is reclassified into, exchanged for or
         converted into the right to receive any other property or security,
         unless the stockholders of the Company immediately before such
         transaction own, directly or indirectly, immediately following such
         transaction, at least a majority of the combined voting power of the
         outstanding voting securities of the Person resulting from such
         transaction or the Person acquiring such properties and assets,
         entitled to vote generally on the election of such resulting or
         acquiring Person's directors, in substantially the same proportion as
         their ownership of the Common Stock immediately before such
         transaction, provided, however, that, with respect to both clause (a)
         and (b), a Change in Control shall not be deemed to have occurred if at
         least 50% of the consideration (excluding cash payments for fractional
         shares) in the transaction or transactions constituting the Change in
         Control consists of shares of voting common stock of such 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.

                  The term "Beneficial Owner" shall be determined in accordance
         with Rules 13d-3 and 13d-5 promulgated by the Securities and Exchange
         Commission under the Exchange Act or any successor provision thereto,
         except that a Person shall be deemed to have "beneficial ownership" of
         all shares that such Person has the right to acquire, whether such
         right is exercisable immediately or only after the passage of time.

                  "Permitted Holders" means Loews Corporation, a Delaware
         corporation, and any of its Subsidiaries.

                  (b) Within 15 Business Days after the occurrence of a Change
         in Control, the Company shall mail a written notice of the Change in
         Control to the Trustee and to each Holder. The notice shall include the
         form of a Change in Control Purchase Notice to be completed by the
         Holder and shall state:

                  (1) the date of such Change in Control and, briefly, the
         events causing such Change in Control;

                  (2) the date by which the Change in Control Purchase Notice
         pursuant to this Section 1601 must be given;

                                       52
<PAGE>   56

                  (3) the Change in Control Purchase Date;

                  (4) the Change in Control Purchase Price;

                  (5) briefly, the conversion rights of the 2020 Debentures;

                  (6) the name and address of each Paying Agent and Conversion
         Agent;

                  (7) the Conversion Rate and any adjustments thereto;

                  (8) that 2020 Debentures as to which a Change in Control
         Purchase Notice has been given may be converted into Common Stock
         pursuant to Article Fourteen only to the extent that the Change in
         Control Purchase Notice has been withdrawn in accordance with the terms
         of this Indenture;

                  (9) the procedures that the Holder must follow to exercise
         rights under this Section 1601;

                  (10) the procedures for withdrawing a Change in Control
         Purchase Notice, including a form of notice of withdrawal; and

                  (11) that the Holder must satisfy the requirements set forth
         in the 2020 Debentures in order to convert the Securities.

                  If any of the 2020 Debentures is in the form of a Global
         Security, then the Company shall modify such notice to the extent
         necessary to accord with the procedures of the Depositary applicable to
         the repurchase of Global Securities

                  (c) A Holder may exercise its rights specified in
         subsection (a) of this Section 1601 upon delivery of a written notice
         (which shall be in substantially the form included as an attachment to
         the 2020 Debentures and which may be delivered by letter, overnight
         courier, hand delivery, facsimile transmission or in any other written
         form and, in the case of Global Securities, may be delivered
         electronically or by other means in accordance with the Depositary's
         customary procedures) of the exercise of such rights (a "Change in
         Control Purchase Notice") to any Paying Agent at any time prior to the
         close of business on the Business Day next preceding the Change in
         Control Purchase Date.

                   The delivery of such 2020 Debenture to any Paying Agent
           (together with all necessary endorsements) at the office of such
           Paying Agent shall be a

                                       53
<PAGE>   57

         condition to the receipt by the Holder of the Change in Control
         Purchase Price therefor.

                  The Company shall purchase from the Holder thereof, pursuant
         to this Section 1601, a portion of a 2020 Debenture 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
         2020 Debenture pursuant to Sections 1601 through 1606 also apply to the
         purchase of such portion of such 2020 Debenture.

                  Notwithstanding anything herein to the contrary, any Holder
         delivering to a Paying Agent the Change in Control Purchase Notice
         contemplated by this subsection (c) shall have the right to withdraw
         such Change in Control Purchase Notice in whole or as to a portion
         thereof that is a Principal Amount of $1,000 or an integral multiple
         thereof at any time prior to the close of business on the Business Day
         next preceding the Change in Control Purchase Date by delivery of a
         written notice of withdrawal to the Paying Agent in accordance with
         Section 1602.

                  A Paying Agent shall promptly notify the Company of the
         receipt by it of any Change in Control Purchase Notice or written
         withdrawal thereof.

                  Anything herein to the contrary notwithstanding, in the case
         of Global Securities, any Change in Control Purchase Notice may be
         delivered or withdrawn and such 2020 Debentures may be surrendered or
         delivered for purchase in accordance with the applicable procedures of
         the Depositary as in effect from time to time.

         SECTION 1602 Effect of Change in Control Purchase Notice.

                  Upon receipt by any Paying Agent of the Change in Control
         Purchase Notice specified in Section l601(c), the Holder of the
         2020 Debenture in respect of which such Change in Control Purchase
         Notice was given shall (unless such Change in Control Purchase Notice
         is withdrawn as specified below) thereafter be entitled to receive the
         Change in Control Purchase Price with respect to such 2020 Debenture.
         Such Change in Control Purchase Price shall be paid to such Holder
         promptly following the later of (a) the Change in Control Purchase Date
         with respect to such 2020 Debenture (provided the conditions in
         Section 1601(c) have been satisfied) and (b) the time of delivery of
         such 2020 Debenture to a Paying Agent by the Holder thereof in the
         manner required by Section 1601(c). 2020 Debentures in respect of which
         a Change in Control Purchase Notice has been given by the Holder
         thereof may not be converted into Common Stock on or after the date of
         the delivery of such Change in Control Purchase Notice unless such
         Change in Control Purchase Notice has first been validly withdrawn.

                                       54
<PAGE>   58

                  A Change in Control Purchase Notice may be withdrawn by means
         of a written notice (which may be delivered by letter, overnight
         courier, hand delivery, facsimile transmission or in any other written
         form and, in the case of Global Securities, may be delivered
         electronically or by other means in accordance with the Depositary's
         customary procedures) of withdrawal delivered by the Holder to a Paying
         Agent at any time prior to the close of business on the Business Day
         immediately preceding the Change in Control Purchase Date, specifying
         the Principal Amount of the Security or portion thereof (which must be
         a Principal Amount of $1,000 or an integral multiple of $1,000 in
         excess thereof) with respect to which such notice of withdrawal is
         being submitted.

         SECTION 1603 Deposit of Change in Control Purchase Price.

                  On or before 11:00 a.m. New York City time on the Change in
         Control Purchase Date, the Company shall deposit with the Trustee or
         with a Paying Agent (other than the Company or an Affiliate of the
         Company) an amount of money (in immediately available funds if
         deposited on such Business Day) sufficient to pay the aggregate Change
         in Control Purchase Price of all the 2020 Debentures or portions
         thereof that are to be purchased as of such Change in Control Purchase
         Date. The manner in which the deposit required by this Section 1603 is
         made by the Company shall be at the option of the Company, provided,
         however, that such deposit shall be made in a manner such that the
         Trustee or a Paying Agent shall have immediately available funds on the
         Change in Control Purchase Date.

                  If a Paying Agent holds, in accordance with the terms hereof,
         money sufficient to pay the Change in Control Purchase Price of any
         2020 Debenture for which a Change in Control Purchase Notice has been
         tendered and not withdrawn in accordance with this Indenture then, on
         the Change in Control Purchase Date, such 2020 Debenture will cease to
         be Outstanding and the rights of the Holder in respect thereof shall
         terminate (other than the right to receive the Change in Control
         Purchase Price as aforesaid). The Company shall publicly announce the
         Principal Amount of 2020 Debentures purchased as a result of such
         Change in Control on or as soon as practicable after the Change in
         Control Purchase Date.

         SECTION 1604 Securities Purchased In Part.

                  Any 2020 Debenture that is to be purchased only in part shall
         be surrendered at the office of a Paying Agent and promptly after the
         Change in Control Purchase Date the Company shall execute and the
         Trustee shall authenticate and deliver to the Holder of such 2020
         Debenture, without service charge, a new 2020 Debenture or 2020
         Debentures, of such authorized denomination or denominations as may be
         requested by such Holder, in aggregate

                                       55
<PAGE>   59

         Principal Amount equal to, and in exchange for, the portion of the
         Principal Amount of the 2020 Debenture so surrendered that is not
         purchased.

         SECTION 1605 Compliance With Securities Laws Upon Purchase of
         Securities.

                  In connection with any offer to purchase or purchase of 2020
         Debentures under Section 1601, the Company shall (a) comply with Rule
         13e-4 (or any successor to either such Rule), if applicable, under the
         Exchange Act, (b) file the related Schedule TO (or any successor or
         similar schedule, form or report) if required under the Exchange Act,
         and (c) otherwise comply with all federal and state securities laws in
         connection with such offer, all so as to permit the rights of the
         Holders and obligations of the Company under Sections 1601 through 1606
         to be exercised in the time and in the manner specified therein.

         SECTION 1606 Repayment to the Company.

                  To the extent that the aggregate amount of cash deposited by
         the Company pursuant to Section 1603 exceeds the aggregate Change in
         Control Purchase Price together with interest, if any, thereon of the
         2020 Debentures or portions thereof that the Company is obligated to
         purchase, then promptly after the Change in Control Purchase Date the
         Trustee or a Paying Agent, as the case may be, shall return any such
         excess to the Company.

                                ARTICLE SEVENTEEN

                          SPECIAL TAX EVENT CONVERSION

         SECTION 1701 Optional Conversion to Interest-Bearing Securities Upon
         Tax Event.

                  From and after (i) the date (the "Tax Event Date") of the
         occurrence of a Tax Event and (ii) the date the Company exercises such
         option, whichever is later (the "Option Exercise Date"), at the option
         of the Company with respect to its 2020 Debentures only, interest in
         lieu of future Original Issue Discount shall accrue at the rate of 3.5%
         per annum on a restated principal amount per $1,000 original Principal
         Amount (the "Restated Principal Amount") equal to the Issue Price plus
         Original Issue Discount accrued to the Option Exercise Date and shall
         be payable semiannually on each Interest Payment Date to holders of
         record at the close of business on each Regular Record Date immediately
         preceding 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 on which interest has been paid or, if
         no interest has been paid, from the Option Exercise Date. Within 15
         days of the occurrence of a Tax Event, the Company

                                       56
<PAGE>   60

         shall mail a written notice of such Tax Event by first-class mail to
         the Trustee and within 15 days of its exercise of such option the
         Company shall mail a written notice of the Option Exercise Date by
         first-class mail to the Trustee and Holders of the 2020 Debentures.
         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
         2020 Debenture. 2020 Debentures 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
         2020 Debentures to interest-bearing 2020 Debentures.

                                  ARTICLE THREE

                            MISCELLANEOUS PROVISIONS

SECTION 301 Integral Part.

         This Second Supplemental Indenture constitutes an integral part of the
Indenture with respect to the 2020 Debentures only.

SECTION 302 General Definitions.

         For all purposes of this Second 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 Second Supplemental Indenture.

SECTION 303 Adoption, Ratification and Confirmation.

         The Indenture, as supplemented and amended by this Second Supplemental
Indenture, is in all respects hereby adopted, ratified and confirmed, and this
Second Supplemental Indenture shall be deemed part of the Indenture in the
manner and to the extent herein and therein provided. The provisions of this
Supplemental Indenture shall, subject to the terms hereof, supersede
the provisions of the Indenture to the extent the Indenture is inconsistent
herewith.

                                       57

<PAGE>   61
SECTION 304 Counterparts.

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

SECTION 305 Governing Law.

         THIS SECOND SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY AND CONSTRUED
IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO THE
CONFLICTS OF LAW RULES OF SAID STATE.

SECTION 306 Conflict of Any Provision of Indenture with Trust Indenture Act of
            1939.

         If and to the extent that any provision of this Second Supplemental
Indenture limits, qualifies or conflicts with a provision required under the
terms of the Trust Indenture Act of 1939, as amended, such Trust Indenture Act
provision shall control.

SECTION 307 Effect of Headings.

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

SECTION 308 Severability of Provisions.

         In case any provision in this Second Supplemental Indenture or in the
2020 Debentures shall be invalid, illegal or unenforceable, the validity,
legality and enforceability of the remaining provisions shall not in any way be
affected or impaired thereby.

SECTION 309 Successors and Assigns.

         All covenants and agreements in this Second Supplemental Indenture by
the parties hereto shall bind their respective successors and assigns and inure
to the benefit of their respective successors and assigns, whether so expressed
or not.

SECTION 310 Benefit of Second Supplemental Indenture.

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

                                       58

<PAGE>   62

SECTION 311 Acceptance by Trustee.

         The Trustee accepts the amendments to the Indenture effected by this
Second Supplemental Indenture and agrees to execute the trusts created by the
Indenture as hereby amended, but only upon the terms and conditions set forth
in this Second Supplemental Indenture and the Indenture. Without limiting the
generality of the foregoing, the Trustee assumes no responsibility for the
correctness of the recitals contained herein, which shall be taken as the
statements of the Company and except as provided in the Indenture the Trustee
shall not be responsible or accountable in any way whatsoever for or with
respect to the validity or execution or sufficiency of this Second Supplemental
Indenture and the Trustee makes no representation with respect thereto.

                                       59

<PAGE>   63

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

                                  DIAMOND OFFSHORE DRILLING, INC.

                                  By: /s/ LAWRENCE R. DICKERSON
                                      ------------------------------------------
                                      Name: LAWRENCE R. DICKERSON
                                            ------------------------------------
                                      Title: PRESIDENT & CHIEF OPERATING OFFICER
                                             -----------------------------------

                                  THE CHASE MANHATTAN BANK

                                  By: /s/ RONALD J. HALLERAN
                                      ------------------------------------------
                                     Name: RONALD J. HALLERAN
                                           -------------------------------------
                                     Title: ASSISTANT VICE PRESIDENT
                                            ------------------------------------

<PAGE>   64

STATE OF TEXAS )

COUNTY OF HARRIS )

         On the 6th day of June, 2000, before me personally came LAWRENCE R.
DICKERSON to me known, who, being by me duly sworn, did depose and say that he
is PRESIDENT of DIAMOND OFFSHORE DRILLING, INC., one of the corporations
described in and which executed the foregoing instrument; that he knows the seal
of said corporation; that the seal affixed to said instrument is such corporate
seal; that it was so affixed by authority of the Board Directors of said
corporation, and that he signed his name thereto by like authority.

[NOTARY STAMP]
                                             /s/ PAULA L. HEADINGTON
                                             -----------------------------------
                                                           Notary

STATE OF NEW YORK )

COUNTY OF NEW YORK )

         On the 6th day of June, 2000, before me personally came R.J. HALLERAN,
to me known, who, being by me duly sworn, did depose and say that such person is
a ASSISTANT VICE PRESIDENT of THE CHASE MANHATTAN BANK, one of the corporations
described in and which executed the foregoing instrument; that he knows the seal
of said corporation; that the seal affixed to said instrument is such corporate
seal; that it was so affixed by authority of the Board Directors of said
corporation, and that such person signed his name thereto by like authority.

                                             /s/ EMILY FAYAN
                                             -----------------------------------
                                                           Notary

                                                       [NOTARY STAMP]
<PAGE>   65

                                                                         ANNEX A

                                 GLOBAL SECURITY

                           [FORM OF FACE OF SECURITY]

         [UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE
OF THE DEPOSITORY TRUST COMPANY TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF
TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE
NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (AND ANY PAYMENT HEREON IS MADE
TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY), ANY TRANSFER, PLEDGE OR OTHER
USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE
REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

         THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE
HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITARY OR A
NOMINEE THEREOF. THIS SECURITY IS EXCHANGEABLE FOR SECURITIES REGISTERED IN THE
NAME OF A PERSON OTHER THAN THE DEPOSITARY OR ITS NOMINEE ONLY IN THE LIMITED
CIRCUMSTANCES DESCRIBED IN THE INDENTURE AND, UNLESS AND UNTIL IT IS EXCHANGED
IN WHOLE OR IN PART FOR SECURITIES IN DEFINITIVE FORM, THIS SECURITY MAY NOT BE
TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY
OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE
DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR
A NOMINEE OF SUCH SUCCESSOR DEPOSITARY.](1)

         [THIS SECURITY (OR ITS PREDECESSOR) WAS ORIGINALLY ISSUED IN A
TRANSACTION EXEMPT FROM REGISTRATION UNDER THE UNITED STATES SECURITIES ACT OF
1933 (THE "SECURITIES ACT"), AND THIS SECURITY AND THE COMMON STOCK ISSUABLE
UPON CONVERSION THEREOF MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED IN THE
ABSENCE OF SUCH REGISTRATION OR AN APPLICABLE EXEMPTION THEREFROM. EACH
PURCHASER OF THIS SECURITY IS HEREBY NOTIFIED THAT THE SELLER OF THIS SECURITY
MAY BE RELYING ON THE EXEMPTION FROM THE PROVISIONS OF SECTION 5 OF THE
SECURITIES ACT PROVIDED BY RULE 144A THEREUNDER.

----------
(1)     These paragraphs should be included only if the Security is a Global
Security.

                                      A-1

<PAGE>   66

         THE HOLDER OF THIS SECURITY AGREES FOR THE BENEFIT OF THE COMPANY THAT
(A) THIS SECURITY AND THE COMMON STOCK ISSUABLE UPON CONVERSION THEREOF MAY BE
OFFERED, RESOLD, PLEDGED OR OTHERWISE TRANSFERRED, ONLY (I) IN THE UNITED STATES
TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QUALIFLED INSTITUTIONAL
BUYER (AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT) IN A TRANSACTION
MEETING THE REQUIREMENTS OF RULE 144A, (II) OUTSIDE THE UNITED STATES IN AN
OFFSHORE TRANSACTION IN ACCORDANCE WITH RULE 904 UNDER THE SECURITIES ACT, (III)
PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT PROVIDED BY
RULE 144 THEREUNDER (IF AVAILABLE) OR (IV) PURSUANT TO AN EFFECTIVE REGISTRATION
STATEMENT UNDER THE SECURITIES ACT, IN EACH OF CASES (I) THROUGH (IV) IN
ACCORDANCE WITH ANY APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED
STATES, AND (B) THE HOLDER WILL, AND EACH SUBSEQUENT HOLDER IS REQUIRED TO,
NOTIFY ANY PURCHASER OF THIS SECURITY FROM IT OF THE RESALE RESTRICTIONS
REFERRED TO IN (A) ABOVE.](2)

----------
(2) [These paragraphs to be included only if the Security is a Transfer
Restricted Security.]

                                      A-2
<PAGE>   67

                           [FORM OF FACE OF SECURITY]

                         DIAMOND OFFSHORE DRILLING, INC.

               ZERO COUPON CONVERTIBLE DEBENTURES DUE JUNE 6, 2020

Issue Date: June 6, 2000                                  Maturity: June 6, 2020

Principal Amount: $_________                                   CUSIP:25271C AB 8

Original Issue Discount: $500.40                            Issue Price: $499.60
(per $1,000 Principal Amount)                      (per $1,000 Principal Amount)

Registered: No. R-

         Diamond Offshore Drilling, Inc., a Delaware corporation (herein called
the "Company", which term includes any successor corporation under the indenture
hereinafter referred to), for value received, hereby promises to pay to Cede &
Co., or registered assigns, the principal sum of ___________________ DOLLARS
($____________) on June 6, 2020 [(or such greater or lesser amount as is
indicated on the Schedule of Exchanges of Securities on the other side of this
Security)](3). The principal of this Security shall not bear interest, except in
the case of default in payment of principal upon acceleration, redemption or
maturity or as specified on the other side of this Security. Original Issue
Discount will accrue as specified on the other side of this Security. This
Security is convertible as specified on the other side of this Security.

         Payment of the principal of and interest, if any, on this Security will
be made at the office or agency of the Company maintained for that purpose in
The City of New York, in such coin or currency of the United States of America
as at the time of payment is legal tender for payment of public and private
debts; provided, however, that at the option of the Company, payment of
interest, if any, may be made by check mailed to the address of the Person
entitled thereto as such address shall appear in the Security Register.

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

         Unless the certificate of authentication hereon has been executed by
the Trustee referred to on the reverse hereof by manual signature, this Security
shall not be entitled to any benefit under the Indenture or be valid or
obligatory for any purpose.

----------
(3) [These paragraphs to be included only if the Security is a Transfer
Restricted Security.]

                                      A-3

<PAGE>   68

         IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed under its corporate seal.

Dated:

                                      DIAMOND OFFSHORE DRILLING, INC.

                                      By:
                                         ---------------------------------------
                                         Name:
                                         Title:

---------------------------------
Corporate Secretary

                                       A-4

<PAGE>   69

                     TRUSTEE'S CERTIFICATE OF AUTHENTICATION

         This is one of the Securities of the series designated therein
referred to in the within-mentioned Indenture.

                                        THE CHASE MANHATTAN BANK, as Trustee

                                        ----------------------------------------
                                        Authorized Signature

Date of Authentication: ______________

                                      A-5
<PAGE>   70

                       [FORM OF REVERSE SIDE OF SECURITY]

                         DIAMOND OFFSHORE DRILLING, INC.

               ZERO COUPON CONVERTIBLE DEBENTURE DUE JUNE 6, 2020

         This Security is one of a duly authorized issue of senior securities of
the Company (herein called the "Securities"), issued and to be issued in one or
more series under an Indenture, dated as of February 4, 1997, as amended by the
Second Supplemental Indenture thereto, dated as of June 6, 2000 (as so amended,
herein called the "Indenture"), between the Company and The Chase Manhattan
Bank, as Trustee (herein called the "Trustee", which term includes any successor
trustee under the Indenture), to which Indenture and all indentures supplemental
thereto reference is hereby made for a statement of the respective rights,
limitations of rights, duties and immunities thereunder of the Company, the
Trustee and the Holders of the Securities and of the terms upon which the
Securities are, and are to be, authenticated and delivered. This Security is one
of the series designated on the face hereof, limited in aggregate principal
amount at maturity to $805,000,000.

INTEREST

         This Security shall not bear interest, except as specified in this
paragraph or as described under "Tax Event". If the Principal Amount hereof or
any portion of such Principal Amount is not paid when due (whether upon
acceleration pursuant to Section 502 of the Indenture, upon the date set for
payment of the Redemption Price as described under "Optional Redemption", upon
the date set for payment of the Change in Control Purchase Price pursuant to
"Purchase of Securities at Option of Holder Upon a Change in Control", upon the
date set for payment of the Repurchase Price under "Repurchase by the Company at
the Option of the Holder" or upon the Stated Maturity of this Security) or if
interest due hereon, if any (or any portion of such interest), is not paid when
due, then in each such case the overdue amount shall, to the extent permitted by
law, bear interest at the rate of 3.5% per annum, compounded semi-annually,
which interest shall accrue from the date such overdue amount was originally due
to the date payment of such amount, including interest thereon, has been made or
duly provided for. All such interest shall be payable as set forth in the
Indenture. The accrual of such interest on overdue amounts shall be in lieu of,
and not in addition to, the continued accrual of Original Issue Discount.
Original Issue Discount (the difference between the Issue Price and the
Principal Amount of the Security), in the period during which a Security remains
outstanding, shall accrue at 3.5% per annum, on a semiannual bond equivalent
basis using a 360-day year composed of twelve 30-day months, from the Issue Date
of this Security.

METHOD OF PAYMENT

         Payments in respect of principal of and interest, if any, on the
Securities shall be made by the Company in immediately available funds.

                                      A-6
<PAGE>   71

OPTIONAL REDEMPTION

         No sinking fund is provided for the Securities. The Securities are
redeemable as a whole, or from time to time in part, at any time at the option
of the Company at the Redemption Price set forth below, after June 6, 2005.

         The table below shows Redemption Prices of a Security per $1,000
Principal Amount on the dates shown below and at Stated Maturity, which prices
reflect accrued Original Issue Discount calculated through each such date. The
Redemption Price of a Security redeemed between such dates shall include an
additional amount reflecting the additional Original Issue Discount accrued
since the immediately preceding date in the table.

<TABLE>
<CAPTION>
                                  (1)                (2)                    (3)
                            DEBENTURE ISSUE     ACCRUED ORIGINAL     REDEMPTION PRICE
REDEMPTION DATE                  PRICE           ISSUE DISCOUNT           (1)+(2)
---------------             ---------------     ----------------     ----------------
<S>                         <C>                 <C>                  <C>
June 6, 2005............       $ 499.60            $  94.65             $   594.25
June 6, 2006............         499.60              115.63                 615.23
June 6, 2007............         499.60              137.35                 636.95
June 6, 2008............         499.60              159.84                 659.44
June 6, 2009............         499.60              183.12                 682.72
June 6, 2010............         499.60              207.22                 706.82
June 6, 2011............         499.60              232.18                 731.78
June 6, 2012............         499.60              258.02                 757.62
June 6, 2013............         499.60              284.76                 784.36
June 6, 2014............         499.60              312.46                 812.06
June 6, 2015............         499.60              341.13                 840.73
June 6, 2016............         499.60              370.81                 870.41
June 6, 2017............         499.60              401.54                 901.14
June 6, 2018............         499.60              433.36                 932.96
June 6, 2019............         499.60              466.30                 965.90
At stated maturity......         499.60              500.40               1,000.00
</TABLE>

         If converted to an interest-bearing debenture following the occurrence
of a Tax Event, this Security will be redeemable at the Restated Principal
Amount plus accrued and unpaid interest from the date of such conversion to the
Redemption Date; but in no event will this Security be redeemable before June 6,
2005.

         If the Company redeems less than all of the outstanding Securities, the
Trustee will select the Securities to be redeemed (i) by lot; (ii) pro rata; or
(iii) by another method the Trustee considers fair and appropriate. If the
Trustee selects a portion of a Holder's Securities for partial redemption and
the Holder converts a portion of the same Securities, the converted portion will
be deemed to be from the portion selected for redemption.

                                      A-7
<PAGE>   72

NOTICE OF REDEMPTION

         Notice of redemption will be mailed by first-class mail at least 15
days but not more than 60 days before the Redemption Date to each Holder of
Securities to be redeemed at its registered address. Securities in denominations
larger than $1,000 Principal Amount may be redeemed in part, but only in whole
multiples of $1,000. On and after the Redemption Date, subject to the deposit
with the Paying Agent of funds sufficient to pay the Redemption Price, Original
Issue Discount (or interest, if the Security is converted to an interest-bearing
debenture) ceases to accrue on Securities or portions thereof called for
redemption.

PURCHASE OF SECURITIES AT OPTION OF HOLDER UPON A CHANGE IN CONTROL

         At the option of the Holder and subject to the terms and conditions of
the Indenture, the Company shall become obligated to purchase all or any part
specified by the Holder (so long as the Principal Amount of such part is $1,000
or an integral multiple of $1,000 in excess thereof) of the Securities held by
such Holder on the date that is 35 Business Days after the occurrence of a
Change in Control, at a Change in Control Purchase Price equal to the Issue
Price plus accrued Original Issue Discount through the Change in Control
Purchase Date. The Holder shall have the right to withdraw any Change in Control
Purchase Notice (in whole or in a portion thereof that is $1,000 Principal
Amount or an integral multiple of $1,000 in excess thereof) at any time prior
to the close of business on the Business Day prior to the Change in Control
Purchase Date by delivering a written notice of withdrawal to the Paying Agent
in accordance with the terms of the Indenture.

         If prior to a Change in Control Purchase Date this Security has been
converted to an interest-bearing debenture following the occurrence of a Tax
Event, the Change in Control Purchase Price shall be equal to the Restated
Principal Amount plus accrued and unpaid interest from the date of conversion to
the Change in Control Purchase Date.

CONVERSION

         A Holder of a Security may convert the Security into shares of Common
Stock at any time until the close of business on the Business Day prior to the
Stated Maturity; provided, however, that if the Security is called for
redemption, the conversion right will terminate at the close of business on the
Business Day immediately preceding the Redemption Date for such Security or such
earlier date as the Holder presents such Security for redemption (unless the
Company shall default in making the redemption payment when due, in which case
the conversion right shall terminate at the close of business on the date such
default is cured and such Security is redeemed). A Security in respect of which
a Holder has delivered a Repurchase Notice exercising the option of such Holder
to require the Company to purchase such Security may be converted only if such
notice of exercise is withdrawn in accordance with the terms of the Indenture.
The initial Conversion Rate is 8.6075 shares of Common Stock per $1,000
Principal Amount, subject to adjustment in certain events described in the
Indenture. The Company will deliver cash or a check in lieu of any fractional
share of Common Stock.

                                      A-8
<PAGE>   73
         In the event the Company exercises its option pursuant to Section 1701
of the Indenture to have interest in lieu of Original Issue Discount accrue on
the Security following a Tax Event, the Holder will be entitled on conversion to
receive the same number of shares of Common Stock such Holder would have
received if the Company had not exercised such option. If the Company exercises
such option, Securities surrendered for conversion during the period from the
close of business on any Regular Record Date immediately preceding any Interest
Payment Date to the opening of business of such Interest Payment Date (except
Securities or portions of Securities to be redeemed on a Redemption Date
occurring during the period from the close of business on a Regular Record Date
and ending on the opening of business on the first Business Day after the next
Interest Payment Date, or if this Interest Payment Date is not a Business Day,
the second Business Day after the Interest Payment Date) must be accompanied by
payment from the Holder of an amount equal to the interest thereon that the
registered Holder is to receive from the Company on such Interest Payment Date.
Except where Securities surrendered for conversion must be accompanied by
payment as described above, no interest on converted Securities will be payable
by the Company on any Interest Payment Date subsequent to the date of
conversion.

         A Holder may convert a portion of a Security if the Principal Amount of
such portion is $1,000 or an integral multiple of $1,000. No payment or
adjustment will be made for dividends on the Common Stock except as provided in
the Indenture. On conversion of a Security, that portion of accrued Original
Issue Discount (and interest if the Security is converted to an interest-bearing
debenture) attributable to the period from the Issue Date (or, in the case of
interest, if the Company has exercised the option referred to in "Tax Event",
the later of (x) the date of such exercise and (y) the date on which interest
was last paid) through the Conversion Date with respect to the converted
Security shall not be cancelled, extinguished or forfeited, but rather shall be
deemed to be paid in full to the Holder thereof through the 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 terms
hereof; and the fair market value of such shares of Common Stock (together with
any such cash payment in lieu of fractional shares) shall be treated as issued,
to the extent thereof, first in exchange for Original Issue Discount (and
interest, if the Company has exercised its option provided for in "Tax Event")
accrued through the Conversion Date, and the balance, if any, of such fair
market value of such Common Stock (and any such cash payment) shall be treated
as issued in exchange for the Issue Price of the Security being converted
pursuant to the provisions hereof.

         No fractional shares will be issued upon conversion; in lieu thereof,
an amount will be paid in cash based upon the closing price of the Common Stock
on the Trading Day immediately prior to the Conversion Date.

         To convert a Security, a Holder must (a) complete and manually sign the
conversion notice set forth below and deliver such notice to a Conversion Agent,
(b) surrender the Security to the Conversion Agent, (c) furnish appropriate
endorsements and transfer documents (including any certification that may be
required under applicable law) if required by the Conversion Agent, and (d) pay
any transfer or similar tax, if required.

                                       A-9

<PAGE>   74

REPURCHASE BY THE COMPANY AT THE OPTION OF THE HOLDER

         Subject to the terms and conditions of the Indenture, the Company shall
become obligated to purchase, at the option of the Holder, the Securities held
by such Holder on the following Repurchase Dates and at the following Repurchase
Prices per $1,000 Principal Amount, upon delivery of a Repurchase Notice
containing the information set forth in the Indenture, at any time from the
opening of business on the date that is 20 Business Days prior to such
Repurchase Date until the close of business on such Repurchase Date and upon
delivery of the Securities to the Paying Agent by the Holder as set forth in the
Indenture.

<TABLE>
<CAPTION>
               REPURCHASE               REPURCHASE
                  DATE                     PRICE
               ----------               ----------
              <S>                       <C>
              June 6, 2005...........    $ 594.25
              June 6, 2010...........    $ 706.82
              June 6, 2015...........    $ 840.73
</TABLE>

         The Repurchase Price (equal to the Issue Price plus accrued Original
Issue Discount through the Repurchase Date) may be paid, at the option of the
Company, in cash or by the issuance of Common Stock (as provided in the
Indenture), or in any combination thereof.

         If prior to a Repurchase Date this Security has been converted to an
interest-bearing debenture following the occurrence of a Tax Event, the
Repurchase Price will be equal to the Restated Principal Amount plus accrued and
unpaid interest from the date of conversion to the Repurchase Date.

         Holders have the right to withdraw any Repurchase Notice by delivering
to the Paying Agent a written notice of withdrawal prior to the close of
business on the Repurchase Date in accordance with the provisions of the
Indenture.

         If cash (and/or securities if permitted under the Indenture) sufficient
to pay the Repurchase Price of all Securities or portions thereof to be
purchased as of the Repurchase Date, is deposited with the Paying Agent on the
Business Day following the Repurchase Date, Original Issue Discount (or
interest, if this Security has been converted to an interest-bearing debenture
following the occurrence of a Tax Event) ceases to accrue on such Securities (or
portions thereof) immediately after such Repurchase Date, and the Holder thereof
shall have no other rights as such (other than the right to receive the
Repurchase Price upon surrender of such Security).

TAX EVENT

         From and after (i) the date (the "Tax Event Date") of the occurrence of
a Tax Event and (ii) the date the Company exercises such option, whichever is
later (the "Option Exercise Date"), at the option of the Company, interest in
lieu of future Original Issue Discount shall accrue at the rate of 3.5% per
annum on a Principal Amount per Security (the "Restated Principal Amount") equal
to the

                                      A-10

<PAGE>   75
Issue Price plus Original Issue Discount accrued through the Option Exercise
Date and shall be payable semiannually on June 6 and December 6 of each year
(each an "Interest Payment Date") to holders of record at the close of business
on May 23 or November 22 (each a "Regular Record Date") immediately preceding
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, 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.

         Except as otherwise specified with respect to the Securities, any
Defaulted Interest on any Security shall forthwith cease to be payable to the
registered Holder thereof on the relevant Regular Record Date by virtue of
having been such Holder, and such Defaulted Interest may be paid by the Company
as provided for in Section 307 of the Indenture.

CONVERSION ARRANGEMENT ON CALL FOR REDEMPTION

         Any Securities called for redemption, unless surrendered for conversion
before the close of business on the Redemption Date, may be deemed to be
purchased from the Holders of such Securities at an amount not less than the
Redemption Price, by one or more investment bankers or other purchasers who may
agree with the Company to purchase such Securities from the Holders, to convert
them into Common Stock of the Company and to make payment for such Securities to
the Paying Agent in trust for such Holders.

TRANSFER

         As provided in the Indenture and subject to certain limitations therein
set forth, the transfer of this Security is registrable in the Security
Register, upon surrender of this Security for registration or transfer at the
office or agency in a Place of Payment for Securities of this series, duly
endorsed by, or accompanied by a written instrument of transfer in form
satisfactory to the Company and the Security Registrar duly executed by, the
Holder hereof or his attorney duly authorized in writing, and thereupon one or
more new Securities of this series, of any authorized denominations and for the
same aggregate principal amount, executed by the Company and authenticated and
delivered by the Trustee, will be issued to the designated transferee or
transferees.

         The Securities of this series are issuable only in registered form
without coupons in denominations of $1,000 and any integral multiple thereof. As
provided in the Indenture and subject to certain limitations set forth therein
and on the face of this Security, Securities of this series are exchangeable for
a like aggregate principal amount of Securities of this series of a different
authorized denomination as requested by the Holder surrendering the same.

                                      A-11
<PAGE>   76

         No service charge shall be made for any such registration of transfer
or exchange, but the Company may require payment of a sum sufficient to cover
any tax or other governmental charge payable in connection therewith.

         Prior to due presentment of this Security for registration of transfer,
the Company, the Trustee or any agent of the Company or the Trustee may treat
the Person in whose name this Security is registered as the owner hereof for all
purposes, whether or not this Security be overdue, and neither the Company, the
Trustee nor any such agent shall be affected by notice to the contrary.

AMENDMENT, SUPPLEMENT AND WAIVER

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

SUCCESSOR CORPORATION

         When a successor corporation assumes all the obligations of its
predecessor under the Securities and the Indenture in accordance with the terms
and conditions of the Indenture, the predecessor corporation will (except in
certain circumstances specified in the Indenture) be released from those
obligations.

DEFAULTS AND REMEDIES

         Under the Indenture, Events of Default include (i) default in the
payment of interest which default continues for a period of 30 days, after the
Securities have been converted to semiannual coupon debentures following a Tax
Event, or in the payment of any Additional Interest; (ii) default in payment of
the Principal Amount (or, if the Securities have been converted to semiannual
coupon debentures following a Tax Event, the Restated Principal Amount), Issue
Price plus accrued Original Issue Discount, Redemption Price, Repurchase Price
or Change in Control Purchase Price, as the case may be, in respect of the
Securities when the same becomes due and payable; (iii) failure by the Company
to comply with other agreements in the Indenture or the Securities, subject to
notice and lapse of time; (iv) default under any bond, debenture, note or other
evidence of indebtedness for money borrowed of the Company or any Subsidiary
having an aggregate outstanding principal

                                      A-12
<PAGE>   77

amount of in excess of $25,000,000 (excluding such indebtedness of any
Subsidiary other than a Significant Subsidiary, all the indebtedness of which is
nonrecourse to the Company or any other Subsidiary), which default shall be with
respect to payment or shall have resulted in such indebtedness being
accelerated, without such indebtedness being discharged or such acceleration
having been rescinded or annulled, subject to notice and passage of time; and
(v) certain events of bankruptcy, insolvency or reorganization of the Company or
any Significant Subsidiary. If an Event of Default with respect to Securities of
this series shall occur and be continuing, all unpaid Issue Price plus accrued
Original Issue Discount through the acceleration date (or, if the Security has
been converted to an interest bearing debenture, the Restated Principal Amount
plus accrued and unpaid interest from the date of conversion to the acceleration
date) of the Securities of this series may be declared due and payable in the
manner and with the effect provided in the Indenture. If an Event of Default
occurs as a result of certain events of bankruptcy, insolvency or reorganization
of the Company, such specified amount of the Securities outstanding shall become
due and payable immediately without any declaration or other act on the part of
the Trustee or any Holder, all as and to the extent provided in the Indenture.

NO RECOURSE AGAINST OTHERS

         No recourse shall be had for the payment of the principal of or the
interest, if any, on this Security, for any claim based hereon, or otherwise in
respect hereof, or based on or in respect of the Indenture or any indenture
supplemental thereto, against any incorporator, shareholder, officer or
director, as such, past, present or future, of the Company or of any successor
corporation, whether by virtue of any constitution, statute or rule of law or by
the enforcement of any assessment of penalty or otherwise, all such liability
being, by acceptance hereof and as part of the consideration for the issue
hereof, expressly waived and released.

AUTHENTICATION

         This Security shall not be valid until the Trustee or an authenticating
agent manually signs the certificate of authentication on the other side of this
Security.

INDENTURE TO CONTROL; GOVERNING LAW

         In the case of any conflict between the provisions of this Security and
the Indenture, the provisions of the Indenture shall control.

         THE INDENTURE AND THE SECURITIES SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO THE
CONFLICTS OF LAW RULES OF SAID STATE.

                                      A-13
<PAGE>   78

ABBREVIATIONS AND DEFINITIONS

         Customary abbreviations may be used in the name of the Holder or an
assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the
entireties), JT TEN (= joint tenants with right of survivorship and not as
tenants in common),

CUST (= Custodian) and U/G/M/A (= Uniform Gifts to Minors Act).

         All terms defined in the Indenture and used in this Security but not
specifically defined herein are defined in the Indenture and are used herein as
so defined.

                                      A-14
<PAGE>   79

                                CONVERSION NOTICE

         To convert this Security into Common Stock of the Company, check the
box: [ ]

         To convert only part of this Security, state the Principal Amount to be
converted (must be $1,000 or a multiple of $1,000): $
                                                      -------------

         If you want the stock certificate made out in another person's name,
fill in the form below:

--------------------------------------------------------------------------------
                (Insert other person's soc. sec. or tax I.D. no.)

--------------------------------------------------------------------------------
            (Print or type other person's name, address and zip code)

Your Signature:                                   Date:
               ---------------------------------        ------------------------
(Sign exactly as your name appears on the other side of this Security)

*Signature guaranteed by:
                         -------------------------------------------------------

By:
   -------------------------------

---------

*        The signature must be guaranteed by an institution which is a member of
         one of the following recognized signature guaranty programs: (i) the
         Securities Transfer Agent Medallion Program (STAMP); (ii) the New York
         Stock Exchange Medallion Program (MSP); (iii) the Stock Exchange
         Medallion Program (SEMP); or (iv) such other guaranty program
         acceptable to the Trustee.

                                      A-15
<PAGE>   80

                 OPTION OF HOLDER TO ELECT PURCHASE ON CHANGE IN
                                     CONTROL

         If you want to elect to have this Security purchased, in whole or in
part, by the Company pursuant to Section 1601 of the Indenture, check the
following box: [ ]

         If you want to have only part of this Security purchased by the Company
pursuant to Section 1601 of the Indenture, state the Principal Amount you want
to be purchased (must be $1,000 or a multiple of $1,000): $
                                                           ---------------------

Your Signature:                                   Date:
               ---------------------------------        ------------------------
(Sign exactly as your name appears on the other side of this Security)

Signature guaranteed by:
                        --------------------------------------------------------

By:
   -------------------------------

----------

*        The signature must be guaranteed by an institution which is a member of
         one of the following recognized signature guaranty programs; (i) the
         Securities Transfer Agent Medallion Program (STAMP); (ii) the New York
         Stock Exchange Medallion Program (MSP); (iii) the Stock Exchange
         Medallion Program (SEMP); or (iv) such other guaranty program
         acceptable to the Trustee

                                      A-16
<PAGE>   81

                     SCHEDULE OF EXCHANGES OF SECURITIES(4)

         The following exchanges, redemptions, repurchases or conversions of a
part of this Global Security have been made:

<TABLE>
<CAPTION>
                               Amount of Decrease in               Amount of Increase in
                              Principal Amount of this            Principal Amount of the
  Date of Transaction             Global Security                     Global Security
  -------------------         ------------------------            -----------------------
<S>                           <C>                                 <C>
</TABLE>

----------

(4)      This schedule should be included only if the Security is a Global
         Security.

                                      A-17
<PAGE>   82

                  CERTIFICATE TO BE DELIVERED UPON EXCHANGE OR
              REGISTRATION OF TRANSFER OF RESTRICTED SECURITIES(5)

         Re:      Zero Coupon Convertible Debentures Due June 6, 2020 (the
                  "Securities") of Diamond Offshore Drilling, Inc.

         This certificate relates to $_________ principal amount at maturity of
Securities owned in (check applicable box)

         [ ] book-entry or

         [ ] definitive form

by _______________________________________ (the "Transferor").

         The Transferor has requested a Registrar or the Trustee to exchange or
register the transfer of such Securities.

         In connection with such request and in respect of each such Security,
the Transferor does hereby certify that the Transferor is familiar with
transfer restrictions relating to the Securities as provided in Section 102 of
the Indenture dated as of June 6, 2000 (the "Indenture"), between Diamond
Offshore Drilling, Inc. and The Chase Manhattan Bank.

         In connection with any transfer of any of the Securities evidenced by
this certificate occurring prior to the expiration of the period referred to in
Rule 144(k) under the Securities Act after the later of the date of original
issuance of such Securities and the last date, if any, on which such Securities
were owned by the Company or any Affiliate of the Company, the undersigned
confirms that such Securities are being transferred in accordance with its
terms:

CHECK ONE BOX BELOW

      (1)    [ ]    to the Company; or

      (2)    [ ]    pursuant to an effective registration statement under the
                    Securities Act of 1933; or

      (3)    [ ]    inside the United States to a "qualified institutional
                    buyer" (as defined in Rule 144A under the Securities Act of
                    1933) that purchases for its own account or for the account
                    of a qualified institutional buyer to whom notice

----------

(5)      This certificate should only be included if this Security is a Transfer
         Restricted Security.

                                      A-18
<PAGE>   83

                    is given that such transfer is being made in reliance on
                    Rule 144A, in each case pursuant to and in compliance with
                    Rule 144A under the Securities Act of 1933; or

      (4)    [ ]    outside the United States in an offshore transaction within
                    the meaning of Regulation S under the Securities Act in
                    compliance with Rule 904 under the Securities Act of 1933;
                    or

      (5)    [ ]    pursuant to another available exemption from registration
                    provided by Rule 144 under the Securities Act of 1933.

Unless one of the boxes is checked, the Trustee will refuse to register any of
the Securities evidenced by this certificate in the name of any person other
than the registered holder thereof; provided, however, that if box (4) or (5) is
checked, the Trustee may require, prior to registering any such transfer of the
Securities, such legal opinions, certifications and other information as the
Company has reasonably requested to confirm that such transfer is being made
pursuant to an exemption from, or in a transaction not subject to, the
registration requirements of the Securities Act of 1933, such as the exemption
provided by Rule 144 under such Act.

                                             -----------------------------------
                                             Signature

Signature Guarantee:

-----------------------------------          -----------------------------------
Signature must be guaranteed                 Signature

              TO BE COMPLETED BY PURCHASER IF (3) ABOVE IS CHECKED.

         The undersigned represents and warrants that it is purchasing this
Security for its own account or an account with respect to which it exercises
sole investment discretion and that it and any such account is a "qualified
institutional buyer" within the meaning of Rule 144A under the Securities Act of
1933, and is aware that the sale to it is being made in reliance on Rule 144A
and acknowledges that it has received such information regarding the Company as
the undersigned has requested pursuant to Rule 144A or has determined not to
request such information and that it is aware that the transferor is relying
upon the undersigned's foregoing representations in order to claim the exemption
from registration provided by Rule 144A.

Dated:
      -----------------------------          -----------------------------------
                                             NOTICE: To be executed by an
                                                     executive officer

                                      A-19

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