<PAGE>

                                                                     EXHIBIT 4.1

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                              QUANTA SERVICES, INC.

                                       and

                             WELLS FARGO BANK, N.A.,
                                     Trustee

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

                                    INDENTURE

                                   Dated as of

                                October 17, 2003

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

               4.50% CONVERTIBLE SUBORDINATED DEBENTURES DUE 2023

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                                TABLE OF CONTENTS

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                                    ARTICLE 1
                                   DEFINITIONS

Section 1.01. Definitions.......................................................      1

                                    ARTICLE 2
     ISSUE, DESCRIPTION, EXECUTION, REGISTRATION AND EXCHANGE OF DEBENTURES

Section 2.01. Designation Amount and Issue of Debentures........................     13
Section 2.02. Form of Debentures................................................     13
Section 2.03. Date and Denomination of Debentures; Payments of Interest.........     14
Section 2.04. Execution of Debentures...........................................     15
Section 2.05. Exchange and Registration of Transfer of Debentures; Restrictions
                on Transfer.....................................................     16
Section 2.06. Mutilated, Destroyed, Lost or Stolen Debentures...................     22
Section 2.07. Temporary Debentures..............................................     23
Section 2.08. Cancellation of Debentures........................................     23
Section 2.09. CUSIP Numbers.....................................................     23

                                    ARTICLE 3
                     REDEMPTION AND REPURCHASE OF DEBENTURES

Section 3.01. Company's Right to Redeem.........................................     24
Section 3.02. Notice of Optional Redemption; Selection of Debentures............     24
Section 3.03. Payment of Debentures Called for Redemption by the Company........     25
Section 3.04. Conversion Arrangement on Call for Redemption.....................     26
Section 3.05. Repurchase of Debentures by the Company at Option of Holders upon
                a Fundamental Change............................................     27
Section 3.06. Repurchase of Debentures by the Company at Option of Holders on
                Specified Dates.................................................     29
Section 3.07. Company's Right to Elect Manner of Payment of Repurchase Price....     32
Section 3.08. Conditions and Procedures for Repurchase at Option of Holders.....     34

                                    ARTICLE 4
                           SUBORDINATION OF DEBENTURES

Section 4.01. Agreement to Subordinate..........................................     37
Section 4.02. Payment Over of Proceeds Upon Dissolution, Etc....................     37
Section 4.03. No Payment When Senior Indebtedness of the Company in Default.....     38
Section 4.04. Payment Permitted If No Default...................................     39
Section 4.05. Subrogation to Rights of Holders of Designated Senior
                Indebtedness of the Company.....................................     39
Section 4.06. Provisions Solely to Define Relative Rights.......................     40
Section 4.07. Trustee to Effectuate Subordination...............................     40
Section 4.08. No Waiver of Subordination Provisions.............................     40
Section 4.09. Notice to Trustee.................................................     41
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Section 4.10. Reliance on Judicial Order or Certificate of Liquidating Agent....     41
Section 4.11. Trustee Not Fiduciary for Holders of Senior Indebtedness of the
                Company.........................................................     42
Section 4.12. Rights of Trustee as Holder of Senior Indebtedness of the
                Company; Preservation of Trustee's Rights.......................     42
Section 4.13. Article Applicable to Paying Agents...............................     42

                                    ARTICLE 5
                       PARTICULAR COVENANTS OF THE COMPANY

Section 5.01. Payment of Principal and Interest.................................     42
Section 5.02. Maintenance of Office or Agency...................................     42
Section 5.03. Appointments to Fill Vacancies in Trustee's Office................     43
Section 5.04. Provisions as to Paying Agent.....................................     43
Section 5.05. Existence.........................................................     44
Section 5.06. Rule 144A Information Requirement.................................     44
Section 5.07. Stay, Extension and Usury Laws....................................     45
Section 5.08. Compliance Certificate............................................     45
Section 5.09. Additional Amounts Notice.........................................     45

                                    ARTICLE 6
       DEBENTUREHOLDERS' LISTS AND REPORTS BY THE COMPANY AND THE TRUSTEE

Section 6.01. Debentureholders' Lists...........................................     45
Section 6.02. Preservation and Disclosure of Lists..............................     46
Section 6.03. Reports by Trustee................................................     46
Section 6.04. Reports by the Company............................................     46

                                    ARTICLE 7
      REMEDIES OF THE TRUSTEE AND DEBENTUREHOLDERS ON AN EVENT OF DEFAULT

Section 7.01. Events of Default.................................................     47
Section 7.02. Payments of Debentures on Default; Suit Therefor..................     49
Section 7.03. Application of Monies Collected by Trustee........................     51
Section 7.04. Proceedings by Debentureholder....................................     51
Section 7.05. Proceedings by Trustee............................................     52
Section 7.06. Remedies Cumulative and Continuing................................     52
Section 7.07. Direction of Proceedings and Waiver of Defaults by Majority of
                Debentureholders................................................     52
Section 7.08. Notice of Defaults................................................     53
Section 7.09. Undertaking to Pay Costs..........................................     53

                                    ARTICLE 8
                                   THE TRUSTEE

Section 8.01. Duties and Responsibilities of Trustee............................     54
Section 8.02. Reliance on Documents, Opinions, Etc..............................     55
Section 8.03. No Responsibility for Recitals, Etc...............................     56
Section 8.04. Trustee, Paying Agents, Conversion Agents or Registrar May Own
                Debentures......................................................     57
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                                       ii

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Section 8.05. Monies to Be Held in Trust........................................     57
Section 8.06. Compensation and Expenses of Trustee..............................     57
Section 8.07. Officers' Certificate as Evidence.................................     58
Section 8.08. Conflicting Interests of Trustee..................................     58
Section 8.09. Eligibility of Trustee............................................     58
Section 8.10. Resignation or Removal of Trustee.................................     58
Section 8.11. Acceptance by Successor Trustee...................................     59
Section 8.12. Succession by Merger..............................................     60
Section 8.13. Preferential Collection of Claims.................................     60

                                    ARTICLE 9
                              THE DEBENTUREHOLDERS

Section 9.01. Action by Debentureholders........................................     60
Section 9.02. Proof of Execution by Debentureholders............................     61
Section 9.03. Who Are Deemed Absolute Owners....................................     61
Section 9.04. Company-owned Debentures Disregarded..............................     61
Section 9.05. Revocation of Consents, Future Holders Bound......................     62

                                   ARTICLE 10
                          MEETINGS OF DEBENTUREHOLDERS

Section 10.01. Purpose of Meetings..............................................     62
Section 10.02. Call of Meetings by Trustee......................................     62
Section 10.03. Call of Meetings by Company or Debentureholders..................     63
Section 10.04. Qualifications for Voting........................................     63
Section 10.05. Regulations......................................................     63
Section 10.06. Voting...........................................................     64
Section 10.07. No Delay of Rights by Meeting....................................     64

                                   ARTICLE 11
                             SUPPLEMENTAL INDENTURES

Section 11.01. Supplemental Indentures Without Consent of Debentureholders......     64
Section 11.02. Supplemental Indenture with Consent of Debentureholders..........     66
Section 11.03. Effect of Supplemental Indenture.................................     67
Section 11.04. Notation on Debentures...........................................     67
Section 11.05. Evidence of Compliance of Supplemental Indenture to Be Furnished
                to Trustee......................................................     68

                                   ARTICLE 12
                CONSOLIDATION, MERGER, SALE, CONVEYANCE AND LEASE

Section 12.01. Company May Consolidate on Certain Terms.........................     68
Section 12.02. Successor to Be Substituted......................................     68
Section 12.03. Opinion of Counsel to Be Given Trustee...........................     69
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                                   ARTICLE 13
                     SATISFACTION AND DISCHARGE OF INDENTURE

Section 13.01. Discharge of Indenture...........................................     69
Section 13.02. Paying Agent to Repay Monies Held................................     70
Section 13.03. Return of Unclaimed Monies.......................................     70

                                   ARTICLE 14
        IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS AND DIRECTORS

Section 14.01. Indenture and Debentures Solely Corporate Obligations............     70

                                   ARTICLE 15
                            CONVERSION OF DEBENTURES

Section 15.01. Right to Convert.................................................     70
Section 15.02. Exercise of Conversion Privilege; Issuance of Common Stock on
                Conversion; No Adjustment for Interest or Dividends; Settlement
                of Cash or Common Stock upon Conversion.........................     73
Section 15.03. Cash Payments in Lieu of Fractional Shares.......................     77
Section 15.04. Conversion Rate..................................................     77
Section 15.05. Adjustment of Conversion Rate....................................     77
Section 15.06. Effect of Reclassification, Consolidation, Merger or Sale........     83
Section 15.07. Taxes on Shares Issued...........................................     84
Section 15.08. Reservation of Shares, Shares to Be Fully Paid; Compliance with
                Governmental Requirements; Listing of Common Stock..............     84
Section 15.09. Responsibility of Trustee........................................     85
Section 15.10. Notice to Holders Prior to Certain Actions.......................     85
Section 15.11. Stockholder Rights Plans.........................................     86

                                   ARTICLE 16
                            MISCELLANEOUS PROVISIONS

Section 16.01. Confidentiality Exception........................................     86
Section 16.02. Provisions Binding on Company's Successors.......................     87
Section 16.03. Official Acts by Successor Corporation...........................     87
Section 16.04. Addresses for Notices, Etc.......................................     87
Section 16.05. Governing Law....................................................     87
Section 16.06. Evidence of Compliance with Conditions Precedent, Certificates
                to Trustee......................................................     87
Section 16.07. Legal Holidays...................................................     88
Section 16.08. Company Responsible for Making Calculations......................     88
Section 16.09. Trust Indenture Act..............................................     88
Section 16.10. No Security Interest Created.....................................     89
Section 16.11. Benefits of Indenture............................................     89
Section 16.12. Table of Contents, Headings, Etc.................................     89
Section 16.13. Authenticating Agent.............................................     89
Section 16.14. Execution in Counterparts........................................     90
Section 16.15. Severability.....................................................     90
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                                       iv

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Exhibit A         Form of Debenture                                          A-1

                                       v

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                                    INDENTURE

         INDENTURE dated as of October 17, 2003 between Quanta Services, Inc., a
Delaware corporation (hereinafter called the "Company"), having its principal
office at 1360 Post Oak Boulevard, Suite 2100, Houston, TX 77056, and Wells
Fargo Bank, N.A., a National banking association (hereinafter called the
"TRUSTEE").

                                   WITNESSETH:

         WHEREAS, for its lawful corporate purposes, the Company has duly
authorized the issue of its 4.50% Convertible Subordinated Debentures due 2023
(hereinafter called the "DEBENTURES"), in an aggregate principal amount not to
exceed $270,000,000, and, to provide the terms and conditions upon which the
Debentures are to be authenticated, issued and delivered, the Company has duly
authorized the execution and delivery of this Indenture.

         WHEREAS, the Debentures, the certificate of authentication to be borne
by the Debentures, a form of assignment, a form of fundamental change repurchase
election, a form of Company repurchase election and a form of conversion notice
to be borne by the Debentures are to be substantially in the forms hereinafter
provided for.

         WHEREAS, all acts and things necessary to make the Debentures, when
executed by the Company and authenticated and delivered by the Trustee or a duly
authorized authenticating agent, as in this Indenture provided, the valid,
binding and legal obligations of the Company, and to constitute this Indenture a
valid agreement according to its terms, have been done and performed, and the
execution of this Indenture and the issue hereunder of the Debentures have in
all respects been duly authorized. In addition, all things necessary to duly
authorize the issuance of the Common Stock of the Company initially issuable
upon the conversion of the Debentures, and to duly reserve for issuance the
number of shares of Common Stock initially issuable upon such conversion have
been done.

         NOW, THEREFORE, THIS INDENTURE WITNESSETH:

         That in order to declare the terms and conditions upon which the
Debentures are, and are to be, authenticated, issued and delivered, and in
consideration of the premises and of the purchase and acceptance of the
Debentures by the holders thereof, the Company covenants and agrees with the
Trustee for the equal and proportionate benefit of the respective holders from
time to time of the Debentures (except as otherwise provided below), as follows:

                                   ARTICLE 1
                                   DEFINITIONS

Section 1.01. Definitions. The terms defined in this Section 1.01 (except as
herein otherwise expressly provided or unless the context otherwise requires)
for all purposes of this Indenture and of any indenture supplemental hereto
shall have the respective meanings specified in this Section 1.01. All other
terms used in this Indenture that are defined in the Trust Indenture Act or
which are by reference therein defined in the Securities Act (except as herein
otherwise expressly provided or unless the context otherwise requires) shall
have the meanings assigned to such terms in the Trust Indenture Act and in the
Securities Act as in force at the date of the

<PAGE>

execution of this Indenture. The words "HEREIN", "HEREOF", "HEREUNDER" and words
of similar  import refer to this  Indenture as a whole and not to any particular
Article, Section or other Subdivision. The terms defined in this Article include
the plural as well as the singular.

         "ADDITIONAL AMOUNTS" has the meaning specified for "Liquidated Damages"
in Section 3(a) of the Registration Rights Agreement.

         "ADDITIONAL AMOUNTS NOTICE" has the meaning specified in Section 5.09.

         "ADJUSTMENT EVENT" has the meaning specified in Section 15.05(m).

         "AGENT MEMBERS" has the meaning specified in Section 2.05(b)(v).

         "AFFILIATE" of any specified Person means any other Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person. For the purposes of this definition,
"CONTROL", when used with respect to any specified Person, means the power to
direct or cause the direction of the management and policies of such Person,
directly or indirectly, whether through the ownership of voting securities, by
contract or otherwise, and the terms "CONTROLLING" and "controlled" have
meanings correlative to the foregoing.

         "BANKRUPTCY LAW" means Title 11, United States Bankruptcy Code of 1978,
as amended, or any similar United States federal or state law relating to the
bankruptcy, insolvency, receivership, winding-up, liquidation, reorganization or
relief of debtors or any amendment to, succession to or change in any such law.

         "BOARD OF DIRECTORS" means the Board of Directors of the Company or a
committee of such Board duly authorized to act for it hereunder.

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

         "BUSINESS DAY" means any day, other than a Saturday or Sunday, that is
neither a legal holiday nor a day on which commercial banks are authorized or
required by law, regulation or executive order to close in The City of New York.

         "CAPITAL STOCK" of any Person means any and all shares (including
ordinary shares underlying any American Depositary Shares), interests,
participations or other equivalents however designated of corporate stock or
other equity participations, including partnership interests, whether general or
limited, of such Person and any rights (other than debt securities convertible
or exchangeable into an equity interest), warrants or options to acquire an
equity interest in such Person.

         "CASH" has the meaning specified in Section 3.07(a).

         "CASH AMOUNT" has the meaning specified in Section 15.02(h).

                                       2

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         "CASH SETTLEMENT AVERAGING PERIOD" has the meaning specified in Section
15.02(g)(i).

         "CASH SETTLEMENT NOTICE PERIOD" has the meaning specified in
15.02(g)(i).

         "COMMISSION" means the Securities and Exchange Commission, as from time
to time constituted under the Exchange Act, or, if at any time after the
execution of this Indenture such Commission is not existing and performing the
duties now assigned to it under the Trust Indenture Act, then the body
performing such duties at such time.

         "COMMON STOCK" means any stock of any class of the Company which has no
preference in respect of dividends or of amounts payable in the event of any
voluntary or involuntary liquidation, dissolution or winding up of the Company
and which is not subject to redemption by the Company, and includes the rights
evidenced by such stock to the extent provided in the Rights Agreement dated
March 8, 2000 (and as amended prior to the date hereof) between the Company and
American Stock Transfer & Trust Company. Subject to the provisions of Section
15.06, however, shares issuable on conversion of Debentures shall include only
shares of the class designated as common stock of the Company at the date of
this Indenture (namely, the Common Stock, par value $.00001) or shares of any
class or classes resulting from any reclassification or reclassifications
thereof and which have no preference in respect of dividends or of amounts
payable in the event of any voluntary or involuntary liquidation, dissolution or
winding up of the Company and which are not subject to redemption by the
Company; provided that if at any time there shall be more than one such
resulting class, the shares of each such class then so issuable on conversion
shall be substantially in the proportion which the total number of shares of
such class resulting from all such reclassifications bears to the total number
of shares of all such classes resulting from all such reclassifications.

         "COMPANY" means the corporation named as the "Company" in the first
paragraph of this Indenture, and, subject to the provisions of Article 12 and
Section 15.06, shall include its successors and assigns.

         "COMPANY REPURCHASE DATE" has the meaning specified in Section 3.06(a).

         "COMPANY REPURCHASE ELECTION" has the meaning specified in Section
3.06(c)(i).

         "COMPANY REPURCHASE NOTICE" has the meaning specified in Section
3.06(b).

         "COMPANY REPURCHASE PRICE" has the meaning specified in Section
3.06(a).

         "CONVERSION AGENT" means the Trustee or such other office or agency
designated by the Company where Debentures may be presented for conversion.

         "CONVERSION DATE" has the meaning specified in Section 15.02.

         "CONVERSION OBLIGATION" has the meaning specified in Section
15.02(g)(i).

         "CONVERSION PRICE" as of any day means $1,000 divided by the Conversion
Rate as of such date and rounded to the nearest cent. The Conversion Price shall
initially be $11.14 per share of Common Stock.

                                       3

<PAGE>

         "CONVERSION RATE" has the meaning specified in Section 15.04.

         "CONVERSION RETRACTION PERIOD" has the meaning specified in Section
15.02(g)(i).

         "CORPORATE TRUST OFFICE" or other similar term means the designated
office of the Trustee at which at any particular time its corporate trust
business as it relates to this Indenture shall be administered, which office is,
at the date as of which this Indenture is dated, located at 505 Main Street,
Suite 301, Forth Worth, Texas 76102.

         "CURRENT MARKET PRICE" per share of Common Stock means, with respect to
any date of determination, the average of the Last Reported Sale Price of the
Common Stock for the ten (10) consecutive Trading Days ending not later than the
earlier of the date of determination and the day before the Ex-Dividend Date
with respect to the issuance or distribution requiring such computation. If
another issuance or distribution to which Section 15.05 applies occurs during
the period applicable for calculating "CURRENT MARKET PRICE" pursuant to this
definition, "CURRENT MARKET PRICE" shall be calculated for such period in a
manner determined by the Board of Directors to reflect the impact of such
issuance, distribution, subdivision or combination on the Last Reported Sale
Price of the Common Stock during such period.

         "CUSTODIAN" means Wells Fargo Bank, N.A., a National banking
association, as custodian with respect to the Debentures in global form, or any
successor entity thereto.

         "DEBENTURE" or "DEBENTURES" means any Debenture or Debentures, as the
case may be, authenticated and delivered under this Indenture, including any
Global Debenture.

         "DEBENTURE REGISTER" has the meaning specified in Section 2.05.

         "DEBENTURE REGISTRAR" has the meaning specified in Section 2.05.

         "DEBENTUREHOLDER" or "HOLDER" as applied to any Debenture, or other
similar terms (but excluding the term "BENEFICIAL holder"), means any Person in
whose name a particular Debenture is registered at the time on the Debenture
Registrar's books.

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

         "DEFAULTED INTEREST" has the meaning specified in Section 2.03.

         "DEPOSITARY" means the clearing agency registered under the Exchange
Act that is designated to act as the Depositary for the Global Debentures. The
Depository Trust Company shall be the initial Depositary, until a successor
shall have been appointed and become such pursuant to the applicable provisions
of this Indenture, and thereafter, "Depositary" shall mean or include such
successor.

         "DESIGNATED SENIOR INDEBTEDNESS" means senior indebtedness under the
Senior Credit Agreement and the Senior Secured Note Agreement and the Company's
obligations under any other particular senior indebtedness that expressly
provides that such senior indebtedness shall be "Designated Senior Indebtedness"
of the Company for the purposes of this Indenture.

                                       4

<PAGE>

         "DETERMINATION DATE" has the meaning specified in Section 15.05(m).

         "EVENT OF DEFAULT" has the meaning specified in Section 7.01.

         "EXCHANGE ACT" means the Securities Exchange Act of 1934, as amended,
and the rules and regulations promulgated thereunder, as in effect from time to
time.

         "EX-DIVIDEND DATE" means, with respect to any issuance or distribution
on shares of Common Stock, the first date on which the shares of Common Stock
trade regular way on the principal securities market on which the shares of
Common Stock are then traded without the right to receive such issuance or
distribution.

         "EXPIRATION TIME" has the meaning specified in Section 15.05(f).

         "FAIR MARKET VALUE" means, with respect to any asset or property, the
sale value that would be obtained in an arm's-length transaction between an
informed and willing seller under no compulsion to sell and an informed and
willing buyer under no compulsion to buy. Unless otherwise indicated, Fair
Market Value shall be determined in good faith by the Board of Directors.

         "FINAL NOTICE DATE" has the meaning specified in Section 15.02(g).

         "FORM OF CONVERSION NOTICE" has the meaning specified in Section
15.02(a).

         "FUNDAMENTAL CHANGE" means the occurrence of any of the following:

                  (i)      a "person" or "group", within the meaning of Section
         13(d) of the Exchange Act other than the Company, its subsidiaries or
         its or their employee benefit plans, files a Schedule TO or any other
         schedule, form or report under the Exchange Act disclosing that such
         person or group has become the direct or indirect ultimate "beneficial
         owner", as defined in Rule 13d-3 under the Exchange Act, of more than
         50% of the total voting power of all shares of the Company's capital
         stock that are entitled to vote generally in the election of directors;
         or

                  (ii)     consummation of any share exchange, consolidation or
         merger of the Company or any sale, lease or other transfer in one
         transaction or a series of transactions of all or substantially all of
         the consolidated assets of the Company and its subsidiaries, taken as a
         whole, to any person other than the Company or one or more of its
         subsidiaries, pursuant to which the Common Stock will be converted into
         cash, securities or other property; provided, however, that a
         transaction where the holders of the Company's voting capital stock
         immediately prior to such transaction have, directly or indirectly,
         more than 50% of the aggregate voting power of all shares of capital
         stock of the continuing or surviving corporation or transferee entitled
         to vote generally in the election of directors immediately after such
         event shall not be a Fundamental Change.

                                       5

<PAGE>

         A Fundamental Change will not be deemed to have occurred in respect of
either of the foregoing, however, if either:

                  (i)      the Last Reported Sale Price of the Common Stock for
         any five (5) Trading Days within the ten (10) consecutive Trading Days
         ending immediately before the later of the Fundamental Change or the
         public announcement thereof equals or exceeds 105% of the Conversion
         Price of the Debentures immediately before the Fundamental Change or
         the public announcement thereof, or

                  (ii)     at least 90% of the consideration, excluding cash
         payments for fractional shares, in the transaction or transactions
         constituting the Fundamental Change consists of shares of capital stock
         traded on a national securities exchange or quoted on the Nasdaq
         National Market or which will be so traded or quoted when issued or
         exchanged in connection with a Fundamental Change (these securities
         being referred to as "PUBLICLY TRADED SECURITIES") and as a result of
         this transaction or transactions the Debentures become convertible into
         such publicly traded securities, excluding cash payments for fractional
         shares.

         "FUNDAMENTAL CHANGE REPURCHASE DATE" has the meaning specified in
Section 3.05(a).

         "FUNDAMENTAL CHANGE REPURCHASE ELECTION" has the meaning specified in
Section 3.05(c)(i).

         "FUNDAMENTAL CHANGE REPURCHASE NOTICE" has the meaning specified in
Section 3.05(b).

         "FUNDAMENTAL CHANGE REPURCHASE PRICE" has the meaning provided in
Section 3.05(a).

         "GLOBAL DEBENTURE" has the meaning specified in Section 2.02.

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

         "INDEBTEDNESS" means, with respect to any Person, without duplication:

                  (1)      all indebtedness, obligations and other liabilities
         of such Person for borrowed money, including commitment or standby
         fees, enforcement expenses, collateral protection expenses and other
         reimbursement indemnity obligations with respect to such indebtedness,
         overdrafts, foreign exchange contracts, currency exchange agreements,
         interest rate protection agreements, and any loans or advances from
         banks, or evidenced by bonds, debentures, notes or similar instruments,
         other than any account payable or other accrued current liability or
         obligation of such Person incurred in the ordinary course of business
         in connection with the obtaining of materials or services;

                                       6

<PAGE>

                  (2)      obligations of such Person with respect to letters of
         credit, bank guarantees or bankers' acceptances;

                  (3)      obligations of such Person in respect of leases
         required in conformity with generally accepted accounting principles to
         be accounted for as capitalized lease obligations;

                  (4)      all obligations and other liabilities of such Person
         under any lease or related document in connection with the lease of
         real property that provides that such Person is contractually obligated
         to purchase or cause a third party to purchase the leased property and
         thereby guarantee a minimum residual value of the leased property to
         the lessor and such Person's obligations under the lease or related
         document to purchase or to cause a third party to purchase the leased
         property;

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

                  (6)      all direct or indirect guarantees or similar
         agreements in respect of such Person's obligations or liabilities to
         purchase, acquire or otherwise assure a creditor against loss in
         respect of, indebtedness, obligations or liabilities of others of the
         type described in paragraphs (1) through (5) above;

                  (7)      any obligations of such Person described in
         paragraphs (1) to (5) above secured by any mortgage, pledge, lien or
         other encumbrance existing on property which is owned or held by such
         Person; and

                  (8)      any renewals, extensions, refundings, refinancings,
         restructurings, amendments or modifications to paragraphs (1) through
         (7) above.

         "INDENTURE" means this instrument as originally executed or, if amended
or supplemented as herein provided, as so amended or supplemented.

         "INITIAL PURCHASERS" means Banc of America Securities LLC and J.P.
Morgan Securities Inc.

         "INTEREST" means, when used with respect to the Debentures, any
interest payable under the terms of the Debentures and Additional Amounts, if
any, payable under the terms of the Registration Rights Agreement.

         "INTEREST PAYMENT DATE" means April 1 and October 1 of each year,
commencing April 1, 2004.

          "LAST REPORTED SALE PRICE" of the Common Stock on any date means the
closing sale price per share (or if no closing sale price is reported, the
average of the bid and asked prices or, if more than one in either case, the
average of the average bid and the average asked prices) on that date as
reported in 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

                                       7

<PAGE>

national or regional securities exchange, as reported by the Nasdaq National
Market. If the Common Stock is not listed for trading on a U.S. national or
regional securities exchange on the relevant date, the "LAST REPORTED SALE
PRICE" will be the last quoted bid price for the Common Stock in the
over-the-counter market on the relevant date as reported by the National
Quotation Bureau Incorporated or similar organization. If the Common Stock is
not so quoted, the "LAST REPORTED SALE PRICE" will be the average of the
mid-point of the last bid and asked prices for the Common Stock on the relevant
date quoted by each of at least three independent nationally recognized
investment banking firms selected by the Company for this purpose.

         "LIEN" means, with respect to any asset, mortgage, lien, pledge,
charge, security interest or encumbrance of any kind in respect of such asset
given to secure Indebtedness, whether or not filed, recorded or otherwise
perfected under applicable law (including any conditional sale or other title
retention agreement, any lease in the nature thereof, any option or other
agreement to sell or give a security interest in and any filing of or agreement
to give any financing statement under the Uniform Commercial Code (or equivalent
statutes) of any jurisdiction with respect to any such lien, pledge, charge or
security interest).

         "MARKET PRICE" means, with respect to any Repurchase Date or other date
of determination, the average of the Last Reported Sale Price of the Common
Stock for the twenty (20) consecutive Trading Days ending on the third Business
Day prior to the applicable Repurchase Date or date of determination, as the
case may be (or, if such third Business Day prior to the applicable Repurchase
Date or date of determination, as the case may be, is not a Trading Day, then
ending on the last Trading Day prior to such third Business Day), appropriately
adjusted to take into account the occurrence, during the period commencing on
the first Trading Day during the period of twenty (20) consecutive Trading Days
and ending on the applicable Repurchase Date or date of determination, as the
case may be, of any event described in Section 15.05 or Section 15.06.

         "NON-ELECTING SHARE" has the meaning specified in Section 15.06.

         "OFFICERS' CERTIFICATE", when used with respect to the Company, means a
certificate signed by any two of the Chairman of the Board, the Chief Executive
Officer, the Chief Operating Officer, the President, the Chief Financial
Officer, any Vice President (whether or not designated by a number or numbers or
word or words added before or after the title "Vice President"), the Treasurer
or the Secretary of the Company.

         "OPINION OF COUNSEL" means an opinion in writing signed by legal
counsel, who may be an employee of or counsel to the Company, or other counsel
reasonably acceptable to the Trustee.

         "ORIGINAL ISSUANCE DATE" means the date on which the Debentures are
first authenticated and delivered under this Indenture.

                                       8

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         "OUTSTANDING", when used with reference to Debentures and subject to
the provisions of Section 9.04, means, as of any particular time, all Debentures
authenticated and delivered by the Trustee under this Indenture, except:

                  (a)      Debentures theretofore canceled by the Trustee or
         delivered to the Trustee for cancellation;

                  (b)      Debentures, or portions thereof, (i) for the
         redemption of which monies in the necessary amount shall have been
         deposited in trust with the Trustee or with any Paying Agent (other
         than the Company) or (ii) which shall have been otherwise discharged in
         accordance with Article 13;

                  (c)      Debentures in lieu of which, or in substitution for
         which, other Debentures shall have been authenticated and delivered
         pursuant to the terms of Section 2.06; and

                  (d)      Debentures converted into Common Stock pursuant to
         Article 15 and Debentures deemed not outstanding pursuant to Article 3.

         "PAYING AGENT" means the Trustee or such other office or agency
designated by the Company where Debentures may be presented for payment.

         "PAYMENT BLOCKAGE PERIOD" has the meaning specified in Section 4.03.

         "PAYMENT DEFAULT" has the meaning specified in Section 4.03.

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

         "PORTAL MARKET" means The PORTAL Market operated by the National
Association of Securities Dealers, Inc. or any successor thereto.

         "PREDECESSOR DEBENTURE" of any particular Debenture means every
previous Debenture evidencing all or a portion of the same debt as that
evidenced by such particular Debenture, and, for the purposes of this
definition, any Debenture authenticated and delivered under Section 2.06 in lieu
of a lost, destroyed or stolen Debenture shall be deemed to evidence the same
debt as the lost, destroyed or stolen Debenture that it replaces.

         "PRINCIPAL VALUE CONVERSION" has the meaning specified in Section
15.01(b).

         "PROCEEDING" has the meaning specified in Section 4.02.

         "PURCHASED SHARES" has the meaning specified in Section 15.05(f).

         "REDEMPTION DATE" has the meaning specified in Section 3.02(a).

         "REDEMPTION NOTICE" has the meaning specified in Section 3.02(a).

         "REDEMPTION PRICE" has the meaning specified in Section 3.01.

                                       9

<PAGE>

         "REGISTRATION RIGHTS AGREEMENT" means the Registration Rights
Agreement, dated as of October 17, 2003, between the Company and the Initial
Purchasers, as amended from time to time in accordance with its terms.

         "REGULAR RECORD DATE" means, with respect to each Interest Payment
Date, the close of business on the March 15 or September 15 preceding such
Interest Payment Date (whether or not a Business Day).

         "REPURCHASE DATE" means the Fundamental Change Repurchase Date or the
Company Repurchase Date, as the context requires.

         "REPURCHASE ELECTION" means the Fundamental Change Repurchase Election
or the Company Repurchase Election, as the context requires.

         "REPURCHASE NOTICE" means the Fundamental Change Repurchase Notice or
the Company Repurchase Notice, as the context requires.

         "REPURCHASE PRICE" means the Fundamental Change Repurchase Price or the
Company Repurchase Price, as the context requires.

         "RESPONSIBLE OFFICER" means, when used with respect to the Trustee, any
officer within the corporate trust department of the Trustee with direct
responsibility for the administration of this Indenture and also means, with
respect to a particular corporate trust matter, any other officer to whom such
matter is referred because of such person's knowledge of or any familiarity with
the particular subject.

         "RESTRICTED SECURITIES" has the meaning specified in Section 2.05(c).

         "RULE 144A" means Rule 144A as promulgated under the Securities Act.

         "SECURITIES ACT" means the Securities Act of 1933, as amended, and the
rules and regulations promulgated thereunder, as in effect from time to time.

         "SECURITIES PAYMENT" has the meaning specified in Section 4.02.

         "SENIOR CREDIT AGREEMENT" means the Third Amended and Restated Secured
Credit Agreement, dated as of June 14, 1999, among the Company, the lenders
named therein and Bank of America, N.A., as administrative agent, including any
debentures, guarantees, collateral documents, instruments and agreements
executed in connection therewith, and in each case as

                                       10

<PAGE>

amended (including any amendment and restatement thereof), modified, extended,
renewed, refunded, substituted or replaced or refinanced from time to time,
including any agreement extending the maturity of, refinancing, replacing or
otherwise restructuring (including increasing the amount of available borrowings
thereunder or adding subsidiaries of the Company as additional borrowers or
guarantors thereunder), all or any portion of the Indebtedness under such
agreement or any successor or replacement agreement and whether by the same or
any other agents, creditor, lender or group of creditors or lenders.

         "SENIOR INDEBTEDNESS" means the principal, premium, if any, interest,
including any interest accruing after bankruptcy, and rent or termination
payments on or other amounts due on the Company's current or future
Indebtedness, whether created, incurred, assumed, guaranteed or in effect
guaranteed by the Company, but only to the extent that the same is not treated
as "unsecured indebtedness" for purposes of section 279 of the Internal Revenue
Code. For the avoidance of doubt, all amounts owing by the Company under the
Senior Credit Agreement and the Senior Secured Note Agreement constitute "SENIOR
INDEBTEDNESS".

         Notwithstanding the foregoing, "SENIOR INDEBTEDNESS" shall not include:

         (a)      Indebtedness that expressly provides that it shall not be
                  senior in right of payment to the Debentures or expressly
                  provides that it is on the same basis or junior to the
                  Debentures;

         (b)      Indebtedness of the Company to any of its Subsidiaries; and

         (c)      the Debentures.

         "SENIOR NONMONETARY DEFAULT" has the meaning specified in Section
4.03.

         "SENIOR SECURED NOTE AGREEMENT" means the Note Purchase Agreement,
dated as of March 1, 2000, among the Company and the lenders named therein,
including any notes, guarantees, collateral documents, instruments and
agreements executed in connection therewith, and in each case as amended
(including any amendment and restatement thereof), modified, extended, renewed,
refunded, substituted or replaced or refinanced from time to time, including any
agreement extending the maturity of, refinancing, replacing or otherwise
restructuring (including increasing the amount of available borrowings
thereunder or adding subsidiaries of the Company as additional borrowers or
guarantors thereunder) all or any portion of the Indebtedness under such
agreement or any successor or replacement agreement and whether by the same or
any other agents, creditor, lender or group of creditors or lenders.

         "SPECIAL RECORD DATE" has the meaning specified in Section 2.03.

         "SPIN-OFF MARKET PRICE" per share of Common Stock of the Company or the
capital stock of, or similar equity interests in, a subsidiary or other business
unit of the Company on any day means the average of the daily Last Reported Sale
Price of the Common Stock or such capital stock or similar equity interests for
the twenty (20) consecutive Trading Days commencing on and including the fifth
Trading Day after the Ex-Dividend Date with respect to the issuance or
distribution requiring such computation.

                                       11

<PAGE>

         "STATED MATURITY" means October 1, 2023.

         "STOCK RECORD DATE" means, with respect to any dividend, distribution
or other transaction or event in which the holders of Common Stock have the
right to receive any cash, securities or other property or in which the Common
Stock (or other applicable security) is exchanged for or converted into any
combination of cash, securities or other property, the date fixed for
determination of stockholders entitled to receive such cash, securities or other
property (whether such date is fixed by the Board of Directors or by statute,
contract or otherwise).

         "SUBSIDIARY" means, with respect to any Person, (a) any corporation,
association or other business entity of which more than 50% of the total voting
power of shares of capital stock or other equity interest entitled (without
regard to the occurrence of any contingency) to vote in the election of
directors, managers or trustees thereof is at the time owned or controlled,
directly or indirectly, by such Person or one or more of the other subsidiaries
of that Person (or a combination thereof) and (b) any partnership (i) the sole
general partner or managing general partner of which is such Person or a
subsidiary of such Person or (ii) the only general partners of which are such
Person or of one or more subsidiaries of such Person (or any combination
thereof).

         "TRADING DAY" means a day during which trading in securities generally
occurs on the New York Stock Exchange or, if the applicable security is not
listed on the New York Stock Exchange, on the principal other national or
regional securities exchange on which the applicable security is then listed or,
if the applicable security is not listed on a national or regional securities
exchange, on the National Association of Securities Dealers Automated Quotation
System or, if the applicable security is not quoted on the National Association
of Securities Dealers Automated Quotation System, on the principal other market
on which the applicable security is then traded (provided that no day on which
trading of the applicable security is suspended on such exchange or other
trading market will count as a trading day).

         "TRADING PRICE" means, as of any date of determination, the average of
the secondary market bid quotations obtained by the Trustee for $5,000,000
principal amount of Debentures at approximately 3:30 p.m., New York City time,
on such determination date from three independent nationally recognized
securities dealers (none of which shall be an Affiliate of the Company) in The
City of New York (or such other place that may be determined from time to time
by the Company) selected by the Company; provided, however, if at least three
such bids cannot reasonably be obtained by the Trustee, but two such bids are
obtained, then the average of the two bids shall be used, and if only one such
bid can reasonably be obtained by the Trustee, that one bid shall be used. If
the Trustee cannot reasonably obtain at least one bid for $5,000,000 principal
amount of Debentures from an independent nationally recognized securities dealer
or in the reasonable judgment of the Company, the bid quotations are not
indicative of the secondary market value of the Debentures, then the Trading
Price per $1,000 principal amount of Debentures will be deemed to be less than
98% of the product of the Last Reported Sale Price of the Common Stock and the
Conversion Rate.

         "TRUST INDENTURE ACT" means the Trust Indenture Act of 1939, as
amended, as it was in force at the date of this Indenture, except as provided in
Sections 11.03 and 15.06; provided that if the Trust Indenture Act of 1939 is
amended after the date hereof, the term "TRUST INDENTURE

                                       12

<PAGE>

ACT" shall mean, to the extent required by such amendment, the Trust Indenture
Act of 1939 as so amended.

         "TRUSTEE" means Wells Fargo Bank, N.A., a National banking association,
and its successors and any corporation resulting from or surviving any
consolidation or merger to which it or its successors may be a party and any
successor trustee at the time serving as successor trustee hereunder.

                                   ARTICLE 2
     ISSUE, DESCRIPTION, EXECUTION, REGISTRATION AND EXCHANGE OF DEBENTURES

         Section 2.01. Designation Amount and Issue of Debentures. The
Debentures shall be designated as "4.50% CONVERTIBLE SUBORDINATED DEBENTURES DUE
2023". Debentures not to exceed the aggregate principal amount of $225,000,000
(up to $270,000,000 if the Initial Purchasers exercise their option pursuant to
the Purchase Agreement dated October 9, 2003 between the Company and the Initial
Purchasers) (except pursuant to Sections 2.05, 2.06, 3.05, 3.06 and 15.02
hereof) upon the execution of this Indenture, or from time to time thereafter,
may be executed by the Company and delivered to the Trustee for authentication,
and the Trustee shall thereupon authenticate and deliver said Debentures to or
upon the written order of the Company, signed by its Chairman of the Board, its
Chief Executive Officer, its Chief Operating Officer, its President, its Chief
Financial Officer, any Vice President (whether or not designated by a number or
numbers or word or words added before or after the title "Vice President"), its
Treasurer, its Secretary or any Assistant Secretary.

         Section 2.02. Form of Debentures. The Debentures and the Trustee's
certificate of authentication to be borne by such Debentures shall be
substantially in the form set forth in Exhibit A. The terms and provisions
contained in the form of Debenture attached as Exhibit A hereto shall
constitute, and are hereby expressly made, a part of this Indenture and, to the
extent applicable, the Company and the Trustee, by their execution and delivery
of this Indenture, expressly agree to such terms and provisions and to be bound
thereby.

         Any of the Debentures may have such letters, numbers of other marks of
identification and such notations, legends, endorsements or changes as the
officers executing the same may approve (execution thereof to be conclusive
evidence of such approval) and as are not inconsistent with the provisions of
this Indenture, or as may be required by the Custodian, the Depositary or by
National Association of Securities Dealers, Inc. in order for the Debentures to
be tradable on the PORTAL Market or as may be required for the Debentures to be
tradable on any other market developed for trading of securities pursuant to
Rule 144A or as may be required to comply with any applicable law or with any
rule or regulation made pursuant thereto or with any rule or regulation of any
securities exchange or automated quotation system on which the Debentures may be
listed, or to conform to usage, or to indicate any special limitations or
restrictions to which any particular Debentures are subject.

         So long as the Debentures are eligible for book-entry settlement with
the Depositary, or unless otherwise required by law, or otherwise contemplated
by Section 2.05(a), all of the Debentures will be represented by one or more
Debentures in global form registered in the name of the Depositary or the
nominee of the Depositary (a "GLOBAL DEBENTURE"). The transfer and

                                       13

<PAGE>

exchange of beneficial interests in any such Global Debenture shall be effected
through the Depositary in accordance with this Indenture and the applicable
procedures of the Depositary. Except as provided in Section 2.05(a), beneficial
holders of a Global Debenture shall not be entitled to have certificates
registered in their names, will not receive or be entitled to receive physical
delivery of certificates in definitive form and will not be considered holders
of such Global Debenture.

         Any Global Debenture shall represent such of the outstanding Debentures
as shall be specified therein and shall provide that it shall represent the
aggregate amount of outstanding Debentures from time to time endorsed thereon
and that the aggregate amount of outstanding Debentures represented thereby may
from time to time be increased or reduced to reflect redemptions, repurchases,
conversions, transfers or exchanges permitted hereby. Any endorsement of a
Global Debenture to reflect the amount of any increase or decrease in the amount
of outstanding Debentures represented thereby shall be made by the Trustee or
the Custodian, at the direction of the Trustee, in such manner and upon
instructions given by the holder of such Debentures in accordance with this
Indenture. Payment of principal of and interest on any Global Debenture shall be
made to the holder of such Debenture.

         Section 2.03. Date and Denomination of Debentures; Payments of
Interest. The Debentures shall be issuable in registered form without coupons in
denominations of $1,000 principal amount and integral multiples thereof. Each
Debenture shall be dated the date of its authentication and shall bear interest
from the date specified on the face of the form of Debenture attached as Exhibit
A hereto. Interest on the Debentures shall be computed on the basis of a 360-day
year comprised of twelve 30-day months.

         The Person in whose name any Debenture (or its Predecessor Debenture)
is registered on the Debenture Register at the close of business on the Regular
Record Date with respect to an Interest Payment Date shall be entitled to
receive the interest payable on such Interest Payment Date, except that the
interest payable upon redemption or repurchase will be payable to the Person to
whom principal is payable pursuant to such redemption or repurchase (unless the
Redemption Date or the Repurchase Date, as the case may be, is an Interest
Payment Date, in which case the semiannual payment of interest becoming due on
such date shall be payable to the holders of such Debentures registered as such
on the applicable Regular Record Date). Notwithstanding the foregoing, if any
Debenture (or portion thereof) is converted into Common Stock during the period
after a Regular Record Date to, but excluding, the next succeeding Interest
Payment Date and such Debenture (or portion thereof) has been called or tendered
for redemption on a Redemption Date which occurs during such period, the Company
shall not be required to pay interest on such Interest Payment Date in respect
of any such Debenture (or portion thereof), except as provided in Section 15.02.
Interest shall be payable at the office of the Company maintained by the Company
for such purposes in the Borough of Manhattan, City of New York, which shall
initially be an office or agency of the Trustee. The Company shall pay interest
(i) on any Debentures in certificated form by check mailed to the address of the
Person entitled thereto as it appears in the Debenture Register (or upon written
notice, by wire transfer in immediately available funds, if such Person is
entitled to interest on Debentures with an aggregate principal amount in excess
of $2,000,000) or (ii) on any Global Debenture by wire transfer of immediately
available funds to the account of the Depositary or its nominee.

                                       14

<PAGE>

         Any interest on any Debenture which is payable, but is not punctually
paid or duly provided for, on any October 1 or April 1 (herein called "DEFAULTED
INTEREST") shall forthwith cease to be payable to the Debentureholder on the
relevant Regular Record Date by virtue of his having been such Debentureholder,
and such Defaulted Interest shall be paid by the Company, at its election in
each case, as provided in clause (1) or (2) below:

                  (1)      The Company may elect to make payment of any
         Defaulted Interest to the Persons in whose names the Debentures (or
         their respective Predecessor Debentures) are registered at the close of
         business on a "SPECIAL RECORD DATE" for the payment of such Defaulted
         Interest, which shall be the date fixed in the following manner. The
         Company shall notify the Trustee in writing of the amount of Defaulted
         Interest proposed to be paid on each Debenture and the date of the
         proposed payment (which shall be not less than twenty-five (25) days
         after the receipt by the Trustee of such notice, unless the Trustee
         shall consent to an earlier date), and at the same time the Company
         shall deposit with the Trustee an amount of money equal to the
         aggregate amount to be paid in respect of such Defaulted Interest or
         shall make arrangements satisfactory to the Trustee for such deposit on
         or prior to the date of the proposed payment, such money when deposited
         on or prior to the date of the proposed payment to be held in trust for
         the benefit of the Persons entitled to such Defaulted Interest as in
         this clause provided. Thereupon the Trustee shall fix a Special Record
         Date for the payment of such Defaulted Interest which shall be not more
         than fifteen (15) days and not less than ten (10) days prior to the
         date of the proposed payment, and not less than ten (10) days after the
         receipt by the Trustee of the notice of the proposed payment. The
         Trustee shall promptly notify the Company of such Special Record Date
         and, in the name and at the expense of the Company, shall cause notice
         of the proposed payment of such Defaulted Interest and the Special
         Record Date therefor to be mailed, first-class postage prepaid, to each
         holder at his address as it appears in the Debenture Register, not less
         than ten (10) days prior to such Special Record Date. Notice of the
         proposed payment of such Defaulted Interest and the Special Record Date
         therefor having been so mailed, such Defaulted Interest shall be paid
         to the Persons in whose names the Debentures (or their respective
         Predecessor Debentures) are registered at the close of business on such
         Special Record Date and shall no longer be payable pursuant to the
         following clause (2) of this Section 2.03.

                  (2)      The Company may make payment of any Defaulted
         Interest in any other lawful manner not inconsistent with the
         requirements of any securities exchange or automated quotation system
         on which the Debentures may be listed or designated for issuance, and
         upon such notice as may be required by such exchange or automated
         quotation system, if, after notice given by the Company to the Trustee
         of the proposed payment pursuant to this clause, such manner of payment
         shall be deemed practicable by the Trustee.

         Section 2.04. Execution of Debentures. The Debentures shall be signed
in the name and on behalf of the Company by the manual or facsimile signature of
its President, any Vice President (whether or not designated by a number or
numbers or word or words added before or after the title "Vice President"), its
Treasurer, its Secretary or any Assistant Secretary. Only such Debentures as
shall bear thereon a certificate of authentication substantially in the form set
forth on the form of Debenture attached as Exhibit A hereto, manually executed
by the Trustee (or an

                                       15

<PAGE>

authenticating agent appointed by the Trustee as provided by Section 16.13),
shall be entitled to the benefits of this Indenture or be valid or obligatory
for any purpose. Such certificate by the Trustee (or such an authenticating
agent) upon any Debenture executed by the Company shall be conclusive evidence
that the Debenture so authenticated has been duly authenticated and delivered
hereunder and that the holder is entitled to the benefits of this Indenture.

         In case any officer of the Company who shall have signed any of the
Debentures shall cease to be such officer before the Debentures so signed shall
have been authenticated and delivered by the Trustee, or disposed of by the
Company, such Debentures nevertheless may be authenticated and delivered or
disposed of as though the person who signed such Debentures had not ceased to be
such officer of the Company, and any Debenture may be signed on behalf of the
Company by such persons as, at the actual date of the execution of such
Debenture, shall be the proper officers of the Company, although at the date of
the execution of this Indenture any such person was not such an officer.

         Section 2.05. Exchange and Registration of Transfer of Debentures;
Restrictions on Transfer. (a) The Company shall cause to be kept at the
Corporate Trust Office a register (the register maintained in such office and in
any other office or agency of the Company designated pursuant to Section 5.02
being herein sometimes collectively referred to as the "DEBENTURE REGISTER") in
which, subject to such reasonable regulations as it may prescribe, the Company
shall provide for the registration of Debentures and for transfers of
Debentures. The Debenture Register shall be in written form or in any form
capable of being converted into written form within a reasonably prompt period
of time. The Trustee is hereby appointed "DEBENTURE REGISTRAR" for the purpose
of registering Debentures and transfers of Debentures as herein provided. The
Company may appoint one or more co-registrars in accordance with Section 5.02.

         Upon surrender for registration of transfer of any Debenture to the
Debenture Registrar or any co-registrar, and satisfaction of the requirements
for such transfer set forth in this Section 2.05, the Company shall execute, and
the Trustee shall authenticate and deliver, in the name of the designated
transferee or transferees, one or more new Debentures of any authorized
denominations and of a like aggregate principal amount and bearing such
restrictive legends as may be required by this Indenture.

         Debentures may be exchanged for other Debentures of any authorized
denominations and of a like aggregate principal amount, upon surrender of the
Debentures to be exchanged at any such office or agency maintained by the
Company pursuant to Section 5.02. Whenever any Debentures are so surrendered for
exchange, the Company shall execute, and the Trustee shall authenticate and
deliver, the Debentures which the Debentureholder making the exchange is
entitled to receive bearing registration numbers not contemporaneously
outstanding.

         All Debentures issued upon any registration of transfer or exchange of
Debentures shall be the valid obligations of the Company, evidencing the same
debt, and entitled to the same benefits under this Indenture, as the Debentures
surrendered upon such registration of transfer or exchange.

         All Debentures presented or surrendered for registration of transfer or
for exchange, redemption, repurchase or conversion shall (if so required by the
Company or the Debenture

                                       16

<PAGE>

Registrar) be duly endorsed, or be accompanied by a written instrument or
instruments of transfer in form satisfactory to the Company, duly executed by
the Debentureholder thereof or his attorney duly authorized in writing.

         No service charge shall be made to any holder for any registration of,
transfer or exchange of Debentures, but the Company may require payment by the
holder of a sum sufficient to cover any tax, assessment or other governmental
charge that may be imposed in connection with any registration of transfer or
exchange of Debentures.

         Neither the Company nor the Trustee nor any Debenture Registrar shall
be required to exchange or register a transfer of (a) any Debentures for a
period of fifteen (15) days next preceding any selection of Debentures to be
redeemed, (b) any Debentures or portions thereof called for redemption pursuant
to Section 3.01, (c) any Debentures or portions thereof surrendered for
conversion pursuant to Article 15, (d) any Debentures or portions thereof
tendered for repurchase (and not withdrawn) pursuant to Section 3.05 or (e) any
Debentures or portions thereof tendered for repurchase (and not withdrawn)
pursuant to Section 3.06.

         (b)      The following provisions shall apply only to Global
Debentures:

                  (i)      Each Global Debenture authenticated under this
         Indenture shall be registered in the name of the Depositary or a
         nominee thereof and delivered to such Depositary or a nominee thereof
         or Custodian therefor, and each such Global Debenture shall constitute
         a single Debenture for all purposes of this Indenture.

                  (ii)     Notwithstanding any other provision in this
         Indenture, no Global Debenture may be exchanged in whole or in part for
         Debentures registered, and no transfer of a Global Debenture in whole
         or in part may be registered, in the name of any Person other than the
         Depositary or a nominee thereof unless (A) the Depositary (I) has
         notified the Company that it is unwilling or unable to continue as
         Depositary for such Global Debenture and a successor depositary has not
         been appointed by the Company within ninety (90) days or (II) has
         ceased to be a clearing agency registered under the Exchange Act, (B)
         an Event of Default has occurred and is continuing or (C) the Company,
         in its sole discretion, notifies the Trustee in writing that it no
         longer wishes to have all the Debentures represented by Global
         Debentures. Any Global Debenture exchanged pursuant to clause (A) or
         (B) above shall be so exchanged in whole and not in part and any Global
         Debenture exchanged pursuant to clause (C) above may be exchanged in
         whole or from time to time in part as directed by the Company. Any
         Debenture issued in exchange for a Global Debenture or any portion
         thereof shall be a Global Debenture; provided that any such Debenture
         so issued that is registered in the name of a Person other than the
         Depositary or a nominee thereof shall not be a Global Debenture.

                  (iii)    Securities issued in exchange for a Global Debenture
         or any portion thereof pursuant to clause (ii) above shall be issued in
         definitive, fully registered form, without interest coupons, shall have
         an aggregate principal amount equal to that of such Global Debenture or
         portion thereof to be so exchanged, shall be registered in such names
         and be in such authorized denominations as the Depositary shall
         designate and

                                       17

<PAGE>

         shall bear any legends required hereunder. Any Global Debentures to be
         exchanged in whole shall be surrendered by the Depositary to the
         Trustee, as Debenture Registrar. With regard to any Global Debenture to
         be exchanged in part, either such Global Debenture shall be so
         surrendered for exchange or, if the Trustee is acting as Custodian for
         the Depositary or its nominee with respect to such Global Debenture,
         the principal amount thereof shall be reduced, by an amount equal to
         the portion thereof to be so exchanged, by means of an appropriate
         adjustment made on the records of the Trustee. Upon any such surrender
         or adjustment, the Trustee shall authenticate and make available for
         delivery the Debenture issuable on such exchange to or upon the written
         order of the Depositary or an authorized representative thereof.

                  (iv)     In the event of the occurrence of any of the events
         specified in clause (ii) above, the Company will promptly make
         available to the Trustee a reasonable supply of certificated Debentures
         in definitive, fully registered form, without interest coupons.

                  (v)      Neither any members of, or participants in, the
         Depositary ("AGENT MEMBERS") nor any other Persons on whose behalf
         Agent Members may act shall have any rights under this Indenture with
         respect to any Global Debenture registered in the name of the
         Depositary or any nominee thereof, and the Depositary or such nominee,
         as the case may be, 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 Debenture for all purposes whatsoever. Notwithstanding the
         foregoing, nothing herein shall prevent the Company, the Trustee or any
         agent of the Company or the Trustee from giving effect to any written
         certification, proxy or other authorization furnished by the Depositary
         or such nominee, as the case may be, or impair, as between the
         Depositary, its Agent Members and any other Person on whose behalf an
         Agent Member may act, the operation of customary practices of such
         Persons governing the exercise of the rights of a beneficial holder of
         any Debenture.

                  (vi)     At such time as all interests in a Global Debenture
         have been redeemed, repurchased, converted, canceled or exchanged for
         Debentures in certificated form, such Global Debenture shall, upon
         receipt thereof, be canceled by the Trustee in accordance with standing
         procedures and instructions existing between the Depositary and the
         Custodian. At any time prior to such cancellation, if any interest in a
         Global Debenture is redeemed, repurchased, converted, canceled or
         exchanged for Debentures in certificated form, the principal amount of
         such Global Debenture shall, in accordance with the standing procedures
         and instructions existing between the Depositary and the Custodian, be
         appropriately reduced, and an endorsement shall be made on such Global
         Debenture, by the Trustee or the Custodian, at the direction of the
         Trustee, to reflect such reduction.

         (c)      Every Debenture that bears or is required under this Section
2.05(c) to bear the legend set forth in this Section 2.05(c) (together with any
Common Stock issued upon conversion of the Debentures and required to bear the
legend set forth in Section 2.05(d), collectively, the "RESTRICTED SECURITIES")
shall be subject to the restrictions on transfer set forth in this Section
2.05(c) (including those set forth in the legend below) unless such restrictions
on transfer shall be waived by written consent of the Company, and the holder of
each such Restricted Security, by such holder's acceptance thereof, agrees to be
bound by all such

                                       18

<PAGE>

restrictions on transfer. As used in Section 2.05(c) and 2.05(d), the term
"TRANSFER" encompasses any sale, pledge, loan, transfer or other disposition
whatsoever of any Restricted Security or any interest therein.

         Until the expiration of the holding period applicable to sales thereof
under Rule 144(k) under the Securities Act (or any successor provision), any
certificate evidencing such Debenture (and all securities issued in exchange
therefor or substitution thereof, other than Common Stock, if any, issued upon
conversion thereof, which shall bear the legend set forth in Section 2.05(d), if
applicable) shall bear a legend in substantially the following form, unless such
Debenture has been sold pursuant to a registration statement that has been
declared effective under the Securities Act (and which continues to be effective
at the time of such transfer) or pursuant to Rule 144 under the Securities Act
or any similar provision then in force, or unless otherwise agreed by the
Company in writing, with written notice thereof to the Trustee:

         THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933,
         AS AMENDED (THE "SECURITIES ACT"), OR THE SECURITIES LAWS OF ANY STATE
         OR OTHER JURISDICTION. NEITHER THIS SECURITY NOR ANY INTEREST OR
         PARTICIPATION HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED,
         PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH
         REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT
         TO, SUCH REGISTRATION. THE HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE
         HEREOF, (1) REPRESENTS THAT IT IS A "QUALIFIED INSTITUTIONAL BUYER" (AS
         DEFINED IN RULE 144A UNDER THE SECURITIES ACT ("RULE 144A")); (2)
         AGREES ON ITS OWN BEHALF AND ON BEHALF OF ANY INVESTOR ACCOUNT FOR
         WHICH IT HAS PURCHASED SECURITIES, TO OFFER, SELL OR OTHERWISE TRANSFER
         SUCH SECURITY OR ANY COMMON STOCK ISSUABLE UPON CONVERSION OF SUCH
         SECURITY, PRIOR TO THE EXPIRATION OF THE HOLDING PERIOD APPLICABLE TO
         SALES OF THIS SECURITY UNDER RULE 144 UNDER THE SECURITIES ACT (OR ANY
         SUCCESSOR PROVISION) ONLY (A) TO THE ISSUER, (B) PURSUANT TO A
         REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER THE
         SECURITIES ACT (AND WHICH CONTINUES TO BE EFFECTIVE AT THE TIME OF SUCH
         TRANSFER), (C) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE
         PURSUANT TO RULE 144A, IN COMPLIANCE WITH RULE 144A TO A PERSON IT
         REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER THAT PURCHASES
         FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL
         BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN
         RELIANCE ON RULE 144A OR (D) PURSUANT TO ANOTHER AVAILABLE EXEMPTION
         FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT; SUBJECT TO
         THE ISSUER'S AND THE TRUSTEE'S RIGHT PRIOR TO ANY SUCH OFFER, SALE OR
         TRANSFER PURSUANT TO CLAUSE (D) TO REQUIRE THE DELIVERY OF AN OPINION
         OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH
         OF THEM; AND (3) AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM
         THIS SECURITY IS TRANSFERRED A NOTICE SUBSTANTIALLY TO THE EFFECT OF
         THIS LEGEND. THIS LEGEND

                                       19

<PAGE>

         WILL BE REMOVED UPON THE TRANSFER OF THIS SECURITY PURSUANT TO CLAUSE
         2(B) ABOVE OR UNDER RULE 144 UNDER THE SECURITIES ACT (OR ANY SUCCESSOR
         PROVISION).

         THE HOLDER OF THIS SECURITY IS ENTITLED TO THE BENEFITS OF A
         REGISTRATION RIGHTS AGREEMENT DATED AS OF OCTOBER 17, 2003 AND, BY ITS
         ACCEPTANCE HEREOF, AGREES TO BE BOUND BY AND TO COMPLY WITH THE
         PROVISIONS OF SUCH REGISTRATION RIGHTS AGREEMENT.

         Any Debenture (or security issued in exchange or substitution therefor)
as to which such restrictions on transfer shall have expired in accordance with
their terms or as to which the conditions for removal of the foregoing legend
set forth therein have been satisfied may, upon surrender of such Debenture for
exchange to the Debenture Registrar in accordance with the provisions of this
Section 2.05, be exchanged for a new Debenture or Debentures, of like tenor and
aggregate principal amount, which shall not bear the restrictive legend required
by this Section 2.05(c). If the Restricted Security surrendered for exchange is
represented by a Global Debenture bearing the legend set forth in this Section
2.05(c), the principal amount of the legended Global Debenture shall be reduced
by the appropriate principal amount and the principal amount of a Global
Debenture without the legend set forth in this Section 2.05(c) shall be
increased by an equal principal amount. If a Global Debenture without the legend
set forth in this Section 2.05(c) is not then outstanding, the Company shall
execute and the Trustee shall authenticate and deliver an unlegended Global
Debenture to the Depositary.

         (d)      Until the expiration of the holding period applicable to sales
thereof under Rule 144(k) under the Securities Act (or any successor provision),
any stock certificate representing Common Stock issued upon conversion of any
Debenture shall bear a legend in substantially the following form, unless such
Common Stock has been sold pursuant to a registration statement that has been
declared effective under the Securities Act (and which continues to be effective
at the time of such transfer) or pursuant to Rule 144 under the Securities Act
or any similar provision then in force, or such Common Stock has been issued
upon conversion of Debentures that have been transferred pursuant to a
registration statement that has been declared effective under the Securities Act
or pursuant to Rule 144 under the Securities Act or any similar provision then
in force, or unless otherwise agreed by the Company in writing with written
notice thereof to the transfer agent:

         THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933,
         AS AMENDED (THE "SECURITIES ACT"), OR THE SECURITIES LAWS OF ANY STATE
         OR OTHER JURISDICTION. NEITHER THIS SECURITY NOR ANY INTEREST OR
         PARTICIPATION HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED,
         PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH
         REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT
         TO, SUCH REGISTRATION. THE HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE
         HEREOF, (1) REPRESENTS THAT IT IS A "QUALIFIED INSTITUTIONAL BUYER" (AS
         DEFINED IN RULE 144A UNDER THE SECURITIES ACT ("RULE 144A")); (2)
         AGREES ON ITS OWN BEHALF AND ON BEHALF OF ANY INVESTOR ACCOUNT FOR
         WHICH IT HAS PURCHASED SECURITIES, TO

                                       20

<PAGE>

         OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE
         EXPIRATION OF THE HOLDING PERIOD APPLICABLE TO SALES OF THIS SECURITY
         UNDER RULE 144 UNDER THE SECURITIES ACT (OR ANY SUCCESSOR PROVISION)
         ONLY (A) TO THE ISSUER, (B) PURSUANT TO A REGISTRATION STATEMENT THAT
         HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT (AND WHICH
         CONTINUES TO BE EFFECTIVE AT THE TIME OF SUCH TRANSFER), (C) FOR SO
         LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A,
         IN COMPLIANCE WITH RULE 144A TO A PERSON IT REASONABLY BELIEVES IS A
         QUALIFIED INSTITUTIONAL BUYER THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR
         THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN
         THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A OR (D)
         PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE REGISTRATION
         REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE ISSUER'S AND THE
         TRUSTEE'S RIGHT PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO
         CLAUSE (D) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL,
         CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM;
         AND (3) AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THIS
         SECURITY IS TRANSFERRED A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS
         LEGEND. THIS LEGEND WILL BE REMOVED UPON THE EARLIER OF THE TRANSFER OF
         THIS SECURITY PURSUANT TO CLAUSE 2(B) ABOVE OR UPON ANY TRANSFER OF
         THIS SECURITY UNDER RULE 144 UNDER THE SECURITIES ACT (OR ANY SUCCESSOR
         PROVISION).

         THE HOLDER OF THIS SECURITY IS ENTITLED TO THE BENEFITS OF A
         REGISTRATION RIGHTS AGREEMENT DATED AS OF OCTOBER 17, 2003 AND, BY ITS
         ACCEPTANCE HEREOF, AGREES TO BE BOUND BY AND TO COMPLY WITH THE
         PROVISIONS OF SUCH REGISTRATION RIGHTS AGREEMENT.

         Any such Common Stock as to which such restrictions on transfer shall
have expired in accordance with their terms or as to which the conditions for
removal of the foregoing legend set forth therein have been satisfied may, upon
surrender of the certificates representing such shares of Common Stock for
exchange in accordance with the procedures of the transfer agent for the Common
Stock, be exchanged for a new certificate or certificates for a like number of
shares of Common Stock, which shall not bear the restrictive legend required by
this Section 2.05(d).

         (e)      Any Debenture or Common Stock issued upon the conversion of a
Debenture that, prior to the expiration of the holding period applicable to
sales thereof under Rule 144(k) under the Securities Act (or any successor
provision), is purchased or owned by the Company or any Affiliate thereof may
not be resold by the Company or such Affiliate unless registered under the
Securities Act or resold pursuant to an exemption from the registration
requirements of the Securities Act in a transaction which results in such
Debentures or Common Stock, as the case may be, no longer being "RESTRICTED
SECURITIES" (as defined under Rule 144).

         The Trustee shall have no obligation or duty to monitor, determine or
inquire as to compliance with any restrictions on transfer imposed under this
Indenture or under applicable

                                       21

<PAGE>

law with respect to any transfer of any interest in any Debenture (including any
transfers between or among Agent Members or beneficial holders of interests in
any Global Debenture) other than to require delivery of such certificates and
other documentation or evidence as are expressly required by, and to do so if
and when expressly required by, the terms of this Indenture, and to examine the
same to determine substantial compliance as to form with the express
requirements hereof.

         Section 2.06. Mutilated, Destroyed, Lost or Stolen Debentures. In case
any Debenture shall become mutilated or be destroyed, lost or stolen, the
Company in its discretion may execute, and upon its written request the Trustee
or an authenticating agent appointed by the Trustee shall authenticate and make
available for delivery, a new Debenture, bearing a number not contemporaneously
outstanding, in exchange and substitution for the mutilated Debenture, or in
lieu of and in substitution for the Debenture so destroyed, lost or stolen. In
every case, the applicant for a substituted Debenture shall furnish to the
Company, to the Trustee and, if applicable, to such authenticating agent such
security or indemnity as may be required by them to save each of them harmless
for any loss, liability, cost or expense caused by or connected with such
substitution, and, in every case of destruction, loss or theft, the applicant
shall also furnish to the Company, to the Trustee and, if applicable, to such
authenticating agent evidence to their satisfaction of the destruction, loss or
theft of such Debenture and of the ownership thereof.

         Following receipt by the Trustee or such authenticating agent, as the
case may be, of satisfactory security or indemnity and evidence as described in
the preceding paragraph, the Trustee or such authenticating agent may
authenticate any such substituted Debenture and make available for delivery such
Debenture. Upon the issuance of any substituted Debenture, the Company may
require the payment by the holder of a sum sufficient to cover any tax,
assessment or other governmental charge that may be imposed in relation thereto
and any other expenses connected therewith. In case any Debenture which has
matured or is about to mature or has been called for redemption or has been
tendered for repurchase upon a Repurchase Date (and not withdrawn) or is to be
converted into Common Stock shall become mutilated or be destroyed, lost or
stolen, the Company may, instead of issuing a substitute Debenture, pay or
authorize the payment of or convert or authorize the conversion of the same
(without surrender thereof except in the case of a mutilated Debenture), as the
case may be, if the applicant for such payment or conversion shall furnish to
the Company, to the Trustee and, if applicable, to such authenticating agent
such security or indemnity as may be required by them to save each of them
harmless from any loss, liability, cost or expense caused by or in connection
with such substitution, and, in every case of destruction, loss or theft, the
applicant shall also furnish to the Company, the Trustee and, if applicable, any
Paying Agent or Conversion Agent evidence to their satisfaction of the
destruction, loss or theft of such Debenture and of the ownership thereof.

         Every substitute Debenture issued pursuant to the provisions of this
Section 2.06 by virtue of the fact that any Debenture is destroyed, lost or
stolen shall constitute an additional contractual obligation of the Company,
whether or not the destroyed, lost or stolen Debenture shall be found at any
time, and shall be entitled to all the benefits of (but shall be subject to all
the limitations set forth in) this Indenture equally and proportionately with
any and all other Debentures duly issued hereunder. To the extent permitted by
law, all Debentures shall be held and owned upon the express condition that the
foregoing provisions are exclusive with respect to the replacement or payment or
conversion or redemption or repurchase of mutilated, destroyed,

                                       22

<PAGE>

lost or stolen Debentures and shall preclude any and all other rights or
remedies notwithstanding any law or statute existing or hereafter enacted to the
contrary with respect to the replacement or payment or conversion or redemption
or repurchase of negotiable instruments or other securities without their
surrender.

         Section 2.07. Temporary Debentures. Pending the preparation of
Debentures in certificated form, the Company may execute and the Trustee or any
authenticating agent appointed by the Trustee shall, upon the written request of
the Company, authenticate and deliver temporary Debentures (printed or
lithographed). Temporary Debentures shall be issuable in any authorized
denomination, and substantially in the form of the Debentures in certificated
form, but with such omissions, insertions and variations as may be appropriate
for temporary Debentures, all as may be determined by the Company. Every such
temporary Debenture shall be executed by the Company and authenticated by the
Trustee or such authenticating agent upon the same conditions and in
substantially the same manner, and with the same effect, as the Debentures in
certificated form. Without unreasonable delay, the Company will execute and
deliver to the Trustee or such authenticating agent Debentures in certificated
form and thereupon any or all temporary Debentures may be surrendered in
exchange therefor, at each office or agency maintained by the Company pursuant
to Section 5.02, and the Trustee or such authenticating agent shall authenticate
and make available for delivery in exchange for such temporary Debentures an
equal aggregate principal amount of Debentures in certificated form. Such
exchange shall be made by the Company at its own expense and without any charge
therefor. Until so exchanged, the temporary Debentures shall in all respects be
entitled to the same benefits and subject to the same limitations under this
Indenture as Debentures in certificated form authenticated and delivered
hereunder.

         Section 2.08. Cancellation of Debentures. All Debentures surrendered
for the purpose of payment, redemption, repurchase, conversion, exchange or
registration of transfer shall, if surrendered to the Company or any Paying
Agent or any Debenture Registrar or any Conversion Agent, be surrendered to the
Trustee and promptly canceled by it, or, if surrendered to the Trustee, shall be
promptly canceled by it, and no Debentures shall be issued in lieu thereof
except as expressly permitted by any of the provisions of this Indenture. The
Trustee shall dispose of such canceled Debentures in accordance with its
customary procedures. If the Company shall acquire any of the Debentures, such
acquisition shall not operate as a redemption, repurchase or satisfaction of the
Indebtedness represented by such Debentures unless and until the same are
delivered to the Trustee for cancellation.

         Section 2.09. CUSIP Numbers. The Company in issuing the Debentures may
use "CUSIP" numbers (if then generally in use), and, if so, the Trustee shall
use "CUSIP" numbers in notices of redemption as a convenience to
Debentureholders; provided that any such notice may state that no representation
is made as to the correctness of such numbers either as printed on the
Debentures or as contained in any notice of a redemption and that reliance may
be placed only on the other identification numbers printed on the Debentures,
and any such redemption shall not be affected by any defect in or omission of
such numbers. The Company will promptly notify the Trustee of any change in the
"CUSIP" numbers.

                                       23

<PAGE>

                                   ARTICLE 3
                     REDEMPTION AND REPURCHASE OF DEBENTURES

         Section 3.01. Company's Right to Redeem. Prior to October 8, 2008, the
Debentures will not be redeemable at the Company's option. At any time on or
after October 8, 2008 and prior to Stated Maturity, the Company, at its option,
may redeem the Debentures in accordance with the provisions of Section 3.02,
Section 3.03 and Section 3.04 on the Redemption Date for cash, in whole or in
part, at a redemption price (the "REDEMPTION PRICE") equal to 100% of the
principal amount of the Debentures to be redeemed together in each case with
accrued and unpaid interest on the Debentures redeemed to (but excluding) the
Redemption Date.

         Section 3.02. Notice of Optional Redemption; Selection of Debentures.
(a) In case the Company shall desire to exercise the right to redeem all or, as
the case may be, any part of the Debentures pursuant to Section 3.01, it shall
fix a date for redemption (the "REDEMPTION DATE") and it or, at its written
request received by the Trustee not fewer than forty-five (45) days prior (or
such shorter period of time as may be acceptable to the Trustee) to the
Redemption Date, the Trustee in the name of and at the expense of the Company,
shall mail or cause to be mailed a notice of such redemption (a "REDEMPTION
NOTICE") not fewer than thirty (30) nor more than sixty (60) days prior to the
Redemption Date to each holder of Debentures so to be redeemed as a whole or in
part at its last address as the same appears on the Debenture Register; provided
that if the Company shall give such notice, it shall also give written notice of
the Redemption Date to the Trustee. Such mailing shall be by first class mail.
The notice, if mailed in the manner herein provided, shall be conclusively
presumed to have been duly given, whether or not the holder receives such
notice. In any case, failure to give such notice by mail or any defect in the
notice to the holder of any Debenture designated for redemption as a whole or in
part shall not affect the validity of the proceedings for the redemption of any
other Debenture. Concurrently with the mailing of any such Redemption Notice,
the Company shall issue a press release announcing such redemption, the form and
content of which press release shall be determined by the Company in its sole
discretion. The failure to issue any such press release or any defect therein
shall not affect the validity of the Redemption Notice or any of the proceedings
for the redemption of any Debenture called for redemption.

         (b)      Each such Redemption Notice shall specify the aggregate
principal amount of Debentures to be redeemed, the CUSIP number or numbers of
the Debentures being redeemed, the Redemption Date (which shall be a Business
Day), the Redemption Price at which Debentures are to be redeemed, the place or
places of payment, that payment will be made upon presentation and surrender of
such Debentures, that interest accrued to the Redemption Date will be paid as
specified in said notice, and that on and after said date interest thereon or on
the portion thereof to be redeemed will cease to accrue. Such notice shall also
state the current Conversion Rate, the date on which the right to convert such
Debentures or portions thereof into Common Stock will expire (which date shall
not be later than the close of business on the second Business Day prior to the
Redemption Date), whether the Company has elected to satisfy all or a portion of
its Conversion Obligation with cash in lieu of delivery of shares of Common
Stock with respect to any Debentures converted prior to the Redemption Date and,
if the Company has determined to satisfy all or any portion of the Conversion
Obligation in cash, the dollar amount of the conversion to be satisfied in cash
(which must be expressed either as 100% of the Conversion Obligation or as a
fixed dollar amount). If fewer than all the Debentures are to be

                                       24

<PAGE>

redeemed, the Redemption Notice shall identify the Debentures to be redeemed
(including CUSIP numbers, if any). In case any Debenture is to be redeemed in
part only, the Redemption Notice shall state the portion of the principal amount
thereof to be redeemed and shall state that, on and after the Redemption Date,
upon surrender of such Debenture, a new Debenture or Debentures in principal
amount equal to the unredeemed portion thereof will be issued.

         (c)      On or prior to the Redemption Date specified in the Redemption
Notice given as provided in this Section 3.02, the Company will deposit with the
Trustee or with one or more Paying Agents (or, if the Company is acting as its
own Paying Agent, set aside, segregate and hold in trust as provided in Section
5.04) an amount of money in immediately available funds sufficient to redeem on
the Redemption Date all the Debentures (or portions thereof) so called for
redemption (other than those theretofore surrendered for conversion into Common
Stock) at the appropriate Redemption Price; provided that if such payment is
made on the Redemption Date, it must be received by the Trustee or Paying Agent,
as the case may be, by 10:00 a.m., New York City time, on such date. The Company
shall be entitled to retain any interest, yield or gain on amounts deposited
with the Trustee or any Paying Agent pursuant to this Section 3.02(c) in excess
of amounts required hereunder to pay the Redemption Price and accrued interest
to, but excluding, the Redemption Date. Subject to the last sentence of Section
8.05, if any Debenture called for redemption is converted pursuant hereto prior
to such Redemption Date, any money deposited with the Trustee or any Paying
Agent or so segregated and held in trust for the redemption of such Debenture
shall be paid to the Company upon its written request, or, if then held by the
Company, shall be discharged from such trust. Whenever any Debentures are to be
redeemed, the Company will give the Trustee written notice in the form of an
Officers' Certificate not fewer than thirty-five (35) days (or such shorter
period of time as may be acceptable to the Trustee) prior to the Redemption Date
as to the aggregate principal amount of Debentures to be redeemed.

         (d)      If less than all of the outstanding Debentures are to be
redeemed, the Trustee shall select the Debentures or portions thereof of the
Global Debenture or the Debentures in certificated form to be redeemed (in
principal amounts of $1,000 or multiples thereof) by lot, on a pro rata basis or
by another method the Trustee deems fair and appropriate. If any Debenture
selected for partial redemption is submitted for conversion in part after such
selection, the portion of such Debenture submitted for conversion shall be
deemed (so far as may be possible) to be from the portion selected for
redemption. The Debentures (or portions thereof) so selected shall be deemed
duly selected for redemption for all purposes hereof, notwithstanding that any
such Debenture is submitted for conversion in part before the mailing of the
Redemption Notice.

         Upon any redemption of less than all of the outstanding Debentures, the
Company and the Trustee may (but need not), solely for purposes of determining
the pro rata allocation among such Debentures as are unconverted and outstanding
at the time of redemption, treat as outstanding any Debentures surrendered for
conversion during the period of fifteen (15) days next preceding the mailing of
a Redemption Notice and may (but need not) treat as outstanding any Debenture
authenticated and delivered during such period in exchange for the unconverted
portion of any Debenture converted in part during such period.

         Section 3.03. Payment of Debentures Called for Redemption by the
Company. If notice of redemption has been given as provided in Section 3.02, the
Debentures or portion of

                                       25

<PAGE>

Debentures with respect to which such notice has been given shall, unless
converted into Common Stock pursuant to the terms hereof, become due and payable
on the Redemption Date and at the place or places stated in such notice at the
applicable Redemption Price, and on and after the Redemption Date (unless the
Company shall default in the payment of such Debentures at the Redemption Price)
interest on the Debentures or portion of Debentures so called for redemption
shall cease to accrue and, after the close of business on the second Business
Day immediately preceding the Redemption Date (unless the Company shall default
in the payment of such Debentures at the Redemption Price), such Debentures
shall cease to be convertible into Common Stock and, except as provided in
Section 8.05, to be entitled to any benefit or security under this Indenture,
and the holders thereof shall have no right in respect of such Debentures except
the right to receive the Redemption Price thereof. On presentation and surrender
of such Debentures at a place of payment in said notice specified, the said
Debentures or the specified portions thereof shall be paid and redeemed by the
Company at the applicable Redemption Price; provided that if the applicable
Redemption Date is an Interest Payment Date, the interest payable on such
Interest Payment Date shall be paid on such Interest Payment Date to the holders
of record of such Debentures on the applicable record date instead of the
holders surrendering such Debentures for redemption on such date.

         Upon presentation of any Debenture redeemed in part only, the Company
shall execute and the Trustee shall authenticate and make available for delivery
to the holder thereof, at the expense of the Company, a new Debenture or
Debentures, of authorized denominations, in principal amount equal to the
unredeemed portion of the Debentures so presented.

         Notwithstanding the foregoing, the Trustee shall not redeem any
Debentures or mail any Redemption Notice during the continuance of a default in
payment of interest on the Debentures. If any Debenture called for redemption
shall not be so paid upon surrender thereof for redemption, the principal shall,
until paid or duly provided for, continue to bear interest at the rate borne by
the Debenture, compounded semiannually, and such Debenture shall remain
convertible into Common Stock until the principal and interest shall have been
paid or duly provided for.

         Section 3.04. Conversion Arrangement on Call for Redemption. In
connection with any redemption of Debentures, the Company may arrange for the
purchase and conversion of any Debentures by an agreement with one or more
investment banks or other purchasers to purchase such Debentures by paying to
the Trustee in trust for the Debentureholders, on or before the Redemption Date,
an amount not less than the applicable Redemption Price of such Debentures.
Notwithstanding anything to the contrary contained in this Article 3, the
obligation of the Company to pay the Redemption Price of such Debentures shall
be deemed to be satisfied and discharged to the extent such amount is so paid by
such purchasers. If such an agreement is entered into, a copy of which will be
filed with the Trustee prior to the Redemption Date, any Debentures not duly
surrendered for conversion by the holders thereof may, at the option of the
Company, be deemed, to the fullest extent permitted by law, acquired by such
purchasers from such holders and (notwithstanding anything to the contrary
contained in Article 15) surrendered by such purchasers for conversion, all as
of immediately prior to the close of business on the Redemption Date (and the
right to convert any such Debentures shall be extended through such time),
subject to payment of the above amount as aforesaid. At the direction of the
Company, the Trustee shall hold and dispose of any such amount paid to it in the
same manner as it would

                                       26

<PAGE>

monies deposited with it by the Company for the redemption of Debentures.
Without the Trustee's prior written consent, no arrangement between the Company
and such purchasers for the purchase and conversion of any Debentures shall
increase or otherwise affect any of the powers, duties, responsibilities or
obligations of the Trustee as set forth in this Indenture.

         Section 3.05. Repurchase of Debentures by the Company at Option of
Holders upon a Fundamental Change. (a) If a Fundamental Change shall occur at
any time prior to Stated Maturity, each holder shall have the right, at such
holder's option, to require the Company to repurchase all of such holder's
Debentures, or any portion thereof that is a multiple of $1,000 principal
amount, on the date specified in the Fundamental Change Repurchase Notice, which
date shall be no more than thirty-five (35) Business Days after the occurrence
of such Fundamental Change but in no event prior to the date on which such
Fundamental Change occurs (the "FUNDAMENTAL CHANGE REPURCHASE DATE"). The
Company shall repurchase such Debentures at a price (the "FUNDAMENTAL CHANGE
REPURCHASE PRICE") equal to 100% of the principal amount thereof plus any
accrued and unpaid interest to but excluding the Fundamental Change Repurchase
Date; provided that if such Fundamental Change Repurchase Date falls on an
Interest Payment Date, then the interest payable on such Interest Payment Date
shall be paid to the holders of record of the Debentures on the applicable
record date instead of the holders surrendering the Debentures for repurchase on
such date.

         The Company's obligation to repurchase all or a portion of a holder's
Debentures under this Section 3.05 shall be satisfied if a third party makes the
offer to repurchase the Debentures at the Fundamental Change Repurchase Price in
the manner and at the times and otherwise in compliance in all material respects
with the requirements set out in this Section 3.05 and such third party complies
with the obligations of the Company in connection herewith.

         (b)      On or before the twenty-fifth (25th) Business Day prior to
each Fundamental Change Repurchase Date, the Company, or at its written request
the Trustee in the name of and at the expense of the Company (which request must
be received by the Trustee at least ten (10) Business Days prior to the date the
Trustee is requested to give notice as described below), unless the Trustee
shall agree to a shorter period), shall mail or cause to be mailed, by first
class mail, to all holders of record on such date a notice (the "FUNDAMENTAL
CHANGE REPURCHASE NOTICE") of the occurrence of such Fundamental Change and of
the repurchase right at the option of the holders arising as a result thereof to
each holder of Debentures at its last address as the same appears on the
Debenture Register; provided that if the Company shall give such notice, it
shall also give written notice of the Fundamental Change to the Trustee at such
time as it is mailed to Debentureholders. Such notice, if mailed in the manner
herein provided, shall be conclusively presumed to have been duly given, whether
or not the holder receives such notice. Each Fundamental Change Repurchase
Notice shall state:

                  (i)      the Fundamental Change Repurchase Price, excluding
         accrued and unpaid interest, the applicable Conversion Rate at the time
         of such notice (and any applicable adjustments to the Conversion Rate)
         and, to the extent known at the time of such notice, the amount of
         interest that will be payable with respect to the Debentures on the
         Fundamental Change Repurchase Date;

                                       27

<PAGE>

                  (ii)     whether the Company elects to pay the Fundamental
         Change Repurchase Price in cash, in shares of Common Stock or a
         combination thereof, specifying the percentage or amount of each;

                  (iii)    if the Company elects to pay any portion of the
         Fundamental Change Repurchase Price in shares of Common Stock, the
         method of calculating the Market Price of the Common Stock;

                  (iv)     the events causing the Fundamental Change and the
         date of the Fundamental Change;

                  (v)      the Fundamental Change Repurchase Date;

                  (vi)     the last date on which a holder may exercise the
                           repurchase right;

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

                  (viii)   that Debentures as to which a Fundamental Change
         Repurchase Election has been given by the holder may be converted only
         if the election has been withdrawn by the holder in accordance with the
         terms of this Indenture; provided that the Debentures are otherwise
         convertible in accordance with Section 15.01;

                  (ix)     that the holder shall have the right to withdraw any
         Debentures surrendered prior to the close of business on the Business
         Day immediately preceding the Fundamental Change Repurchase Date (or
         any such later time as may be required by applicable law);

                  (x)      a description of the procedure which a
         Debentureholder must follow to exercise such repurchase right or to
         withdraw any surrendered Debentures;

                  (xi)     the CUSIP number or numbers of the Debentures (if
         then generally in use); and

                  (xii)    briefly, the conversion rights of the Debentures and
         whether, at the time of such notice, the Debentures are eligible for
         conversion.

         No failure of the Company to give the foregoing notices and no defect
therein shall limit the Debentureholders' repurchase rights or affect the
validity of the proceedings for the repurchase of the Debentures pursuant to
this Section 3.05.

         (c)      Debentures shall be repurchased pursuant to this Section 3.05
at the option of the holder upon:

                  (i)      delivery to the Trustee (or other Paying Agent
         appointed by the Company) by a holder of a duly completed notice (a
         "FUNDAMENTAL CHANGE REPURCHASE ELECTION") in the form set forth on the
         reverse of the Debenture at any time prior to the close of business on
         the Business Day immediately preceding the Fundamental Change
         Repurchase Date stating:

                                       28

<PAGE>

                  (A)      if certificated, the certificate numbers of the
         Debentures which the holder shall deliver to be repurchased;

                  (B)      the portion of the principal amount of the Debentures
         that the holder shall deliver to be repurchased, which portion must be
         $1,000 or an integral multiple thereof;

                  (C)      that such Debentures shall be repurchased as of the
         Fundamental Change Repurchase Date pursuant to the terms and conditions
         specified in the Debentures and in the Indenture; and

                  (D)      in the event the Company elects to pay the
         Fundamental Change Repurchase Price, in whole or in part, in shares of
         Common Stock but such portion of the Fundamental Change Repurchase
         Price shall ultimately be paid to such holder entirely in cash because
         any of the conditions to payment of the Fundamental Change Repurchase
         Price in shares of Common Stock is not satisfied prior to the close of
         business on the Business Day prior to the relevant Fundamental Change
         Repurchase Date, whether such holder elects (i) to withdraw such
         Fundamental Change Repurchase Election as to some or all of the
         Debentures to which such election relates (stating the principal amount
         and certificate numbers, if any, of the Debentures as to which such
         withdrawal shall relate) or (ii) to receive cash in respect of the
         entire Fundamental Change Repurchase Price for all Debentures (or
         portions thereof) to which such election relates; and

                  (ii)     delivery or book-entry transfer of the Debentures to
         the Trustee (or other Paying Agent appointed by the Company)
         simultaneously with or at any time after delivery of the Fundamental
         Change Repurchase Election (together with all necessary endorsements)
         at the Corporate Trust Office of the Trustee (or other Paying Agent
         appointed by the Company) in the Borough of Manhattan, such delivery or
         transfer being a condition to receipt by the holder of the Fundamental
         Change Repurchase Price therefor; provided that such Fundamental Change
         Repurchase Price shall be so paid pursuant to this Section 3.05 only if
         the Debentures so delivered or transferred to the Trustee (or other
         Paying Agent appointed by the Company) shall conform in all respects to
         the description thereof in the related Fundamental Change Repurchase
         Election. All questions as to the validity, eligibility (including time
         of receipt) and acceptance of any Debenture for repurchase shall be
         determined by the Company, whose determination shall be final and
         binding absent manifest error.

         If a holder fails to indicate such holder's choice with respect to the
election set forth in Section 3.05(c)(i)(D), such holder shall be deemed to have
elected to receive cash in respect of the entire Fundamental Change Repurchase
Price for all Debentures subject to such Fundamental Change Repurchase Election
in the circumstances set forth in Section 3.05(c)(i)(D).

         Section 3.06. Repurchase of Debentures by the Company at Option of
Holders on Specified Dates. (a) On each of October 1, 2008, October 1, 2013 and
October 1, 2018 (each, a "COMPANY REPURCHASE DATE"), each holder shall have the
right, at such holder's option, to

                                       29

<PAGE>

require the Company to repurchase all of such holder's Debentures, or any
portion thereof that is a multiple of $1,000 principal amount. The Company shall
repurchase such Debentures at a price (the "COMPANY REPURCHASE PRICE") equal to
100% of the principal amount thereof plus any accrued and unpaid interest to but
excluding the Company Repurchase Date; provided that if such Company Repurchase
Date falls on an Interest Payment Date, then the interest payable on such
Interest Payment Date shall be paid to the holders of record of the Debentures
on the applicable record date instead of the holders surrendering the Debentures
for repurchase on such date.

         (b)      On or before the twenty-fifth (25th) Business Day prior to
each Company Repurchase Date, the Company, or at its written request the Trustee
in the name of and at the expense of the Company (which request must be received
by the Trustee at least ten (10) Business Days prior to the date the Trustee is
requested to give notice as described below), unless the Trustee shall agree to
a shorter period), shall mail or cause to be mailed, by first class mail, to all
holders of record on such date a notice (the "COMPANY REPURCHASE NOTICE") to
each holder of Debentures at its last address as the same appears on the
Debenture Register; provided that if the Company shall give such notice, it
shall also give written notice to the Trustee at such time as it is mailed to
Debentureholders. Such notice, if mailed in the manner herein provided, shall be
conclusively presumed to have been duly given, whether or not the holder
receives such notice. Each Company Repurchase Notice shall state:

                  (i)      the Company Repurchase Price, excluding accrued and
         unpaid interest, the applicable Conversion Rate at the time of such
         notice (and any applicable adjustments to the Conversion Rate) and, to
         the extent known at the time of such notice, the amount of interest
         that will be payable with respect to the Debentures on the Company
         Repurchase Date;

                  (ii)     whether the Company elects to pay the Company
         Repurchase Price in cash, in shares of Common Stock or a combination
         thereof, specifying the percentage or amounts of each;

                  (iii)    if the Company elects to pay any portion of the
         Company Repurchase Price in whole or in part in shares of Common Stock,
         the method of calculating the Market Price of the Common Stock;

                  (iv)     the Company Repurchase Date;

                  (v)      the last date on which a holder may exercise the
         repurchase right;

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

                  (vii)    that Debentures as to which a Company Repurchase
         Election has been given by the holder may be converted only if the
         election has been withdrawn by the holder in accordance with the terms
         of this Indenture; provided that the Debentures are otherwise
         convertible in accordance with Section 15.01;

                                       30

<PAGE>

                  (viii)   that the holder shall have the right to withdraw any
         Debentures surrendered prior to the close of business on the Business
         Day immediately preceding the Company Repurchase Date (or any such
         later time as may be required by applicable law);

                  (ix)     a description of the procedure which a
         Debentureholder must follow to exercise such repurchase right or to
         withdraw any surrendered Debentures;

                  (x)      the CUSIP number or numbers of the Debentures (if
         then generally in use); and

                  (xi)     briefly, the conversion rights of the Debentures and
         whether, at the time of such notice, the Debentures are eligible for
         conversion.

         No failure of the Company to give the foregoing notices and no defect
therein shall limit the Debentureholders' repurchase rights or affect the
validity of the proceedings for the repurchase of the Debentures pursuant to
this Section 3.06.

         (c)      Debentures shall be repurchased pursuant to this Section 3.06
at the option of the holder upon:

                  (i)      delivery to the Trustee (or other Paying Agent
         appointed by the Company) by a holder of a duly completed notice (a
         "COMPANY REPURCHASE ELECTION") in the form set forth on the reverse of
         the Debenture at any time from the opening of business on the twentieth
         (20th) Business Day preceding the Company Repurchase Date until the
         close of business on the Business Day immediately preceding the Company
         Repurchase Date stating:

                           (A)      if certificated, the certificate numbers of
                  the Debentures which the holder shall deliver to be
                  repurchased;

                           (B)      the portion of the principal amount of the
                  Debentures that the holder shall deliver to be repurchased,
                  which portion must be $1,000 or an integral multiple thereof;

                           (C)      that such Debentures shall be repurchased as
                  of the Company Repurchase Date pursuant to the terms and
                  conditions specified in the Debentures and in this Indenture;
                  and

                           (D)      in the event the Company elects to pay the
                  Company Repurchase Price, in whole or in part, in shares of
                  Common Stock but such portion of the Company Repurchase Price
                  shall ultimately be paid to such holder entirely in cash
                  because any of the conditions to payment of the Company
                  Repurchase Price in shares of Common Stock is not satisfied
                  prior to the close of business on the Business Day prior to
                  the relevant Company Repurchase Date, whether such holder
                  elects (i) to withdraw the Company Repurchase Election as to
                  some or all of the Debentures to which such election relates
                  (stating the principal amount and certificate numbers, if any,
                  of the Debentures as to which such withdrawal shall

                                       31

<PAGE>

                  relate), or (ii) to receive cash in respect of the entire
                  Repurchase Price for all Debentures (or portions thereof) to
                  which such election relates; and

                  (ii)     delivery or book-entry transfer of the Debentures to
         the Trustee (or other Paying Agent appointed by the Company)
         simultaneously with or at any time after delivery of the Company
         Repurchase Election (together with all necessary endorsements) at the
         Corporate Trust Office of the Trustee (or other Paying Agent appointed
         by the Company) in the Borough of Manhattan, such delivery or transfer
         being a condition to receipt by the holder of the Company Repurchase
         Price therefor; provided that such Company Repurchase Price shall be so
         paid pursuant to this Section 3.06 only if the Debentures so delivered
         or transferred to the Trustee (or other Paying Agent appointed by the
         Company) shall conform in all respects to the description thereof in
         the related Company Repurchase Election. All questions as to the
         validity, eligibility (including time of receipt) and acceptance of any
         Debenture for repurchase shall be determined by the Company, whose
         determination shall be final and binding absent manifest error.

         If a holder fails to indicate such holder's choice with respect to the
election set forth in Section 3.06(c)(i)(D), such holder shall be deemed to have
elected to receive cash in respect of the entire Company Repurchase Price for
all Debentures subject to such Company Repurchase Election in the circumstances
set forth in Section 3.06(c)(i)(D).

         Section 3.07. Company's Right to Elect Manner of Payment of Repurchase
Price. (a) The Debentures to be repurchased by the Company on any Repurchase
Date pursuant to Section 3.05 or Section 3.06 (other than the Company Repurchase
Date occurring on October 1, 2008), may be paid for, in whole or in part, at the
election of the Company, in U.S. legal tender ("CASH") or shares of Common
Stock, or in any combination of cash and shares of Common Stock, subject to the
conditions set forth in Section 3.07(e). The Repurchase Price with respect to
the Company Repurchase Date occurring on October 1, 2008 shall be paid only in
cash. The Company shall designate in its Repurchase Notice whether the Company
will purchase the Debentures for cash or shares of Common Stock, or, if a
combination thereof, the percentage of the Repurchase Price that it will pay in
cash and the percentage that it will pay in shares of Common Stock; provided
that the Company will pay cash for accrued and unpaid interest and for
fractional interests in shares of Common Stock in an amount based upon the
Market Price of such fractional shares. For purposes of determining the amount
of any fractional interests, all Debentures subject to repurchase held by a
holder shall be considered together (no matter how many separate certificates
are to be presented).

         (b)      Each holder whose Debentures are repurchased pursuant to
Section 3.05 or Section 3.06 shall receive the same percentage of cash or shares
of Common Stock in payment of the Repurchase Price for such Debentures as any
other holder whose Debentures are repurchased, except (i) as provided in Section
3.07(a) with regard to the payment of cash in lieu of fractional shares of
Common Stock and (ii) in the event that the Company is unable to purchase the
Debentures of a holder or holders for shares of Common Stock because any
necessary qualifications or registrations of the shares of Common Stock under
applicable state securities laws cannot be obtained, or because the conditions
to purchasing the Debentures for shares of Common Stock set forth in Section
3.07(e) have not been satisfied, the Company may purchase the Debentures of such
holder or holders for cash. The Company may not change its

                                       32

<PAGE>

election with respect to the consideration (or components or percentages of
components thereof) to be paid once the Company has given its Repurchase Notice
to holders except pursuant to Section 3.07(e) in the event of a failure to
satisfy, prior to the close of business on the Business Day immediately
preceding the Repurchase Date, any condition to the payment of the Repurchase
Price in whole or in part in shares of Common Stock.

         (c)      At least three (3) Business Days before the date of any
Repurchase Notice, the Company shall deliver an Officers' Certificate to the
Trustee specifying:

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

                  (ii)     the information required to be included in the
         Repurchase Notice;

                  (iii)    if the Company elects to pay the Repurchase Price, or
         a specified percentage thereof, in shares of Common Stock, that the
         conditions to such manner of payment set forth in Section 3.07(e) have
         been or will be complied with; and

                  (iv)     whether the Company desires the Trustee to give the

         Repurchase Notice required.

         (d)      If the Company elects to pay the Repurchase Price, or any
percentage thereof, with respect to a Repurchase Date in shares of Common Stock,
the number of shares of Common Stock to be delivered with respect to each $1,000
principal amount of Debentures shall be equal to the quotient obtained by
dividing (i) the dollar amount of the Repurchase Price (not including any
accrued and unpaid interest) to be paid in shares of Common Stock by (ii) (x) in
the case of a repurchase pursuant to Section 3.05, 98.5% of the Market Price
with respect to such Repurchase Date and (y) in the case of a repurchase
pursuant to Section 3.06, 98.5% of the Market Price with respect to such
Repurchase Date; provided that no fractional shares will be delivered.

         (e)      The Company's right to elect to pay some or all of the
Repurchase Price with respect to a Repurchase Date by delivering shares of
Common Stock shall be conditioned upon:

                  (i)      the Company giving timely notice of its election and
         not having previously given notice of an election to pay the Repurchase
         Price with respect to such Repurchase Date entirely in cash;

                  (ii)     the approval for listing of such shares of Common
         Stock on a national securities exchange or the approval for quotation
         of such shares of Common Stock on the Nasdaq Automated Quotation
         System;

                  (iii)    information necessary to calculate the Market Price
         being published in a daily newspaper of national circulation or being
         otherwise readily publicly available;

                  (iv)     the registration of such shares of Common Stock under
         the Securities Act and the Exchange Act, in each case if required;

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

                                       33

<PAGE>

                  (vi)     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 shares of Common Stock are in conformity with
         this Indenture and (B) the shares of Common Stock to be issued by the
         Company in payment of the Repurchase Price in respect of Debentures
         have been duly authorized and, when issued and delivered pursuant to
         the terms of this Indenture in payment of the Repurchase Price, will be
         validly issued, fully paid and nonassessable and free from preemptive
         rights under the Company's Certificate of Incorporation and By-laws and
         the Delaware General Corporation Law, and, in the case of such
         Officers' Certificate, stating that each of the conditions in clauses
         (i) through (v) 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 the condition in clause (iv) above has
         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 Debentures and the Last Reported Sale Price of the Common
         Stock on each Trading Day during the period during which the Market
         Price with respect to such Repurchase Date is to be calculated.

         If the foregoing conditions are not satisfied with respect to a holder
or holders prior to the close of business on the Business Day immediately
preceding the Repurchase Date, the Company shall pay the entire Repurchase Price
of the Debentures of such holder or holders in cash.

         Upon determination of the actual number of shares of Common Stock to be
issued upon repurchase of Debentures, the Company shall be required to
disseminate a press release through Dow Jones & Company, Inc. or Bloomberg
Business News containing this information or publish the information on the
Company's web site or through such other public medium as the Company may use at
that time.

         (f)      All shares of Common Stock delivered upon purchase of the
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.

         (g)      If a holder is paid some or all of the Repurchase Price with
respect to such holder's Debentures in shares of Common Stock, the Company shall
pay any documentary, stamp or similar issue or transfer tax due on such issue of
Common Stock; provided that 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
that of the holder. 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. Nothing herein shall preclude any income tax
withholding required by law or regulations.

         Section 3.08. Conditions and Procedures for Repurchase at Option of
Holders. (a) The Company shall repurchase from the holder thereof, pursuant to
Section 3.05 or Section 3.06, a portion of a Debenture, if the principal amount
of such portion is $1,000 or a whole multiple of $1,000. Provisions of this
Indenture that apply to the repurchase of all of a Debenture also apply to the
repurchase of such portion of such Debenture. Upon presentation of any Debenture
repurchased in part only, the Company shall execute and the Trustee shall
authenticate and make

                                       34

<PAGE>

available for delivery to the holder thereof, at the expense of the Company, a
new Debenture or Debentures, of any authorized denomination, in aggregate
principal amount equal to the portion of the Debentures presented that is not
repurchased.

         (b)      On or prior to a Repurchase Date, the Company will deposit
with the Trustee or with one or more Paying Agents (or, if the Company is acting
as its own Paying Agent, set aside, segregate and hold in trust as provided in
Section 5.04) an amount of cash and/or shares of Common Stock, as applicable,
sufficient to repurchase on the Repurchase Date all the Debentures or portions
thereof to be repurchased on such date at the Repurchase Price; provided that if
such deposit is made on the Repurchase Date, it must be received by the Trustee
or Paying Agent, as the case may be, by 10:00 a.m., New York City time, on such
date.

         If the Trustee or other Paying Agent appointed by the Company, or the
Company or an Affiliate of the Company, if it or such Affiliate is acting as the
Paying Agent, holds cash or shares of Common Stock sufficient to pay the
aggregate Repurchase Price of all the Debentures or portions thereof that are to
be repurchased as of the Repurchase Date, on or after the Repurchase Date, (i)
such Debentures will cease to be outstanding, (ii) interest on such Debentures
will cease to accrue and (iii) all other rights of the holders of such
Debentures will terminate, whether or not book-entry transfer of the Debentures
has been made or the Debentures have been delivered to the Trustee or Paying
Agent, other than the right to receive the Repurchase Price upon delivery of the
Debentures.

         (c)      Upon receipt by the Trustee (or other Paying Agent appointed
by the Company) of a Repurchase Election, the holder of the Debenture in respect
of which such Repurchase Election was given shall (unless such notice is validly
withdrawn) thereafter be entitled to receive solely the Repurchase Price with
respect to such Debenture. Such Repurchase Price shall be paid to such holder,
subject to receipt of funds and/or Debentures by the Trustee (or other Paying
Agent appointed by the Company), promptly (but in no event more than five (5)
Business Days) following the later of (x) the Repurchase Date with respect to
such Debenture (provided the holder has satisfied the conditions in Section
3.05(c) or Section 3.06(c), as applicable) and (y) the time of delivery of such
Debenture to the Trustee (or other Paying Agent appointed by the Company) by the
holder thereof in the manner required by Section 3.05(c) or Section 3.06(c), as
applicable. Debentures in respect of which a Repurchase Election has been given
by the holder thereof may not be converted pursuant to Article 15 hereof on or
after the date of the delivery of such Repurchase Election unless such notice
has first been validly withdrawn.

         (d)      Notwithstanding anything herein to the contrary, any holder
delivering to the office of the Trustee (or other Paying Agent appointed by the
Company) a Repurchase Election shall have the right to withdraw such election at
any time prior to the close of business on the Business Day preceding the
Repurchase Date (or any such later time as may be required by applicable law) by
delivery of a written notice of withdrawal to the Trustee (or other Paying Agent
appointed by the Company) specifying:

                  (i)      the certificate number, if any, of the Debenture in
         respect of which such notice of withdrawal is being submitted, or the
         appropriate Depositary information if the Debenture in respect of which
         such notice of withdrawal is being submitted is represented by a Global
         Debenture,

                                       35

<PAGE>

                  (ii)     the principal amount of the Debenture with respect to
         which such notice of withdrawal is being submitted, and

                  (iii)    the principal amount, if any, of such Debenture which
         remains subject to the original Repurchase Election and which has been
         or will be delivered for repurchase by the Company.

         The Trustee (or other Paying Agent appointed by the Company) shall
promptly notify the Company of the receipt by it of any Repurchase Election or
written notice of withdrawal thereof.

         (e)      The Company will comply with the provisions of Rule 13e-4 and
any other tender offer rules under the Exchange Act to the extent then
applicable in connection with the repurchase rights of the holders of Debentures
in the event of a Fundamental Change or on any Company Repurchase Date. If then
required by applicable law, the Company will file a Schedule TO or any other
schedule required in connection with such repurchase.

         (f)      There shall be no repurchase of any Debentures pursuant to
Section 3.05 or Section 3.06 if there has occurred at any time prior to, and is
continuing on, the Repurchase Date an Event of Default (other than an Event of
Default that is cured by the payment of the Repurchase Price with respect to
such Debentures). The Paying Agent will promptly return to the respective
holders thereof any Debentures (x) with respect to which a Repurchase Election
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 Debentures) in which case, upon such
return, the Repurchase Election with respect thereto shall be deemed to have
been withdrawn.

         (g)      The Trustee (or other Paying Agent appointed by the Company)
shall return to the Company any cash that remains unclaimed as provided in
Section 13.03, for the payment of the Repurchase Price; provided that, to the
extent that the aggregate amount of cash deposited by the Company pursuant to
Section 3.08(b) exceeds the aggregate Repurchase Price of the Debentures or
portions thereof which the Company is obligated to purchase as of the Repurchase
Date, then, unless otherwise agreed in writing with the Company, promptly after
the Business Day following the Repurchase Date, the Trustee shall return any
such excess to the Company.

         (h)      In the case of a reclassification, change, consolidation,
merger, combination, sale or conveyance to which Section 15.06 applies, in which
the Common Stock of the Company is changed or exchanged as a result into the
right to receive stock, securities or other property or assets (including cash),
which includes shares of Common Stock of the Company or shares of common stock
of another Person that are, or upon issuance will be, traded on a United States
national securities exchange or approved for trading on an established automated
over-the-counter trading market in the United States and such shares constitute
at the time such change or exchange becomes effective in excess of 50% of the
aggregate fair market value of such stock, securities or other property or
assets (including cash) (as determined by the Company, which determination shall
be conclusive and binding), then the Person formed by such consolidation or
resulting from such merger or which acquires such assets, as the case may be,
shall execute and deliver to the Trustee a supplemental indenture (accompanied
by an Opinion of Counsel that such supplemental indenture complies with the
Trust Indenture Act as in force at

                                       36

<PAGE>

the date of execution of such supplemental indenture) modifying the provisions
of this Indenture relating to the right of holders of the Debentures to cause
the Company to repurchase the Debentures following a Fundamental Change and the
provisions of this Indenture relating to the Company's option to deliver shares
of Common Stock in payment of the Repurchase Price, including, without
limitation, the applicable provisions of this Article 3 and the definitions of
Common Stock and Fundamental Change, as appropriate, as determined in good faith
by the Company (which determination shall be conclusive and binding), to make
such provisions apply to such other Person if different from the Company and the
common stock issued by such Person (in lieu of the Company and the Common Stock
of the Company).

                                   ARTICLE 4
                           SUBORDINATION OF DEBENTURES

         Section 4.01. Agreement to Subordinate. The Company agrees, and each
Debentureholder by accepting a Debenture agrees, that the Indebtedness, interest
and other obligations of any kind evidenced by the Debentures and this Indenture
are subordinated in right of payment, to the extent and in the manner provided
in this Article 4, to the prior payment in full of all Senior Indebtedness
(whether outstanding on the date hereof or hereafter created, incurred, assumed
or Guaranteed), and that the subordination is for the benefit of the holders of
Senior Indebtedness.

         No provisions of this Article Four shall prevent the occurrence of any
Event of Default.

         Section 4.02. Payment Over of Proceeds Upon Dissolution, Etc. In the
event of:

         (a)      any insolvency or bankruptcy case or proceeding, or any
receivership, liquidation, reorganization or other similar case or proceeding in
connection therewith, relating to the Company or to its creditors, as such, or
to its assets, or

         (b)      any liquidation, dissolution or other winding up of the
Company, whether voluntary or involuntary and whether or not involving
insolvency or bankruptcy, or

         (c)      any assignment for the benefit of creditors or any other
marshalling of assets and liabilities of the Company,

         then and in any such event specified in (a), (b) or (c) above (each
such event, if any, herein sometimes referred to as a ("PROCEEDING") the holders
of Senior Indebtedness of the Company shall be entitled to receive payment in
full of all amounts due or to become due on or in respect of all Senior
Indebtedness of the Company, or provision shall be made for such payment in cash
or cash equivalents or otherwise in manner satisfactory to the holders of Senior
Indebtedness of the Company, before the Debentureholders are entitled to receive
any payment or distribution of any kind or character, whether in cash, property
or securities (including any payment or distribution which may be payable or
deliverable by reason of the payment of any other Indebtedness of the Company
subordinated to the payment of the Debentures), on account of principal or (or
premium, if any) or interest on the Debentures or on account of any purchase or
other acquisition of Debentures by the Company or any subsidiary of the Company,
(all such payments, distributions, purchases and acquisitions, other than the
payment or distribution of stock or securities of the Company referred to in the
second succeeding paragraph, herein

                                       37

<PAGE>

referred to, individually and collectively, as a "SECURITIES PAYMENT"), and to
that end of the holders of Senior Indebtedness of the Company shall be entitled
to receive, for application to the payment thereof, any Securities Payment which
may be payable or deliverable in respect of the Debentures in any such
Proceeding.

         In the event that, notwithstanding the foregoing provisions of this
Section, the Trustee or the Debentureholder shall have received any Securities
Payment before all Senior Indebtedness of the Company is paid in full or payment
thereof provided for in cash or cash equivalents or otherwise in a manner
satisfactory to the holders of Senior Indebtedness of the Company, then and in
such event such Securities Payment shall be paid over or delivered forthwith to
the trustee in bankruptcy, receiver, liquidating trustee, custodian, assignee
agent or other Person making payment or distribution of assets of the Company
for application to the payment of all Senior Indebtedness of the Company
remaining unpaid, to the extent necessary to pay all Senior Indebtedness of the
Company in full, after giving effect to any concurrent payment or distribution
to or for the holders of Senior Indebtedness of the Company.

         For purposes of this Article only, the words "any payment or
distribution of any kind or character, whether in cash, property or securities"
shall not be deemed to include a payment or distribution of stock or securities
of the Company provided for by a plan or reorganization or readjustment
authorized by an order or decree of a court of competent jurisdiction in a
reorganization proceeding under any applicable Bankruptcy Law or of any other
corporation provided for by such plan of reorganization or readjustment which
stock or securities are subordinated in right of payment to all then outstanding
Senior Indebtedness of the Company to substantially the same extent as the
Debentures are so subordinated as provided in this Article. The consolidation of
the Company with, or the merger of the Company into, another Person or the
liquidation or dissolution of the Company following the conveyance or transfer
of all or substantially all of its properties and assets as an entirety to
another Person upon the terms and conditions set forth in Article Twelve shall
not be deemed a Proceeding for the purposes of this Section if the Person formed
by such consolidation or into which the Company is merged or the Person which
acquires by conveyance or transfer such properties and assets as an entirety, as
the case may be, shall, as a part of such consolidation, merger, conveyance or
transfer, comply with the conditions set forth in Article Twelve.

         Section 4.03. No Payment When Senior Indebtedness of the Company in
Default. In the event that any Payment Default (as defined below) shall have
occurred and be continuing, then no Securities Payment shall be made unless and
until such Payment Default shall have been cured or waived or shall have ceased
to exist, or all amounts then due and payable in respect of Senior Indebtedness
of the Company shall have been paid in full, or provision shall have been made
for such payment in cash or cash equivalents or otherwise in a manner
satisfactory to the holders of Senior Indebtedness of the Company.

                  "PAYMENT DEFAULT" means any default in the payment of
principal of (or premium, if any) or interest on any Senior Indebtedness of the
Company when due, whether at the stated maturity of any such payment or by
declaration of acceleration, call for redemption or otherwise.

                                       38

<PAGE>

                  In the event that any Senior Nonmonetary Default (as defined
below) shall have occurred and be continuing, then, upon the receipt by the
Company and the Trustee of written notice of such Senior Nonmonetary Default
from any holder, or agent for the holders, of the Designated Senior Indebtedness
which is the subject of such Senior Nonmonetary Default, no Securities Payment
shall be made during the period (the "PAYMENT BLOCKAGE PERIOD") commencing on
the date of such receipt of such written notice and ending on the earlier of (i)
the date on which such Senior Nonmonetary Default shall have been cured or
waived or shall have ceased to exist or all Designated Senior Indebtedness that
is the subject of such Senior Nonmonetary Default shall have been discharged;
(ii) the 180th day after the date of such receipt of such written notice; and
(iii) the date on which the Payment Blockage Period shall have been terminated
by written notice to the Company or the Trustee from the agent for the
Designated Senior Indebtedness initiating the Payment Blockage Period. No more
than one Payment Blockage Period may be commenced with respect to the Debentures
during any 360-day period and there shall be a period of at least 181
consecutive days in each 360-day period when no Payment Blockage Period is in
effect. For all purposes of this paragraph, no Payment Default or Senior
Nonmonetary Default that existed or was continuing on the date of commencement
of any Payment Blockage Period shall be, or be made, the basis for the
commencement of a subsequent Payment Blockage Period, whether or not within a
period of 360 consecutive days, unless such Payment Default or Senior
Nonmonetary Default shall have been cured for a period of not less than 90
consecutive days.

                  "SENIOR NONMONETARY DEFAULT" means the occurrence or existence
and continuance of any event of default with respect to any Designated Senior
Indebtedness, other than a Payment Default, permitting the holders of such
Designated Senior Indebtedness to declare such Designated Senior Indebtedness
due and payable prior to the date on which it would otherwise become due and
payable.

                  In the event that, notwithstanding the foregoing, the Company
shall make any Securities Payment to the Trustee or any Debentureholder
prohibited by the foregoing provisions of this Section, then and in such event
such Securities Payment shall be paid over and delivered forthwith to the
holders of Senior Indebtedness to the extent necessary to make payment in full
to the holders of all unpaid Senior Indebtedness.

                  The provisions of this Section shall not apply to any
Securities Payment with respect to which Section 4.02 would be applicable..

         Section 4.04. Payment Permitted If No Default. Nothing contained in
this Article or elsewhere in this Indenture or in any of the Debentures shall
prevent (a) the Company from making Securities Payments, or (b) the application
by the Trustee of any money deposited with it hereunder to Securities Payments
or the retention of such Securities Payment by the Debentureholders, at any time
except during the pendency of any Proceeding referred to in Section 4.02 or
under the conditions described in Section 4.03, provided that the Trustee shall
have no liability for any such application if it did not have knowledge that
such Securities Payment was prohibited by the provisions of this Article.

         Section 4.05. Subrogation to Rights of Holders of Designated Senior
Indebtedness of the Company. Upon (but not before) the payment in full of all
Designated Senior Indebtedness, the

                                       39

<PAGE>

holders of the Debentures shall (to the extent that amounts otherwise payable to
such holders have been paid to the holders of Designated Senior Indebtedness
pursuant to this Article 4) be subrogated to the rights of any holder of
Designated Senior Indebtedness to receive any further payments or distributions
applicable to the Designated Senior Indebtedness until the Debentures are paid
in full; and such payments or distributions received by the holders of the
Debentures by reason of such subrogation, which otherwise would be paid or
distributed to the holders of Designated Senior Indebtedness, shall, as between
the Company and its creditors other than the holders of Designated Senior
Indebtedness, on the one hand, and the holders of Debentures, on the other hand,
be deemed to be a payment by the Company on account of Designated Senior
Indebtedness and not on account of the Debentures.

         Section 4.06. Provisions Solely to Define Relative Rights. The
provisions of this Article are and are intended solely for the purpose of
defining the relative rights of the Debentureholders on the one hand and the
holders of Senior Indebtedness of the Company on the other hand. Nothing
contained in this Article or elsewhere in this Indenture or in the Debentures is
intended to or shall (a) impair, as among the Company, its creditors other than
holders of Senior Indebtedness of the Company and the Debentureholders, the
obligation of the Company, which is absolute and unconditional (and which,
subject to the rights under this Article of the holders of Senior Indebtedness
of the Company, is intended to rank equally with all other general obligations
of the Company), to pay to the Debentureholders the principal of (and premium,
if any) and interest on the Debentures as and when the same shall become due and
payable in accordance with their terms; or (b) affect the relative rights
against the Company of the Debentureholders and creditors of the Company other
than the holders of Senior Indebtedness of the Company; or (c) prevent the
Trustee or the Debentureholder from exercising all remedies otherwise permitted
by applicable law upon default under this Indenture, subject to the rights, if
any, under this Article of the holders of Senior Indebtedness of the Company to
receive cash, property and securities otherwise payable or deliverable to the
Trustee or such Debentureholder.

         Section 4.07. Trustee to Effectuate Subordination. Each Debentureholder
by his acceptance thereof authorizes and directs the Trustee on his behalf to
take such action as may be necessary or appropriate to effectuate the
subordination provided in this Article and appoints the Trustee his
attorney-in-fact for any and all such purposes.

         Section 4.08. No Waiver of Subordination Provisions. No right of any
present or future holder of any Senior Indebtedness of the Company to enforce
subordination as herein provided shall at any time in any way be prejudiced or
impaired by any act or failure to act on the part of the Company or by any act
or failure to act, in good faith, by any such holder, or by any noncompliance by
the Company with the terms, provisions and covenants of this Indenture,
regardless of any knowledge thereof any such holder may have or be otherwise
charged with.

         Without in any way limiting the generality of the foregoing paragraph,
the holders of Senior Indebtedness of the Company may, at any time and from time
to time, without the consent of or notice to the Trustee or the
Debentureholders, without incurring responsibility to the Debentureholders and
without impairing or releasing the subordination provided in this Article or the
obligations hereunder of the Debentureholders to the holders of Senior
Indebtedness of the Company, do any one or more of the following: (i) change the
manner, place or terms of payment or extend the time of payment of, or renew or
alter, Senior Indebtedness of the

                                       40

<PAGE>

Company, or otherwise amend or supplement in any manner Senior Indebtedness of
the Company or any instrument evidencing the same or any agreement under which
Senior Indebtedness of the Company is outstanding; (ii) sell, exchange, release
or otherwise deal with any property pledged, mortgaged or otherwise securing
Senior Indebtedness of the Company; (iii) release any Person liable in any
manner for the collection of Senior Indebtedness of the Company; and (iv)
exercise or refrain from exercising any rights against the Company and any other
Person.

         Section 4.09. Notice to Trustee. The Company shall give prompt written
notice to the Trustee of any fact known to the Company which would prohibit the
making of any payment to or by the Trustee in respect of the Debentures;
provided, however, that failure to provide such notice shall not affect the
subordination of the Debentures provided for herein. Notwithstanding the
provisions of this Article or any other provision of this Indenture, the Trustee
shall not be charged with knowledge of the existence of any facts which would
prohibit the making of any payment to or by the Trustee in respect of the
Debentures, unless and until the Trustee shall have received written notice
thereof from the Company or a holder of Senior Indebtedness of the Company or
from any trustee therefor; and, prior to the receipt of any such written notice,
the Trustee, subject to the provisions of Section 8.01, shall be entitled in all
respects to assume that no such facts exist; provided, however, that if the
Trustee shall not have received the notice provided for in this Section at least
three Business Days prior to the date upon which by the terms hereof any money
may become payable for any purpose (including, without limitation, the payment
of the principal of (and premium, if any) or interest on any Debenture), then,
anything herein contained to the contrary notwithstanding, the Trustee shall
have full power and authority to receive such money and to apply the same to the
purpose for which such money was received and shall not be affected by any
notice to the contrary which may be received by it within three Business Days
prior to such date.

                  Subject to the provisions of Section 8.01, the Trustee shall
be entitled to rely on the delivery to it of a written notice by a Person
representing himself to be a holder of Senior Indebtedness of the Company (or a
trustee or other representative therefor) to establish that such notice has been
given by a holder of Senior Indebtedness of the Company (or a trustee therefor).
In the event that the Trustee determines in good faith that further evidence is
required with respect to the right of any Person as a holder of Senior
Indebtedness of the Company to participate in any payment or distribution
pursuant to this Article, the Trustee may request such person to furnish
evidence to the reasonable satisfaction of the Trustee as to the amount of
Senior Indebtedness of the Company held by such Person, the extent to which such
Person is entitled to participate in such payment or distribution and any other
facts pertinent to the rights of such Person under this Article, and if such
evidence is not furnished, the Trustee may defer any payment to such Person
pending judicial determination as to the right of such Person to receive such
payment.

         Section 4.10. Reliance on Judicial Order or Certificate of Liquidating
Agent. Upon any payment or distribution of assets of the Company referred to in
this Article, the Trustee, subject to the provisions of Section 8.01, and the
Debentureholders shall be entitled to rely upon any order or decree entered by
any court of competent jurisdiction in which such proceeding is pending, or a
certificate of the trustee in bankruptcy, receiver, liquidating trustee,
custodian, assignee for the benefit of creditors, agent or other Person making
such payment or distribution,

                                       41

<PAGE>

delivered to the Trustee or to the Debentureholders, for the purpose of
ascertaining the Persons entitled to participate in such payment or
distribution, the holders of the Senior Indebtedness of the Company and other
indebtedness of the Company, the amount thereof or payable thereon, the amount
or amounts paid or distributed thereon and all other facts pertinent thereto or
to this Article.

         Section 4.11. Trustee Not Fiduciary for Holders of Senior Indebtedness
of the Company. The Trustee shall not be deemed to owe any fiduciary duty to the
holders of Senior Indebtedness of the Company and shall not be liable to any
such holders if it shall in good faith mistakenly pay over or distribute to
Debentureholders or to the Company, or to any other Person cash, property or
securities to which any holders of Senior Indebtedness of the Company shall be
entitled by virtue of this Article or otherwise.

         Section 4.12. Rights of Trustee as Holder of Senior Indebtedness of the
Company; Preservation of Trustee's Rights. The Trustee in its individual
capacity shall be entitled to all the rights set forth in this Article with
respect to any Senior Indebtedness of the Company which may at any time be held
by it, to the same extent as any other holder of Senior Indebtedness of the
Company, and nothing in this Indenture shall deprive the Trustee of any of its
rights as such holder.

         Nothing in this Article shall apply to claims of, or payments to, the
Trustee under or pursuant to Section 8.06.

         Section 4.13. Article Applicable to Paying Agents. In case at any time
Paying Agent other than the Trustee shall have been appointed by the Company and
be then acting hereunder, the term "Trustee" as used in this Article shall in
such case (unless the context otherwise requires) be construed as extending to
and including such Paying Agent within its meaning as fully for all intents and
purposes as if such Paying Agent were named in this Article in addition to or in
place of the Trustee; provided, however, that Section 4.14 shall not apply to
the Company, or any Affiliate of the Company if it or such Affiliate acts as
Paying Agent.

                                   ARTICLE 5
                       PARTICULAR COVENANTS OF THE COMPANY

         Section 5.01. Payment of Principal and Interest. The Company covenants
and agrees that it will duly and punctually pay or cause to be paid the
principal of (including any Redemption Price or Repurchase Price pursuant to
Article 3) and interest on each of the Debentures at the places, at the
respective times and in the manner provided herein and in the Debentures.

         Section 5.02. Maintenance of Office or Agency. The Company will
maintain an office or agency in the Borough of Manhattan, The City of New York,
where the Debentures may be surrendered for registration of transfer or exchange
or for presentation for payment or for conversion, redemption or repurchase and
where notices and demands to or upon the Company in respect of the Debentures
and this Indenture may be served. The Company will give prompt written notice to
the Trustee of the location, and any change in the location, of such office or

                                       42

<PAGE>

agency not designated or appointed by the Trustee. 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.

         The Company may also from time to time designate co-registrars and one
or more offices or agencies where the Debentures may be presented or surrendered
for any or all such purposes and may from time to time rescind such
designations. The Company will give prompt written notice of any such
designation or rescission and of any change in the location of any such other
office or agency.

         The Company hereby initially designates the Trustee as Paying Agent,
Debenture Registrar, Custodian and Conversion Agent, and each of the Corporate
Trust Office and the office or agency of the Trustee in the Borough of Manhattan
shall be considered as one such office or agency of the Company for each of the
aforesaid purposes.

         So long as the Trustee is the Debenture Registrar, the Trustee agrees
to mail, or cause to be mailed, the notices set forth in Section 8.10(a) and the
third paragraph of Section 8.11. If co-registrars have been appointed in
accordance with this Section, the Trustee shall mail such notices only to the
Company and the holders of Debentures it can identify from its records.

         Section 5.03. Appointments to Fill Vacancies in Trustee's Office. The
Company, whenever necessary to avoid or fill a vacancy in the office of Trustee,
will appoint, in the manner provided in Section 8.10, a Trustee, so that there
shall at all times be a Trustee hereunder.

         Section 5.04. Provisions as to Paying Agent. (a) If the Company shall
appoint a Paying Agent other than the Trustee, or if the Trustee shall appoint
such a Paying Agent, the Company will cause such Paying Agent to execute and
deliver to the Trustee an instrument in which such Paying Agent shall agree with
the Trustee, subject to the provisions of this Section 5.04:

                  (1)      that it will hold all sums held by it as such agent
         for the payment of the principal of or interest on the Debentures
         (whether such sums have been paid to it by the Company or by any other
         obligor on the Debentures) in trust for the benefit of the holders of
         the Debentures;

                  (2)      that it will give the Trustee notice of any failure
         by the Company (or by any other obligor on the Debentures) to make any
         payment of the principal of or interest on the Debentures when the same
         shall be due and payable; and

                  (3)      that at any time during the continuance of an Event
         of Default, upon request of the Trustee, it will forthwith pay to the
         Trustee all sums so held in trust.

         The Company shall, on or before each due date of the principal of or
interest on the Debentures, deposit with the Paying Agent a sum (in funds which
are immediately available on the due date for such payment) sufficient to pay
such principal or interest, and (unless such Paying Agent is the Trustee) the
Company will promptly notify the Trustee of any failure to take such action;
provided that if such deposit is made on the due date, such deposit shall be
received by the Paying Agent by 10:00 a.m., New York City time, on such date.

                                       43

<PAGE>

         (b)      If the Company shall act as its own Paying Agent, it will, on
or before each due date of the principal of or interest on the Debentures, set
aside, segregate and hold in trust for the benefit of the holders of the
Debentures a sum sufficient to pay such principal or interest so becoming due
and will promptly notify the Trustee of any failure to take such action and of
any failure by the Company (or any other obligor under the Debentures) to make
any payment of the principal of or interest on the Debentures when the same
shall become due and payable.

         (c)      Anything in this Section 5.04 to the contrary notwithstanding,
the Company may, at any time, for the purpose of obtaining a satisfaction and
discharge of this Indenture, or for any other reason, pay or cause to be paid to
the Trustee all sums held in trust by the Company or any Paying Agent hereunder
as required by this Section 5.04, such sums to be held by the Trustee upon the
trusts herein contained and upon such payment by the Company or any Paying Agent
to the Trustee, the Company or such Paying Agent shall be released from all
further liability with respect to such sums.

         (d)      Anything in this Section 5.04 to the contrary notwithstanding,
the agreement to hold sums in trust as provided in this Section 5.04 is subject
to Sections 13.02 and 13.03.

         The Trustee shall not be responsible for the actions of any other
Paying Agents (including the Company if acting as its own Paying Agent) and
shall have no control of any funds held by such other Paying Agents.

         Section 5.05. Existence. Subject to Article 12, the Company will do or
cause to be done all things necessary to preserve and keep in full force and
effect its existence and rights (charter and statutory); provided that the
Company shall not be required to preserve any such right if the Company shall
determine that the preservation thereof is no longer desirable in the conduct of
the business of the Company and that the loss thereof is not disadvantageous in
any material respect to the Debentureholders.

         Section 5.06. Rule 144A Information Requirement. Within the period
prior to the expiration of the holding period applicable to sales thereof under
Rule 144(k) under the Securities Act (or any successor provision), the Company
covenants and agrees that it shall, during any period in which it is not subject
to Section 13 or 15(d) under the Exchange Act, make available to any holder or
beneficial holder of Debentures or any Common Stock issued upon conversion
thereof which continue to be Restricted Securities in connection with any sale
thereof and any prospective purchaser of Debentures or such Common Stock
designated by such holder or beneficial holder, the information required
pursuant to Rule 144A(d)(4) under the Securities Act upon the request of any
holder or beneficial holder of the Debentures or such Common Stock and it will
take such further action as any holder or beneficial holder of such Debentures
or such Common Stock may reasonably request, all to the extent required from
time to time to enable such holder or beneficial holder to sell its Debentures
or Common Stock without registration under the Securities Act within the
limitation of the exemption provided by Rule 144A, as such Rule may be amended
from time to time. Upon the request of any holder or any beneficial holder of
the Debentures or such Common Stock, the Company will deliver to such holder a
written statement as to whether it has complied with such requirements.

                                       44

<PAGE>

         Section 5.07. Stay, Extension and Usury Laws. The Company covenants (to
the extent that it may lawfully do so) that it shall not at any time insist
upon, plead, or in any manner whatsoever claim or take the benefit or advantage
of, any stay, extension or usury law or other law which would prohibit or
forgive the Company from paying all or any portion of the principal of or
interest on the Debentures as contemplated herein, wherever enacted, now or at
any time hereafter in force, or which may affect the covenants or the
performance of this Indenture and the Company (to the extent it may lawfully do
so) hereby expressly waives all benefit or advantage of any such law, and
covenants that it will not, by resort to any such law, hinder, delay or impede
the execution of any power herein granted to the Trustee, but will suffer and
permit the execution of every such power as though no such law had been enacted.

         Section 5.08. Compliance Certificate. The Company shall deliver to the
Trustee, within one hundred twenty (120) days after the end of each fiscal year
of the Company (which fiscal year of the Company is presently the 12 calendar
months ending December 31), a certificate signed by either the principal
executive officer, principal financial officer or principal accounting officer
of the Company, stating whether or not to the best knowledge of the signer
thereof the Company is in default in the performance and observance of any of
the terms, provisions and conditions of this Indenture (without regard to any
period of grace or requirement of notice provided hereunder) and, if the Company
shall be in default, specifying all such defaults and the nature and the status
thereof of which the signer may have knowledge.

         The Company will deliver to the Trustee, promptly upon becoming aware
of (i) any default in the performance or observance of any covenant, agreement
or condition contained in this Indenture, or (ii) any Event of Default, an
Officers' Certificate specifying with particularity such default or Event of
Default and further stating what action the Company has taken, is taking or
proposes to take with respect thereto.

         Any notice required to be given under this Section 5.08 shall be
delivered to a Responsible Officer of the Trustee at its Corporate Trust Office.

         Section 5.09. Additional Amounts Notice. In the event that the Company
is required to pay Additional Amounts to holders of Debentures pursuant to the
Registration Rights Agreement, the Company will provide written notice
("ADDITIONAL AMOUNTS NOTICE") to the Trustee of its obligation to pay Additional
Amounts no later than fifteen (15) days prior to the proposed payment date for
the Additional Amounts, and the Additional Amounts Notice shall set forth the
amount of Additional Amounts to be paid by the Company on such payment date. The
Trustee shall not at any time be under any duty or responsibility to any holder
of Debentures to determine the Additional Amounts, or with respect to the
nature, extent or calculation of the amount of Additional Amounts when made, or
with respect to the method employed in such calculation of the Additional
Amounts.

                                   ARTICLE 6
       DEBENTUREHOLDERS' LISTS AND REPORTS BY THE COMPANY AND THE TRUSTEE

         Section 6.01. Debentureholders' Lists. The Company covenants and agrees
that it will furnish or cause to be furnished to the Trustee, semiannually, not
more than fifteen (15) days after each March 15 and September 15 in each year
beginning with March 15, 2004, and at such

                                       45

<PAGE>

other times as the Trustee may request in writing, within thirty (30) days after
receipt by the Company of any such request (or such lesser time as the Trustee
may reasonably request in order to enable it to timely provide any notice to be
provided by it hereunder), a list in such form as the Trustee may reasonably
require of the names and addresses of the holders of Debentures as of a date not
more than fifteen (15) days (or such other date as the Trustee may reasonably
request in order to so provide any such notices) prior to the time such
information is furnished, except that no such list need be furnished by the
Company to the Trustee so long as the Trustee is acting as the sole Debenture
Registrar.

         Section 6.02. Preservation and Disclosure of Lists. (a) The Trustee
shall preserve, in as current a form as is reasonably practicable, all
information as to the names and addresses of the holders of Debentures contained
in the most recent list furnished to it as provided in Section 6.01 or
maintained by the Trustee in its capacity as Debenture Registrar or co-registrar
in respect of the Debentures, if so acting. The Trustee may destroy any list
furnished to it as provided in Section 6.01 upon receipt of a new list so
furnished.

         (b)      The rights of Debentureholders to communicate with other
holders of Debentures with respect to their rights under this Indenture or under
the Debentures, and the corresponding rights and duties of the Trustee, shall be
as provided by the Trust Indenture Act.

         (c)      Every Debentureholder, by receiving and holding the same,
agrees with the Company and the Trustee that neither the Company nor the Trustee
nor any agent of either of them shall be held accountable by reason of any
disclosure of information as to names and addresses of holders of Debentures
made pursuant to the Trust Indenture Act.

         Section 6.03. Reports by Trustee. (a) Within sixty (60) days after
December 15 of each year commencing with the year 2003, the Trustee shall
transmit to holders of Debentures such reports dated as of December 15 of the
year in which such reports are made concerning the Trustee and its actions under
this Indenture as may be required pursuant to the Trust Indenture Act at the
times and in the manner provided pursuant thereto. In the event that no events
have occurred under the applicable sections of the Trust Indenture Act, the
Trustee shall be under no duty or obligation to provide such reports.

         (b)      A copy of such report shall, at the time of such transmission
to holders of Debentures, be filed by the Trustee with each stock exchange and
automated quotation system upon which the Debentures are listed and with the
Company. The Company will promptly notify the Trustee in writing when the
Debentures are listed on any stock exchange or automated quotation system or
delisted therefrom.

         Section 6.04. Reports by the Company. The Company shall file with the
Trustee (and the Commission if at any time after the Indenture becomes qualified
under the Trust Indenture Act), and transmit to holders of Debentures, such
information, documents and other reports and such summaries thereof, as may be
required pursuant to the Trust Indenture Act at the times and in the manner
provided pursuant to such Act, whether or not the Debentures are governed by
such Act; provided that any such information, documents or reports required to
be filed with the Commission pursuant to Section 13 or 15(d) of the Exchange Act
shall be filed with the Trustee within fifteen (15) days after the same is so
required to be filed with the Commission. Delivery

                                       46

<PAGE>

of such reports, information and documents to the Trustee is for informational
purposes only and the Trustee's receipt of such shall not constitute
constructive notice of any information contained therein or determinable from
information contained therein, including the Company's compliance with any of
its covenants hereunder (as to which the Trustee is entitled to rely exclusively
on Officers' Certificates).

                                   ARTICLE 7
       REMEDIES OF THE TRUSTEE AND DEBENTUREHOLDERS ON AN EVENT OF DEFAULT

         Section 7.01. Events of Default. In case one or more of the following
events (each, an "EVENT OF DEFAULT") (whatever the reason for such Event of
Default and whether it shall be voluntary or involuntary or be effected by
operation of law or pursuant to any judgment, decree or order of any court or
any order, rule or regulation of any administrative or governmental body) shall
have occurred and be continuing:

                  (a)      default in the payment of any installment of interest
         upon any of the Debentures as and when the same shall become due and
         payable, and continuance of such default for a period of thirty (30)
         days whether or not such payment is prohibited by Article 4; or

                  (b)      default in the payment of the principal of any of the
         Debentures as and when the same shall become due and payable either at
         maturity or in connection with any redemption or repurchase, in each
         case pursuant to Article 3, by acceleration or otherwise whether or not
         such payment is prohibited by Article 4; or

                  (c)      default in the Company's obligation to convert the
         Debentures upon the exercise of a holder's rights pursuant to Article
         15; or

                  (d)      default in the Company's obligation to repurchase the
         Debentures at the option of a holder upon a Fundamental Change pursuant
         to Section 3.05 or on specified dates pursuant to Section 3.06; or

                  (e)      failure to provide notice of the occurrence of a
         Fundamental Change on a timely basis as required by Section 3.05; or

                  (f)      default in the Company's obligation to redeem the
         Debentures after it has exercised its option to redeem; or

                  (g)      failure on the part of the Company duly to observe or
         perform any other of the covenants or agreements on the part of the
         Company in the Debentures or in this Indenture (other than a covenant
         or agreement a default in whose performance or whose breach is
         elsewhere in this Section 7.01 specifically dealt with) continued for a
         period of sixty (60) days after the date on which written notice of
         such failure, requiring the Company to remedy the same, shall have been
         given to the Company by the Trustee, or to the Company and a
         Responsible Officer of the Trustee by the holders of at least 25% in
         aggregate principal amount of the Debentures at the time outstanding
         determined in accordance with Section 9.04; or

                                       47

<PAGE>

                  (h)      default by the Company or any of its subsidiaries in
         the payment of the principal or interest on any mortgage, agreement or
         other instrument under which there may be outstanding, or by which
         there may be secured or evidenced, any of the indebtedness of the
         Company or any of its subsidiaries for money borrowed in excess of
         $10,000,000 in the aggregate, whether such indebtedness now exists or
         shall hereafter be created, resulting in such indebtedness becoming or
         being declared due and payable, and such acceleration shall not have
         been rescinded or annulled within thirty (30) days after written notice
         of such acceleration has been received by the Company or such
         subsidiary; or

                  (i)      final unsatisfied judgments not covered by insurance
         aggregating in excess of $10,000,000 rendered against the Company or
         any of its subsidiaries and not stayed, bonded or discharged within a
         period of sixty (60) consecutive days; or

                  (j)      the Company shall commence a voluntary case or other
         proceeding seeking liquidation, reorganization or other relief with
         respect to the Company or its debts under any bankruptcy, insolvency or
         other similar law now or hereafter in effect or seeking the appointment
         of a trustee, receiver, liquidator, custodian or other similar official
         of the Company or any substantial part of the property of the Company,
         or shall consent to any such relief or to the appointment of or taking
         possession by any such official in an involuntary case or other
         proceeding commenced against the Company, or shall make a general
         assignment for the benefit of creditors, or shall fail generally to pay
         its debts as they become due; or

                  (k)      an involuntary case or other proceeding shall be
         commenced against the Company seeking liquidation, reorganization or
         other relief with respect to the Company or its debts under any
         bankruptcy, insolvency or other similar law now or hereafter in effect
         or seeking the appointment of a trustee, receiver, liquidator,
         custodian or other similar official of the Company or any substantial
         part of the property of the Company, and such involuntary case or other
         proceeding remains undismissed or unstayed and in effect for a period
         of sixty (60) consecutive days;

then, and in each and every such case (other than an Event of Default specified
in Section 7.01(j) or 7.01(k)), unless the principal of all of the 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 Debentures then
outstanding hereunder determined in accordance with Section 9.04, by notice in
writing to the Company (and to the Trustee if given by Debentureholders), may
declare the principal of all the Debentures and the interest accrued 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 Debentures contained to the contrary notwithstanding. If an Event of
Default specified in Section 7.01(j) or 7.01(k) occurs, the principal of all the
Debentures and the interest accrued thereon shall be immediately and
automatically due and payable without necessity of further action. This
provision, however, is subject to the conditions that if, at any time after the
principal of the Debentures shall have been so declared due and payable, and
before any judgment or decree for the payment of the monies due shall have been
obtained or entered as hereinafter provided, the Company shall pay or shall
deposit with the Trustee a sum sufficient to pay all matured installments of
interest upon all

                                       48

<PAGE>

Debentures and the principal of any and all Debentures which shall have become
due otherwise than by acceleration (with interest on overdue installments of
interest (to the extent that payment of such interest is enforceable under
applicable law) and on such principal at the rate borne by the Debentures, to
the date of such payment or deposit) and amounts due to the Trustee pursuant to
Section 8.06, and if any and all defaults under this Indenture, other than the
nonpayment of principal of and accrued interest on Debentures which shall have
become due by acceleration, shall have been cured or waived pursuant to Section
7.07, then and in every such case the holders of a majority in aggregate
principal amount of the Debentures then outstanding, by written notice to the
Company and to the Trustee, may waive all defaults or Events of Default and
rescind and annul such declaration and its consequences; but no such waiver or
rescission and annulment shall extend to or shall affect any subsequent default
or Event of Default, or shall impair any right consequent thereon. The Company
shall notify in writing a Responsible Officer of the Trustee, promptly upon
becoming aware thereof, of any Event of Default.

         In case the Trustee shall have proceeded to enforce any right under
this Indenture and such proceedings shall have been discontinued or abandoned
because of such waiver or rescission and annulment or for any other reason or
shall have been determined adversely to the Trustee, then and in every such case
the Company, the holders of Debentures, and the Trustee shall be restored
respectively to their several positions and rights hereunder, and all rights,
remedies and powers of the Company, the holders of Debentures, and the Trustee
shall continue as though no such proceeding had been taken.

         Section 7.02. Payments of Debentures on Default; Suit Therefor. The
Company covenants that (a) in case default shall be made in the payment of any
installment of interest upon any of the Debentures as and when the same shall
become due and payable, and such default shall have continued for a period of
thirty (30) days, or (b) in case default shall be made in the payment of the
principal of any of the Debentures as and when the same shall have become due
and payable, whether at maturity of the Debentures or in connection with any
redemption, repurchase, acceleration, declaration or otherwise, then, upon
demand of the Trustee, the Company will pay to the Trustee, for the benefit of
the holders of the Debentures, the whole amount that then shall have become due
and payable on all such Debentures for principal or interest, as the case may
be, with interest upon the overdue principal and (to the extent that payment of
such interest is enforceable under applicable law) upon the overdue installments
of interest at the rate borne by the Debentures, and, in addition thereto, such
further amount as shall be sufficient to cover the costs and expenses of
collection, including reasonable compensation to the Trustee, its agents,
attorneys and counsel, and all other amounts due the Trustee under Section 8.06.
Until such demand by the Trustee, the Company may pay the principal of and
interest on the Debentures to the registered holders, whether or not the
Debentures are overdue.

         In case the Company shall fail forthwith to pay such amounts upon such
demand, the Trustee, in its own name and as trustee of an express trust, shall
be entitled and empowered to institute any actions or proceedings at law or in
equity for the collection of the sums so due and unpaid, and may prosecute any
such action or proceeding to judgment or final decree, and may enforce any such
judgment or final decree against the Company or any other obligor on the
Debentures and collect in the manner provided by law out of the property of the
Company or any other obligor on the Debentures wherever situated the monies
adjudged or decreed to be payable.

                                       49

<PAGE>

         In case there shall be pending proceedings for the bankruptcy or for
the reorganization of the Company or any other obligor on the Debentures under
Title 11 of the United States Code, or any other applicable law, or in case a
receiver, assignee or trustee in bankruptcy or reorganization, liquidator,
sequestrator or similar official shall have been appointed for or taken
possession of the Company or such other obligor, the property of the Company or
such other obligor, or in the case of any other judicial proceedings relative to
the Company or such other obligor upon the Debentures, or to the creditors or
property of the Company or such other obligor, the Trustee, irrespective of
whether the principal of the Debentures shall then be due and payable as therein
expressed or by declaration or otherwise and irrespective of whether the Trustee
shall have made any demand pursuant to the provisions of this Section 7.02,
shall be entitled and empowered, by intervention in such proceedings or
otherwise, to file and prove a claim or claims for the whole amount of principal
and interest owing and unpaid in respect of the Debentures, and, in case of any
judicial proceedings, to file such proofs of claim and other papers or documents
as may be necessary or advisable in order to have the claims of the Trustee and
of the Debentureholders allowed in such judicial proceedings relative to the
Company or any other obligor on the Debentures, its or their creditors, or its
or their property, and to collect and receive any monies or other property
payable or deliverable on any such claims, and to distribute the same after the
deduction of any amounts due the Trustee under Section 8.06, and to take any
other action with respect to such claims, including participating as a member of
any official committee of creditors, as it reasonably deems necessary or
advisable, and, unless prohibited by law or applicable regulations, and any
receiver, assignee or trustee in bankruptcy or reorganization, liquidator,
custodian or similar official is hereby authorized by each of the
Debentureholders to make such payments to the Trustee, and, in the event that
the Trustee shall consent to the making of such payments directly to the
Debentureholders, to pay to the Trustee any amount due it for reasonable
compensation, expenses, advances and disbursements, including counsel fees and
expenses incurred by it up to the date of such distribution. To the extent that
such payment of reasonable compensation, expenses, advances and disbursements
out of the estate in any such proceedings shall be denied for any reason,
payment of the same shall be secured by a Lien on, and shall be paid out of, any
and all distributions, dividends, monies, securities and other property which
the holders of the Debentures may be entitled to receive in such proceedings,
whether in liquidation or under any plan of reorganization or arrangement or
otherwise.

         All rights of action and of asserting claims under this Indenture, or
under any of the Debentures, may be enforced by the Trustee without the
possession of any of the Debentures, or the production thereof at any trial or
other proceeding relative thereto, and any such suit or proceeding instituted by
the Trustee shall be brought in its own name as trustee of an express trust, and
any recovery of judgment shall, after provision for the payment of the
reasonable compensation, expenses, disbursements and advances of the Trustee,
its agents and counsel, be for the ratable benefit of the holders of the
Debentures.

         In any proceedings brought by the Trustee (and in any proceedings
involving the interpretation of any provision of this Indenture to which the
Trustee shall be a party), the Trustee shall be held to represent all the
holders of the Debentures, and it shall not be necessary to make any holders of
the Debentures parties to any such proceedings.

                                       50

<PAGE>

         Section 7.03. Application of Monies Collected by Trustee. Any monies
collected by the Trustee pursuant to this Article 7 shall be applied in the
order following, at the date or dates fixed by the Trustee for the distribution
of such monies, upon presentation of the several Debentures, and stamping
thereon the payment, if only partially paid, and upon surrender thereof, if
fully paid:

                  FIRST: To the payment of all amounts due the Trustee under
         Section 8.06;

                  SECOND: In case the principal of the outstanding Debentures
         shall not have become due and be unpaid, to the payment of interest on
         the Debentures in default in the order of the maturity of the
         installments of such interest, with interest (to the extent that such
         interest has been collected by the Trustee) upon the overdue
         installments of interest at the rate borne by the Debentures, such
         payments to be made ratably to the Persons entitled thereto;

                  THIRD: In case the principal of the outstanding Debentures
         shall have become due, by declaration or otherwise, and be unpaid, to
         the payment of the whole amount then owing and unpaid upon the
         Debentures for principal and interest, with interest on the overdue
         principal and (to the extent that such interest has been collected by
         the Trustee) upon overdue installments of interest at the rate borne by
         the Debentures, and in case such monies shall be insufficient to pay in
         full the whole amounts so due and unpaid upon the Debentures, then to
         the payment of such principal and interest without preference or
         priority of principal over interest, or of interest over principal, or
         of any installment of interest over any other installment of interest,
         or of any Debenture over any other Debenture, ratably to the aggregate
         of such principal and accrued and unpaid interest; and

                  FOURTH: To the payment of the remainder, if any, to the
         Company or any other Person lawfully entitled thereto.

         Section 7.04. Proceedings by Debentureholder. No holder of any
Debenture shall have any right by virtue of or by reference to any provision of
this Indenture to institute any suit, action or proceeding in equity or at law
upon or under or with respect to this Indenture, or for the appointment of a
receiver, trustee, liquidator, custodian or other similar official, or for any
other remedy hereunder, unless such holder previously shall have given to the
Trustee written notice of an Event of Default and of the continuance thereof, as
hereinbefore provided, and unless also the holders of not less than 25% in
aggregate principal amount of the Debentures then outstanding shall have made
written request upon the Trustee to institute such action, suit or proceeding in
its own name as Trustee hereunder and shall have offered to the Trustee such
reasonable security or indemnity satisfactory to the Trustee as it may require
against the costs, expenses and liabilities to be incurred therein or thereby,
and the Trustee for sixty (60) days after its receipt of such notice, request
and offer of reasonable indemnity, shall have neglected or refused to institute
any such action, suit or proceeding and no direction inconsistent with such
written request shall have been given to the Trustee pursuant to Section 7.07;
it being understood and intended, and being expressly covenanted by the taker
and holder of every Debenture with every other taker and holder and the Trustee,
that no one or more holders of Debentures shall have any right in any manner
whatever by virtue of or by reference to any provision of this Indenture to
affect, disturb

                                       51

<PAGE>

or prejudice the rights of any other holder of Debentures, or to obtain or seek
to obtain priority over or preference to any other such holder, or to enforce
any right under this Indenture, except in the manner herein provided and for the
equal, ratable and common benefit of all holders of Debentures (except as
otherwise provided herein). For the protection and enforcement of this Section
7.04, each and every Debentureholder and the Trustee shall be entitled to such
relief as can be given either at law or in equity.

         Notwithstanding any other provision of this Indenture and any provision
of any Debenture, the right of any holder of any Debenture to receive payment of
the principal of (including any Redemption Price or Repurchase Price pursuant to
Article 3) and accrued interest on such Debenture on or after the respective due
dates expressed in such Debenture, or to institute suit for the enforcement of
any such payment on or after such respective dates against the Company, shall
not be impaired or affected without the consent of such holder.

         Anything in this Indenture or the Debentures to the contrary
notwithstanding, the holder of any Debenture, without the consent of either the
Trustee or the holder of any other Debenture, on its own behalf and for its own
benefit, may enforce, and may institute and maintain any proceeding suitable to
enforce, its rights of conversion as provided herein.

         Section 7.05. Proceedings by Trustee. In case of an Event of Default,
the Trustee may, in its discretion, proceed to protect and enforce the rights
vested in it by this Indenture by such appropriate judicial proceedings as are
necessary to protect and enforce any of such rights, either by suit in equity or
by action at law or by proceeding in bankruptcy or otherwise, whether for the
specific enforcement of any covenant or agreement contained in this Indenture or
in aid of the exercise of any power granted in this Indenture, or to enforce any
other legal or equitable right vested in the Trustee by this Indenture or by
law.

         Section 7.06. Remedies Cumulative and Continuing. Except as provided in
Section 2.06, all powers and remedies given by this Article 7 to the Trustee or
to the Debentureholders shall, to the extent permitted by law, be deemed
cumulative and not exclusive of any thereof or of any other powers and remedies
available to the Trustee or the holders of the Debentures, by judicial
proceedings or otherwise, to enforce the performance or observance of the
covenants and agreements contained in this Indenture, and no delay or omission
of the Trustee or of any holder of any of the Debentures to exercise any right
or power accruing upon any default or Event of Default occurring and continuing
as aforesaid shall impair any such right or power, or shall be construed to be a
waiver of any such default or any acquiescence therein, and, subject to the
provisions of Section 7.04, every power and remedy given by this Article 7 or by
law to the Trustee or to the Debentureholders may be exercised from time to
time, and as often as shall be deemed expedient, by the Trustee or by the
Debentureholders.

         Section 7.07. Direction of Proceedings and Waiver of Defaults by
Majority of Debentureholders. The holders of a majority in aggregate principal
amount of the Debentures at the time outstanding determined in accordance with
Section 9.04 shall have the right to direct the time, method and place of
conducting any proceeding for any remedy available to the Trustee or exercising
any trust or power conferred on the Trustee; provided that (a) such direction
shall not be in conflict with any rule of law or with this Indenture, (b) the
Trustee may take any other action which is not inconsistent with such direction
and (c) the Trustee may decline to take any

                                       52

<PAGE>

action that would benefit some Debentureholders to the detriment of other
Debentureholders. The holders of a majority in aggregate principal amount of the
Debentures at the time outstanding determined in accordance with Section 9.04
may, on behalf of the holders of all of the Debentures, waive any past default
or Event of Default hereunder and its consequences, except (i) a default in the
payment of interest on, or the principal of, the Debentures, (ii) a failure by
the Company to convert any Debentures into Common Stock, (iii) a default in the
payment of the Redemption Price pursuant to Section 3.03, (iv) a default in the
payment of the Fundamental Change Repurchase Price pursuant to Section 3.05 or
Company Repurchase Price pursuant to Section 3.06 or (v) a default in respect of
a covenant or provisions hereof which under Article 11 cannot be modified or
amended without the consent of the holders of each or all Debentures then
outstanding or affected thereby. Upon any such waiver, the Company, the Trustee
and the holders of the Debentures shall be restored to their former positions
and rights hereunder; but no such waiver shall extend to any subsequent or other
default or Event of Default or impair any right consequent thereon. Whenever any
default or Event of Default hereunder shall have been waived as permitted by
this Section 7.07, said default or Event of Default shall for all purposes of
the Debentures and this Indenture be deemed to have been cured and to be not
continuing; but no such waiver shall extend to any subsequent or other default
or Event of Default or impair any right consequent thereon.

         Section 7.08. Notice of Defaults. The Trustee shall, within ninety (90)
days after a Responsible Officer of the Trustee has knowledge of the occurrence
of a default, mail to all Debentureholders, as the names and addresses of such
holders appear upon the Debenture Register, notice of all defaults known to a
Responsible Officer, unless such defaults shall have been cured or waived before
the giving of such notice; provided that except in the case of default in the
payment of the principal of or interest on any of the Debentures, the Trustee
shall be protected in withholding such notice if and so long as a trust
committee of directors and/or Responsible Officers of the Trustee in good faith
determines that the withholding of such notice is in the interests of the
Debentureholders. For the purpose of this Section 7.08, the term "DEFAULT" means
any event which is, or after notice or lapse of time or both would become, an
Event of Default.

         Section 7.09. Undertaking to Pay Costs. All parties to this Indenture
agree, and each holder of any Debenture by its acceptance thereof shall be
deemed to have agreed, that any court may, in its discretion, require, in any
suit for the enforcement of any right or remedy under this Indenture, or in any
suit against the Trustee for any action taken or omitted by it as Trustee, the
filing by any party litigant in such suit of an undertaking to pay the costs of
such suit and that such court may in its discretion assess reasonable costs,
including reasonable attorneys' fees and expenses, against any party litigant in
such suit, having due regard to the merits and good faith of the claims or
defenses made by such party litigant; provided that the provisions of this
Section 7.09 (to the extent permitted by law) shall not apply to any suit
instituted by the Trustee, to any suit instituted by any Debentureholder, or
group of Debentureholders, holding in the aggregate more than ten percent in
principal amount of the Debentures at the time outstanding determined in
accordance with Section 9.04, or to any suit instituted by any Debentureholder
for the enforcement of the payment of the principal of or interest on any
Debenture on or after the due date expressed in such Debenture or to any suit
for the enforcement of the right to convert any Debenture in accordance with the
provisions of Article 15.

                                       53

<PAGE>

                                    ARTICLE 8
                                   THE TRUSTEE

         Section 8.01. Duties and Responsibilities of Trustee. The Trustee,
prior to the occurrence of an Event of Default and after the curing of all
Events of Default which may have occurred, undertakes to perform such duties and
only such duties as are specifically set forth in this Indenture. In case an
Event of Default has occurred (which has not been cured or waived), the Trustee
shall exercise such of the rights and powers vested in it by this Indenture, and
use the same degree of care and skill in their exercise, as a prudent person
would exercise or use under the circumstances in the conduct of his own affairs.

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

                  (a)      prior to the occurrence of an Event of Default and
         after the curing or waiving of all Events of Default which may have
         occurred:

                           (i)      the duties and obligations of the Trustee
                  shall be determined solely by the express provisions of this
                  Indenture and the Trust Indenture Act, and the Trustee shall
                  not be liable except for the performance of such duties and
                  obligations as are specifically set forth in this Indenture
                  and no implied covenants or obligations shall be read into
                  this Indenture and the Trust Indenture Act against the
                  Trustee; and

                           (ii)     in the absence of bad faith on the part of
                  the Trustee, the Trustee may conclusively rely as to the truth
                  of the statements and the correctness of the opinions
                  expressed therein, upon any certificates or opinions furnished
                  to the Trustee and conforming to the requirements of this
                  Indenture; but, in the case of any such certificates or
                  opinions which by any provisions hereof are specifically
                  required to be furnished to the Trustee, the Trustee shall be
                  under a duty to examine the same to determine whether or not
                  they conform to the requirements of this Indenture (but need
                  not confirm or investigate the accuracy of mathematical
                  calculations or other facts stated therein);

                  (b)      the Trustee shall not be liable for any error of
         judgment made in good faith by a Responsible Officer or Officers of the
         Trustee, unless the Trustee was negligent in ascertaining the pertinent
         facts;

                  (c)      the Trustee shall not be liable with respect to any
         action taken or omitted to be taken by it in good faith in accordance
         with the written direction of the holders of not less than a majority
         in principal amount of the Debentures at the time outstanding
         determined as provided in Section 9.04 relating to the time, method and
         place of conducting any proceeding for any remedy available to the
         Trustee, or exercising any trust or power conferred upon the Trustee,
         under this Indenture;

                  (d)      the Trustee shall not be liable in respect of any
         payment (as to the correctness of amount, entitlement to receive or any
         other matters relating to payment) or

                                       54

<PAGE>

         notice effected by the Company or any Paying Agent or any records
         maintained by any co-registrar with respect to the Debentures; and

                  (e)      if any party fails to deliver a notice relating to an
         event the fact of which, pursuant to this Indenture, requires notice to
         be sent to the Trustee, the Trustee may conclusively rely on its
         failure to receive such notice as reason to act as if no such event
         occurred.

         The Trustee shall not be deemed to have knowledge or notice of any
default (as defined in Section 7.08) or Event of Default hereunder unless a
Responsible Officer of the Trustee shall have received at the Corporate Trust
Office written notice of such default or Event of Default from the Company or
the holders of at least 10% in aggregate principal amount of the Debentures and
such notice refers to such default or Event of Default, the Debentures and the
Indenture.

         None of the provisions contained in this Indenture shall require the
Trustee to expend or risk its own funds or otherwise incur personal financial
liability in the performance of any of its duties or in the exercise of any of
its rights or powers, if there is reasonable ground for believing that the
repayment of such funds or adequate indemnity against such risk or liability is
not reasonably assured to it.

         Whether or not therein provided, every provision of this Indenture
relating to the conduct or affecting the liability of, or affording protection
to, the Trustee shall be subject to the provisions of this Section 8.01.

         Section 8.02. Reliance on Documents, Opinions, Etc. Except as otherwise
provided in Section 8.01:

                  (a)      the Trustee may conclusively rely and shall be
         protected in acting upon any resolution, certificate, statement,
         instrument, opinion, report, notice, request, consent, order, bond,
         debenture, note, coupon or other paper or document (whether in its
         original or facsimile form) believed by it in good faith to be genuine
         and to have been signed or presented by the proper party or parties;

                  (b)      any request, direction, order or demand of the
         Company mentioned herein shall be sufficiently evidenced by an
         Officers' Certificate (unless other evidence in respect thereof be
         herein specifically prescribed); and any resolution of the Board of
         Directors may be evidenced to the Trustee by a copy thereof certified
         by the Secretary or an Assistant Secretary of the Company;

                  (c)      the Trustee may consult with counsel of its own
         selection and any advice or Opinion of Counsel shall be full and
         complete authorization and protection in respect of any action taken or
         omitted by it hereunder in good faith and in accordance with such
         advice or Opinion of Counsel;

                  (d)      the Trustee shall be under no obligation to exercise
         any of the rights or powers vested in it by this Indenture at the
         request, order or direction of any of the Debentureholders pursuant to
         the provisions of this Indenture, unless such

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<PAGE>

         Debentureholders shall have offered to the Trustee reasonable security
         or indemnity satisfactory to it against the costs, expenses and
         liabilities which may be incurred therein or thereby;

                  (e)      the Trustee shall not be bound to make any
         investigation into the facts or matters stated in any resolution,
         certificate, statement, instrument, opinion, report, notice, request,
         direction, consent, order, bond, debenture or other paper or document,
         but the Trustee may make such further inquiry or investigation into
         such facts or matters as it may see fit, and, if the Trustee shall
         determine to make such further inquiry or investigation, it shall be
         entitled to examine the books, records and premises of the Company,
         personally or by agent or attorney;

                  (f)      the Trustee may execute any of the trusts or powers
         hereunder or perform any duties hereunder either directly or by or
         through agents or attorneys and the Trustee shall not be responsible
         for any misconduct or negligence on the part of any agent or attorney
         appointed by it with due care hereunder;

                  (g)      the Trustee shall not be liable for any action taken,
         suffered or omitted to be taken by it in good faith and reasonably
         believed by it to be authorized or within the discretion or rights or
         powers conferred upon it by this Indenture;

                  (h)      the rights, privileges, protections, immunities and
         benefits given to the Trustee, including, without limitation, its right
         to be indemnified, are extended to, and shall be enforceable by, the
         Trustee in each of its capacities hereunder, and each agent, custodian
         and other Person employed to act hereunder;

                  (i)      the Trustee may request that the Company deliver an
         Officers' Certificate setting forth the names of individuals and/or
         titles of officers authorized at such time to take specified actions
         pursuant to this Indenture, which Officers' Certificate may be signed
         by any person authorized to sign an Officers' Certificate, including
         any person specified as so authorized in any such certificate
         previously delivered and not superseded;

                  (j)      whenever in the administration of this Indenture the
         Trustee shall deem it desirable that a matter be proved or established
         prior to taking, suffering or omitting any action hereunder, the
         Trustee (unless other evidence be herein specifically prescribed) may,
         in the absence of bad faith on its part, conclusively rely upon an
         Officers' Certificate; and

                  (k)      the Trustee may, before taking any action or
         refraining from taking any action under the Indenture, require that an
         indemnity satisfactory to it be furnished for the reimbursement of all
         expenses to which it may be put and to protect it against all
         liability, including costs incurred in defending itself against any and
         all charges, claims, complaints, allegations, assertions or demands of
         any nature whatsoever, except liability which is adjudicated to be a
         result of the Trustee's negligence or misconduct in connection with any
         such action.

         Section 8.03. No Responsibility for Recitals, Etc. The recitals
contained herein and in the Debentures (except in the Trustee's certificate of
authentication) shall be taken as the

                                       56

<PAGE>

statements of the Company, and the Trustee assumes no responsibility for the
correctness of the same. The Trustee makes no representations as to the validity
or sufficiency of this Indenture or of the Debentures. The Trustee shall not be
accountable for the use or application by the Company of any Debentures or the
proceeds of any Debentures authenticated and delivered by the Trustee in
conformity with the provisions of this Indenture.

         Section 8.04. Trustee, Paying Agents, Conversion Agents or Registrar
May Own Debentures. The Trustee, any Paying Agent, any Conversion Agent or
Debenture Registrar, in its individual or any other capacity, may become the
owner or pledgee of Debentures with the same rights it would have if it were not
Trustee, Paying Agent, Conversion Agent or Debenture Registrar.

         Section 8.05. Monies to Be Held in Trust. Subject to the provisions of
Section 13.03, all monies received by the Trustee shall, until used or applied
as herein provided, be held in trust for the purposes for which they were
received. Money held by the Trustee in trust hereunder need not be segregated
from other funds except to the extent required by law. The Trustee shall be
under no liability for interest on any money received by it hereunder except as
may be agreed in writing from time to time by the Company and the Trustee.

         Section 8.06. Compensation and Expenses of Trustee. The Company
covenants and agrees to pay to the Trustee from time to time, and the Trustee
shall be entitled to, such compensation for all services rendered by it
hereunder in any capacity (which shall not be limited by any provision of law in
regard to the compensation of a trustee of an express trust) as mutually agreed
to from time to time in writing between the Company and the Trustee, and the
Company will pay or reimburse the Trustee upon its request for all reasonable
expenses, disbursements and advances reasonably incurred or made by the Trustee
in accordance with any of the provisions of this Indenture (including the
reasonable compensation and the expenses and disbursements of its counsel and of
all Persons not regularly in its employ) except any such expense, disbursement
or advance as may arise from its negligence or willful misconduct. The Company
also covenants to indemnify the Trustee and any predecessor Trustee (or any
officer, director or employee of the Trustee), in any capacity under this
Indenture and its agents and any authenticating agent for, and to hold them
harmless against, any and all loss, liability, damage, claim or expense
including taxes (other than taxes based on the income of the Trustee) incurred
without negligence or willful misconduct on the part of the Trustee or such
officers, directors, employees and agent or authenticating agent, as the case
may be, and arising out of or in connection with the acceptance or
administration of this trust or in any other capacity hereunder, including the
costs and expenses of defending themselves against any claim (whether asserted
by the Company, any holder or any other Person) of liability in connection with
the exercise or performance of any of its powers or duties hereunder. The
obligations of the Company under this Section 8.06 to compensate or indemnify
the Trustee and to pay or reimburse the Trustee for expenses, disbursements and
advances shall be secured by a lien prior to that of the Debentures upon all
property and funds held or collected by the Trustee as such, except funds held
in trust for the benefit of the holders of particular Debentures. The obligation
of the Company under this Section shall survive the satisfaction and discharge
of this Indenture.

         When the Trustee and its agents and any authenticating agent incur
expenses or render services after an Event of Default specified in Section
7.01(j) or Section 7.01(k) occurs with

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<PAGE>

respect to the Company, the expenses and the compensation for the services are
intended to constitute expenses of administration under any bankruptcy,
insolvency or similar laws.

         Section 8.07. Officers' Certificate as Evidence. Except as otherwise
provided in Section 8.01, whenever in the administration of the provisions of
this Indenture the Trustee shall deem it necessary or desirable that a matter be
proved or established prior to taking or omitting any action hereunder, such
matter (unless other evidence in respect thereof be herein specifically
prescribed) may, in the absence of bad faith or willful misconduct on the part
of the Trustee, be deemed to be conclusively proved and established by an
Officers' Certificate delivered to the Trustee.

         Section 8.08. Conflicting Interests of Trustee. If the Trustee has or
shall acquire a conflicting interest within the meaning of the Trust Indenture
Act, the Trustee shall either eliminate such interest or resign, to the extent
and in the manner provided by, and subject to the provisions of, the Trust
Indenture Act and this Indenture.

         Section 8.09. Eligibility of Trustee. There shall at all times be a
Trustee hereunder which shall be a Person that is eligible pursuant to the Trust
Indenture Act to act as such and has a combined capital and surplus of at least
$50,000,000 (or if such Person is a member of a bank holding company system, its
bank holding company shall have a combined capital and surplus of at least
$50,000,000). If such Person publishes reports of condition at least annually,
pursuant to law or to the requirements of any supervising or examining
authority, then for the purposes of this Section the combined capital and
surplus of such Person shall be deemed to be its combined capital and surplus as
set forth in its most recent report of condition so published. If at any time
the Trustee shall cease to be eligible in accordance with the provisions of this
Section 8.09, it shall resign immediately in the manner and with the effect
hereinafter specified in this Article.

         Section 8.10. Resignation or Removal of Trustee. (a) The Trustee may at
any time resign by giving written notice of such resignation to the Company and
to the holders of Debentures. Upon receiving such notice of resignation, the
Company shall promptly appoint a successor trustee by written instrument, in
duplicate, executed by order of the Board of Directors, one copy of which
instrument shall be delivered to the resigning Trustee and one copy to the
successor trustee. If no successor trustee shall have been so appointed and have
accepted appointment sixty (60) days after the mailing of such notice of
resignation to the Debentureholders, the resigning Trustee may, upon ten (10)
Business Days' notice to the Company and the Debentureholders, may petition, at
the expense of the Company, any court of competent jurisdiction for the
appointment of a successor trustee, or, if any Debentureholder who has been a
bona fide holder of a Debenture or Debentures for at least six months may,
subject to the provisions of Section 7.09, on behalf of himself and all others
similarly situated, petition any such court for the appointment of a successor
trustee. Such court may thereupon, after such notice, if any, as it may deem
proper and prescribe, appoint a successor trustee.

         (b)      In case at any time any of the following shall occur:

                  (i)      the Trustee shall fail to comply with Section 8.08
         after written request therefor by the Company or by any Debentureholder
         who has been a bona fide holder of a Debenture or Debentures for at
         least six months; or

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<PAGE>

                  (ii)     the Trustee shall cease to be eligible in accordance
         with the provisions of Section 8.09 and shall fail to resign after
         written request therefor by the Company or by any such Debentureholder;
         or

                  (iii)    the Trustee shall become incapable of acting, or
         shall be adjudged a bankrupt or insolvent, or a receiver of the Trustee
         or of its property shall be appointed, or any public officer shall take
         charge or control of the Trustee or of its property or affairs for the
         purpose of rehabilitation, conservation or liquidation,

then, in any such case, the Company may remove the Trustee and appoint a
successor trustee by written instrument, in duplicate, executed by order of the
Board of Directors, one copy of which instrument shall be delivered to the
Trustee so removed and one copy to the successor trustee, or, subject to the
provisions of Section 7.09, any Debentureholder who has been a bona fide holder
of a Debenture or Debentures for at least six months may, on behalf of himself
and all others similarly situated, petition any court of competent jurisdiction
for the removal of the Trustee and the appointment of a successor trustee;
provided that if no successor Trustee shall have been appointed and have
accepted appointment sixty (60) days after either the Company or the
Debentureholders has removed the Trustee, or the Trustee resigns, the Trustee so
removed may petition, at the expense of the Company, any court of competent
jurisdiction for an appointment of a successor trustee. Such court may
thereupon, after such notice, if any, as it may deem proper and prescribe,
remove the Trustee and appoint a successor trustee.

         (c)      The holders of a majority in aggregate principal amount of the
Debentures at the time outstanding may at any time remove the Trustee and
nominate a successor trustee which shall be deemed appointed as successor
trustee unless, within ten (10) days after notice to the Company of such
nomination, the Company objects thereto, in which case the Trustee so removed or
any Debentureholder, or if such Trustee so removed or any Debentureholder fails
to act, the Company, upon the terms and conditions and otherwise as in Section
8.10(a) provided, may petition any court of competent jurisdiction for an
appointment of a successor trustee.

         (d)      Any resignation or removal of the Trustee and appointment of a
successor trustee pursuant to any of the provisions of this Section 8.10 shall
become effective upon acceptance of appointment by the successor trustee as
provided in Section 8.11.

         Section 8.11. Acceptance by Successor Trustee. Any successor trustee
appointed as provided in Section 8.10 shall execute, acknowledge and deliver to
the Company and to its predecessor trustee an instrument accepting such
appointment hereunder, and thereupon the resignation or removal of the
predecessor trustee shall become effective and such successor trustee, without
any further act, deed or conveyance, shall become vested with all the rights,
powers, duties and obligations of its predecessor hereunder, with like effect as
if originally named as trustee herein; but, nevertheless, on the written request
of the Company or of the successor trustee, the trustee ceasing to act shall,
upon payment of any amount then due it pursuant to the provisions of Section
8.06, execute and deliver an instrument transferring to such successor trustee
all the rights and powers of the trustee so ceasing to act. Upon request of any
such successor trustee, the Company shall execute any and all instruments in
writing for more fully and certainly vesting in and confirming to such successor
trustee all such rights and powers. Any trustee ceasing to act shall,
nevertheless, retain a lien upon all property and funds held or

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<PAGE>

collected by such trustee as such, except for funds held in trust for the
benefit of holders of particular Debentures, to secure any amounts then due it
pursuant to the provisions of Section 8.06.

         No successor trustee shall accept appointment as provided in this
Section 8.11 unless, at the time of such acceptance, such successor trustee
shall be qualified under the provisions of Section 8.08 and be eligible under
the provisions of Section 8.09.

         Upon acceptance of appointment by a successor trustee as provided in
this Section 8.11, the Company (or the former trustee, at the written direction
of the Company) shall mail or cause to be mailed notice of the succession of
such trustee hereunder to the holders of Debentures at their addresses as they
shall appear on the Debenture Register. If the Company fails to mail such notice
within ten (10) days after acceptance of appointment by the successor trustee,
the successor trustee shall cause such notice to be mailed at the expense of the
Company.

         Section 8.12. Succession by Merger. Any Person into which the Trustee
may be merged or converted or with which it may be consolidated, or any Person
resulting from any merger, conversion or consolidation to which the Trustee
shall be a party, or any Person succeeding to all or substantially all of the
corporate trust business of the Trustee (including any trust created by this
Indenture), shall be the successor to the Trustee hereunder without the
execution or filing of any paper or any further act on the part of any of the
parties hereto; provided that, in the case of any Person succeeding to all or
substantially all of the corporate trust business of the Trustee, such Person
shall be qualified under the provisions of Section 8.08 and eligible under the
provisions of Section 8.09.

         In case at the time such successor to the Trustee shall succeed to the
trusts created by this Indenture, any of the Debentures shall have been
authenticated but not delivered, any such successor to the Trustee may adopt the
certificate of authentication of any predecessor trustee or authenticating agent
appointed by such predecessor trustee, and deliver such Debentures so
authenticated; and in case at that time any of the Debentures shall not have
been authenticated, any successor to the Trustee or any authenticating agent
appointed by such successor trustee may authenticate such Debentures in the name
of the successor trustee; and in all such cases such certificates shall have the
full force that is provided in the Debentures or in this Indenture; provided
that the right to adopt the certificate of authentication of any predecessor
Trustee or authenticate Debentures in the name of any predecessor Trustee shall
apply only to its successor or successors by merger, conversion or
consolidation.

         Section 8.13. Preferential Collection of Claims. If and when the
Trustee shall be or become a creditor of the Company (or any other obligor upon
the Debentures), the Trustee shall be subject to the provisions of the Trust
Indenture Act regarding the collection of the claims against the Company (or any
such other obligor).

                                   ARTICLE 9
                              THE DEBENTUREHOLDERS

         Section 9.01. Action by Debentureholders. Whenever in this Indenture it
is provided that the holders of a specified percentage in aggregate principal
amount of the Debentures may take

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any action (including the making of any demand or request, the giving of any
notice, consent or waiver or the taking of any other action), the fact that at
the time of taking any such action, the holders of such specified percentage
have joined therein may be evidenced (a) by any instrument or any number of
instruments of similar tenor executed by Debentureholders in person or by agent
or proxy appointed in writing, or (b) by the record of the holders of Debentures
voting in favor thereof at any meeting of Debentureholders duly called and held
in accordance with the provisions of Article 10, or (c) by a combination of such
instrument or instruments and any such record of such a meeting of
Debentureholders. Whenever the Company or the Trustee solicits the taking of any
action by the holders of the Debentures, the Company or the Trustee may fix in
advance of such solicitation, a date as the record date for determining holders
entitled to take such action. The record date shall he not more than fifteen
(15) days prior to the date of commencement solicitation of such action.

         Section 9.02. Proof of Execution by Debentureholders. Subject to the
provisions of Section 8.01, 8.02 and 10.05, proof of the execution of any
instrument by a Debentureholder or its agent or proxy shall be sufficient if
made in accordance with such reasonable rules and regulations as may be
prescribed by the Trustee or in such manner as shall be satisfactory to the
Trustee. The holding of Debentures shall be proved by the registry of such
Debentures or by a certificate of the Debenture Registrar.

         The record of any Debentureholders' meeting shall be proved in the
manner provided in Section 10.06.

         Section 9.03. Who Are Deemed Absolute Owners. The Company, the Trustee,
any Paying Agent, any Conversion Agent and any Debenture Registrar may deem the
Person in whose name such Debenture shall be registered upon the Debenture
Register to be, and may treat it as, the absolute owner of such Debenture
(whether or not such Debenture shall be overdue and notwithstanding any notation
of ownership or other writing thereon made by any Person other than the Company
or any Debenture Registrar) for the purpose of receiving payment of or on
account of the principal of and interest on such Debenture, for conversion of
such Debenture and for all other purposes; and neither the Company nor the
Trustee nor any Paying Agent nor any Conversion Agent nor any Debenture
Registrar shall be affected by any notice to the contrary. All such payments so
made to any holder for the time being, or upon his order, shall be valid, and,
to the extent of the sum or sums so paid, effectual to satisfy and discharge the
liability for monies payable upon any such Debenture.

         Section 9.04. Company-owned Debentures Disregarded. In determining
whether the holders of the requisite aggregate principal amount of Debentures
have concurred in any direction, consent, waiver or other action under this
Indenture, Debentures which are owned by the Company or any other obligor on the
Debentures or any Affiliate of the Company or any other obligor on the
Debentures shall be disregarded and deemed not to be outstanding for the purpose
of any such determination; provided that for the purposes of determining whether
the Trustee shall be protected in relying on any such direction, consent, waiver
or other action, only Debentures which a Responsible Officer knows are so owned
shall be so disregarded. Debentures so owned which have been pledged in good
faith may be regarded as outstanding for the purposes of this Section 9.04 if
the pledgee shall establish to the satisfaction of the Trustee the pledgee's
right to vote such Debentures and that the pledgee is not the Company, any other

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<PAGE>

obligor on the Debentures or any Affiliate of the Company or any such other
obligor. In the case of a dispute as to such right, any decision by the Trustee
taken upon the advice of counsel shall fully protect the Trustee. Upon request
of the Trustee, the Company shall furnish to the Trustee promptly an Officers'
Certificate listing and identifying all Debentures, if any, known by the Company
to be owned or held by or for the account of any of the above described Persons,
and, subject to Section 8.01, the Trustee shall be entitled to accept such
Officers' Certificate as conclusive evidence of the facts therein set forth and
of the fact that all Debentures listed therein are outstanding for the purpose
of any such determination.

         Section 9.05. Revocation of Consents, Future Holders Bound. At any time
prior to (but not after) the evidencing to the Trustee, as provided in Section
9.01, of the taking of any action by the holders of the percentage in aggregate
principal amount of the Debentures specified in this Indenture in connection
with such action, any holder of a Debenture which is shown by the evidence to be
included in the Debentures the holders of which have consented to such action
may, by filing written notice with the Trustee at its Corporate Trust Office and
upon proof of holding as provided in Section 9.02, revoke such action so far as
concerns such Debenture. Except as aforesaid, any such action taken by the
holder of any Debenture shall be conclusive and binding upon such holder and
upon all future holders and owners of such Debenture and of any Debentures
issued in exchange or substitution therefor, irrespective of whether any
notation in regard thereto is made upon such Debenture or any Debenture issued
in exchange or substitution therefor.

                                   ARTICLE 10
                          MEETINGS OF DEBENTUREHOLDERS

         Section 10.01. Purpose of Meetings. A meeting of Debentureholders may
be called at any time and from time to time pursuant to the provisions of this
Article 10 for any of the following purposes:

                  (1)      to give any notice to the Company or to the Trustee
         or to give any directions to the Trustee permitted under this
         Indenture, or to consent to the waiving of any default or Event of
         Default hereunder and its consequences, or to take any other action
         authorized to be taken by Debentureholders pursuant to any of the
         provisions of Article 7;

                  (2)      to remove the Trustee and nominate a successor
         trustee pursuant to the provisions of Article 8;

                  (3)      to consent to the execution of an indenture or
         indentures supplemental hereto pursuant to the provisions of Section
         11.02; or

                  (4)      to take any other action authorized to be taken by or
         on behalf of the holders of any specified aggregate principal amount of
         the Debentures under any other provision of this Indenture or under
         applicable law.

         Section 10.02. Call of Meetings by Trustee. The Trustee may at any time
call a meeting of Debentureholders to take any action specified in Section
10.01, to be held at such time and at such place as the Trustee shall determine.
Notice of every meeting of the Debentureholders,

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<PAGE>

setting forth the time and the place of such meeting and in general terms the
action proposed to be taken at such meeting and the establishment of any record
date pursuant to Section 9.01, shall be mailed to holders of Debentures at their
addresses as they shall appear on the Debenture Register. Such notice shall also
be mailed to the Company. Such notices shall be mailed not less than 20 nor more
than ninety (90) days prior to the date fixed for the meeting.

         Any meeting of Debentureholders shall be valid without notice if the
holders of all Debentures then outstanding are present in person or by proxy or
if notice is waived before or after the meeting by the holders of all Debentures
outstanding, and if the Company and the Trustee are either present by duly
authorized representatives or have, before or after the meeting, waived notice.

         Section 10.03. Call of Meetings by Company or Debentureholders. In case
at any time the Company, pursuant to a resolution of its Board of Directors, or
the holders of at least 10% in aggregate principal amount of the Debentures then
outstanding, shall have requested the Trustee to call a meeting of
Debentureholders, by written request setting forth in reasonable detail the
action proposed to be taken at the meeting, and the Trustee shall not have
mailed the notice of such meeting within twenty (20) days after receipt of such
request, then the Company or such Debentureholders may determine the time and
the place for such meeting and may call such meeting to take any action
authorized in Section 10.01, by mailing notice thereof as provided in Section
10.02.

         Section 10.04. Qualifications for Voting. To be entitled to vote at any
meeting of Debentureholders a person shall (a) be a holder of one or more
Debentures on the record date pertaining to such meeting or (b) be a person
appointed by an instrument in writing as proxy by a holder of one or more
Debentures on the record date pertaining to such meeting. The only persons who
shall be entitled to be present or to speak at any meeting of Debentureholders
shall be the persons entitled to vote at such meeting and their counsel and any
representatives of the Trustee and its counsel and any representatives of the
Company and its counsel.

         Section 10.05. Regulations. Notwithstanding any other provisions of
this Indenture, the Trustee may make such reasonable regulations as it may deem
advisable for any meeting of Debentureholders, in regard to proof of the holding
of Debentures and of the appointment of proxies, and in regard to the
appointment and duties of inspectors of votes, the submission and examination of
proxies, certificates and other evidence of the right to vote, and such other
matters concerning the conduct of the meeting as it shall think fit.

         The Trustee shall, by an instrument in writing, appoint a temporary
chairman of the meeting, unless the meeting shall have been called by the
Company or by Debentureholders as provided in Section 10.03, in which case the
Company or the Debentureholders calling the meeting, as the case may be, shall
in like manner appoint a temporary chairman. A permanent chairman and a
permanent secretary of the meeting shall be elected by vote of the holders of a
majority in principal amount of the Debentures represented at the meeting and
entitled to vote at the meeting.

         Subject to the provisions of Section 9.04, at any meeting each
Debentureholder or proxyholder shall be entitled to one vote for each $1,000
principal amount of Debentures held or

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<PAGE>

represented by him; provided that no vote shall be cast or counted at any
meeting in respect of any Debenture challenged as not outstanding and ruled by
the chairman of the meeting to be not outstanding. The chairman of the meeting
shall have no right to vote other than by virtue of Debentures held by him or
instruments in writing as aforesaid duly designating him as the proxy to vote on
behalf of other Debentureholders. Any meeting of Debentureholders duly called
pursuant to the provisions of Section 10.02 or 10.03 may be adjourned from time
to time by the holders of a majority of the aggregate principal amount of
Debentures represented at the meeting, whether or not constituting a quorum, and
the meeting may be held as so adjourned without further notice.

         Section 10.06. Voting. The vote upon any resolution submitted to any
meeting of Debentureholders shall be by written ballot on which shall be
subscribed the signatures of the holders of Debentures or of their
representatives by proxy and the outstanding principal amount of the Debentures
held or represented by them. The permanent chairman of the meeting shall appoint
two inspectors of votes who shall count all votes cast at the meeting for or
against any resolution and who shall make and file with the secretary of the
meeting their verified written reports in duplicate of all votes cast at the
meeting. A record in duplicate of the proceedings of each meeting of
Debentureholders shall be prepared by the secretary of the meeting and there
shall be attached to said record the original reports of the inspectors of votes
on any vote by ballot taken thereat and affidavits by one or more persons having
knowledge of the facts setting forth a copy of the notice of the meeting and
showing that said notice was mailed as provided in Section 10.02. The record
shall show the principal amount of the Debentures voting in favor of or against
any resolution. The record shall be signed and verified by the affidavits of the
permanent chairman and secretary of the meeting and one of the duplicates shall
be delivered to the Company and the other to the Trustee to be preserved by the
Trustee, the latter to have attached thereto the ballots voted at the meeting.

         Any record so signed and verified shall be conclusive evidence of the
matters therein stated.

         Section 10.07. No Delay of Rights by Meeting. Nothing contained in this
Article 10 shall be deemed or construed to authorize or permit, by reason of any
call of a meeting of Debentureholders or any rights expressly or impliedly
conferred hereunder to make such call, any hindrance or delay in the exercise of
any right or rights conferred upon or reserved to the Trustee or to the
Debentureholders under any of the provisions of this Indenture or of the
Debentures.

                                   ARTICLE 11
                             SUPPLEMENTAL INDENTURES

         Section 11.01. Supplemental Indentures Without Consent of
Debentureholders. The Company, when authorized by the resolutions of the Board
of Directors, and the Trustee may, from time to time, and at any time enter into
an indenture or indentures supplemental hereto for one or more of the following
purposes:

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<PAGE>

                  (a)      make provision with respect to the conversion rights
         of the holders of Debentures pursuant to the requirements of Section
         15.06 or the repurchase obligations of the Company pursuant to the
         requirements of Section 3.08(h);

                  (b)      to convey, transfer, assign, mortgage or pledge to
         the Trustee as security for the Debentures, any property or assets;

                  (c)      to add a guarantor with respect to the Debentures;

                  (d)      to evidence the succession of another Person to the
         Company, or successive successions, and the assumption by the successor
         Person of the covenants, agreements and obligations of the Company
         pursuant to Article 12;

                  (e)      to surrender any of its rights or powers under the
         Indenture (including, without limitation, the right to pay any part of
         the Repurchase Price of the Debentures with shares of Common Stock as
         provided for by the Indenture existing on a date after the date of such
         amendment);

                  (f)      to add to the covenants of the Company such further
         covenants, restrictions or conditions for the benefit of the holders of
         Debentures, and to make the occurrence, or the occurrence and
         continuance, of a default in any such additional covenants,
         restrictions or conditions a default or an Event of Default permitting
         the enforcement of all or any of the several remedies provided in this
         Indenture as herein set forth; provided that in respect of any such
         additional covenant, restriction or condition, such supplemental
         indenture may provide for a particular period of grace after default
         (which period may be shorter or longer than that allowed in the case of
         other defaults) or may provide for an immediate enforcement upon such
         default or may limit the remedies available to the Trustee upon such
         default;

                  (g)      to make any changes or modifications necessary in
         connection with the registration of the Debentures under the Securities
         Act as contemplated by the Registration Rights Agreement, so long as
         any such change or modification shall not materially adversely affect
         the interests of the holders of the Debentures;

                  (h)      to provide for the issuance under this Indenture of
         Debentures in coupon form (including Debentures registrable as to
         principal only) and to provide for exchangeability of such Debentures
         with the Debentures issued hereunder in fully registered form and to
         make all appropriate changes for such purpose;

                  (i)      to cure any ambiguity or to correct or supplement any
         provision contained herein or in any supplemental indenture that may be
         defective or inconsistent with any other provisions contained herein or
         in any supplemental indenture, or to make such other provision in
         regard to matters or questions arising under this Indenture that shall
         not materially adversely affect the interests of the holders of the
         Debentures;

                  (j)      to evidence and provide for the acceptance of
         appointment hereunder by a successor Trustee with respect to the
         Debentures;

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                  (k)      to modify, eliminate or add to the provisions of this
         Indenture to such extent as shall be necessary to effect the
         qualifications of this Indenture or any supplemental indenture under
         the Trust Indenture Act, or under any similar federal statute hereafter
         enacted; or

                  (l)      make other changes to the Indenture or forms or terms
         of the Debentures, provided no such change individually or in the
         aggregate with all other such changes has or will have a material
         adverse effect on the interests of the Debentureholders.

         Upon the written request of the Company, accompanied by a copy of the
resolutions of the Board of Directors certified by the Company's Secretary or
Assistant Secretary authorizing the execution of any supplemental indenture, the
Trustee is hereby authorized to join with the Company in the execution of any
such supplemental indenture, to make any further appropriate agreements and
stipulations that may be therein contained and to accept the conveyance,
transfer and assignment of any property thereunder, but the Trustee shall not be
obligated to, but may in its discretion, enter into any supplemental indenture
that affects the Trustee's own rights, duties or immunities under this Indenture
or otherwise.

         Any supplemental indenture authorized by the provisions of this Section
11.01 may be executed by the Company and the Trustee without the consent of the
holders of any of the Debentures at the time outstanding, notwithstanding any of
the provisions of Section 11.02.

         Notwithstanding any other provision of the Indenture or the Debentures,
the Registration Rights Agreement and the obligation to pay Additional Amounts
thereunder may be amended, modified or waived in accordance with the provisions
of the Registration Rights Agreement.

         Section 11.02. Supplemental Indenture with Consent of Debentureholders.
With the consent (evidenced as provided in Article 9) of the holders of at least
a majority in aggregate principal amount of the Debentures at the time
outstanding, the Company, when authorized by the resolutions of the Board of
Directors, and the Trustee may, from time to time and at any time, enter into an
indenture or indentures supplemental hereto for the purpose of adding any
provisions to or changing in any manner or eliminating any of the provisions of
this Indenture or any supplemental indenture or of modifying in any manner the
rights of the holders of the Debentures; provided that no such supplemental
indenture shall (i) extend the Stated Maturity of any Debenture, or reduce the
rate or extend the time of payment of interest thereon, or reduce the principal
amount thereof, or reduce any amount payable on redemption or repurchase
thereof, or impair the right of any Debentureholder to institute suit for the
payment thereof, or make the principal thereof or interest thereon payable in
any coin or currency other than that provided in the Debentures, or affect the
obligation of the Company to redeem any Debenture on a Redemption Date in a
manner adverse to the holders of Debentures, or affect the obligation of the
Company to repurchase any Debenture upon the happening of a Fundamental Change
in a manner adverse to the holders of Debentures, or affect the obligation of
the Company to repurchase any Debenture on a Company Repurchase Date in a manner
adverse to the holders of Debentures, or impair the right to convert the
Debentures into shares of Common Stock subject to the terms set forth herein,
including Section 15.06, or reduce the number of shares of Common Stock or other
property receivable upon conversion, in each case, without the consent of the
holder of each Debenture so affected, or modify any of the provisions of this
Section 11.02 or

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Section 7.07, except to increase any such percentage or to provide that certain
other provisions of this Indenture cannot be modified or waived without the
consent of the holder of each Debenture so affected, or change any obligation of
the Company to maintain an office or agency in the places and for the purposes
set forth in Section 5.02, or reduce the quorum or voting requirements set forth
in Article 10 or (ii) reduce the aforesaid percentage of Debentures, the holders
of which are required to consent to any such supplemental indenture, without the
consent of the holders of all Debentures then outstanding.

         Upon the written request of the Company, accompanied by a copy of the
resolutions of the Board of Directors certified by its Secretary or Assistant
Secretary authorizing the execution of any such supplemental indenture, and upon
the filing with the Trustee of evidence of the consent of Debentureholders as
aforesaid, the Trustee shall join with the Company in the execution of such
supplemental indenture unless such supplemental indenture affects the Trustee's
own rights, duties or immunities under this Indenture or otherwise, in which
case the Trustee may in its discretion, but shall not be obligated to, enter
into such supplemental indenture.

         It shall not be necessary for the consent of the Debentureholders under
this Section 11.02 to approve the particular form of any proposed supplemental
indenture, but it shall be sufficient if such consent shall approve the
substance thereof.

         Section 11.03. Effect of Supplemental Indenture. Any supplemental
indenture executed pursuant to the provisions of this Article 11 shall comply
with the Trust Indenture Act, as then in effect, provided that this Section
11.03 shall not require such supplemental indenture or the Trustee to be
qualified under the Trust Indenture Act prior to the time such qualification is
in fact required under the terms of the Trust Indenture Act or the Indenture has
been qualified under the Trust Indenture Act, nor shall it constitute any
admission or acknowledgment by any party to such supplemental indenture that any
such qualification is required prior to the time such qualification is in fact
required under the terms of the Trust Indenture Act or the Indenture has been
qualified under the Trust Indenture Act. Upon the execution of any supplemental
indenture pursuant to the provisions of Article 11, this Indenture shall be and
shall be deemed to be modified and amended in accordance therewith and the
respective rights, limitation of rights, obligations, duties and immunities
under this Indenture of the Trustee, the Company and the holders of Debentures
shall thereafter be determined, exercised and enforced hereunder, subject in all
respects to such modifications and amendments and all the terms and conditions
of any such supplemental indenture shall be and shall be deemed to be part of
the terms and conditions of this Indenture for any and all purposes.

         Section 11.04. Notation on Debentures. Debentures authenticated and
delivered after the execution of any supplemental indenture pursuant to the
provisions of this Article 11 may bear a notation in form approved by the
Trustee as to any matter provided for in such supplemental indenture. If the
Company or the Trustee shall so determine, new Debentures so modified as to
conform, in the opinion of the Trustee and the Board of Directors, to any
modification of this Indenture contained in any such supplemental indenture may,
at the Company's expense, be prepared and executed by the Company, authenticated
by the Trustee (or an authenticating agent duly appointed by the Trustee
pursuant to Section 16.13) and delivered in exchange for the Debentures then
outstanding, upon surrender of such Debentures then outstanding.

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         Section 11.05. Evidence of Compliance of Supplemental Indenture to Be
Furnished to Trustee. Prior to entering into any supplemental indenture, the
Trustee shall be provided with an Officers' Certificate and an Opinion of
Counsel as conclusive evidence that any supplemental indenture executed pursuant
hereto complies with the requirements of this Article 11 and is otherwise
authorized or permitted by this Indenture.

                                   ARTICLE 12
                CONSOLIDATION, MERGER, SALE, CONVEYANCE AND LEASE

         Section 12.01. Company May Consolidate on Certain Terms. Subject to the
provisions of Section 12.02, the Company shall not consolidate or merge with or
into any other Person or Persons (whether or not affiliated with the Company),
nor shall the Company or its successor or successors be a party or parties to
successive consolidations or mergers, nor shall the Company sell, convey,
transfer or lease the property and assets of the Company substantially as an
entirety, to any other Person (whether or not affiliated with the Company),
unless: (i) the Company is the surviving Person, or the resulting, surviving or
transferee Person is a corporation organized and existing under the laws of the
United States of America, any state thereof or the District of Columbia; (ii)
upon any such consolidation, merger, sale, conveyance, transfer or lease, the
due and punctual payment of the principal of and interest on all of the
Debentures, according to their tenor and the due and punctual performance and
observance of all of the covenants and conditions of this Indenture to be
performed by the Company, shall be expressly assumed, by supplemental indenture
satisfactory in form to the Trustee, executed and delivered to the Trustee by
the Person (if other than the Company) formed by such consolidation, or into
which the Company shall have been merged, or by the Person that shall have
acquired or leased such property, and such supplemental indenture shall provide
for the applicable conversion rights set forth in Section 15.06; and (iii)
immediately after giving effect to the transaction described above, no Event of
Default, and no event which, after notice or lapse of time or both, would become
an Event of Default, shall have occurred and be continuing.

         Section 12.02. Successor to Be Substituted. In case of any such
consolidation, merger, sale, conveyance, transfer or lease and upon the
assumption by the successor Person, by supplemental indenture, executed and
delivered to the Trustee and satisfactory in form to the Trustee, of the due and
punctual payment of the principal of and interest on all of the Debentures and
the due and punctual performance of all of the covenants and conditions of this
Indenture to be performed by the Company, such successor Person shall succeed to
and be substituted for the Company, with the same effect as if it had been named
herein as the party of this first part. Such successor Person thereupon may
cause to be signed, and may issue either in its own name or in the name of
Quanta Services, Inc. any or all of the Debentures, issuable hereunder that
theretofore shall not have been signed by the Company and delivered to the
Trustee; and, upon the order of such successor Person instead of the Company and
subject to all the terms, conditions and limitations in this Indenture
prescribed, the Trustee shall authenticate and shall deliver, or cause to be
authenticated and delivered, any Debentures that previously shall have been
signed and delivered by the officers of the Company to the Trustee for
authentication, and any Debentures that such successor Person thereafter shall
cause to be signed and delivered to the Trustee for that purpose. All the
Debentures so issued shall in all respects have the same legal rank and benefit
under this Indenture as the Debentures theretofore or thereafter issued in
accordance with the terms of this Indenture as though all of such Debentures had
been issued at

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the date of the execution hereof. In the event of any such consolidation,
merger, sale, conveyance, transfer or lease, the Person named as the "COMPANY"
in the first paragraph of this Indenture or any successor that shall thereafter
have become such in the manner prescribed in this Article 12 may be dissolved,
wound up and liquidated at any time thereafter and such Person shall be released
from its liabilities as obligor and maker of the Debentures and from its
obligations under this Indenture.

         In case of any such consolidation, merger, sale, conveyance, transfer
or lease, such changes in phraseology and form (but not in substance) may be
made in the Debentures thereafter to be issued as may be appropriate.

         Section 12.03. Opinion of Counsel to Be Given Trustee. The Trustee
shall receive an Officers' Certificate and an Opinion of Counsel as conclusive
evidence that any such consolidation, merger, sale, conveyance, transfer or
lease and any such assumption complies with the provisions of this Article 12.

                                   ARTICLE 13
                     SATISFACTION AND DISCHARGE OF INDENTURE

         Section 13.01. Discharge of Indenture. When (a) the Company shall
deliver to the Trustee for cancellation all Debentures theretofore authenticated
(other than any Debentures that have been destroyed, lost or stolen and in lieu
of or in substitution for which other Debentures shall have been authenticated
and delivered) and not theretofore canceled, or (b) all the Debentures not
theretofore canceled or delivered to the Trustee for cancellation shall have
become due and payable and the Company shall deposit with the Trustee, in trust,
cash or, if expressly permitted by the terms of the Debentures or the Indenture,
Common Stock sufficient to pay all amounts due and owing on Debentures (other
than any Debentures that shall have been mutilated, destroyed, lost or stolen
and in lieu of or in substitution for which other Debentures shall have been
authenticated and delivered) not theretofore canceled or delivered to the
Trustee for cancellation, accompanied by a verification report, as to the
sufficiency of the deposited amount, from an independent certified accountant or
other financial professional satisfactory to the Trustee, and if in either case
the Company shall also pay or cause to be paid all other sums payable hereunder
by the Company, then this Indenture shall cease to be of further effect (except
as to (i) remaining rights of registration of transfer, substitution and
exchange and conversion of Debentures, (ii) rights hereunder of Debentureholders
to receive payments of principal of and interest on the Debentures and the other
rights, duties and obligations of Debentureholders, as beneficiaries hereof with
respect to the amounts, if any, so deposited with the Trustee and (iii) the
rights, powers, duties, obligations and immunities of the Trustee hereunder),
and the Trustee, on written demand of the Company accompanied by an Officers'
Certificate and an Opinion of Counsel as required by Section 16.06 and at the
cost and expense of the Company, shall execute proper instruments acknowledging
satisfaction of and discharging this Indenture; the Company, however, hereby
agrees to reimburse the Trustee for any costs or expenses thereafter reasonably
and properly incurred by the Trustee and to compensate the Trustee for any
services thereafter reasonably and properly rendered by the Trustee in
connection with this Indenture or the Debentures.

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         Section 13.02. Paying Agent to Repay Monies Held. Upon the satisfaction
and discharge of this Indenture, all monies then held by any Paying Agent of the
Debentures (other than the Trustee) shall, upon written request of the Company,
be repaid to it or paid to the Trustee, and thereupon such Paying Agent shall be
released from all further liability with respect to such monies.

         Section 13.03. Return of Unclaimed Monies. Subject to the requirements
of applicable law, any monies deposited with or paid to the Trustee for payment
of the principal of or interest on Debentures and not applied but remaining
unclaimed by the holders of Debentures for two years after the date upon which
the principal of or interest on such Debentures, as the case may be, shall have
become due and payable, shall be repaid to the Company by the Trustee on demand
and all liability of the Trustee shall thereupon cease with respect to such
monies; and the holder of any of the Debentures shall thereafter look only to
the Company for any payment that such holder may be entitled to collect unless
an applicable abandoned property law designates another Person.

                                   ARTICLE 14
         IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS AND DIRECTORS

         Section 14.01. Indenture and Debentures Solely Corporate Obligations.
No recourse for the payment of the principal of or interest on any Debenture, or
for any claim based thereon or otherwise in respect thereof, and no recourse
under or upon any obligation, covenant or agreement of the Company in this
Indenture or in any supplemental indenture or in any Debenture, or because of
the creation of any indebtedness represented thereby, shall be had against any
incorporator, stockholder, employee, agent, officer, director or subsidiary, as
such, past, present or future, of the Company or of any successor corporation,
either directly or through the Company or any successor corporation, whether by
virtue of any constitution, statute or rule of law, or by the enforcement of any
assessment or penalty or otherwise; it being expressly understood that all such
liability is hereby expressly waived and released as a condition of, and as a
consideration for, the execution of this Indenture and the issue of the
Debentures.

                                   ARTICLE 15
                            CONVERSION OF DEBENTURES

         Section 15.01. Right to Convert. (a) Subject to and upon compliance
with the provisions of this Indenture, prior to October 1, 2023, the holder of
any Debenture shall have the right, at such holder's option, to convert the
principal amount of the Debenture, or any portion of such principal amount which
is a multiple of $1,000, into fully paid and non-assessable shares of Common
Stock (as such shares shall then be constituted) at the Conversion Rate in
effect at such time, by surrender of the Debenture so to be converted in whole
or in part, together with any required funds, under the circumstances described
in this Section 15.01 and in the manner provided in Section 15.02. The
Debentures shall be convertible only during the following periods upon the
occurrence of one of the following events:

                  (i)      during any fiscal quarter after the fiscal quarter
         ending December 31, 2003 if the Last Reported Sale Price of the Common
         Stock for at least twenty (20) Trading Days during the period of thirty
         (30) consecutive Trading Days ending on the first

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         Trading Day of such fiscal quarter equals or exceeds 120% of the
         Conversion Price on such first Trading Day;

                  (ii)     in the event that the Company calls the Debentures
         for redemption, at any time prior to the close of business on the
         second Business Day immediately preceding the Redemption Date; provided
         that only those Debentures that are called for redemption may be
         converted following such an event;

                  (iii)    as provided in Section (b) of this Section 15.01; or

                  (iv)     during the five (5) Business Day period immediately
         after any five (5) consecutive Trading Day period in which the Trading
         Price per $1,000 principal amount of the Debentures for each day of
         such five (5) day measurement period was less than 98% of the product
         of the Last Reported Sale Price of the Common Stock on the applicable
         date and the Conversion Rate.

         Notwithstanding the foregoing, if, on the date of any conversion
pursuant to Section 15.01(a)(iv) on or after October 1, 2018, the Last Reported
Sale Price of the Common Stock on the Trading Day before the Conversion Date is
greater than 100% but less than 120% of the Conversion Price, the holders of
Debentures surrendered for conversion shall receive, in lieu of Common Stock
based on the Conversion Rate, cash or Common Stock or a combination of cash and
Common Stock, at the Company's option, with a value equal to the principal
amount of the Debentures being converted plus accrued and unpaid interest
(including Additional Amounts, if any), as of the Conversion Date ("PRINCIPAL
VALUE CONVERSION"). Any Common Stock delivered upon a Principal Value Conversion
will be valued at the greater of the Conversion Price on the Conversion Date and
the average of the Last Reported Sale Price of the Common Stock for a five (5)
Trading Day period starting the third Trading Day following the Conversion Date
of such Debentures. If a holder of Debentures surrenders their Debentures for a
Principal Value Conversion, the Company shall notify such holder by the second
Trading Day following the Conversion Date that it is a Principal Value
Conversion and whether the Company will pay such Holder all or a portion of the
principal amount plus accrued and unpaid interest and Additional Amounts, if
any, in cash, Common Stock or a combination of cash and Common Stock, and in
what percentage. The Company will pay such holder any portion of the principal
amount plus accrued and unpaid interest and Additional Amounts, if any, to be
paid in cash and deliver Common Stock with respect to any portion of the
principal amount plus accrued and unpaid interest and Additional Amounts, if
any, to be paid in Common Stock, no later than the third Business Day following
the determination of the average Last Reported Sale Price of the Common Stock.

         The Company or its designated agent shall determine on a daily basis
during the time period specified in Section 15.01(a)(i) whether the Debentures
shall be convertible as a result of the occurrence of an event specified in
clause (i) above and, if the Debentures shall be so convertible, the Company
shall promptly deliver to the Trustee (or other Conversion Agent appointed by
the Company) written notice thereof. Whenever the Debentures shall become
convertible pursuant to this Section 15.01, the Company or, at the Company's
request, the Trustee in the name and at the expense of the Company, shall notify
the holders of the event triggering such convertibility in the manner provided
in Section 16.04, and the Company shall also publicly announce such information
by publication on the Company's web site or through

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such other public medium as it may use at such time. Any notice so given shall
be conclusively presumed to have been duly given, whether or not the holder
receives such notice.

         The Trustee (or other Conversion Agent appointed by the Company) shall
have no obligation to determine the Trading Price under this Section 15.01
unless the Company has requested in writing such a determination; and the
Company shall have no obligation to make such request unless a holder provides
it with reasonable evidence that the Trading Price per $1,000 principal amount
of Debentures would be less than 98% of the product of the Last Reported Sale
Price of the Common Stock and the Conversion Rate. If such evidence is provided,
the Company shall instruct the Trustee (or other Conversion Agent) in writing to
determine the Trading Price of the Debentures beginning on the next Trading Day
and on each successive Trading Day until, and only until, the Trading Price per
$1,000 principal amount of Debentures is greater than or equal to 98% of the
product of the Last Reported Sale Price of the Common Stock and the Conversion
Rate.

         The Trustee shall be entitled at its sole discretion to consult with
the Company and to request the assistance of the Company in connection with the
Trustee's duties and obligations pursuant to Section 15.01(a) hereof, and the
Company agrees, if requested by the Trustee, to cooperate with, and provide
assistance to, the Trustee in carrying out its duties under this Section 15.01;
provided, however, that nothing herein shall be construed to relieve the Trustee
of its duties pursuant to Section 15.01(a) hereof.

         (b)      In addition, if:

                  (i)      the Company distributes to all holders of its Common
         Stock rights or warrants entitling them (for a period expiring within
         forty-five (45) days of the date of the distribution) to subscribe for
         or purchase shares of Common Stock at a price per share less than the
         Last Reported Sale Price of the Common Stock on the Trading Day
         immediately preceding the declaration date of the distribution, or (B)
         the Company distributes to all holders of Common Stock assets
         (including cash), debt securities or rights to purchase securities of
         the Company, which distribution has a per share value as determined by
         the Company's Board of Directors and set forth in a Board Resolution
         exceeding 10% of the Last Reported Sale Price of the Common Stock on
         the Trading Day immediately preceding the declaration date for such
         distribution, then, in either case, the Debentures may be surrendered
         for conversion at any time on and after the date that the Company gives
         notice to the holders of such distribution, which shall be not less
         than twenty (20) days prior to the Ex-Dividend Date for such
         distribution, until the earlier of the close of business on the
         Business Day immediately preceding, but not including, the Ex-Dividend
         Date or the date the Company publicly announces that such distribution
         will not take place; provided that no adjustment to the Conversion
         Price or the ability of a holder of a Debenture to convert will be made
         if the holder will otherwise participate in such distribution without
         conversion; and

                  (ii)     the Company consolidates with or merges with or into
         another Person or is a party to a binding share exchange or conveys,
         transfers, sells, leases or otherwise disposes of all or substantially
         all of its properties and assets, in each case pursuant to which the
         Common Stock is converted into cash or property other than securities,
         then

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<PAGE>

         the Debentures may be surrendered for conversion at any time from and
         after the date fifteen (15) days prior to the anticipated effective
         date of the transaction and ending on and including the date fifteen
         (15) days after the anticipated effective date of the transaction.

The Board of Directors shall determine the anticipated effective date of the
transaction, and such determination shall be conclusive and binding on the
holders and shall be publicly announced by the Company by publication on its web
site or through such other public medium as it may use at that time not later
than two (2) Business Days prior to such fifteenth day.

         (c)      A Debenture in respect of which a holder is electing to
exercise its option to require repurchase upon a Fundamental Change pursuant to
Section 3.05 or repurchase pursuant to Section 3.06 may be converted only if
such holder withdraws its election in accordance with Section 3.08(d). A holder
of Debentures is not entitled to any rights of a holder of Common Stock until
such holder has converted his Debentures to Common Stock, and only to the extent
such Debentures are deemed to have been converted to Common Stock under this
Article 15.

         Section 15.02. Exercise of Conversion Privilege; Issuance of Common
Stock on Conversion; No Adjustment for Interest or Dividends; Settlement of Cash
or Common Stock upon Conversion. (a) In order to exercise the conversion
privilege with respect to any Debenture in certificated form, the Company must
receive at the office or agency of the Company maintained for that purpose or,
at the option of such holder, the Corporate Trust Office, such Debenture with
the original or facsimile of the form entitled "FORM OF CONVERSION NOTICE" on
the reverse thereof, duly completed and manually signed, together with such
Debentures duly endorsed for transfer, accompanied by the funds, if any,
required by Section 15.02(d). Such notice shall also state the name or names
(with address or addresses) in which the certificate or certificates for shares
of Common Stock which shall be issuable on such conversion shall be issued, and
shall be accompanied by transfer or similar taxes, if required pursuant to
Section 15.07.

         In order to exercise the conversion privilege with respect to any
interest in a Global Debenture, the beneficial holder must complete, or cause to
be completed, the appropriate instruction form for conversion pursuant to the
Depositary's book-entry conversion program, deliver, or cause to be delivered,
by book-entry delivery an interest in such Global Debenture, furnish appropriate
endorsements and transfer documents if required by the Company or the Trustee or
Conversion Agent, and pay the funds, if any, required by this Section 15.02 and
any transfer taxes if required pursuant to Section 15.07.

         (b)      As promptly as practicable after satisfaction of the
requirements for conversion set forth above, subject to compliance with any
restrictions on transfer if shares issuable on conversion are to be issued in a
name other than that of the Debentureholder (as if such transfer were a transfer
of the Debenture or Debentures (or portion thereof) so converted), the Company
shall issue and shall deliver to such Debentureholder at the office or agency
maintained by the Company for such purpose pursuant to Section 5.02, a
certificate or certificates for the number of full shares of Common Stock
issuable upon the conversion of such Debenture or portion thereof as determined
by the Company in accordance with the provisions of this Article 15 and a check
or cash in respect of the Cash Amount pursuant to Section 15.02(h)(iii) (if
applicable) and any

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fractional interest in respect of a share of Common Stock arising upon such
conversion, calculated by the Company as provided in Section 15.03. In case any
Debenture of a denomination greater than $1,000 shall be surrendered for partial
conversion, subject to Section 2.03, the Company shall execute and the Trustee
shall authenticate and deliver to the holder of the Debenture so surrendered,
without charge to him, a new Debenture or Debentures in authorized denominations
in an aggregate principal amount equal to the unconverted portion of the
surrendered Debenture.

         (c)      Each conversion shall be deemed to have been effected as to
any such Debenture (or portion thereof) on the date on which the requirements
set forth above in this Section 15.02 have been satisfied as to such Debenture
(or portion thereof) (such date, the "CONVERSION DATE"), and the Person in whose
name any certificate or certificates for shares of Common Stock shall be
issuable upon such conversion shall be deemed to have become on said date the
holder of record of the shares represented thereby; provided that any such
surrender on any date when the stock transfer books of the Company shall be
closed shall constitute the Person in whose name the certificates are to be
issued as the record holder thereof for all purposes on the next succeeding day
on which such stock transfer books are open, but such conversion shall be at the
Conversion Rate in effect on the date upon which such Debenture shall be
surrendered.

         (d)      Any Debenture or portion thereof surrendered for conversion
during the period from the close of business on any Regular Record Date to the
close of business on the Business Day preceding the following Interest Payment
Date that has not been called for redemption during such period shall be
accompanied by payment, in immediately available funds or other funds acceptable
to the Company, of an amount equal to the interest otherwise payable on such
Interest Payment Date on the principal amount being converted; provided that no
such payment need be made (1) if the Company has specified a Redemption Date
that is after a Regular Record Date and prior to the next Interest Payment Date,
(2) if the Company has specified a Repurchase Date following a Fundamental
Change that is during such period or (3) to the extent of any overdue interest,
if any overdue interest exists at the time of conversion with respect to such
Debenture. Except as provided above in this Section 15.02, no payment or other
adjustment shall be made for interest accrued on any Debenture converted or for
dividends on any shares issued upon the conversion of such Debenture as provided
in this Article 15.

         (e)      Upon the conversion of an interest in a Global Debenture, the
Trustee (or other Conversion Agent appointed by the Company), or the Custodian
at the direction of the Trustee (or other Conversion Agent appointed by the
Company), shall make a notation on such Global Debenture as to the reduction in
the principal amount represented thereby. The Company shall notify the Trustee
in writing of any conversions of Debentures effected through any Conversion
Agent other than the Trustee.

         (f)      Upon the conversion of a Debenture, that portion of the
accrued but unpaid interest with respect to the converted Debenture shall not be
canceled, extinguished or forfeited, but rather shall be deemed to be paid in
full to the holder thereof through delivery of the Common Stock (together with
the cash payment, if any, in lieu of fractional shares) or cash or a combination
of cash and shares of Common Stock in exchange for the Debenture being converted
pursuant to the provisions hereof; and the fair market value of such shares of
Common Stock and any such cash payment in lieu of fractional shares shall be
treated as issued or paid, as

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the case may be, to the extent thereof, first in exchange for and in
satisfaction of the Company's obligation to pay the principal amount of the
converted Debenture and the accrued but unpaid interest, and the balance, if
any, of such fair market value of such Common Stock and any such cash payment
shall be treated as issued or paid, as the case may be, in exchange for and in
satisfaction of the right to convert the Debenture being converted pursuant to
the provisions hereof.

         (g)      In the event that the Company receives a Form of Conversion
Notice on or prior to (1) the date on which the Company gives a Redemption
Notice or (2) the date that is 20 days prior to the Stated Maturity of the
Debentures (the "FINAL NOTICE DATE"), the following procedures shall apply:

                  (i)      If the Company elects to satisfy all or any portion
         of its obligation to convert the Debentures (the "CONVERSION
         Obligation") in cash, the Company shall notify holders through the
         Trustee of the dollar amount to be satisfied in cash (which must be
         expressed either as 100% of the Conversion Obligation or as a fixed
         dollar amount) at any time on or before the date that is two Business
         Days following the Conversion Date (the "CASH SETTLEMENT NOTICE
         PERIOD"). If the Company timely elects to pay cash for any portion of
         the Common Stock otherwise issuable to holders upon conversion, holders
         may retract the Conversion Notice at any time during the two Business
         Days following the final day of the Cash Settlement Notice Period (the
         "CONVERSION RETRACTION PERIOD"). No such retraction can be made (and a
         Form of Conversion Notice shall be irrevocable) if the Company does not
         elect to deliver cash in lieu of Common Stock (other than cash in lieu
         of fractional shares). Upon the expiration of a Conversion Retraction
         Period, a Form of Conversion Notice shall be irrevocable. If the
         Company elects to satisfy all or any portion of the Conversion
         Obligation in cash, and the applicable Form of Conversion Notice has
         not been retracted, then settlement (in cash or in cash and Common
         Stock) will occur on the Business Day following the final day of the
         20-Trading Day period beginning on the day after the final day of the
         Conversion Retraction Period (the "CASH SETTLEMENT AVERAGING PERIOD").

                  (ii)     If the Company does not elect to satisfy any part of
         the Conversion Obligation in cash (other than cash in lieu of any
         fractional shares), delivery of the Common Stock into which the
         Debentures are converted (and cash in lieu of any fractional shares)
         shall occur through the Conversion Agent or the Depositary, as the case
         may be, as soon as practicable on or after the Conversion Date.

         (h)      Settlement amounts will be computed as follows:

                  (i)      If the Company elects to satisfy the entire
         Conversion Obligation in Common Stock, it shall deliver to holders that
         have delivered the Conversion Notice giving rise to the Conversion
         Obligation a number of shares of Common Stock equal to (i) the
         aggregate principal amount of Debentures to be converted divided by
         1,000, multiplied by (ii) the Conversion Rate. In addition, the Company
         shall pay cash for any fractional shares of Common Stock based on the
         Last Reported Sale Price of the Common Stock on the Trading Day
         immediately preceding the Conversion Date.

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                  (ii)     If the Company elects to satisfy the entire
         Conversion Obligation in cash, it shall deliver to holders that have
         delivered the Conversion Notice giving rise to the Conversion
         Obligation cash in an amount equal to the product of:

                           (A)      a number equal to (i) the aggregate
                  principal amount of Debentures to be converted divided by
                  1,000, multiplied by (ii) the Conversion Rate; and

                           (B)      the average Last Reported Sale Price of the
                  Common Stock during the Cash Settlement Averaging Period.

                  (iii)    If the Company elects to satisfy a fixed portion
         (other than 100%) of the Conversion Obligation in cash, it will deliver
         to holders the specified cash amount (the "CASH AMOUNT") and a number
         of shares of Common Stock equal to the greater of (i) zero and (ii) the
         excess, if any, of the number of shares of Common Stock calculated as
         if the Company elected to satisfy the entire Conversion Obligation in
         shares over the number of shares equal to the sum, for each day of the
         Cash Settlement Averaging Period, of (x) the Cash Amount divided by the
         number of days in the Cash Settlement Averaging Period, divided by (y)
         the Last Reported Sale Price of the Common Stock. In addition, the
         Company shall pay cash for all fractional Common Stock based on the
         average Last Reported Sale Price of the Common Stock during the Cash
         Settlement Averaging Period.

                  (iv)     If the Company elects to satisfy the Conversion
         Obligation in Common Stock and if on the date of the Conversion Notice
         (x) the Debentures are neither registered under the Securities Act nor
         immediately freely saleable pursuant to Rule 144(k) under the
         Securities Act and (y) there exists a Registration Default (as defined
         under the Registration Right Agreement), then the Company shall deliver
         to Debentureholders an additional number of shares of Common Stock in
         accordance with Section 3(a) of the Registration Rights Agreement.

         (i)      The Company must determine whether or not it will satisfy all
or a portion of the Conversion Obligation in cash at the time it issues a
Redemption Notice and such notice will state the amount of the Conversion
Obligation to be settled in cash (which must be expressed either as 100% of the
Conversion Obligation or a fixed dollar amount). If the Company elects to
satisfy all or any portion of the Conversion Obligation with respect to
conversions after the Final Notice Date in cash, on or before the Final Notice
Date the Company will send a single notice to holders indicating the dollar
amount to be satisfied in cash (which must be expressed either as 100% of the
Conversion Obligation or a fixed dollar amount). In the event that the Company
receives a Form of Conversion Notice after the date a Redemption Notice has been
issued or the Final Notice Date, settlement amounts will be computed and
settlement dates will be determined in the same manner as set forth in clauses
(g) and (h) of this Section 15.02 except that the Cash Settlement Averaging
Period shall be the 20 Trading Day period beginning on the Trading Day after the
Conversion Date. If a Form of Conversion Notice is received from holders of
Debentures after the date that a Redemption Notice has been issued or the Final
Notice Date, such holders may not retract their Conversion Notice. Settlement
(in cash and/or Common Stock) will occur on the Business Day following the final
day of such Cash Settlement Averaging Period.

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         Section 15.03. Cash Payments in Lieu of Fractional Shares. No
fractional shares of Common Stock or scrip certificates representing fractional
shares shall be issued upon conversion of Debentures. If more than one Debenture
shall be surrendered for conversion at one time by the same holder, the number
of full shares that shall be issuable upon conversion shall be computed on the
basis of the aggregate principal amount of the Debentures (or specified portions
thereof to the extent permitted hereby) so surrendered. If any fractional share
of stock would be issuable upon the conversion of any Debenture or Debentures,
the Company shall make an adjustment and payment therefor in cash to the holder
of Debentures at the Last Reported Sale Price of the Common Stock on the last
Trading Day immediately preceding the day on which the Debentures (or specified
portions thereof) are deemed to have been converted.

         Section 15.04. Conversion Rate. Each $1,000 principal amount of the
Debentures shall be convertible into the number of shares of Common Stock
specified in the form of Debenture (herein called the "CONVERSION RATE")
attached as Exhibit A hereto (initially 89.7989 shares), subject to adjustment
as provided in this Article 15.

         Section 15.05. Adjustment of Conversion Rate. The Conversion Rate shall
be adjusted from time to time by the Company as follows:

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

                  (i)      the numerator of which shall be the sum of the number
         of shares of Common Stock outstanding at the close of business on the
         date fixed for the determination of stockholders entitled to receive
         such dividend or other distribution plus the total number of shares of
         Common Stock constituting such dividend or other distribution, and

                  (ii)     the denominator of which shall be the number of
         shares of Common Stock outstanding at the close of business on the date
         fixed for such determination,

such increase to become effective immediately after the opening of business on
the Business Day following the date fixed for such determination. If any
dividend or distribution of the type described in this Section 15.05(a) is
declared but not so paid or made, the Conversion Rate shall again be adjusted to
the Conversion Rate that would then be in effect if such dividend or
distribution had not been declared.

         (b)      In case the Company shall (other than pursuant to a dividend
reinvestment plan or share purchase plan) issue rights, options or warrants to
all holders of its Common Stock entitling them, for a period expiring within
forty-five (45) days after the date fixed for the determination of stockholders
entitled to receive such rights, options or warrants, to subscribe for or
purchase shares of Common Stock at a price per share less than the Current
Market Price per share of the Common Stock on the date fixed for the
determination of stockholders entitled to receive such rights, options or
warrants, the Conversion Rate in effect at the opening of business

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on the day following the date fixed for such determination shall be increased by
multiplying such Conversion Rate by a fraction,

                  (i)      the numerator of which shall be the number of shares
         of Common Stock outstanding at the close of business on the date fixed
         for such determination plus the number of shares of Common Stock so
         offered for subscription or purchase at such below Current Market
         Price, and

                  (ii)     the denominator of which shall be the number of
         shares of Common Stock outstanding at the close of business on the date
         fixed for such determination plus the number of shares of Common Stock
         that the aggregate offering price of the total number of shares of
         Common Stock so offered for subscription or purchase would purchase at
         such Current Market Price,

such adjustment shall be successively made whenever any such rights or warrants
are issued and shall become effective immediately after the opening of business
on the Business Day following the date fixed for such determination. The Company
shall not issue any such rights, options or warrants in respect of shares of
Common Stock held in treasury by the Company. To the extent that shares of
Common Stock are not delivered after the expiration of such rights or warrants,
the Conversion Rate shall be readjusted to the Conversion Rate that would then
be in effect had the adjustments made upon the issuance of such rights or
warrants been made on the basis of delivery of only the number of shares of
Common Stock actually delivered. If such rights or warrants are not so issued,
the Conversion Rate shall again be adjusted to be the Conversion Rate that would
then be in effect if such date fixed for the determination of stockholders
entitled to receive such rights or warrants had not been fixed.

         In determining whether any rights or warrants entitle the holders to
subscribe for or purchase shares of Common Stock at less than such Current
Market Price, and in determining the aggregate offering price of such shares of
Common Stock, there shall be taken into account any consideration received by
the Company for such rights or warrants and any amount payable on exercise or
conversion thereof, the value of such consideration, if other than cash, to be
determined by the Board of Directors.

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

         (d)      In case the Company shall, by dividend or otherwise,
distribute to all holders of its Common Stock evidences of its indebtedness,
shares of capital stock, securities, cash or other property (but excluding any
dividend or distribution referred to in Section 15.05(a), any rights, options or
warrants referred to in Section 15.05(b) and any dividend or distribution paid

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exclusively in cash referred to in Section 15.05(e)), the Conversion Rate shall
be adjusted by multiplying the Conversion Rate in effect immediately prior to
the close of business on the date fixed for the determination of stockholders
entitled to receive such distribution by a fraction,

                  (i)      the numerator of which shall be the Current Market
         Price per share of the Common Stock on the date fixed for such
         determination, and

                  (ii)     the denominator of which shall be the Current Market
         Price per share of the Common Stock on such date less the then Fair
         Market Value (as determined by the Board of Directors, whose
         determination shall be conclusive and described in a Board Resolution)
         on such date of the portion of the evidences of indebtedness, shares of
         capital stock, securities, cash or other property so distributed
         applicable to one share of Common Stock,

such adjustment to become effective immediately prior to the opening of business
on the Business Day following the date fixed for the determination of
stockholders entitled to receive such distribution; provided, however, that in
the event that the Company makes a distribution to all holders of its Common
Stock consisting of capital stock of, or similar equity interests in, a
subsidiary or other business unit of the Company, the Conversion Rate shall be
adjusted by multiplying the Conversion Rate in effect immediately prior to the
close of business on the date fixed for the determination of stockholders
entitled to receive such distribution by a fraction of which the numerator shall
be the Spin-off Market Price per share of the Common Stock plus the Spin-off
Market Price per share or similar equity interest of the subsidiary or other
business unit of the Company on such date and the denominator shall be the
Spin-off Market Price per share of the Common Stock on the date fixed for such
determination, such adjustment to become effective ten (10) consecutive Trading
Days after the effective date of such distribution of capital stock of, or
similar equity interest in, a subsidiary or other business unit of the Company.
In any case in which this Section 15.05(d) is applicable, Section 15.05(a) and
(b) shall not be applicable. If such dividend or distribution is not so paid or
made, the Conversion Rate shall again be adjusted to be the Conversion Rate that
would then be in effect if such dividend or distribution had not been declared.

         (e)      In case the Company shall, by dividend or otherwise,
distribute to all holders of its Common Stock distributions consisting
exclusively of cash (excluding (i) any dividend or distribution in connection
with the liquidation, dissolution or winding up of the Company, whether
voluntary or involuntary and (ii) any dividend or distribution paid after
October 1, 2008 to the extent that the aggregate amount of such payment per
share of Common Stock in any twelve month period does not exceed 5% of the
arithmetic average of the Last Reported Sale Price of the Common Stock during
the ten (10) consecutive Trading Days immediately prior to the date of the
declaration of the dividend or distribution), then, immediately after the close
of business on such date for determination, 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 the close of business on the date
fixed for determination of the stockholders entitled to receive such
distribution by a fraction:

                  (i)      the numerator of which shall be equal to the Current
         Market Price per share of the Common Stock on such date fixed for
         determination; and

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                  (ii)     the denominator of which shall be equal to the
         Current Market Price per share of the Common Stock on such date fixed
         for such determination less the amount of such distribution of cash
         applicable to one share of Common Stock that exceeds the amount of
         dividends and distributions permitted to be excluded pursuant to this
         Section 15.05(e).

         (f)      In case a tender or exchange offer made by the Company or any
subsidiary of the Company for all or any portion of the Common Stock shall
expire and such tender or exchange offer (as amended upon the expiration
thereof) shall require the payment to stockholders of consideration per share of
Common Stock having a Fair Market Value (as determined by the Board of
Directors, whose determination shall be conclusive and described in a resolution
of the Board of Directors) that as of the last time (the "EXPIRATION TIME")
tenders or exchanges may be made pursuant to such tender or exchange offer (as
it may be amended) exceeds the Last Reported Sale Price of a share of Common
Stock on the Trading Day next succeeding the Expiration Time, 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 the Expiration
Time by a fraction:

                  (i)      the numerator of which shall be the sum of (x) the
         Fair Market Value (determined as aforesaid) of the aggregate
         consideration payable to stockholders based on the acceptance (up to
         any maximum specified in the terms of the tender or exchange offer) of
         all shares validly tendered or exchanged and not withdrawn as of the
         Expiration Time (the shares deemed so accepted up to any such maximum,
         being referred to as the "PURCHASED SHARES") and (y) the product of the
         number of shares of Common Stock outstanding (less any Purchased
         Shares) at the Expiration Time and the Last Reported Sale Price of a
         share of Common Stock on the Trading Day next succeeding the Expiration
         Time, and

                  (ii)     the denominator of which shall be the number of
         shares of Common Stock outstanding (including any tendered or exchanged
         shares) at the Expiration Time multiplied by the Last Reported Sale
         Price of a share of Common Stock on the Trading Day next succeeding the
         Expiration Time,

such adjustment to become effective immediately prior to the opening of business
on the day following the Expiration Time. If the Company is obligated to
purchase shares pursuant to any such tender or exchange offer, but the Company
is permanently prevented by applicable law from effecting any such purchases or
all such purchases are rescinded, the Conversion Rate shall again be adjusted to
be the Conversion Rate that would then be in effect if such tender or exchange
offer had not been made.

         (g)      The reclassification of Common Stock into securities other
than Common Stock (other than any reclassification upon an event to which
Section 15.06 applies) shall be deemed to involve (a) a distribution of such
securities other than Common Stock to all holders of Common Stock (and the
effective date of such reclassification shall be deemed to be "THE DATE FIXED
FOR THE DETERMINATION OF STOCKHOLDERS ENTITLED TO RECEIVE SUCH DISTRIBUTION" and
the "DATE FIXED FOR SUCH DETERMINATION" within the meaning of Section 15.05(d)),
and (b) a subdivision, split or combination, as the case may be, of the number
of shares of Common Stock outstanding

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immediately prior to such reclassification into the number of shares of Common
Stock outstanding immediately thereafter (and the effective date of such
reclassification shall be deemed to be "THE DAY UPON WHICH SUCH SUBDIVISION OR
SPLIT BECOMES EFFECTIVE" or "THE DAY UPON WHICH SUCH COMBINATION BECOMES
EFFECTIVE," as the case may be, and "THE DAY UPON WHICH SUCH SUBDIVISION, SPLIT
OR COMBINATION BECOMES EFFECTIVE" within the meaning of Section 15.05(c)).

         (h)      Notwithstanding the foregoing provisions of Section 15.05, no
adjustment shall be made thereunder, nor shall an adjustment be made to the
ability of a holder of a Debenture to convert, for any distribution described
therein if the holder will otherwise participate in the distribution without
conversion of such holder's Debentures.

         (i)      The Company may make such increases in the Conversion Rate, in
addition to those required by clauses (a) through (g) of this Section 15.05 as
the Board of Directors considers to be advisable to avoid or diminish any income
tax to holders of Common Stock or rights to purchase Common Stock resulting from
any dividend or distribution of stock (or rights to acquire stock) or from any
event treated as such for income tax purposes.

         To the extent permitted by applicable law, the Company from time to
time may increase the Conversion Rate by any amount for any period of time if
the period is at least twenty (20) days, the increase is irrevocable during the
period and the Board of Directors shall have made a determination that such
increase would be in the best interests of the Company, which determination
shall be conclusive. Whenever the Conversion Rate is increased pursuant to the
preceding sentence, the Company shall mail to holders of record of the
Debentures a notice of the increase at least fifteen (15) days prior to the date
the increased Conversion Rate takes effect, and such notice shall state the
increased Conversion Rate and the period during which it will be in effect.

         (j)      No adjustment to the Conversion Rate need be made:

                  (i)      upon the issuance of any shares of Common Stock
         pursuant to any present or future plan providing for the reinvestment
         of dividends or interest payable on securities of the Company and the
         investment of additional optional amounts in shares of Common Stock
         under any plan;

                  (ii)     upon the issuance of any shares of Common Stock or
         options or rights to purchase those shares pursuant to any present or
         future employee, director or consultant benefit plan or program of or
         assumed by the Company or any of its subsidiaries;

                  (iii)    upon the issuance of any shares of Common Stock
         pursuant to any option, warrant, right, or exercisable, exchangeable or
         convertible security not described in (ii) above and outstanding as of
         the Original Issuance Date;

                  (iv)     for a change in the par value of the Common Stock; or

                  (v)      for accrued and unpaid interest, if any.

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         (k)      No adjustment in the Conversion Rate shall be required unless
such adjustment would require an increase or decrease of at least 1% in such
rate; provided that any adjustments that by reason of this Section 15.05(k) are
not required to be made shall be carried forward and taken into account in any
subsequent adjustment. All calculations under this Article 15 shall be made by
the Company and shall be made to the nearest cent or to the nearest one-ten
thousandth (1/10,000) of a share, as the case may be.

         (l)      Whenever the Conversion Rate is adjusted as herein provided,
the Company shall promptly file with the Trustee and any Conversion Agent other
than the Trustee an Officers' Certificate setting forth the Conversion Rate
after such adjustment and setting forth a brief statement of the facts requiring
such adjustment. Unless and until a Responsible Officer of the Trustee shall
have received such Officers' Certificate, the Trustee shall not be deemed to
have knowledge of any adjustment of the Conversion Rate and may assume that the
last Conversion Rate of which it has knowledge is still in effect. Promptly
after delivery of such certificate, the Company shall prepare a notice of such
adjustment of the Conversion Rate setting forth the adjusted Conversion Rate and
the date on which each adjustment becomes effective and shall mail such notice
of such adjustment of the Conversion Rate to the holder of each Debenture at its
last address appearing on the Debenture Register provided for in Section 2.05 of
this Indenture, within twenty (20) days after execution thereof. Failure to
deliver such notice shall not affect the legality or validity of any such
adjustment.

         (m)      In any case in which this Section 15.05 provides that an
adjustment shall become effective immediately after (1) a record date or Stock
Record Date for an event, (2) the date fixed for the determination of
stockholders entitled to receive a dividend or distribution pursuant to Section
15.05(a), (3) a date fixed for the determination of stockholders entitled to
receive rights or warrants pursuant to Section 15.05(b) or (4) the Expiration
Time for any tender or exchange offer pursuant to Section 15.05(f), (each a
"DETERMINATION DATE"), the Company may elect to defer until the occurrence of
the applicable Adjustment Event (as hereinafter defined) (x) issuing to the
holder of any Debenture converted after such Determination Date and before the
occurrence of such Adjustment Event, the additional shares of Common Stock or
other securities issuable upon such conversion by reason of the adjustment
required by such Adjustment Event over and above the Common Stock issuable upon
such conversion before giving effect to such adjustment and (y) paying to such
holder any amount in cash in lieu of any fraction pursuant to Section 15.03;
provided that in the case of an adjustment made pursuant to Section 15.05(d)
with respect to a distribution of shares of capital stock of, or similar equity
interest in, a subsidiary or other business unit of the Company, the Company may
defer the issuance of such additional shares and cash payment, if any, until the
third Business Day immediately following the last day of the 20 consecutive
Trading Day period commencing on the fifth Trading Day after the Ex-Dividend
Date. For purposes of this Section 15.05(m), the term "ADJUSTMENT EVENT" shall
mean:

                  (i)      in any case referred to in clause (1) hereof, the
         occurrence of such event;

                  (ii)     in any case referred to in clause (2) hereof, the
         date any such dividend or distribution is paid or made;

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                  (iii)    in any case referred to in clause (3) hereof, the
         date of expiration of such rights or warrants; and

                  (iv)     in any case referred to in clause (4) hereof, the
         date a sale or exchange of Common Stock pursuant to such tender or
         exchange offer is consummated and becomes irrevocable.

         (n)      For purposes of this Section 15.05, the number of shares of
Common Stock at any time outstanding shall not include shares held in the
treasury of the Company but shall include shares issuable in respect of scrip
certificates issued in lieu of fractions of shares of Common Stock. The Company
will not pay any dividend or make any distribution on shares of Common Stock
held in the treasury of the Company.

         Section 15.06. Effect of Reclassification, Consolidation, Merger or
Sale. If any of the following events occur, namely (i) any reclassification or
change of the outstanding shares of Common Stock (other than a subdivision or
combination to which Section 15.05(c) applies), (ii) any consolidation, merger
or combination of the Company with another Person as a result of which holders
of Common Stock shall be entitled to receive stock, other securities or other
property or assets (including cash) with respect to or in exchange for such
Common Stock, or (iii) any sale or conveyance of all or substantially all of the
properties and assets of the Company to any other Person as a result of which
holders of Common Stock shall be entitled to receive stock, other securities or
other property or assets (including cash) with respect to or in exchange for
such Common Stock, then the Company or the successor or purchasing Person, as
the case may be, shall execute with the Trustee a supplemental indenture (which
shall comply with the Trust Indenture Act as in force at the date of execution
of such supplemental indenture) providing that each Debenture shall be
convertible into the kind and amount of shares of stock, other securities or
other property or assets (including cash) receivable upon such reclassification,
change, consolidation, merger, combination, sale or conveyance by a holder of a
number of shares of Common Stock issuable upon conversion of such Debentures
(assuming, for such purposes, a sufficient number of authorized shares of Common
Stock are available to convert all such Debentures) immediately prior to such
reclassification, change, consolidation, merger, combination, sale or conveyance
assuming such holder of Common Stock did not exercise his rights of election, if
any, as to the kind or amount of stock, other securities or other property or
assets (including cash) receivable upon such reclassification, change,
consolidation, merger, combination, sale or conveyance (provided that, if the
kind or amount of stock, other securities or other property or assets (including
cash) receivable upon such reclassification, change, consolidation, merger,
combination, sale or conveyance is not the same for each share of Common Stock
in respect of which such rights of election shall not have been exercised
("NON-ELECTING SHARE"), then for the purposes of this Section 15.06 the kind and
amount of stock, other securities or other property or assets (including cash)
receivable upon such reclassification, change, consolidation, merger,
combination, sale or conveyance for each non-electing share shall be deemed to
be the kind and amount so receivable per share by a plurality of the
non-electing shares). Such supplemental indenture shall provide for adjustments
which shall be as nearly equivalent as may be practicable to the adjustments
provided for in this Article 15.

         The Company shall cause notice of the execution of such supplemental
indenture to be mailed to each holder of Debentures, at its address appearing on
the Debenture Register provided

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for in Section 2.05 of this Indenture, within twenty (20) days after execution
thereof. Failure to deliver such notice shall not affect the legality or
validity of such supplemental indenture.

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

         If this Section 15.06 applies to any event or occurrence, Section 15.05
shall not apply.

         Section 15.07. Taxes on Shares Issued. The issue of stock certificates
on conversions of Debentures shall be made without charge to the converting
Debentureholder for any documentary, stamp or similar issue or transfer tax in
respect of the issue thereof. The Company shall not, however, be required to pay
any such tax which may be payable in respect of any transfer involved in the
issue and delivery of stock in any name other than that of the holder of any
Debenture converted, and the Company shall not be required to issue or deliver
any such stock certificate unless and until the Person or Persons requesting the
issue thereof shall have paid to the Company the amount of such tax or shall
have established to the satisfaction of the Company that such tax has been paid.

         Section 15.08. Reservation of Shares, Shares to Be Fully Paid;
Compliance with Governmental Requirements; Listing of Common Stock. The Company
shall provide, free from preemptive rights, out of its authorized but unissued
shares or shares held in treasury, sufficient shares of Common Stock to provide
for the conversion of the Debentures from time to time as such Debentures are
presented for conversion.

         Before taking any action which would cause an adjustment increasing the
Conversion Rate to an amount that would cause the Conversion Price to be reduced
below the then par value, if any, of the shares of Common Stock issuable upon
conversion of the Debentures, the Company will take all corporate action which
may, in the opinion of its counsel, be necessary in order that the Company may
validly and legally issue shares of such Common Stock at such adjusted
Conversion Rate.

         The Company covenants that all shares of Common Stock which may be
issued upon conversion of Debentures will upon issue be fully paid and
nonassessable by the Company and free from all taxes, Liens and charges with
respect to the issue thereof.

         The Company covenants that, if any shares of Common Stock to be
provided for the purpose of conversion of Debentures hereunder require
registration with or approval of any governmental authority under any federal or
state law before such shares may be validly issued upon conversion, the Company
will in good faith and as expeditiously as possible, to the extent then
permitted by the rules and interpretations of the Commission (or any successor
thereto), endeavor to secure such registration or approval, as the case may be.

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

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<PAGE>

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

         Section 15.09. Responsibility of Trustee. The Trustee and any other
Conversion Agent shall not at any time be under any duty or responsibility to
any holder of Debentures to determine the Conversion Rate or whether any facts
exist which may require any adjustment of the Conversion Rate, or with respect
to the nature or extent or calculation of any such adjustment when made, or with
respect to the method employed, or herein or in any supplemental indenture
provided to be employed, in making the same. The Trustee and any other
Conversion Agent shall not be accountable with respect to the validity or value
(or the kind or amount) of any shares of Common Stock, or of any securities or
property, which may at any time be issued or delivered upon the conversion of
any Debenture; and the Trustee and any other Conversion Agent make no
representations with respect thereto. Neither the Trustee nor any Conversion
Agent shall be responsible for any failure of the Company to issue, transfer or
deliver any shares of Common Stock or stock certificates or other securities or
property or cash upon the surrender of any Debenture for the purpose of
conversion or to comply with any of the duties, responsibilities or covenants of
the Company contained in this Article 15. Without limiting the generality of the
foregoing, neither the Trustee nor any Conversion Agent shall be under any
responsibility to determine the correctness of any provisions contained in any
supplemental indenture entered into pursuant to Section 15.06 relating either to
the kind or amount of shares of stock or securities or property (including cash)
receivable by Debentureholders upon the conversion of their Debentures after any
event referred to in such Section 15.06 or to any adjustment to be made with
respect thereto, but, subject to the provisions of Section 8.01, may accept as
conclusive evidence of the correctness of any such provisions, and shall be
protected in relying upon, the Officers' Certificate (which the Company shall be
obligated to file with the Trustee prior to the execution of any such
supplemental indenture) with respect thereto.

         Section 15.10. Notice to Holders Prior to Certain Actions. In case:

                  (a)      the Company shall declare a dividend (or any other
         distribution) on its Common Stock that would require an adjustment in
         the Conversion Rate pursuant to Section 15.05; or

                  (b)      the Company shall authorize the granting to the
         holders of all or substantially all of its Common Stock of rights or
         warrants to subscribe for or purchase any share of any class or any
         other rights or warrants; or

                  (c)      of any reclassification or reorganization of the
         Common Stock of the Company (other than a subdivision or combination of
         its outstanding Common Stock, or a change in par value, or from par
         value to no par value, or from no par value to par value), or of any
         consolidation or merger to which the Company is a party and for which
         approval of any stockholders of the Company is required, or of the sale
         or transfer of all or substantially all of the assets of the Company;
         or

                                       85

<PAGE>

                  (d)      of the voluntary or involuntary dissolution,
         liquidation or winding up of the Company;

the Company shall cause to be filed with the Trustee and to be mailed to each
holder of Debentures at its address appearing on the Debenture Register provided
for in Section 2.05 of this Indenture, as promptly as possible but in any event
at least ten (10) days prior to the applicable date hereinafter specified, a
notice stating (x) the date on which a record is to be taken for the purpose of
such dividend, distribution or rights or warrants, or, if a record is not to be
taken, the date as of which the holders of Common Stock of record to be entitled
to such dividend, distribution or rights are to be determined, or (y) the date
on which such reclassification, consolidation, merger, sale, transfer,
dissolution, liquidation or winding up is expected to become effective or occur,
and the date as of which it is expected that holders of Common Stock of record
shall be entitled to exchange their Common Stock for securities or other
property deliverable upon such reclassification, consolidation, merger, sale,
transfer, dissolution, liquidation or winding up. Failure to give such notice,
or any defect therein, shall not affect the legality or validity of such
dividend, distribution, reclassification, consolidation, merger, sale, transfer,
dissolution, liquidation or winding up.

         Section 15.11. Stockholder Rights Plans. If the rights provided for in
the existing rights plan adopted by the Company have separated from the shares
of Common Stock in accordance with the provisions of the applicable stockholder
rights agreement so that the holders of the Debentures would not be entitled to
receive any rights in respect of Common Stock issuable upon conversion of the
Debentures, the conversion rate will be adjusted as if the Company distributed
to all holders of Common Stock shares of the Company's capital stock, evidences
of indebtedness or assets (including securities but excluding rights or warrants
to purchase Common Stock issued to all holders of Common Stock, Common Stock
issued as a dividend or distribution on Common Stock and cash distributions),
subject to readjustment in the event of the expiration, termination or
redemption of the rights. In lieu of any such adjustment, the Company may amend
such applicable stockholder rights agreement to provide that upon conversion of
the Debentures the holders will receive, in addition to the Common Stock
issuable upon such conversion, the rights which would have attached to such
Common Stock if the rights had not become separated from the Common Stock under
such applicable stockholder rights agreement. To the extent that the Company
adopts any future rights plan, upon conversion of the Debentures into Common
Stock, holders of Debentures shall receive, in addition to Common Stock, the
rights under the future rights plan whether or not the rights have separated
from the Common Stock at the time of conversion and no adjustment will be made
in accordance with Section 15.05(d).

                                   ARTICLE 16
                            MISCELLANEOUS PROVISIONS

         Section 16.01. Confidentiality Exception. Notwithstanding any other
provision of this Indenture, each Debentureholder (and each employee,
representative or other agent of such Debentureholder) may disclose to any and
all persons, without limitation of any kind, the tax treatment and tax structure
(as such terms are used in Sections 6011, 6111 and 6112 of the Code and the
Treasury Regulations promulgated thereunder) of the Debentures and all materials
of any kind (including opinions or other tax analyses) that are provided
relating to such tax treatment

                                       86

<PAGE>

and tax structure, other than any information for which nondisclosure is
reasonably necessary in order to comply with applicable securities laws, and the
ability of the Company, its subsidiaries and their respective representatives,
affiliates, employees, officers, directors or other agents to consult any tax
advisor, including an independent tax advisor, regarding the tax treatment or
tax structure of the Debentures (and any transactions related thereto) shall not
be restricted in any manner.

         Section 16.02. Provisions Binding on Company's Successors. All the
covenants, stipulations, promises and agreements by the Company contained in
this Indenture shall bind its successors and assigns whether so expressed or
not.

         Section 16.03. Official Acts by Successor Corporation. Any act or
proceeding by any provision of this Indenture authorized or required to be done
or performed by any board, committee or officer of the Company shall and may be
done and performed with like force and effect by the like board, committee or
officer of any Person that shall at the time be the lawful sole successor of the
Company.

         Section 16.04. Addresses for Notices, Etc. Any notice or demand which
by any provision of this Indenture is required or permitted to be given or
served by the Trustee or by the holders of Debentures on the Company shall be
deemed to have been sufficiently given or made, for all purposes, if given or
served by being deposited postage prepaid by registered or certified mail in a
post office letter box or sent by telecopier transmission addressed as follows:
Quanta Services, Inc., 1360 Post Oak Boulevard, Suite 2100, Houston, TX 77056,
Attention: Chief Financial Officer. Any notice, direction, request or demand
hereunder to or upon the Trustee shall be deemed to have been sufficiently given
or made, for all purposes, if given or served by being deposited, postage
prepaid, by registered or certified mail in a post office letter box or sent by
telecopier transmission addressed to the Corporate Trust Office of the Trustee.

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

         Any notice or communication mailed to a Debentureholder shall be mailed
to him by first class mail, postage prepaid, at his address as it appears on the
Debenture Register and shall be sufficiently given to him if so mailed within
the time prescribed.

         Failure to mail a notice or communication to a Debentureholder or any
defect in it shall not affect its sufficiency with respect to other
Debentureholders. If a notice or communication is mailed in the manner provided
above, it is duly given, whether or not the addressee receives it.

         Section 16.05. Governing Law. This Indenture and each Debenture shall
be deemed to be a contract made under the laws of the State of New York, and for
all purposes shall be construed in accordance with the laws of the State of New
York (including Section 5-1401 of the New York General Obligations Law or any
successor to such statute).

         Section 16.06. Evidence of Compliance with Conditions Precedent,
Certificates to Trustee. Upon any application or demand by the Company to the
Trustee to take any action under any of the provisions of this Indenture, the
Company shall furnish to the Trustee an Officers' Certificate stating that all
conditions precedent, if any, provided for in this Indenture

                                       87

<PAGE>

relating to the proposed action have been complied with, and an Opinion of
Counsel stating that, in the opinion of such counsel, all such conditions
precedent have been complied with.

         Each certificate or opinion provided for in this Indenture and
delivered to the Trustee with respect to compliance with a condition or covenant
provided for in this Indenture shall include: (1) a statement that each Person
making such certificate or opinion has read such covenant or condition; (2) a
brief statement as to the nature and scope of the examination or investigation
upon which the statement or opinion contained in such certificate or opinion is
based; (3) a statement that, in the opinion of each such Person, he has made
such examination or investigation as is necessary to enable him to express an
informed opinion as to whether or not such covenant or condition has been
complied with; and (4) a statement as to whether or not, in the opinion of each
such Person, such condition or covenant has been complied with.

         Section 16.07. Legal Holidays. In any case in which the date of
maturity of interest on or principal of the Debentures or the Redemption Date of
any Debenture or any Repurchase Date with respect to any Debenture will not be a
Business Day, then payment of such interest on or principal of the Debentures
need not be made on such date, but may be made on the next succeeding Business
Day with the same force and effect as if made on the date of maturity or the
Redemption Date or the Repurchase Date, as the case may be, and no interest
shall accrue for the period from and after such date.

         Section 16.08. Company Responsible for Making Calculations. Unless
otherwise specified in this Indenture, the Company will be responsible for
making all calculations called for under the Debentures. These calculations
include, but are not limited to, determination of the Current Market Price, Last
Reported Sale Price, Market Price and Spin-off Market Price, the amount of
accrued interest payable on the Debentures and the Conversion Rate of the
Debentures. The Company will make these calculations in good faith and, absent
manifest error, these calculations will be final and binding on the
Debentureholders. Promptly after the calculation thereof, the Company will
provide to each of the Trustee and the Conversion Agent an Officers' Certificate
setting forth a schedule of its calculations, and each of the Trustee and the
Conversion Agent is entitled to conclusively rely upon the accuracy of such
calculations without independent verification. The Trustee will forward the
Company's calculations to any holder upon the request of such holder.

         Section 16.09. Trust Indenture Act. This Indenture is hereby made
subject to, and shall be governed by, the provisions of the Trust Indenture Act
required to be part of and to govern indentures qualified under the Trust
Indenture Act; provided that unless otherwise required by law, notwithstanding
the foregoing, this Indenture and the Debentures issued hereunder shall not be
subject to the provisions of subsections (a)(1), (a)(2), and (a)(3) of Section
314 of the Trust Indenture Act as now in effect or as hereafter amended or
modified; provided further that this Section 16.09 shall not require this
Indenture or the Trustee to be qualified under the Trust Indenture Act prior to
the time such qualification is in fact required under the terms of the Trust
Indenture Act, nor shall it constitute any admission or acknowledgment by any
party to the Indenture that any such qualification is required prior to the time
such qualification is in fact required under the terms of the Trust Indenture
Act. If any provision hereof limits, qualifies or conflicts with another
provision hereof which is required to be included in an indenture qualified
under the Trust Indenture Act, such required provision shall control.

                                       88

<PAGE>

         Section 16.10. No Security Interest Created. Except as provided in
Section 8.06, nothing in this Indenture or in the Debentures, expressed or
implied, shall be construed to constitute a security interest under the Uniform
Commercial Code or similar legislation, as now or hereafter enacted and in
effect, in any jurisdiction in which property of the Company or its subsidiaries
is located.

         Section 16.11. Benefits of Indenture. Nothing in this Indenture or in
the Debentures, express or implied, shall give to any Person, other than the
parties hereto, any Paying Agent, any authenticating agent, any Debenture
Registrar and their successors hereunder and the holders of Debentures any
benefit or any legal or equitable right, remedy or claim under this Indenture.

         Section 16.12. Table of Contents, Headings, Etc. The table of contents
and the titles and headings of the Articles and Sections of this Indenture have
been inserted for convenience of reference only, are not to be considered a part
hereof, and shall in no way modify or restrict any of the terms or provisions
hereof.

         Section 16.13. Authenticating Agent. The Trustee may appoint an
authenticating agent that shall be authorized to act on its behalf, and subject
to its direction, in the authentication and delivery of Debentures in connection
with the original issuance thereof and transfers and exchanges of Debentures
hereunder, including under Sections 2.04, 2.05, 2.06, 2.07, 3.02 and 3.08, as
fully to all intents and purposes as though the authenticating agent had been
expressly authorized by this Indenture and those Sections to authenticate and
deliver Debentures. For all purposes of this Indenture, the authentication and
delivery of Debentures by the authenticating agent shall be deemed to be
authentication and delivery of such Debentures "by the Trustee" and a
certificate of authentication executed on behalf of the Trustee by an
authenticating agent shall be deemed to satisfy any requirement hereunder or in
the Debentures for the Trustee's certificate of authentication. Such
authenticating agent shall at all times be a Person eligible to serve as trustee
hereunder pursuant to Section 8.09.

         Any corporation into which any authenticating agent may be merged or
converted or with which it may be consolidated, or any corporation resulting
from any merger, consolidation or conversion to which any authenticating agent
shall be a party, or any corporation succeeding to the corporate trust business
of any authenticating agent, shall be the successor of the authenticating agent
hereunder, if such successor corporation is otherwise eligible under this
Section 16.13, without the execution or filing of any paper or any further act
on the part of the parties hereto or the authenticating agent or such successor
corporation.

         Any authenticating agent may at any time resign by giving written
notice of resignation to the Trustee and to the Company. The Trustee may at any
time terminate the agency of any authenticating agent by giving written notice
of termination to such authenticating agent and to the Company. Upon receiving
such a notice of resignation or upon such a termination, or in case at any time
any authenticating agent shall cease to be eligible under this Section, the
Trustee shall either promptly appoint a successor authenticating agent or itself
assume the duties and obligations of the former authenticating agent under this
Indenture and, upon such appointment of a successor authenticating agent, if
made, shall give written notice of such appointment of a successor
authenticating agent to the Company and shall mail notice of such appointment of
a

                                       89

<PAGE>

successor authenticating agent to all holders of Debentures as the names and
addresses of such holders appear on the Debenture Register.

         The Company agrees to pay to the authenticating agent from time to time
such reasonable compensation for its services as shall be agreed upon in writing
between the Company and the authenticating agent.

         The provisions of Sections 8.02, 8.03, 8.04 and 9.03 and this Section
16.13 shall be applicable to any authenticating agent.

         Section 16.14. Execution in Counterparts. This Indenture may be
executed in any number of counterparts, each of which shall be an original, but
such counterparts shall together constitute but one and the same instrument.

         Section 16.15. Severability. In case any provision in this Indenture or
in the Debentures shall be invalid, illegal or unenforceable, then (to the
extent permitted by law) the validity, legality and enforceability of the
remaining provisions shall not in any way be affected or impaired thereby.

         Wells Fargo Bank, N.A. hereby accepts the trusts in this Indenture
declared and provided, upon the terms and conditions herein above set forth.

            [THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK]

                                       90

<PAGE>

         IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be
duly executed.

                                  QUANTA SERVICES, INC.

                                  By: /s/ DANA A. GORDON
                                      ------------------------------------------
                                      Name: Dana A. Gordon
                                      Title: Vice President, General Counsel and
                                             Secretary

                                  WELLS FARGO BANK, N.A., as Trustee

                                  By: /s/ MELISSA SCOTT
                                      ------------------------------------------
                                      Name: Melissa Scott
                                      Title: Vice President

                                       91

<PAGE>

                                                                       EXHIBIT A

[Include only for Global Debentures:]

[UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE
DEPOSITORY TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK) (THE
"DEPOSITARY", WHICH TERM INCLUDES ANY SUCCESSOR DEPOSITORY FOR THE CERTIFICATES)
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 REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITARY (AND
ANY PAYMENT HEREIN IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED
BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITARY), ANY TRANSFER, PLEDGE, OR
OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH
AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.]

[Include only for Debentures that are Restricted Securities:]

[THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED (THE "SECURITIES ACT"), OR THE SECURITIES LAWS OF ANY STATE OR OTHER
JURISDICTION. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY
BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE
DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS
EXEMPT FROM, OR NOT SUBJECT TO, SUCH REGISTRATION. THE HOLDER OF THIS SECURITY,
BY ITS ACCEPTANCE HEREOF, (1) REPRESENTS THAT IT IS A "QUALIFIED INSTITUTIONAL
BUYER" (AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT ("RULE 144A")); (2)
AGREES ON ITS OWN BEHALF AND ON BEHALF OF ANY INVESTOR ACCOUNT FOR WHICH IT HAS
PURCHASED SECURITIES, TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY OR ANY
COMMON STOCK ISSUABLE UPON CONVERSION OF SUCH SECURITY, PRIOR TO THE EXPIRATION
OF THE HOLDING PERIOD APPLICABLE TO SALES OF THIS SECURITY UNDER RULE 144 UNDER
THE SECURITIES ACT (OR ANY SUCCESSOR PROVISION) ONLY (A) TO THE ISSUER, (B)
PURSUANT TO A REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER THE
SECURITIES ACT (AND WHICH CONTINUES TO BE EFFECTIVE AT THE TIME OF SUCH
TRANSFER), (C) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO
RULE 144A, IN COMPLIANCE WITH RULE 144A TO A PERSON IT REASONABLY BELIEVES IS A
QUALIFIED INSTITUTIONAL BUYER THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE
ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE
TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A OR (D) PURSUANT TO ANOTHER
AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT;
SUBJECT TO THE ISSUER'S AND THE TRUSTEE'S RIGHT PRIOR TO ANY SUCH OFFER, SALE OR
TRANSFER PURSUANT TO CLAUSE (D) TO REQUIRE THE DELIVERY OF AN OPINION OF
COUNSEL, CERTIFICATION AND/OR

<PAGE>

OTHER INFORMATION SATISFACTORY TO EACH OF THEM; AND (3) AGREES THAT IT WILL
DELIVER TO EACH PERSON TO WHOM THIS SECURITY IS TRANSFERRED A NOTICE
SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. THIS LEGEND WILL BE REMOVED UPON THE
TRANSFER OF THIS SECURITY PURSUANT TO CLAUSE 2(B) ABOVE OR UNDER RULE 144 UNDER
THE SECURITIES ACT (OR ANY SUCCESSOR PROVISION).]

THE HOLDER OF THIS SECURITY IS ENTITLED TO THE BENEFITS OF A REGISTRATION RIGHTS
AGREEMENT DATED AS OF OCTOBER 17, 2003 AND, BY ITS ACCEPTANCE HEREOF, AGREES TO
BE BOUND BY AND TO COMPLY WITH THE PROVISIONS OF SUCH REGISTRATION RIGHTS
AGREEMENT.

                                      A-2

<PAGE>

                              QUANTA SERVICES, INC.

                4.50% CONVERTIBLE SUBORDINATED DEBENTURE DUE 2023

                                                              CUSIP: 74762E AB 8
                                                              ISIN: US74762EAB83

No. 1                                                               $225,000,000

         Quanta Services, Inc., a corporation duly organized and validly
existing under the laws of the State of Delaware (herein called the "COMPANY",
which term includes any successor corporation under the Indenture referred to on
the reverse hereof), for value received, hereby promises to pay to CEDE & CO. or
its registered assigns [the principal sum of TWO HUNDRED AND TWENTY-FIVE MILLION
DOLLARS] [the principal sum set forth on Schedule I hereto]1 on October 1, 2023
at the office or agency of the Company maintained for that purpose in accordance
with the terms of the Indenture, in such coin or currency of the United States
of America as at the time of payment shall be legal tender for the payment of
public and private debts, and to pay interest, semiannually on April 1 and
October 1 of each year, commencing April 1, 2004, on said principal sum at said
office or agency, in like coin or currency, at the rate per annum of 4.50% from
the later of October 17, 2003 or the most recent date to which interest has been
duly paid or provided for until payment of said principal sum has been made or
duly provided for; provided that if the Company shall default in the payment of
interest due on such April 1 or October 1, then this Debenture shall bear
interest from the next preceding April 1 or October 1 to which interest has been
paid or duly provided for; and provided further that if no interest has been
paid or duly provided for on this Debenture, then this Debenture shall bear
interest from October 17, 2003. Except as otherwise provided in the Indenture,
the interest payable on the Debenture pursuant to the Indenture on any April 1
or October 1 will be paid to the Person entitled thereto as it appears in the
Debenture Register at the close of business on the Regular Record Date, which
shall be the March 15 or September 15 (whether or not a Business Day) next
preceding such April 1 or October 1, as provided in the Indenture; provided that
any such interest not punctually paid or duly provided for shall be payable as
provided in the Indenture. The Company shall pay interest (i) on any Debentures
in certificated form by check mailed to the address of the Person entitled
thereto as it appears in the Debenture Register (or, upon written notice, by
wire transfer in immediately available funds, if such Person is entitled to
interest on Debentures with an aggregate principal amount in excess of
$2,000,000) or (ii) on any Global Debenture by wire transfer of immediately
available funds to the account of the Depositary or its nominee.

         The Company promises to pay interest on overdue principal and (to the
extent that payment of such interest is enforceable under applicable law)
interest at the rate of 4.50% per annum, compounded semiannually.

         Reference is made to the further provisions of this Debenture set forth
on the reverse hereof, including, without limitation, provisions giving the
holder of this Debenture the right to convert this Debenture into Common Stock
of the Company on the terms and subject to the

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

(1) For Global Debentures only.

                                      A-3

<PAGE>

limitations referred to on the reverse hereof and as more fully specified in the
Indenture. Under the circumstances described in the Indenture, the Company may
fulfill all or part of its conversion obligation by delivering cash in lieu of
Common Stock.

         This Debenture shall be deemed to be a contract made under the laws of
the State of New York, and for all purposes shall be construed in accordance
with and governed by the laws of the State of New York (including Section 5-1401
of the New York General Obligations Law or any successor to such statute).

         This Debenture shall not be valid or become obligatory for any purpose
until the certificate of authentication hereon shall have been manually signed
by the Trustee or a duly authorized authenticating agent under the Indenture.

                                      A-4

<PAGE>

         IN WITNESS WHEREOF, the Company has caused this Debenture to be duly
executed.

                                 QUANTA SERVICES, INC.

                                 By: ___________________________________________
                                     Dana A. Gordon
                                     Vice President, General Counsel & Secretary

October 17, 2003

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

This is one of the Debentures described in the within-named Indenture.

WELLS FARGO BANK, N.A.,
     as Trustee

By: ____________________________________
    Authorized Signatory

                                , or

By: ____________________________________
    As Authenticating Agent
    (if different from Trustee)

         By: ____________________________
             Authorized Signatory

                                      A-5

<PAGE>

                          FORM OF REVERSE OF DEBENTURE

                              QUANTA SERVICES, INC.

                4.50% CONVERTIBLE SUBORDINATED DEBENTURE DUE 2023

         This Debenture is one of a duly authorized issue of Debentures of the
Company, designated as its 4.50% Convertible Subordinated Debentures due 2023
(herein called the "DEBENTURES"), limited in aggregate principal amount to
$270,000,000, issued and to be issued under and pursuant to an Indenture dated
as of October 17, 2003 (herein called the "INDENTURE"), between the Company and
Wells Fargo Bank, N.A., as trustee (herein called the "TRUSTEE"), to which
Indenture and all indentures supplemental thereto reference is hereby made for a
description of the rights, limitations of rights, obligations, duties and
immunities thereunder of the Trustee, the Company and the holders of the
Debentures.

         In case an Event of Default shall have occurred and be continuing, the
principal of and accrued interest on all Debentures may be declared by either
the Trustee or the holders of not less than 25% in aggregate principal amount of
the Debentures then outstanding, and upon said declaration shall become, due and
payable, in the manner, with the effect and subject to the conditions provided
in the Indenture.

         The Indenture contains provisions permitting the Company and the
Trustee, with the consent of the holders of at least a majority in aggregate
principal amount of the Debentures at the time outstanding, to execute
supplemental indentures adding any provisions to or changing in any manner or
eliminating any of the provisions of the Indenture or of any supplemental
indenture or modifying in any manner the rights of the holders of the
Debentures; provided that no such supplemental indenture shall (i) extend the
Stated Maturity of any Debenture, or reduce the rate or extend the time of
payment of interest thereon, or reduce the principal amount thereof or reduce
any amount payable upon redemption or repurchase thereof, or impair the right of
any Debentureholder to institute suit for the payment thereof, or make the
principal thereof or interest thereon payable in any coin or currency other than
that provided in the Debentures, or change the obligation of the Company to
redeem any Debenture on a Redemption Date in a manner adverse to the holder of
the Debentures, or change the obligation of the Company to repurchase any
Debenture upon a Fundamental Change in a manner adverse to the holder of the
Debentures, or change the obligation of the Company to repurchase any Debenture
on a Company Repurchase Date in a manner adverse to the holder of the
Debentures, or impair the right to convert the Debentures into Common Stock
subject to the terms set forth in the Indenture, including Section 15.06
thereof, or reduce the number of shares of Common Stock or other property
receivable upon conversion, in each case without the consent of the holder of
each Debenture so affected, or modify any of the provisions of Section 11.02 or
Section 7.07 thereof, except to increase any such percentage or to provide that
certain other provisions of the Indenture cannot be modified or waived without
the consent of the holder of each Debenture so affected, or change any
obligation of the Company to maintain an office or agency in the places and for
the purposes set forth in Section 5.02 thereof, or reduce the quorum or voting
requirements set forth in Article 10 or (ii) reduce the aforesaid percentage of
Debentures, the holders of which are required to consent to any such
supplemental indenture, without the consent of the holders of all Debentures
then outstanding. Subject to the provisions of the Indenture, the holders of a

                                      A-6

<PAGE>

majority in aggregate principal amount of the Debentures at the time outstanding
may on behalf of the holders of all of the Debentures waive any past default or
Event of Default under the Indenture and its consequences except (A) a default
in the payment of interest on or the principal of any of the Debentures, (B) a
failure by the Company to convert any Debentures into Common Stock, (C) a
default in the payment of the Redemption Price pursuant to Article 3 of the
Indenture, (D) a default in the payment of the Company Repurchase Price or
Fundamental Change Repurchase Price pursuant to Article 3 of the Indenture or
(E) a default in respect of a covenant or provisions of the Indenture which
under Article 11 of the Indenture cannot be modified or amended without the
consent of the holders of each or all Debentures then outstanding or affected
thereby. Any such consent or waiver by the holder of this Debenture (unless
revoked as provided in the Indenture) shall be conclusive and binding upon such
holder and upon all future holders and owners of this Debenture and any
Debentures which may be issued in exchange or substitution hereof, irrespective
of whether or not any notation thereof is made upon this Debenture or such other
Debentures.

         No reference herein to the Indenture and no provision of this Debenture
or of the Indenture shall alter or impair the obligation of the Company, which
is absolute and unconditional, to pay the principal of and interest on this
Debenture at the place, at the respective times, at the rate and in the coin or
currency herein prescribed.

         Interest on the Debentures shall be computed on the basis of a 360-day
year of twelve 30-day months.

         The Debentures are issuable in fully registered form, without coupons,
in denominations of $1,000 principal amount and any multiple of $1,000. At the
office or agency of the Company referred to on the face hereof, and in the
manner and subject to the limitations provided in the Indenture, without payment
of any service charge but with payment of a sum sufficient to cover any tax,
assessment or other governmental charge that may be imposed in connection with
any registration or exchange of Debentures, Debentures may be exchanged for a
like aggregate principal amount of Debentures of any other authorized
denominations.

         At any time on or after October 8, 2008 and prior to maturity, the
Debentures may be redeemed at the option of the Company, in whole or in part, in
cash upon mailing a notice of such redemption not less than thirty (30) days but
not more than sixty (60) days before the Redemption Date to the holders of
Debentures at their last registered addresses, all as provided in the Indenture,
at a Redemption Price equal to 100% of the principal amount of Debentures being
redeemed plus accrued and unpaid interest to, but excluding, the Redemption
Date; provided that if the Redemption Date is on April 1 or October 1, then the
interest payable on such date shall be paid to the holder of record on the
preceding March 15 or September 15, respectively.

         In no event will any Debenture be redeemable at the option of the
Company before October 8, 2008.

         The Company may not give notice of any redemption of the Debentures if
a default in the payment of interest on the Debentures has occurred and is
continuing.

         The Debentures are not subject to redemption through the operation of
any sinking fund.

                                      A-7

<PAGE>

         If a Fundamental Change occurs at any time prior to maturity of the
Debentures, this Debenture will be redeemable on a Fundamental Change Repurchase
Date, specified by the Company, which shall be no later than thirty-five (35)
Business Days after the occurrence of such Fundamental Change, at the option of
the holder of this Debenture at a Fundamental Change Repurchase Price equal to
100% of the principal amount thereof, together with accrued interest to (but
excluding) the Fundamental Change Repurchase Date; provided that if such
Fundamental Change Repurchase Date falls after a record date and on or prior to
the corresponding Interest Payment Date, the interest payable on such Interest
Payment Date shall be paid to the holder of record of this Debenture on the
preceding March 15 or September 15, respectively. The Debentures will be
redeemable in multiples of $1,000 principal amount. The Company shall mail to
all holders of record of the Debentures a notice of the occurrence of a
Fundamental Change and of the repurchase right arising as a result thereof on or
before the twenty-fifth (25th) Business Day prior to each Fundamental Change
Repurchase Date. For a Debenture to be so repurchased at the option of the
holder, the Company must receive at the office or agency of the Company
maintained for that purpose in accordance with the terms of the Indenture, such
Debenture with the form entitled "FORM OF FUNDAMENTAL CHANGE REPURCHASE
ELECTION" on the reverse hereof duly completed, together with such Debenture,
duly endorsed for transfer, on or before the close of business on the Business
Day immediately preceding the Fundamental Change Repurchase Date.

         Subject to the terms and conditions of the Indenture, the Company shall
become obligated to repurchase, at the option of the holder, all or any portion
of the Debentures held by such holder on October 1, 2008, October 1, 2013, and
October 1, 2018 in integral multiples of $1,000 at a Company Repurchase Price of
100% of the principal amount, plus any accrued and unpaid interest on such
Debenture to but excluding the Company Repurchase Date. To exercise such right,
a holder shall deliver to the Company such Debenture with the form entitled
"FORM OF COMPANY REPURCHASE ELECTION" on the reverse hereof duly completed,
together with the Debenture, duly endorsed for transfer, at any time from the
opening of business on the date that is twenty (20) Business Days prior to such
Company Repurchase Date until the close of business on the Business Day
immediately preceding the Company Repurchase Date, and shall deliver the
Debentures to the Trustee (or other Paying Agent appointed by the Company) as
set forth in the Indenture.

         The Company Repurchase Price with respect to the Company Repurchase
Date occurring on October 1, 2008 shall be paid only in cash. The Company
Repurchase Price to be paid on any of October 1, 2013 or October 1, 2018 and the
Fundamental Change Repurchase Price to be paid on any Fundamental Change
Repurchase Date may be paid, at the option of the Company, in cash or by the
issuance and delivery of shares of Common Stock, or in any combination thereof,
subject to the terms and conditions of the Indenture.

         Holders have the right to withdraw any Repurchase Election by
delivering to the Trustee (or other Paying Agent appointed by the Company) a
written notice of withdrawal up to the close of business on the Business Day
immediately preceding the Repurchase Date, all as provided in the Indenture.

         If cash or securities sufficient to pay the Repurchase Price with
respect to all Debentures or portions thereof to be repurchased as of any
Repurchase Date are deposited with the Trustee

                                      A-8

<PAGE>

(or other Paying Agent appointed by the Company), then on and after such
Repurchase Date, interest will cease to accrue on such Debentures (or portions
thereof), and the holder thereof shall have no other rights as such other than
the right to receive the Repurchase Price upon surrender of such Debenture.

         Subject to the occurrence of certain events and in compliance with the
provisions of the Indenture, prior to the Stated Maturity of the Debentures, the
holder hereof has the right, at its option, to convert each $1,000 principal
amount of the Debentures into 89.7989 shares of the Company's Common Stock (at a
Conversion Price of approximately $11.14 per share), as such shares shall be
constituted at the date of conversion and subject to adjustment from time to
time as provided in the Indenture, upon surrender of this Debenture with the
form entitled "FORM OF CONVERSION NOTICE" on the reverse hereof duly completed,
to the Company at the office or agency of the Company maintained for that
purpose in accordance with the terms of the Indenture or, at the option of such
holder, the Corporate Trust Office, and, unless the shares issuable on
conversion are to be issued in the same name as this Debenture, duly endorsed
by, or accompanied by instruments of transfer in form satisfactory to the
Company duly executed by, the holder or by his duly authorized attorney. The
Company will notify the holder thereof of any event triggering the right to
convert the Debentures as specified above in accordance with the Indenture.

         If the Company (i) is a party to a consolidation, merger, statutory
share exchange or combination, (ii) reclassifies the Common Stock or (iii) sells
or conveys its properties and assets substantially as an entirety to any Person,
the right to convert a Debenture into shares of Common Stock may be changed into
a right to convert it into securities, cash or other assets of the Company or
such other Person, in each case in accordance with the Indenture.

         No adjustment in respect of interest on any Debenture converted or
dividends on any shares issued upon conversion of such Debenture will be made
upon any conversion except as set forth in the next sentence. If this Debenture
(or portion hereof) is surrendered for conversion during the period from the
close of business on any record date for the payment of interest to the close of
business on the Business Day preceding the following Interest Payment Date and
has not been called for redemption by the Company on a Redemption Date that
occurs during such period, this Debenture (or portion hereof being converted)
must be accompanied by payment, in immediately available funds or other funds
acceptable to the Company, of an amount equal to the interest otherwise payable
on such Interest Payment Date on the principal amount being converted; provided
that no such payment shall be required (1) if the Company has specified a
Redemption Date that is after a record date and prior to the next Interest
Payment Date, (2) if the Company has specified a Repurchase Date following a
Fundamental Change that is during such period or (3) to the extent of any
overdue interest, if any overdue interest exists at the time of conversion with
respect to such Debenture.

         No fractional shares will be issued upon any conversion, but an
adjustment and payment in cash will be made, as provided in the Indenture, in
respect of any fraction of a share which would otherwise be issuable upon the
surrender of any Debenture or Debentures for conversion.

                                      A-9

<PAGE>

         A Debenture in respect of which a holder is exercising its right to
require repurchase upon a Fundamental Change or repurchase on a Repurchase Date
may be converted only if such holder withdraws its election to exercise such
right in accordance with the terms of the Indenture.

         Any Debentures called for redemption, unless surrendered for conversion
by the holders thereof on or before the close of business on the second Business
Day preceding the Redemption Date, may be deemed to be redeemed from the holders
of such Debentures for an amount equal to the applicable Redemption Price,
together with accrued but unpaid interest to, but excluding, the Redemption
Date, by one or more investment banks or other purchasers who may agree with the
Company (i) to purchase such Debentures from the holders thereof and convert
them into shares of the Company's Common Stock and (ii) to make payment for such
Debentures as aforesaid to the Trustee in trust for the holders.

         Upon due presentment for registration of transfer of this Debenture at
the office or agency of the Company maintained for that purpose in accordance
with the terms of the Indenture, a new Debenture or Debentures of authorized
denominations for an equal aggregate principal amount will be issued to the
transferee in exchange thereof, subject to the limitations provided in the
Indenture, without charge except for any tax, assessment or other governmental
charge imposed in connection therewith.

         The Company, the Trustee, any authenticating agent, any Paying Agent,
any Conversion Agent and any Debenture Registrar may deem and treat the
registered holder hereof as the absolute owner of this Debenture (whether or not
this Debenture shall be overdue and notwithstanding any notation of ownership or
other writing hereon made by anyone other than the Company or any Debenture
Registrar) for the purpose of receiving payment hereof, or on account hereof,
for the conversion hereof and for all other purposes, and neither the Company
nor the Trustee nor any other authenticating agent nor any Paying Agent nor
other Conversion Agent nor any Debenture Registrar shall be affected by any
notice to the contrary. All payments made to or upon the order of such
registered holder shall, to the extent of the sum or sums paid, satisfy and
discharge liability for monies payable on this Debenture.

         No recourse for the payment of the principal of or interest on this
Debenture, or for any claim based hereon or otherwise in respect hereof, and no
recourse under or upon any obligation, covenant or agreement of the Company in
the Indenture or any supplemental indenture or in any Debenture, or because of
the creation of any indebtedness represented thereby, shall be had against any
incorporator, stockholder, employee, agent, officer or director or subsidiary,
as such, past, present or future, of the Company or of any successor
corporation, either directly or through the Company or any successor
corporation, whether by virtue of any constitution, statute or rule of law or by
the enforcement of any assessment or penalty or otherwise, all such liability
being, by acceptance hereof and as part of the consideration for the issue
hereof, expressly waived and released.

         Terms used in this Debenture and defined in the Indenture are used
herein as therein defined.

                                      A-10

<PAGE>

                                  ABBREVIATIONS

         The following abbreviations, when used in the inscription of the face
of this Debenture, shall be construed as though they were written out in full
according to applicable laws or regulations.

<TABLE>
<S>               <C>                                                <C>
TEN COM -         as tenants in common                               UNIF GIFT MIN ACT -___ Custodian ___
TEN ENT -         as tenant by the entireties                                               (Cust)       (Minor)
JT TEN -          as joint tenants with right of survivorship        under Uniform Gifts to Minors Act
                  and not as tenants in common                       ___________________________
                                                                                  (State)
</TABLE>

         Additional abbreviations may also be used though not in the above list.

                                      A-11

<PAGE>

                                     FORM OF
                                CONVERSION NOTICE

TO:      QUANTA SERVICES, INC.
         WELLS FARGO BANK, N.A.

         The undersigned registered owner of this Debenture hereby irrevocably
exercises the option to convert this Debenture, or the portion thereof (which is
$1,000 or a multiple thereof) below designated, into shares of Common Stock of
Quanta Services, Inc. in accordance with the terms of the Indenture referred to
in this Debenture, and directs that the shares issuable and deliverable upon
such conversion, together with any check in payment for fractional shares and
any Debentures representing any unconverted principal amount hereof, be issued
and delivered to the registered holder hereof unless a different name has been
indicated below. Capitalized terms used herein but not defined shall have the
meanings ascribed to such terms in the Indenture. If shares or any portion of
this Debenture not converted are to be issued in the name of a person other than
the undersigned, the undersigned will provide the appropriate information below
and pay all transfer taxes payable with respect thereto. Any amount required to
be paid by the undersigned on account of interest and Additional Amounts, if
any, accompanies this Debenture.

Dated: _____________________________

                                                 _______________________________

                                                 _______________________________
                                                 Signature(s)

                                      A-12

<PAGE>

                                       Signature(s) must be guaranteed by an
                                       "ELIGIBLE GUARANTOR INSTITUTION" meeting
                                       the requirements of the Debenture
                                       Registrar, which requirements include
                                       membership or participation in the
                                       Security Transfer Agent Medallion Program
                                       ("STAMP") or such other "SIGNATURE
                                       GUARANTEE PROGRAM" as may be determined
                                       by the Debenture Registrar in addition
                                       to, or in substitution for, STAMP, all in
                                       accordance with the Securities Exchange
                                       Act of 1934, as amended.

                                       _________________________________________
                                       Signature Guarantee

         Fill in the registration of shares of Common Stock if to be issued, and
Debentures if to be delivered, other than to and in the name of the registered
holder:

______________________________
(Name)

______________________________
(Street Address)

______________________________
(City, State and Zip Code)

______________________________
Please print name and address

Principal amount to be converted
(if less than all):

$_____________________________

Social Security or Other Taxpayer
Identification Number:

______________________________

                                      A-13

<PAGE>

                                     FORM OF
                     FUNDAMENTAL CHANGE REPURCHASE ELECTION

TO:      QUANTA SERVICES, INC.
         WELLS FARGO BANK, N.A.

         The undersigned registered owner of this Debenture hereby irrevocably
acknowledges receipt of a notice from Quanta Services, Inc. (the "COMPANY") as
to the occurrence of a Fundamental Change with respect to the Company and
requests and instructs the Company to repurchase the entire principal amount of
this Debenture, or the portion thereof (which is $1,000 or a multiple thereof)
below designated, in accordance with the terms of the Indenture referred to in
this Debenture at the price of 100% of such entire principal amount or portion
thereof, together with accrued interest to, but excluding, the Fundamental
Change Repurchase Date, to the registered holder hereof. Capitalized terms used
herein but not defined shall have the meanings ascribed to such terms in the
Indenture.

         If the Company elects to pay the Fundamental Change Repurchase Price,
in whole or in part, in shares of Common Stock but such portion of the
Fundamental Change Repurchase Price shall ultimately be paid to such holder
entirely in cash because any of the conditions to payment of the Fundamental
Change Repurchase Price in shares of Common Stock is not satisfied prior to the
close of business on the Business Day immediately preceding the Fundamental
Change Repurchase Date, the undersigned registered owner elects:

         [ ]      to withdraw this Fundamental Change Repurchase Election as to
                  $__________ principal amount of the Debentures to which this
                  Fundamental Change Repurchase Election relates (Certificate
                  Numbers: ______________________________________________), or

         [ ]      to receive cash in respect of $_______________ principal
                  amount of the Debentures to which this Fundamental Change
                  Repurchase Election relates.

Dated: ________________________

                                                    ____________________________

                                                    ____________________________
                                                    Signature(s)

                                      A-14

<PAGE>

NOTICE: The above signatures of the holder(s) hereof must correspond with the
name as written upon the face of the Debenture in every particular without
alteration or enlargement or any change whatever.

Debenture Certificate Number (if applicable):

Principal amount to be repurchased (if less than all):

Social Security or Other Taxpayer Identification Number:

                                      A-15

<PAGE>

                                     FORM OF
                           COMPANY REPURCHASE ELECTION

TO:      QUANTA SERVICES, INC.
         WELLS FARGO BANK, N.A.

         The undersigned registered owner of this Debenture hereby irrevocably
acknowledges receipt of a notice from Quanta Services, Inc. (the "COMPANY")
regarding the right of holders to elect to require the Company to repurchase the
Debentures and requests and instructs the Company to repay the entire principal
amount of this Debenture, or the portion thereof (which is $1,000 or an integral
multiple thereof) below designated, in accordance with the terms of the
Indenture at the price of 100% of such entire principal amount or portion
thereof, together with accrued interest to, but excluding, the Company
Repurchase Date, to the registered holder hereof. Capitalized terms used herein
but not defined shall have the meanings ascribed to such terms in the Indenture.
The Debentures shall be repurchased by the Company as of the Company Repurchase
Date pursuant to the terms and conditions specified in the Indenture. If the
Company elects to pay the Company Repurchase Price, in whole or in part, in
shares of Common Stock but such portion of the Company Repurchase Price shall
ultimately be paid to such holder entirely in cash because any of the conditions
to payment of the Company Repurchase Price in shares of Common Stock is not
satisfied prior to the close of business on the Business Day immediately
preceding the Company Repurchase Date, the undersigned registered owner elects:

         [ ]      to withdraw this Company Repurchase Election as to $__________
                  principal amount of the Debentures to which this Company
                  Repurchase Election relates (Certificate Numbers:
                  ______________________________________________), or

         [ ]      to receive cash in respect of $_______________ principal
                  amount of the Debentures to which this Company Repurchase
                  Election relates.

Dated: ________________________

                                                    ____________________________

                                                    ____________________________
                                                    Signature(s)

                                      A-16

<PAGE>

NOTICE: The above signatures of the holder(s) hereof must correspond with the
name as written upon the face of the Debenture in every particular without
alteration or enlargement or any change whatever.

Debenture Certificate Number (if applicable):

_________________________________________________

Principal amount to be repurchased (if less than all):

_________________________________________________

Social Security or Other Taxpayer Identification Number:

_________________________________________________

                                      A-17

<PAGE>

                                   ASSIGNMENT

         For value received _____________________ hereby sell(s) assign(s) and
transfer(s) unto __________________________________________ (Please insert
social security or other Taxpayer Identification Number of assignee) the within
Debenture, and hereby irrevocably constitutes and appoints attorney to transfer
said Debenture on the books of the Company, with full power of substitution in
the premises.

         In connection with any transfer of the Debenture prior to the
expiration of the holding period applicable to sales thereof under Rule 144(k)
under the Securities Act (or any successor provision) (other than any transfer
pursuant to a registration statement that has been declared effective under the
Securities Act), the undersigned confirms that such Debenture is being
transferred:

         [ ]      To Quanta Services, Inc. or a subsidiary thereof; or

         [ ]      To a "QUALIFIED INSTITUTIONAL BUYER" in compliance with Rule
                  144A under the Securities Act of 1933, as amended; or

         [ ]      Pursuant to and in compliance with Rule 144 under the
                  Securities Act of 1933, as amended; or

         [ ]      Pursuant to a Registration Statement which has been declared
                  effective under the Securities Act of 1933, as amended, and
                  which continues to be effective at the time of transfer;

and unless the Debenture has been transferred to Quanta Services, Inc. or a
subsidiary thereof, the undersigned confirms that such Debenture is not being
transferred to an "affiliate" of the Company as defined in Rule 144 under the
Securities Act of 1933, as amended.

         Unless one of the boxes is checked, the Trustee will refuse to register
any of the Debentures evidenced by this certificate in the name of any person
other than the registered holder thereof.

Dated: _______________________

                                                      __________________________

                                                      __________________________
                                                      Signature(s)

                                      A-18

<PAGE>

                                       Signature(s) must be guaranteed by an
                                       "ELIGIBLE GUARANTOR INSTITUTION" meeting
                                       the requirements of the Debenture
                                       Registrar, which requirements include
                                       membership or participation in the
                                       Security Transfer Agent Medallion Program
                                       ("STAMP") or such other "SIGNATURE
                                       GUARANTEE PROGRAM" as may be determined
                                       by the Debenture Registrar in addition
                                       to, or in substitution for, STAMP, all in
                                       accordance with the Securities Exchange
                                       Act of 1934, as amended.

                                       _________________________________________
                                       Signature Guarantee

NOTICE: The signature on the Conversion Notice, the Fundamental Change
Repurchase Election, the Company Repurchase Election or the Assignment must
correspond with the name as written upon the face of the Debenture in every
particular without alteration or enlargement or any change whatsoever.

                                      A-19

<PAGE>

                                                                      Schedule I

                [Include Schedule I only for a Global Debenture]

                              QUANTA SERVICES, INC.
                4.50% Convertible Subordinated Debenture due 2023

No. 1

<TABLE>
<CAPTION>
                                                                             Authorized
                               Notation Explaining Principal Amount     Signature of Trustee
  Date     Principal Amount                Recorded                         or Custodian
---------  ----------------    ------------------------------------     --------------------
<S>        <C>                 <C>                                      <C>
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
_________  ________________    ____________________________________     ____________________
</TABLE>