<PAGE>   1
                                                                     Exhibit 4.1








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

                               EMCORE CORPORATION

                   5% CONVERTIBLE SUBORDINATED NOTES DUE 2006

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

                                    INDENTURE

                             Dated as of May 7, 2001

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

                            Wilmington Trust Company

                                     Trustee

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

<PAGE>   2



                                TABLE OF CONTENTS


<TABLE>
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                                                                                                                Page
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<S>                <C>                                                                                          <C>
                                                      ARTICLE 1.
                                            DEFINITIONS AND INCORPORATION
                                                     BY REFERENCE

   Section 1.01.   Definitions....................................................................................1
   Section 1.02.   Other Definitions..............................................................................7
   Section 1.03.   Incorporation by Reference of Trust Indenture Act..............................................7
   Section 1.04.   Rules of Construction..........................................................................8

                                                       ARTICLE 2.
                                                       THE NOTES

   Section 2.01.   Form and Dating................................................................................8
   Section 2.02.   Execution and Authentication...................................................................9
   Section 2.03.   Registrar, Paying Agent and Conversion Agent...................................................9
   Section 2.04.   Paying Agent to Hold Money in Trust...........................................................10
   Section 2.05.   Holder Lists..................................................................................10
   Section 2.06.   Transfer and Exchange.........................................................................10
   Section 2.07.   Replacement Notes.............................................................................11
   Section 2.08.   Outstanding Notes.............................................................................12
   Section 2.09.   Treasury Notes................................................................................12
   Section 2.10.   Temporary Notes...............................................................................12
   Section 2.11.   Cancellation..................................................................................12
   Section 2.12.   Additional Transfer and Exchange Requirements.................................................13
   Section 2.13.   CUSIP Numbers.................................................................................18
   Section 2.14.   Defaulted Interest............................................................................18

                                                       ARTICLE 3.
                                              REDEMPTION AND PREPAYMENT

   Section 3.01.   Notices to Trustee............................................................................18
   Section 3.02.   Selection of Notes to Be Redeemed.............................................................18
   Section 3.03.   Notice of Redemption..........................................................................19
   Section 3.04.   Effect of Notice of Redemption................................................................20
   Section 3.05.   Deposit of Redemption Price...................................................................20
   Section 3.06.   Notes Redeemed in Part........................................................................20
   Section 3.07.   Provisional and Optional Redemption...........................................................20
   Section 3.08.   Mandatory Redemption..........................................................................21

                                                      ARTICLE 4.
                                                      CONVERSION

   Section 4.01.   Conversion Privilege..........................................................................21
   Section 4.02.   Conversion Procedure..........................................................................22
   Section 4.03.   Fractional Shares.............................................................................23
   Section 4.04.   Taxes on Conversion...........................................................................23
   Section 4.05.   Company to Provide Stock......................................................................23
   Section 4.06.   Adjustment of Conversion Price................................................................24

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                                       i

<PAGE>   3

<TABLE>
<CAPTION>

<S>                <C>                                                                                          <C>
   Section 4.07.   No Adjustment.................................................................................27
   Section 4.08.   Other Adjustments.............................................................................27
   Section 4.09.   Adjustments for Tax Purposes..................................................................27
   Section 4.10.   Notice of Adjustment..........................................................................28
   Section 4.11.   Notice of Certain Transactions................................................................28
   Section 4.12.   Effect of Reclassifications, Consolidations, Mergers or Sales on Conversion Privilege.........28
   Section 4.13.   Trustee's Disclaimer..........................................................................29
   Section 4.14.   Voluntary Reduction...........................................................................29

                                                   ARTICLE 5.
                                                 SUBORDINATION

   Section 5.01.   Agreement to Subordinate......................................................................30
   Section 5.02.   Liquidation; Dissolution; Bankruptcy..........................................................30
   Section 5.03.   Default on Designated Senior Indebtedness.....................................................30
   Section 5.04.   Acceleration of Notes.........................................................................31
   Section 5.05.   When Distribution Must Be Paid Over...........................................................31
   Section 5.06.   Notice by Company.............................................................................32
   Section 5.07.   Subrogation...................................................................................32
   Section 5.08.   Relative Rights...............................................................................32
   Section 5.09.   Subordination May Not Be Impaired by Company..................................................32
   Section 5.10.   Distribution or Notice to Representative......................................................32
   Section 5.11.   Rights of Trustee and Paying Agent............................................................33
   Section 5.12.   Authorization to Effect Subordination.........................................................33
   Section 5.13.   Amendments....................................................................................33
   Section 5.14.   Agreement to Subordinate Unaffected...........................................................33
   Section 5.15.   Certain Conversions Deemed Payment............................................................33

                                                   ARTICLE 6.
                                                   COVENANTS

   Section 6.01.   Payment of Notes..............................................................................34
   Section 6.02.   Maintenance of Office or Agency...............................................................34
   Section 6.03.   Reports.......................................................................................35
   Section 6.04.   Rule 144A Information Requirement.............................................................35
   Section 6.05.   Compliance Certificate........................................................................35
   Section 6.06.   Taxes.........................................................................................36
   Section 6.07.   Stay, Extension and Usury Laws................................................................36
   Section 6.08.   Corporate Existence...........................................................................36
   Section 6.09.   Offer to Repurchase Upon Change of Control....................................................36
   Section 6.10.   Payment of Additional Interest................................................................39

                                                 ARTICLE 7.
                                                 SUCCESSORS

   Section 7.01.   Merger, Consolidation, or Sale of Assets......................................................39
   Section 7.02.   Successor Corporation Substituted.............................................................40

                                                  ARTICLE 8.
                                           DEFAULTS AND REMEDIES

   Section 8.01.   Events of Default.............................................................................40

</TABLE>




                                       ii
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<TABLE>
<CAPTION>
<S>                <C>                                                                                          <C>
   Section 8.02.   Acceleration..................................................................................41
   Section 8.03.   Other Remedies................................................................................41
   Section 8.04.   Waiver of Past Defaults.......................................................................42
   Section 8.05.   Control by Majority...........................................................................42
   Section 8.06.   Limitation on Suits...........................................................................42
   Section 8.07.   Rights of Holders of Notes to Receive Payment.................................................42
   Section 8.08.   Collection Suit by Trustee....................................................................43
   Section 8.09.   Trustee May File Proofs of Claim..............................................................43
   Section 8.10.   Priorities....................................................................................43
   Section 8.11.   Undertaking for Costs.........................................................................44

                                                   ARTICLE 9.
                                                    TRUSTEE

   Section 9.01.   Duties of Trustee.............................................................................44
   Section 9.02.   Rights of Trustee.............................................................................45
   Section 9.03.   Individual Rights of Trustee..................................................................46
   Section 9.04.   Trustee's Disclaimer..........................................................................46
   Section 9.05.   Notice of Defaults............................................................................46
   Section 9.06.   Reports by Trustee to Holders of the Notes....................................................46
   Section 9.07.   Compensation and Indemnity....................................................................46
   Section 9.08.   Replacement of Trustee........................................................................47
   Section 9.09.   Successor Trustee by Merger, etc..............................................................48
   Section 9.10.   Eligibility; Disqualification.................................................................48
   Section 9.11.   Preferential Collection of Claims Against Company.............................................48

                                                   ARTICLE 10.
                                          SATISFACTION AND DISCHARGE

   Section 10.01.     Satisfaction and Discharge.................................................................49
   Section 10.02.     Application of Trust Money.................................................................49
   Section 10.03.     Repayment to Company.......................................................................50
   Section 10.04.     Reinstatement..............................................................................50

                                                 ARTICLE 11.
                                      AMENDMENT, SUPPLEMENT AND WAIVER

   Section 11.01.     Without Consent of Holders of Notes........................................................50
   Section 11.02.     With Consent of Holders of Notes...........................................................51
   Section 11.03.     Compliance with Trust Indenture Act........................................................52
   Section 11.04.     Revocation and Effect of Consents..........................................................52
   Section 11.05.     Notation on or Exchange of Notes...........................................................53
   Section 11.06.     Trustee to Sign Amendments, etc............................................................53

                                                 ARTICLE 12.
                                                MISCELLANEOUS

   Section 12.01.     Trust Indenture Act Controls...............................................................53
   Section 12.02.     Notices....................................................................................53
   Section 12.03.     Communication by Holders of Notes with Other Holders of Notes..............................54
   Section 12.04.     Certificate and Opinion as to Conditions Precedent.........................................54
   Section 12.05.     Statements Required in Certificate or Opinion..............................................55
   Section 12.06.     Rules by Trustee and Agents................................................................55

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<TABLE>
<CAPTION>

<S>                   <C>                                                                                        <C>
   Section 12.07.     No Personal Liability of Directors, Officers, Employees and Stockholders...................55
   Section 12.08.     Governing Law..............................................................................55
   Section 12.09.     No Adverse Interpretation of Other Agreements..............................................56
   Section 12.10.     Successors.................................................................................56
   Section 12.11.     Severability...............................................................................56
   Section 12.12.     Counterpart Originals......................................................................56
   Section 12.13.     Table of Contents, Headings, etc...........................................................56

</TABLE>

                                    EXHIBITS

Exhibit A         FORM OF NOTE







                                       iv
<PAGE>   6
         INDENTURE dated as of May 7, 2001 between EMCORE Corporation, a New
Jersey corporation (the "COMPANY"), and Wilmington Trust Company, as trustee
(the "TRUSTEE").

         The Company and the Trustee agree as follows for the benefit of each
other and for the equal and ratable benefit of the Holders of the 5% Convertible
Subordinated Notes due 2006 (the "NOTES"):

                                   ARTICLE 1.
                          DEFINITIONS AND INCORPORATION
                                  BY REFERENCE

SECTION 1.01. DEFINITIONS.

         "144A GLOBAL NOTE" means a global note substantially in the form of
Exhibit A hereto bearing the Global Note Legend and the Private Placement Legend
and deposited with or on behalf of, and registered in the name of, the
Depositary or its nominee that will be issued in a denomination equal to the
outstanding principal amount of the Notes sold in reliance on Rule 144A.

         "ADDITIONAL INTEREST" means all Additional Interest then owing pursuant
to Section 5 of the Registration Rights Agreement.

         "AFFILIATE" of any specified Person means any other Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person. For purposes of this definition, "control"
(including, with correlative meanings, the terms "controlling," "controlled by"
and "under common control with"), as used with respect to any Person, shall mean
the possession, directly or indirectly, of the power to direct or cause the
direction of the management or policies of such Person, whether through the
ownership of voting securities, by agreement or otherwise; PROVIDED, HOWEVER,
that beneficial ownership of 10% or more of the voting securities of a Person
shall be deemed to be control.

         "AGENT" means any Registrar, Paying Agent or co-registrar.

         "APPLICABLE PROCEDURES" means, with respect to any transfer or exchange
of or for beneficial interests in any Global Note, the rules and procedures of
the Depositary, Euroclear and Cedel that apply to such transfer or exchange.

         "BANKRUPTCY LAW" means Title 11, U.S. Code or any similar federal or
state law for the relief of debtors.

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

         "BROKER-DEALER" has the meaning set forth in the Registration Rights
Agreement.

         "BUSINESS DAY" means any day other than a Legal Holiday.

         "CAPITAL LEASE OBLIGATION" means, at the time any determination thereof
is to be made, the amount of the liability in respect of a capital lease that
would at such time be required to be capitalized on a balance sheet in
accordance with GAAP.




                                       1
<PAGE>   7

         "CAPITAL STOCK" means any and all shares, interests, participations,
rights or other equivalents (however designated) of corporate stock, including,
without limitation, with respect to partnerships, partnership interests (whether
general or limited) and any other interest or participation that confers on a
Person the right to receive a share of the profits and losses of, or
distributions of assets of, such partnership.

         "CEDEL" means Cedel Bank, SA., and any and all successors thereto.

         "CLOSING SALE PRICE" means the last reported sales price or, in case no
such reported sale takes place on such date, the average of the reported closing
bid and asked prices in either case on The Nasdaq National Market or, if the
Common Stock is not listed or admitted to trading on The Nasdaq National Market,
on the principal national securities exchange on which the Common Stock is
listed or admitted to trading or, if not listed or admitted to trading on The
Nasdaq National Market or any national securities exchange, the last reported
sales price of the Common Stock as quoted on NASDAQ or, in case no reported
sales takes place, the average of the closing bid and asked prices as quoted on
NASDAQ or any comparable system or, if the Common Stock is not quoted on NASDAQ
or any comparable system, the closing sales price or, in case no reported sale
takes place, the average of the closing bid and asked prices, as furnished by
any two members of the National Association of Securities Dealers, Inc. selected
from time to time by the Company for that purpose.

         "COMPANY" means the issuer, and any and all successors thereto.

         "COMMON STOCK" means the common stock, no par value per share, of the
Company.

         "CORPORATE TRUST OFFICE OF THE TRUSTEE" shall be at the address of the
Trustee specified in Section 11.02 hereof or such other address as to which the
Trustee may give notice to the Company.

         "CREDIT AGREEMENT" means the Amended and Restated Revolving Loan and
Security Agreement, dated as of March 1, 2001, between the Company and First
Union National Bank.

         "CUSTODIAN" means the Trustee, as custodian with respect to the Global
Notes or any successor entity thereto.

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

         "DEFINITIVE NOTE" means a certificated Note registered in the name of
the Holder thereof and issued in accordance with Section 2.06 hereof,
substantially in the form of Exhibit A hereto except that such Note shall not
bear the Global Note Legend and shall not have the "Schedule of Exchanges of
Interests in the Global Note" attached thereto.

         "DEPOSITARY" means, with respect to any Global Notes, the Person
specified in Section 2.03 hereof as the Depositary with respect to such Global
Notes, and any and all successors thereto appointed as depositary hereunder and
having become such pursuant to the applicable provision of this Indenture.

         "DESIGNATED SENIOR INDEBTEDNESS" means (i) any Indebtedness outstanding
under the Credit Agreement and (ii) any other Senior Indebtedness permitted
hereunder the principal amount of which is $10.0 million or more and that has
been designated by the Company as "Designated Senior Indebtedness" at such time
as the Credit Agreement is no longer outstanding.




                                       2
<PAGE>   8

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

         "EUROCLEAR" means Morgan Guaranty Trust Company of New York, Brussels
office, as operator of the Euroclear system, and any and all successors thereto.

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

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

         "GLOBAL NOTES" means, individually and collectively, each of the
Restricted Global Notes and the Unrestricted Global Notes, substantially in the
form of Exhibit A hereto issued in accordance with this Indenture.

         "GLOBAL NOTE LEGEND" means the legend set forth in footnote 1 to
Exhibit A hereto, which is required to be placed on all Global Notes issued
under this Indenture.

         "GOVERNMENT SECURITIES" means direct obligations of, or obligations
guaranteed by, the United States of America, and the payment for which the
United States pledges its full faith and credit.

         "HEDGING OBLIGATIONS" means, with respect to any Person, the
obligations of such Person under (i) interest rate swap agreements, interest
rate cap agreements and interest rate collar agreements and (ii) other
agreements or arrangements designed to protect such Person against fluctuations
in interest rates or the value of foreign currencies purchased or received by
the Company in the ordinary course of business.

         "HOLDER" means a Person in whose name a Note is registered.

         "INDEBTEDNESS" means, with respect to any Person, without duplication,
(a) all indebtedness, obligations and other liabilities (contingent or
otherwise) of such Person for borrowed money (including obligations of such
Person in respect of overdrafts, foreign exchange contracts, currency exchange
agreements, interest rate protection agreements, and any loans or advances from
banks, whether or not evidenced by notes or similar instruments) or evidenced by
credit or loan agreements, bonds, debentures, notes or other written obligations
(whether or not the recourse of the lender is to the whole of the assets of such
Person or to only a portion thereof) (other than any accounts payable or other
accrued current liability or obligation incurred in the ordinary course of
business in connection with the obtaining of materials or services), (b) all
reimbursement obligations and other liabilities (contingent or otherwise) of
such Person with respect to letters of credit, bank guarantees or bankers'
acceptances, (c) all obligations and liabilities (contingent or otherwise) of
such Person in respect of leases of such Person required, in conformity with
generally accepted accounting principles, to be accounted for as capitalized
lease obligations on the balance sheet of such Person, (d) all obligations of
such Person evidenced by a note or similar instrument given in connection with
the acquisition of any business, properties or assets of any kinds, (e) all
obligations of such Person issued or assumed as the deferred purchase price of
property or services (excluding trade account payables and accrued liabilities
arising in the ordinary course of





                                       3
<PAGE>   9

business), (f) all obligations (contingent or otherwise) of such Person under
any lease or related document (including a purchase agreement) in connection
with the lease of real property or improvements (or any personal property
included as part of any such lease) which provides that such Person is
contractually obligated to purchase or cause a third party to purchase the
leased property and thereby guarantee a minimum residual value of the leased
property to the lessor and the obligations of such Person under such lease or
related document to purchase or to cause a third party to purchase such leased
property (whether or not such lease transaction is characterized as an operating
lease or a capitalized lease in accordance with generally accepted accounting
principles), (g) all obligations (contingent or otherwise) of such Person with
respect to any interest rate, currency or other swap, cap, floor or collar
agreement, hedge agreement, forward contract, or other similar instrument or
agreement or foreign currency hedge, exchange, purchase or similar instrument or
agreement, (h) all direct or indirect guaranties, agreements to be jointly
liable or similar agreements by such Person in respect of, and obligations or
liabilities (contingent or otherwise) of such Person to purchase or otherwise
acquire or otherwise assure a creditor against loss in respect of, indebtedness,
obligations or liabilities of another Person of the kind described in clauses
(a) through (g), and (i) any and all deferrals, renewals, extensions and
refundings of, or amendments, modifications or supplements to, any indebtedness,
obligation or liability of the kind described in clauses (a) through (h).

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

         "INDIRECT PARTICIPANT" means a Person who holds a beneficial interest
in a Global Note through a Participant.

         "LEGAL HOLIDAY" means a Saturday, a Sunday or a day on which banking
institutions in the City of New York or Wilmington, Delaware or at a place of
payment are authorized by law, regulation or executive order to remain closed.
If a payment date is a Legal Holiday at a place of payment, payment may be made
at that place on the next succeeding day that is not a Legal Holiday, and no
interest shall accrue on such payment for the intervening period.

         "NON-U.S. PERSON" means a Person who is not a U.S. Person.

         "NOTES" has the meaning assigned to it in the preamble to this
Indenture.

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

         "OFFERING" means the offering of the Notes by the Company.

         "OFFICER" means, with respect to any Person, the Chairman of the Board,
the Chief Executive Officer, the President, the Chief Operating Officer, the
Chief Financial Officer, the Treasurer, any Assistant Treasurer, the Controller,
the Secretary or any Vice-President of such Person.

         "OFFICERS' CERTIFICATE" means a certificate signed on behalf of the
Company by two Officers of the Company, one of whom must be the principal
executive officer, the principal financial officer, the treasurer or the
principal accounting officer of the Company, that meets the requirements of
Section 12.05 hereof.





                                       4
<PAGE>   10

         "OPINION OF COUNSEL" means an opinion from legal counsel who is
reasonably acceptable to the Trustee, that meets the requirements of Section
12.05 hereof. The counsel may be an employee of or counsel to the Company, any
Subsidiary of the Company or the Trustee.

         "PARTICIPANT" means, with respect to the Depositary, Euroclear or
Cedel, a Person who has an account with the Depositary, Euroclear or Cedel,
respectively (and, with respect to DTC, shall include Euroclear and Cedel).

         "PERMITTED JUNIOR SECURITIES" means Equity Interests in the Company or
debt securities that are subordinated to all Senior Indebtedness (and any debt
securities issued in exchange for Senior Indebtedness) to substantially the same
extent as, or to a greater extent than, the Notes are subordinated to Senior
Indebtedness pursuant to the Indenture.

         "PERSON" means any individual, corporation, partnership, limited
liability company, joint venture, association, joint-stock company, trust,
unincorporated organization or government or agency or political subdivision
thereof (including any subdivision or ongoing business of any such entity or
substantially all of the assets of any such entity, subdivision or business).

         "PRIVATE PLACEMENT LEGEND" means the legend set forth in footnote 2 to
Exhibit A hereto to be placed on all Notes issued under this Indenture except
where otherwise permitted by the provisions of this Indenture.

         "PURCHASE AGREEMENT" means the Purchase Agreement, dated as of May 1,
2001, by and between the Company and Credit Suisse First Boston Corporation, as
representative of the several purchasers.

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

         "REGISTRATION RIGHTS AGREEMENT" means the Registration Rights
Agreement, dated as of May 7, 2001, by and among the Company and the other
parties named on the signature pages thereof, as such agreement may be amended,
modified or supplemented from time to time.

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

         "REGULATION S GLOBAL NOTE" means a global Note bearing the Private
Placement Legend and deposited with or on behalf of the Depositary and
registered in the name of the Depositary or its nominee, issued in a
denomination equal to the outstanding principal amount of the Notes initially
sold in reliance on Rule 903 of Regulation S.

         "REPRESENTATIVE" means the indenture trustee or other trustee, agent or
representative for any Senior Indebtedness.

         "RESPONSIBLE OFFICER," when used with respect to the Trustee, means any
officer within the Corporate Trust Administration of the Trustee (or any
successor group of the Trustee) with direct responsibilities 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 his knowledge of and familiarity with the particular subject.

         "RESTRICTED DEFINITIVE NOTE" means a Definitive Note bearing the
Private Placement Legend.




                                       5
<PAGE>   11

         "RESTRICTED GLOBAL NOTE" means a Global Note bearing the Private
Placement Legend.

         "RESTRICTED PERIOD" means the 40-day restricted period as defined in
Regulation S.

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

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

         "RULE 903" means Rule 903 promulgated under the Securities Act.

         "RULE 904" means Rule 904 promulgated the Securities Act.

         "SEC" means the Securities and Exchange Commission.

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

         "SENIOR INDEBTEDNESS" means (i) the principal of, premium, if any,
interest including all interest accruing subsequent to the commencement of any
bankruptcy or similar proceeding, whether or not a claim for post-petition
interest is allowable as a claim in any such proceeding, and rent payable on or
in connection with, Indebtedness of the Company unless the instrument under
which such Indebtedness is incurred expressly provides that it is on a parity
with or subordinated in right of payment to the Notes, and (ii) all Obligations
with respect to any of the foregoing, whether secured or unsecured, absolute or
contingent, due or to become due, outstanding on the date hereof or hereafter
credited incurred, assumed, guaranteed or in effect guaranteed by the Company,
including all deferrals, renewals, extensions and refundings of or amendments,
modifications or supplements to, the foregoing. Notwithstanding anything to the
contrary in the foregoing, Senior Indebtedness shall not include (x) any
Indebtedness of the Company to any of its Subsidiaries or other Affiliates, (y)
any Indebtedness incurred for the purchase of goods or materials or for services
obtained in the ordinary course of business (other than with the proceeds of
revolving credit borrowings permitted hereby) and (z) any Indebtedness that is
incurred in violation of this Indenture.

         "SHELF REGISTRATION STATEMENT" means the Shelf Registration Statement
as defined in the Registration Rights Agreement.

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

         "TIA" means the Trust Indenture Act of 1939 (15 U.S.C. ss.ss.
77aaa-77bbbb) as in effect on the date on which this Indenture is qualified
under the TIA; provided, however, that in the event the Trust Indenture Act of
1939 is amended after such date, "TIA" means, to the extent required by any such
amendment, the Trust Indenture Act of 1939 as so amended.

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

         "UNRESTRICTED GLOBAL NOTE" means a permanent global Note substantially
in the form of Exhibit A attached hereto that bears the Global Note Legend and
that has the "Schedule of Exchanges of




                                       6
<PAGE>   12

Interests in the Global Note" attached thereto, and that is deposited with or on
behalf of and registered in the name of the Depositary, representing a series of
Notes that do not bear the Private Placement Legend.

         "UNRESTRICTED DEFINITIVE NOTE" means one or more Definitive Notes that
do not bear and are not required to bear the Private Placement Legend.

         "U.S. PERSON" means a U.S. person as defined in Rule 902(o) under the
Securities Act.

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

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

SECTION 1.02. OTHER DEFINITIONS.

                                                               Defined in
        Term                                                     Section
        ----                                                     -------

        "AUTHENTICATION ORDER"...............................     2.02
        "CHANGE OF CONTROL" .................................     6.09
        "CHANGE OF CONTROL OFFER"............................     6.09
        "CHANGE OF CONTROL PAYMENT"..........................     6.09
        "CHANGE OF CONTROL PAYMENT DATE".....................     6.09
        "CHANGE OF CONTROL PAYMENT NOTICE" ..................     6.09
        "DETERMINATION DATE" ................................     4.06
        "EVENT OF DEFAULT"...................................     8.01
        "EXPIRATION DATE" ...................................     4.06
        "EXPIRATION DATE" ...................................     4.06
        "MAKE-WHOLE PAYMENT" ................................     3.07
        "NOTICE DATE" .......................................     3.07
        "PAYING AGENT".......................................     2.03
        "PROVISIONAL REDEMPTION" ............................     3.07
        "PROVISIONAL REDEMPTION DATE" .......................     3.07
        "PROVISIONAL REDEMPTION PRICE" ......................     3.07
        "PURCHASED SHARES" ..................................     4.06
        "REGISTRAR"..........................................     2.03
        "TENDER OFFER" ......................................     4.06
        "TRIGGERING DISTRIBUTION"............................     4.06

SECTION 1.03. INCORPORATION BY REFERENCE OF TRUST INDENTURE ACT.

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




                                       7
<PAGE>   13

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

         "INDENTURE SECURITIES" means the Notes;

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

         "INDENTURE TO BE QUALIFIED" means this Indenture;

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

         "OBLIGOR" on the Notes means the Company and any successor obligor upon
the Notes.

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

SECTION 1.04. RULES OF CONSTRUCTION.

         Unless the context otherwise requires:

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

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

         (c) "or" is not exclusive;

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

         (e) provisions apply to successive events and transactions; and

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

                                   ARTICLE 2.
                                    THE NOTES

SECTION 2.01. FORM AND DATING.

         (a) GENERAL. The Notes and the Trustee's certificate of authentication
shall be substantially in the form of Exhibit A hereto. The Notes may have
notations, legends or endorsements required by law, stock exchange rule or
usage. Each Note shall be dated the date of its authentication. The Notes shall
be in denominations of $1,000 and integral multiples thereof.

         The terms and provisions contained in the Notes shall constitute, and
are hereby expressly made, a part of this Indenture and the Company and the
Trustee, by their execution and delivery of this Indenture, expressly agree to
such terms and provisions and to be bound thereby. However, to the extent any
provision of any Note conflicts with the express provisions of this Indenture,
the provisions of this Indenture shall govern and be controlling.





                                       8
<PAGE>   14

         (b) GLOBAL NOTES. Notes issued in global form shall be substantially in
the form of Exhibit A attached hereto (including the Global Note Legend thereon
and the "Schedule of Exchanges of Interests in the Global Note" attached
thereto). Notes issued in definitive form shall be substantially in the form of
Exhibit A attached hereto (but without the Global Note Legend thereon and
without the "Schedule of Exchanges of Interests in the Global Note" attached
thereto). Each Global Note shall represent such of the outstanding Notes as
shall be specified therein and each shall provide that it shall represent the
aggregate principal amount of outstanding Notes from time to time endorsed
thereon and that the aggregate principal amount of outstanding Notes represented
thereby may from time to time be reduced or increased, as appropriate, to
reflect exchanges and redemptions. Any endorsement of a Global Note to reflect
the amount of any increase or decrease in the aggregate principal amount of
outstanding Notes represented thereby shall be made by the Trustee or the
Custodian, at the direction of the Trustee, in accordance with instructions
given by the Holder thereof as required by Section 2.12 hereof.

         (c) EUROCLEAR AND CEDEL PROCEDURES APPLICABLE. The provisions of the
"Operating Procedures of the Euroclear System" and "Terms and Conditions
Governing Use of Euroclear" and the "General Terms and Conditions of Cedel Bank"
and "Customer Handbook" of Cedel Bank shall be applicable to transfers of
beneficial interests in the Regulation S Global Notes that are held by
Participants through Euroclear or Cedel Bank.

SECTION 2.02. EXECUTION AND AUTHENTICATION.

         An Officer shall sign the Notes for the Company by manual or facsimile
signature. The Company's seal shall be reproduced on the Notes and may be in
facsimile form.

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

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

         The Trustee shall, upon a written order of the Company signed by an
Officer (an "AUTHENTICATION ORDER"), authenticate Notes for original issue in
the aggregate principal amount of up to $175,000,000. The Authentication Order
shall specify the amount of Notes to be authenticated, shall provide that all
Notes will be represented by a Restricted Global Note and the date on which each
original issue of Notes is to be authenticated. The aggregate principal amount
of Notes outstanding at any time may not exceed $175,000,000 except as provided
in Section 2.07 hereof.

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

SECTION 2.03. REGISTRAR, PAYING AGENT AND CONVERSION AGENT.

         The Company shall maintain an office or agency where Notes may be
presented for registration of transfer or for exchange ("REGISTRAR"), an office
or agency where Notes may be presented for payment ("PAYING AGENT"), an office
or agency where Notes may be presented for conversion ("CONVERSION AGENT") and
an office or agent where notices and demands to or upon the Company in respect
of the




                                       9
<PAGE>   15

Notes and this Indenture may be served. The Registrar shall keep a register of
the Notes and of their registration of transfer and exchange. The Company may
appoint one or more co-registrars and one or more additional paying agents and
conversion agents. The term "Registrar" includes any co-registrar, the term
"Paying Agent" includes any additional paying agent and the term "Conversion
Agent" includes any additional conversion agent. The Company may change any
Paying Agent, Conversion Agent or Registrar without notice to any Holder. The
Company shall notify the Trustee in writing of the name and address of any Agent
not a party to this Indenture. If the Company fails to appoint or maintain
another entity as Registrar, Paying Agent, Conversion Agent or agent for service
of notices and demands in any place required by this Indenture, or fails to give
the foregoing notice, the Trustee shall act as such. The Company or any of its
Subsidiaries may act as Paying Agent, Conversion Agent or Registrar.

         The Company initially appoints The Depository Trust Company ("DTC") to
act as Depositary with respect to the Global Notes.

         The Company initially appoints the Trustee to act as the Registrar,
Paying Agent and Conversion Agent and to act as Custodian with respect to the
Global Notes.

SECTION 2.04. PAYING AGENT TO HOLD MONEY IN TRUST.

         Prior to 10:00 a.m., New York City time, on each due date of the
principal of, premium, if any, or interest (including Additional Interest), on
any Notes, the Company shall deposit with the Paying Agent a sum sufficient to
pay such principal, premium, if any, or interest so becoming due. The Company
shall require each Paying Agent other than the Trustee to agree in writing that
the Paying Agent will hold in trust for the benefit of Holders or the Trustee
all money held by the Paying Agent for the payment of principal, premium or
Additional Interest, if any, or interest on the Notes, and will notify the
Trustee of any default by the Company in making any such payment. While any such
default continues, the Trustee may require a Paying Agent to pay all money held
by it to the Trustee. The Company at any time may require a Paying Agent to pay
all money held by it to the Trustee. Upon payment over to the Trustee, the
Paying Agent (if other than the Company or a Subsidiary) shall have no further
liability for the money. If the Company or a Subsidiary acts as Paying Agent, it
shall before 10:00 a.m. New York City time on each due date of the principal of,
premium, if any, or interest (including Additional Interest), segregate and hold
in a separate trust fund for the benefit of the Holders all money held by it as
Paying Agent. Upon any bankruptcy or reorganization proceedings relating to the
Company, the Trustee shall serve as Paying Agent for the Notes.

SECTION 2.05. HOLDER LISTS.

         The Trustee shall preserve in as current a form as is reasonably
practicable the most recent list available to it of the names and addresses of
all Holders and shall otherwise comply with TIA ss. 312(a). If the Trustee is
not the Registrar, the Company shall furnish to the Trustee at least seven
Business Days before each interest payment date and at such other times as the
Trustee may request in writing, a list in such form and as of such date as the
Trustee may reasonably require of the names and addresses of the Holders of
Notes and the Company shall otherwise comply with TIA ss. 312(a).

SECTION 2.06. TRANSFER AND EXCHANGE.

         (a) Subject to compliance with any applicable additional requirements
contained in Section 2.12, when a Note is presented to a Registrar with a
request to register a transfer thereof or to exchange such Note for an equal
principal amount of Notes of other authorized denominations, the Registrar shall





                                       10
<PAGE>   16

register the transfer or make the exchange as requested; provided, however, that
every Note presented or surrendered for registration of transfer or exchange
shall be duly endorsed or accompanied by an assignment form and, if applicable,
a transfer certificate each in the form included in Exhibit A, and in form
satisfactory to the Registrar duly executed by the Holder thereof or its
attorney duly authorized in writing. To permit registration of transfers and
exchanges, upon surrender of any Note for registration of transfer or exchange
at an office or agency maintained pursuant to Section 2.03, the Company shall
execute and the Trustee shall authenticate Notes of a like aggregate principal
amount at the Registrar's request. Any exchange or registration of transfer
shall be without charge, except that the Company or the Registrar may require
payment of a sum sufficient to cover any tax or other governmental charge that
may be imposed in relation thereto, and provided, that this sentence shall not
apply to any exchange pursuant to Section 2.07, 2.10, 2.12(a), 3.06, 6.09(a)(7),
4.02 (last paragraph) or 11.05.

         Neither the Company, any Registrar nor the Trustee shall be required to
exchange or register a transfer of (a) any Notes for a period of 15 days next
preceding any mailing of a notice of Notes to be redeemed, (b) any Notes or
portions thereof selected or called for redemption (except, in the case of
redemption of a Note in part, the portion not to be redeemed) or (c) any Notes
or portions thereof in respect of which a Note has been delivered and not
withdrawn by the Holder thereof (except, in the case of the purchase of a Note
in part, the portion not to be purchased).

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

         (b) Any Registrar appointed pursuant to Section 2.03 hereof shall
provide to the Trustee such information as the Trustee may reasonably require in
connection with the delivery by such Registrar of Notes upon registration of
transfer or exchange of Notes.

         (c) Each Holder of a Note agrees to indemnify the Company, the
Registrar and the Trustee against any liability that may result from the
registration of transfer, exchange or assignment of such Holder's Note in
violation of any provision of this Indenture and/or applicable United States
federal or state securities law.

         The Trustee shall have no obligation or duty to monitor, determine or
inquire as to compliance with any restrictions on registration of transfer
imposed under this Indenture or under applicable law with respect to any
transfer of any interest in any Note (including any transfers between or among
Participants or other beneficial owners of interests in any Global Note) 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 2.07. REPLACEMENT NOTES.

         If any mutilated Note is surrendered to the Trustee or the Company and
the Trustee receives evidence to its satisfaction of the destruction, loss or
theft of any Note, the Company shall issue and the Trustee, upon receipt of an
Authentication Order, shall authenticate a replacement Note if the Trustee's
requirements are met. If required by the Trustee or the Company, an indemnity
bond must be supplied by the Holder that is sufficient in the judgment of the
Trustee and the Company to protect the Company, the Trustee, any Agent and any
authenticating agent from any loss that any of them may suffer if a Note is
replaced. The Company may charge for its expenses in replacing a Note.




                                       11
<PAGE>   17

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

SECTION 2.08. OUTSTANDING NOTES.

         The Notes outstanding at any time are all the Notes authenticated by
the Trustee except for those canceled by it, those delivered to it for
cancellation, those reductions in the interest in a Global Note effected by the
Trustee in accordance with the provisions hereof, and those described in this
Section as not outstanding. Except as set forth in Section 2.09 hereof, a Note
does not cease to be outstanding because the Company or an Affiliate of the
Company holds the Note.

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

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

         If the Paying Agent (other than the Company, a Subsidiary or an
Affiliate of any thereof) holds, on a redemption date, a Change in Control
Payment Date or maturity date, money sufficient to pay Notes payable on that
date, then on and after that date such Notes shall be deemed to be no longer
outstanding and shall cease to accrue interest.

SECTION 2.09. TREASURY NOTES.

         In determining whether the Holders of the required principal amount of
Notes have concurred in any notice, direction, waiver or consent, Notes owned by
the Company, or by any Person directly or indirectly controlling or controlled
by or under direct or indirect common control with the Company, shall be
considered as though not outstanding, except that for the purposes of
determining whether the Trustee shall be protected in relying on any such
notice, direction, waiver or consent, only Notes that the Trustee knows are so
owned shall be so disregarded.

SECTION 2.10. TEMPORARY NOTES.

         Until certificates representing Notes are ready for delivery, the
Company may prepare and execute, and the Trustee, upon receipt of an
Authentication Order, shall authenticate and deliver temporary Notes. Temporary
Notes shall be substantially in the form of definitive Notes but may have
variations that the Company considers appropriate for temporary Notes and as
shall be reasonably acceptable to the Trustee. Without unreasonable delay, the
Company shall prepare and the Trustee, upon receipt of an Authentication Order,
shall authenticate and deliver definitive Notes in exchange for temporary Notes.

         Holders of temporary Notes shall be entitled to all of the benefits of
this Indenture.

SECTION 2.11. CANCELLATION.

         The Company at any time may deliver Notes to the Trustee for
cancellation. The Registrar, Paying Agent and Conversion Agent shall forward to
the Trustee any Notes surrendered to them for registration of transfer,
exchange, redemption, payment or conversion. The Trustee and no one else shall
cancel all Notes surrendered for registration of transfer, exchange, redemption,
payment, conversion, replacement or cancellation and shall destroy canceled
Notes (subject to the record retention requirement




                                       12
<PAGE>   18

of the Exchange Act), in accordance with their normal procedures. All Notes
which are redeemed, purchased or otherwise acquired by the Company or any of its
Subsidiaries prior to the maturity date shall be delivered to the Trustee for
cancellation. Certification of the destruction of all canceled Notes shall be
delivered to the Company. The Company may not hold or resell such Notes or issue
new Notes to replace Notes that it has purchase or otherwise acquired or that
have been delivered to the Trustee for cancellation.

SECTION 2.12. ADDITIONAL TRANSFER AND EXCHANGE REQUIREMENTS.

         (a) TRANSFER AND EXCHANGE OF GLOBAL NOTES.

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

                  (2) Notwithstanding any other provisions of this Indenture
         other than the provisions set forth in Section 2.12(a)(1), a Global
         Note may not be transferred as a whole except by the Depositary to a
         nominee of the Depositary or by a nominee of the Depositary to the
         Depositary or another nominee of the Depositary or by the Depositary or
         any such nominee to a successor Depositary or a nominee of such
         successor Depositary.

         (b) TRANSFER AND EXCHANGE OF DEFINITIVE NOTES. In the event that
Definitive Notes are issued in exchange for beneficial interests in Global Notes
in accordance with Section 2.12(a)(1) of this Indenture, on or after such event
when Definitive Notes are presented by a Holder to a Registrar with a request:

                  (x) to register the transfer of the Definitive Notes to a
         person who will take delivery thereof in the form of Definitive Notes
         only; or

                  (y) to exchange such Definitive Notes for an equal principal
         amount of Definitive Notes of other authorized denominations,

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




                                       13
<PAGE>   19
                  (1) shall be duly endorsed or accompanied by a written
         instrument of transfer in accordance with the proviso to the first
         paragraph of Section 2.06(a); and

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

                           (i) if such Restricted Definitive Note is being
                  delivered to the Registrar by a Holder for registration in the
                  name of such Holder, without transfer, or such Restricted
                  Definitive Note is being transferred to the Company or a
                  Subsidiary of the Company, a certification to that effect from
                  such Holder (in substantially the form set forth in the
                  Transfer Certificate);

                           (ii) if such Restricted Definitive Note is being
                  transferred to a person the Holder reasonably believes is a
                  QIB in accordance with Rule 144A or is being transferred to a
                  Non-U.S. Person in an offshore transaction in accordance with
                  Rule 903 or Rule 904 or pursuant to an effective registration
                  statement under the Securities Act, a certification to that
                  effect from such Holder (in substantially the form set forth
                  in the Transfer Certificate); or

                           (iii) if such Restricted Definitive Note is being
                  transferred (A) pursuant to an exemption from the registration
                  requirements of the Securities Act in accordance with Rule 144
                  or (B) pursuant to an exemption from the registration
                  requirements of the Securities Act (other than pursuant to
                  Rule 144A, Rule 144, Rule 903 or Rule 904) and as a result of
                  which, in the case of a Note transferred pursuant to this
                  clause (B), such Note shall cease to be a "restricted
                  security" within the meaning of Rule 144, a certification to
                  that effect from the Holder (in substantially the form set
                  forth in the Transfer Certificate) and, if the Company or such
                  Registrar so requests, a customary opinion of counsel,
                  certificates and other information reasonably acceptable to
                  the Company and such Registrar to the effect that such
                  transfer is in compliance with the registration requirements
                  of the Securities Act.

         (c) TRANSFER OF A BENEFICIAL INTEREST IN A RESTRICTED GLOBAL NOTE FOR A
BENEFICIAL INTEREST IN AN UNRESTRICTED GLOBAL NOTE. Any person having a
beneficial interest in a Restricted Global Note may upon request, subject to the
Applicable Procedures, transfer such beneficial interest to a person who is
required or permitted to take delivery thereof in the form of a beneficial
interest in an Unrestricted Global Note. Upon receipt by the Trustee of written
instructions, or such other form of instructions as is customary for the
Depositary, from the Depositary or its nominee on behalf of any person having a
beneficial interest in a Restricted Global Note and the following additional
information and documents in such form as is customary for the Depositary from
the Depositary or its nominee on behalf of the person having such beneficial
interest in the Restricted Global Note (all of which may be submitted by
facsimile or electronically):

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

                  (2) if such beneficial interest is being transferred (i)
         pursuant to an exemption from the registration requirements of the
         Securities Act in accordance with Rule 144 or (ii) pursuant to an
         exemption from the registration requirements of the Securities Act
         (other




                                       14
<PAGE>   20

         than pursuant to Rule 144A, Rule 144, Rule 903 or Rule 904) and as a
         result of which, in the case of a Note transferred pursuant to this
         clause (ii), such Note shall cease to be a "restricted security" within
         the meaning of Rule 144, a certification to that effect from the
         transferor (in substantially the form set forth in the Transfer
         Certificate) and, if the Company or the Trustee so requests, a
         customary opinion of counsel, certificates and other information
         reasonably acceptable to the Company and the Trustee to the effect that
         such transfer is in compliance with the registration requirements of
         the Securities Act.

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

         (d) TRANSFER OF A BENEFICIAL INTEREST IN AN UNRESTRICTED GLOBAL NOTE
FOR A BENEFICIAL INTEREST IN A RESTRICTED GLOBAL NOTE. Any person having a
beneficial interest in an Unrestricted Global Note may upon request, subject to
the Applicable Procedures, transfer such beneficial interest to a person who is
required or permitted to take delivery thereof in the form of a Restricted
Global Note (it being understood that only QIBs may own beneficial interests in
Restricted Global Notes). Upon receipt by the Trustee of written instructions or
such other form of instructions as is customary for the Depositary, from the
Depositary or its nominee, on behalf of any person having a beneficial interest
in an Unrestricted Global Note and, in such form as is customary for the
Depositary, from the Depositary or its nominee on behalf of the person having
such beneficial interest in the Unrestricted Global Note (all of which may be
submitted by facsimile or electronically) a certification from the transferor
(in substantially the form set forth in the Transfer Certificate) to the effect
that such beneficial interest is being transferred to a person that the
transferor reasonably believes is a QIB in accordance with Rule 144A. The
Trustee, as a Registrar and Custodian, shall reduce or cause to be reduced the
aggregate principal amount of the Unrestricted Global Note by the appropriate
principal amount and shall increase or cause to be increased the aggregate
principal amount of the Restricted Global Note by a like principal amount. Such
transfer shall otherwise be effected in accordance with the Applicable
Procedures. If no Restricted Global Note is then outstanding, the Company shall
execute and the Trustee shall, upon receipt of an Authentication Order (which
the Company agrees to deliver promptly), authenticate and deliver a Restricted
Global Note.

         (e) TRANSFERS OF DEFINITIVE NOTES FOR BENEFICIAL INTEREST IN GLOBAL
NOTES. In the event that Definitive Notes are issued in exchange for beneficial
interests in Global Notes and, thereafter, the events or conditions specified in
Section 2.12(a)(1) which required such exchange shall cease to exist, the
Company shall mail notice to the Trustee and to the Holders stating that Holders
may exchange Definitive Notes for interests in Global Notes by complying with
the procedures set forth in this Indenture and briefly describing such
procedures and the events or circumstances requiring that such notice be given.
Thereafter, if Definitive Notes are presented by a Holder to a Registrar with a
request:

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




                                       15
<PAGE>   21

                  (y) to exchange such Definitive Notes for an equal principal
         amount of beneficial interests in a Global Note, which beneficial
         interests will be owned by the Holder transferring such Definitive
         Notes (provided that in the case of such an exchange, Restricted
         Definitive Notes may be exchanged only for Restricted Global Notes and
         Unrestricted Definitive Notes may be exchanged only for Unrestricted
         Global Notes),

the Registrar shall register the transfer or make the exchange as requested by
canceling such Definitive Note and causing, or directing the Custodian to cause,
the aggregate principal amount of the applicable Global Note to be increased
accordingly and, if no such Global Note is then outstanding, the Company shall
issue and the Trustee, upon receipt of an Authentication Order, shall
authenticate and deliver a new Global Note; provided, however, that the
Definitive Notes presented or surrendered for registration of transfer or
exchange:

                  (1) shall be duly endorsed or accompanied by a written
         instrument of transfer in accordance with the proviso to Section 2.06;

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

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

                           (ii) if such Restricted Definitive Note is being
                  transferred pursuant to (A) an exemption from the registration
                  requirements of the Securities Act in accordance with Rule 144
                  or (B) pursuant to an exemption from the registration
                  requirements of the Securities Act (other than pursuant to
                  Rule 144A, Rule 144, Rule 903 or Rule 904) and as a result of
                  which, in the case of a Note transferred pursuant to this
                  clause (B), such Note shall cease to be a "restricted
                  security" within the meaning of Rule 144, a certification to
                  that effect from such Holder (in substantially the form set
                  forth in the Transfer Certificate), and, if the Company or the
                  Registrar so requests, a customary opinion of counsel,
                  certificates and other information reasonably acceptable to
                  the Company and the Trustee to the effect that such transfer
                  is in compliance with the registration requirements of the
                  Securities Act;

                  (3) in the case of a Restricted Definitive Note to be
         transferred or exchanged for a beneficial interest in a Restricted
         Global Note, such request shall be accompanied by a certification from
         such Holder (in substantially the form set forth in the Transfer
         Certificate) to the effect that such Restricted Definitive Note is
         being transferred to a person the Holder reasonably believes is a QIB
         (which, in the case of an exchange, shall be such Holder) in accordance
         with Rule 144A or is being transferred to a Non-U.S. Person in an
         offshore transaction in accordance with Rule 903 or Rule 904;

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





                                       16
<PAGE>   22

                  (5) in the case of an Unrestricted Definitive Note to be
         transferred or exchanged for a beneficial interest in a Restricted
         Global Note, such request shall be accompanied by a certification from
         such Holder (in substantially the form set forth in the Transfer
         Certificate) to the effect that such Unrestricted Definitive Note is
         being transferred to a person the Holder reasonably believes is a QIB
         (which, in the case of an exchange, shall be such Holder) in accordance
         with Rule 144A or is being transferred to a Non-U.S. Person in an
         offshore transaction in accordance with Rule 903 or Rule 904.

         (f) LEGENDS.

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

                  (2) Upon any sale or transfer of a Restricted Global Note (w)
         after the expiration of the holding period applicable to sales of the
         Notes under Rule 144(k) of the Notes Act, (x) pursuant to Rule 144, (y)
         pursuant to an effective registration statement under the Notes Act or
         (z) pursuant to any other available exemption (other than Rule 144A)
         from the registration requirements of the Securities Act and as a
         result of which, in the case of a Note transferred pursuant to this
         clause (z), such Note shall cease to be a "restricted security" within
         the meaning of Rule 144:

                           (i) in the case of any Restricted Definitive Note,
                  any Registrar shall permit the Holder thereof to exchange such
                  Restricted Definitive Note for an Unrestricted Definitive
                  Note, or (under the circumstances described in Section
                  2.12(e)) to transfer such Restricted Definitive Note to a
                  transferee who shall take such Note in the form of a
                  beneficial interest in an Unrestricted Global Note, and in
                  each case shall rescind any restriction on the transfer of
                  such Note; provided, however, that the Holder of such
                  Restricted Definitive Note shall, in connection with such
                  exchange or transfer, comply with the other applicable
                  provisions of this Section 2.12; and

                           (ii) in the case of any beneficial interest in a
                  Restricted Global Note, the Trustee shall permit the
                  beneficial owner thereof to transfer such beneficial interest
                  to a transferee who shall take such interest in the form of a
                  beneficial interest in an Unrestricted Global Note and shall
                  rescind any restriction on transfer of such beneficial
                  interest; provided, that such Unrestricted Global Note shall
                  continue to be subject to the provisions of Section
                  2.12(a)(2); and provided, further, that the owner of such
                  beneficial interest shall, in connection with such transfer,
                  comply with the other applicable provisions of this Section
                  2.12.

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





                                       17
<PAGE>   23

                  (4) After the expiration of the holding period pursuant to
         Rule 144(k) of the Securities Act, the Company may with the consent of
         the Holder of a Restricted Global Note or Restricted Definitive Note,
         remove any restriction of transfer on such Note, and the Company shall
         execute, and the Trustee shall authenticate and deliver Notes that do
         not bear such legend and that do not have a Transfer Certificate
         attached thereto.

         (g) TRANSFERS TO THE COMPANY. Nothing in this Indenture or in the Notes
shall prohibit the sale or other transfer of any Notes (including beneficial
interests in Global Notes) to the Company or any of its Subsidiaries, which
Notes shall thereupon be cancelled in accordance with Section 2.11.

SECTION 2.13. CUSIP NUMBERS.

         The Company in issuing the Notes may use "CUSIP" numbers (if then
generally in use), and, if so, the Trustee shall use "CUSIP" numbers in notices
of redemption or purchase as a convenience to Holders; provided that any such
notice may state that no representation is made as to the correctness of such
numbers either as printed on the Notes or as contained in any notice of a
redemption or purchase and that reliance may be placed only on the other
identification numbers printed on the Notes, and any such redemption or purchase
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.

SECTION 2.14. DEFAULTED INTEREST.

         If the Company defaults in a payment of interest on the Notes, it shall
pay the defaulted interest in any lawful manner plus, to the extent lawful,
interest payable on the defaulted interest, to the Persons who are Holders on a
subsequent special record date, in each case at the rate provided in the Notes
and in Section 4.01 hereof. The Company shall notify the Trustee in writing of
the amount of defaulted interest proposed to be paid on each Note and the date
of the proposed payment. The Company shall fix or cause to be fixed each such
special record date and payment date, PROVIDED that no such special record date
shall be less than 10 days prior to the related payment date for such defaulted
interest. At least 15 days before the special record date, the Company (or, upon
the written request of the Company, the Trustee in the name and at the expense
of the Company) shall mail or cause to be mailed to Holders a notice that states
the special record date, the related payment date and the amount of such
interest to be paid.

                                   ARTICLE 3.
                            REDEMPTION AND PREPAYMENT

SECTION 3.01. NOTICES TO TRUSTEE.

         If the Company elects to redeem Notes pursuant to the provisional or
optional redemption provisions of Section 3.07 hereof, it shall furnish to the
Trustee, at least 20 days but not more than 60 days before a redemption date, an
Officers' Certificate setting forth (i) the clause of this Indenture pursuant to
which the redemption shall occur, (ii) the redemption date, (iii) the principal
amount of Notes to be redeemed and (iv) the redemption price.

SECTION 3.02. SELECTION OF NOTES TO BE REDEEMED.

         If less than all of the Notes are to be redeemed or purchased in an
offer to purchase at any time, the Trustee shall select the Notes to be redeemed
or purchased among the Holders of the Notes in




                                       18
<PAGE>   24

compliance with the requirements of the principal national securities exchange,
if any, on which the Notes are listed or, if the Notes are not so listed, on a
PRO RATA basis, by lot or in accordance with any other method the Trustee
considers fair and appropriate. In the event of partial redemption by lot, the
particular Notes to be redeemed shall be selected, unless otherwise provided
herein, not less than 20 nor more than 60 days prior to the redemption date by
the Trustee from the outstanding Notes not previously called for redemption.

         The Trustee shall promptly notify the Company in writing of the Notes
selected for redemption and, in the case of any Note selected for partial
redemption, the principal amount thereof to be redeemed. Notes and portions of
Notes selected shall be in amounts of $1,000 or whole multiples of $1,000;
except that if all of the Notes of a Holder are to be redeemed, the entire
outstanding amount of Notes held by such Holder, even if not a multiple of
$1,000, shall be redeemed. Except as provided in the preceding sentence,
provisions of this Indenture that apply to Notes called for redemption also
apply to portions of Notes called for redemption.

SECTION 3.03. NOTICE OF REDEMPTION.

         At least 20 days but not more than 60 days before a redemption date,
the Company shall mail or cause to be mailed, by first class mail, a notice of
redemption to each Holder whose Notes are to be redeemed at its registered
address.

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

         (a) the redemption date;

         (b) the redemption price;

         (c) the then current Conversion Price;

         (d) if any Note is being redeemed in part, the portion of the principal
amount of such Note to be redeemed and that, after the redemption date upon
surrender of such Note, a new Note or Notes in principal amount equal to the
unredeemed portion shall be issued upon cancellation of the original Note;

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

         (f) that Notes called for redemption must be surrendered to the Paying
Agent to collect the redemption price;

         (g) that Notes called for redemption must be presented and surrendered
to a Paying Agent to collect the Redemption Price;

         (h) that Holders who wish to convert Notes must surrender such Notes
for conversion no later than the close of business on the Business Day
immediately preceding the Redemption Date and must satisfy the other
requirements in paragraph 8 of the Notes;

         (i) that, unless the Company defaults in making such redemption
payment, interest on Notes called for redemption ceases to accrue on and after
the redemption date;

         (j) the paragraph of the Notes and/or Section of this Indenture
pursuant to which the Notes called for redemption are being redeemed; and





                                       19
<PAGE>   25

         (k) that no representation is made as to the correctness or accuracy of
the CUSIP number, if any, listed in such notice or printed on the Notes.

         At the Company's request, the Trustee shall give the notice of
redemption in the Company's name and at its expense; PROVIDED, HOWEVER, that the
Company shall have delivered to the Trustee, at least 40 days prior to the
redemption date, an Officers' Certificate requesting that the Trustee give such
notice and setting forth the information to be stated in such notice as provided
in the preceding paragraph.

SECTION 3.04. EFFECT OF NOTICE OF REDEMPTION.

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

SECTION 3.05. DEPOSIT OF REDEMPTION PRICE.

         One Business Day prior to the redemption date, the Company shall
deposit with the Trustee or with the Paying Agent money sufficient to pay the
redemption price of and accrued interest on all Notes to be redeemed on that
date. The Trustee or the Paying Agent shall promptly return to the Company any
money deposited with the Trustee or the Paying Agent by the Company in excess of
the amounts necessary to pay the redemption price of, and accrued interest on,
all Notes to be redeemed.

         If the Company complies with the provisions of the preceding paragraph,
on and after the redemption date, interest shall cease to accrue on the Notes or
the portions of Notes called for redemption. If a Note is redeemed on or after
an interest record date but on or prior to the related interest payment date,
then any accrued and unpaid interest shall be paid to the Person in whose name
such Note was registered at the close of business on such record date. If any
Note called for redemption shall not be so paid upon surrender for redemption
because of the failure of the Company to comply with the preceding paragraph,
interest shall be paid on the unpaid principal, from the redemption date until
such principal is paid, and to the extent lawful on any interest not paid on
such unpaid principal, in each case at the rate provided in the Notes and in
Section 6.01 hereof.

SECTION 3.06. NOTES REDEEMED IN PART.

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

SECTION 3.07. PROVISIONAL AND OPTIONAL REDEMPTION.

         (a) The Notes may be redeemed at the election of the Company, as a
whole or in part from time to time, at any time prior to May 20, 2004 (a
"PROVISIONAL REDEMPTION"), upon at least 20 and not more than 60 days' notice by
mail to the Holders of the Notes at a redemption price equal to $1,000 per
$1,000 principal amount of the Notes redeemed plus accrued and unpaid interest,
if any (such amount, together with the Make-Whole Payment described below, the
"PROVISIONAL REDEMPTION PRICE"), to but excluding the date of redemption (the
"PROVISIONAL REDEMPTION DATE") if (1) the Closing Sale Price of the Common Stock
has exceeded 150% of the Conversion Price for at least 20 Trading Days within a
period of any 30 consecutive Trading Days ending on the Trading Day prior to the
date of mailing of the notice of Provisional Redemption (the "NOTICE DATE"), and
(2) a shelf registration statement covering




                                       20
<PAGE>   26

resales of the Notes and the Common Stock issuable upon conversion thereof is
effective and available for use and is expected to remain effective and
available for use for the 30 days following the Provisional Redemption Date
unless registration is no longer required.

         Upon any such Provisional Redemption, the Company, shall make an
additional payment, at its option, in cash or Common Stock or a combination of
cash and Common Stock (the "MAKE-WHOLE PAYMENT") with respect to the Notes
called for redemption to holders on the Notice Date in an amount equal to
$150.00 per $1,000 principal amount of the Notes, less the amount of any
interest actually paid (including, if the Provisional Redemption Date occurs
after a record date but before an interest payment date, any interest paid or to
be paid in connection with such interest payment date) on such Notes prior to
the Provisional Redemption Date. Payments made in Common Stock will be valued at
97% of the average closing sales prices of Common Stock for the five Trading
Days ending on the day prior to the Redemption Date. The Company shall make the
Make-Whole Payment on all Notes called for Provisional Redemption, including
those Notes converted into Common Stock between the Notice Date and the
Provisional Redemption Date.

         (b) Except as set forth in clause (a) of this Section 3.07, the Company
shall not have the option to redeem the Notes pursuant to this Section 3.07
prior to May 20, 2004. Thereafter, the Company shall have the option to redeem
the Notes, in whole or in part, at the redemption prices (expressed as
percentages of principal amount) set forth below plus accrued and unpaid
interest and Additional Interest thereon, if any, to the applicable redemption
date, if redeemed during the periods set forth below:

        Period                                                     Percentage
        ------                                                     ----------

        Beginning May 20, 2004 through May 14, 2005................  101.25%
        Beginning May 15, 2005 and thereafter......................  100.00%

         (c) Any redemption pursuant to this Section 3.07 shall be made pursuant
to the provisions of Section 3.01 through 3.06 hereof.

SECTION 3.08. MANDATORY REDEMPTION.

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

                                   ARTICLE 4.
                                   Conversion

SECTION 4.01. CONVERSION PRIVILEGE.

         A Holder of a Note may convert it into fully paid and nonassessable
shares of Common Stock at any time prior to maturity at the Conversion Price
then in effect, except that, with respect to any Note called for redemption or
submitted or presented for purchase pursuant to Section 6.09, such conversion
right shall terminate at the close of business on the Business Day immediately
preceding the Redemption Date or Change in Control Payment Date, as the case may
be (unless the Company shall default in making the redemption payment or Change
in Control Payment when it becomes due, in which case the conversion right shall
terminate on the date such default is cured and such Note is redeemed or
purchased, as the case may be). The number of shares of Common Stock issuable
upon conversion of a




                                       21
<PAGE>   27

Note is determined by dividing the principal amount of such Note by the
conversion price in effect on the Conversion Date (the "CONVERSION PRICE").

         The initial Conversion Price is stated in Section 8 of the Notes and is
subject to adjustment as provided in this Article 4.

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

         A Note in respect of which a Holder has delivered a Change in Control
Payment Notice pursuant to Section 6.09 exercising the option of such Holder to
require the Company to purchase such Note may be converted only if such Change
in Control Payment Notice is withdrawn by a written notice of withdrawal
delivered to a Paying Agent prior to the close of business on the Business Day
immediately preceding the Change in Control Payment Date in accordance with
Section 6.09.

         A Holder of Notes is not entitled to any rights of a holder of Common
Stock until such Holder has converted its Notes to Common Stock, and only to the
extent such Notes are deemed to have been converted into Common Stock pursuant
to this Article 4.

SECTION 4.02. CONVERSION PROCEDURE.

         To convert a Note, a Holder must satisfy the requirements in Section 8
of the Notes. The date on which the Holder satisfies all of those requirements
is the conversion date (the "CONVERSION DATE"). As soon as practicable after the
Conversion Date, the Company shall deliver to the Holder through the Conversion
Agent a certificate for the number of whole shares of Common Stock issuable upon
the conversion and a check for any fractional share determined pursuant to
Section 4.03 hereof. The Person in whose name the certificate is registered
shall become the stockholder of record on the Conversion Date and, as of such
date, such Person's rights as a Holder shall cease; PROVIDED, HOWEVER, that no
surrender of a Note on any date when the stock transfer books of the Company
shall be closed shall be effective to constitute the Person entitled to receive
the shares of Common Stock upon such conversion as the stockholder of record of
such shares of Common Stock on such date, but such surrender shall be effective
to constitute the Person entitled to receive such shares of Common Stock as the
stockholder of record thereof for all purposes at the close of business on the
next succeeding day on which such stock transfer books are open; PROVIDED
FURTHER, HOWEVER, that such conversion shall be at the Conversion Price in
effect on the date that such Note shall have been surrendered for conversion, as
if the stock transfer books of the Company had not been closed.

         No payment or other adjustment shall be made for accrued interest or
dividends or distributions on any Common Stock issued upon conversion of the
Notes. If any Notes are converted during any period after any record date for
the payment of an installment of interest but before the next interest payment
date, interest for such notes will be paid on the next interest payment date,
notwithstanding such conversion, to the Holders of such Notes. Any Notes that
are, however, delivered to the Company for conversion after any record date but
before the next interest payment date must, except as described in the next
sentence, be accompanied by a payment equal to the interest payable on such
interest payment date on the principal amount of Notes being converted. The
payment to the Company described in the preceding sentence shall not be required
if, during that period between a record date and the next interest payment date,
a conversion occurs on or after the date that the Company has issued a
redemption notice or Change of Control Offer and prior to the date of redemption
stated in such notice or the Change on




                                       22
<PAGE>   28

Control Payment Date, as the case may be. No fractional shares will be issued
upon conversion, but a cash adjustment will be made for any fractional shares.

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

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

SECTION 4.03. FRACTIONAL SHARES.

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

SECTION 4.04. TAXES ON CONVERSION.

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

SECTION 4.05. COMPANY TO PROVIDE STOCK.

         The Company shall at all times reserve and keep available, free from
preemptive rights, out of its authorized but unissued Common Stock, solely for
the purpose of issuance upon conversion of Notes as herein provided, a
sufficient number of shares of Common Stock to permit the conversion of all
outstanding Notes for shares of Common Stock. All shares of Common Stock which
may be issued upon conversion of the Notes shall be duly authorized, validly
issued, fully paid and nonassessable and free of preemptive rights and free of
any lien or adverse claim when so issued.

         The Company will endeavor promptly to comply with all federal and state
securities laws regulating the offer and delivery of shares of Common Stock upon
conversion of Notes, if any, and will list or cause to have quoted such shares
of Common Stock on each national securities exchange or on the Nasdaq National
Market or other over-the-counter market or such other market on which the Common
Stock is then listed or quoted; PROVIDED, HOWEVER, that if rules of such
automated quotation system or exchange permit the Company to defer the listing
of such Common Stock until the first conversion of the Notes into Common Stock
in accordance with the provisions of this Indenture, the Company covenants




                                       23
<PAGE>   29

to list such Common Stock issuable upon conversion of the Notes in accordance
with the requirements of such automated quotation system or exchange at such
time.

SECTION 4.06. ADJUSTMENT OF CONVERSION PRICE.

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

         (a) STOCK SPLIT AND COMBINATIONS. In case the Company, at any time or
from time to time after the issuance date of the Notes (a) subdivides or splits
the outstanding shares of its Common Stock, (b) combines or reclassifies the
outstanding shares of its Common Stock into a smaller number of shares or (c)
issues by reclassification of the shares of its Common Stock any shares of its
capital stock, then the Conversion Price in effect immediately prior to that
event or the record date for that event, whichever is earlier, will be adjusted
so that the holder of any Notes thereafter surrendered for conversion will be
entitled to receive the number of shares of the Company's Common Stock or of its
other securities which the Holder would have owned or have been entitled to
receive after the occurrence of any of the events described above, had those
Notes been surrendered for conversion immediately before the occurrence of that
event or the record date for that event, whichever is earlier;

         (b) STOCK DIVIDENDS IN COMMON STOCK. In case the Company, at any time
or from time to time after the issuance date of the Notes, pays a dividend or
make a distribution in shares of its Common Stock on any class of its capital
stock other than dividends or distributions of shares of Common Stock or other
securities with respect to which adjustments are provided in paragraph (1) above
or with respect to payments of interest or dividend obligations with respect to
a particular series of capital stock in accordance with the terms of such
capital stock, the Conversion Price will be adjusted so that the Holder of each
Note will be entitled to receive, upon conversion of that Note, the number of
shares of the Company's Common Stock determined by multiplying (a) the
Conversion Price by (b) a fraction, the numerator of which will be the number of
shares of Common Stock outstanding and the denominator of which will be the sum
of that number of shares and the total number of shares issued in that dividend
or distribution;

         (c) ISSUANCE OF RIGHTS OR WARRANTS. In case the Company issues to all
holders of its Common Stock rights or warrants entitling those holders for a
period of not more than 60 days to subscribe for or purchase its Common Stock or
securities convertible into its Common Stock at a price per share or conversion
price per share less than the Current Market Price, the Conversion Price in
effect immediately before the close of business on the record date fixed for
determination of shareholders entitled to receive those rights or warrants will
be reduced by multiplying the Conversion Price by a fraction, the numerator of
which is the sum of the number of shares of the Company's Common Stock
outstanding at the close of business on that record date and the number of
shares of Common Stock that the aggregate offering price of the total number of
shares of the Company's Common Stock so offered for subscription or purchase
would purchase at the Current Market Price and the denominator of which is the
sum of the number of shares of Common Stock outstanding at the close of business
on that record date and the number of additional shares of the Company's Common
Stock so offered for subscription or purchase. For purposes of this paragraph
(3), the issuance of rights or warrants to subscribe for or purchase securities
convertible into shares of the Company's Common Stock will be deemed to be the
issuance of rights or warrants to purchase shares of the Company's Common Stock
into which those securities are convertible at an aggregate offering price equal
to the sum of the aggregate offering price of those securities and the minimum
aggregate amount, if any, payable upon conversion of those securities into
shares of the Company's Common Stock. This adjustment will be made successively
whenever any such event occurs;




                                       24
<PAGE>   30

         (d) DISTRIBUTION OF INDEBTEDNESS, SECURITIES OR ASSETS. In case the
Company shall distribute to all or substantially all holders of its Common Stock
any shares of capital stock of the Company (other than Common Stock), evidences
of indebtedness or other non-cash assets (including securities of any person
other than the Company but excluding (1) dividends or distributions paid
exclusively in cash or (2) dividends or distributions referred to in subsection
(b) of this Section 4.06), or shall distribute to all or substantially all
holders of its Common Stock rights or warrants to subscribe for or purchase any
of its securities (excluding those rights and warrants referred to in subsection
(c) of this Section 4.06 and also excluding the distribution of rights to all
holders of Common Stock pursuant to the adoption of a stockholders rights plan
or the detachment of such rights under the terms of such stockholder rights
plan), then in each such case the Conversion Price shall be adjusted so that the
same shall equal the price determined by multiplying the current Conversion
Price by a fraction of which the numerator shall be the current market price per
share (as defined in subsection (g) of this Section 4.06) of the Common Stock on
the record date mentioned below less the fair market value on such record date
(as determined by the Board of Directors, whose determination shall be
conclusive evidence of such fair market value and which shall be evidenced by an
Officers' Certificate delivered to the Trustee) of the portion of the capital
stock, evidences of indebtedness or other non-cash assets so distributed or of
such rights or warrants applicable to one share of Common Stock (determined on
the basis of the number of shares of Common Stock outstanding on the record
date), and of which the denominator shall be the current market price per share
(as defined in subsection (g) of this Section 4.06) of the Common Stock on such
record date. Such adjustment shall be made successively whenever any such
distribution is made and shall become effective immediately after the record
date for the determination of shareholders entitled to receive such
distribution.

         (e) In case the Company shall, by dividend or otherwise, at any time
distribute (a "TRIGGERING DISTRIBUTION") to all or substantially all holders of
its Common Stock cash in an aggregate amount that, together with the aggregate
amount of (A) any cash and the fair market value (as determined by the Board of
Directors, whose determination shall be conclusive evidence thereof and which
shall be evidenced by an Officers' Certificate delivered to the Trustee) of any
other consideration payable in respect of any tender offer by the Company or a
Subsidiary of the Company for Common Stock consummated within the 12 months
preceding the date of payment of the Triggering Distribution and in respect of
which no Conversion Price adjustment pursuant to this Section 4.06 has been made
and (B) all other cash distributions to all or substantially all holders of its
Common Stock made within the 12 months preceding the date of payment of the
Triggering Distribution and in respect of which no Conversion Price adjustment
pursuant to this Section 4.06 has been made, exceeds an amount equal to 10.0% of
the product of the current market price per share of Common Stock (as determined
in accordance with subsection (g) of this Section 4.06) on the Business Day (the
"DETERMINATION DATE") immediately preceding the day on which such Triggering
Distribution is declared by the Company multiplied by the number of shares of
Common Stock outstanding on the Determination Date (excluding shares held in the
treasury of the Company), the Conversion Price shall be reduced so that the same
shall equal the price determined by multiplying such Conversion Price in effect
immediately prior to the Determination Date by a fraction of which the numerator
shall be the current market price per share of the Common Stock (as determined
in accordance with subsection (g) of this Section 4.06) on the Determination
Date less the sum of the aggregate amount of cash and the aggregate fair market
value (determined as aforesaid in this Section 4.06(d)) of any such other
consideration so distributed, paid or payable within such 12 months (including,
without limitation, the Triggering Distribution) applicable to one share of
Common Stock (determined on the basis of the number of shares of Common Stock
outstanding on the Determination Date) and the denominator shall be such current
market price per share of the Common Stock (as determined in accordance with
subsection (g) of this Section 4.06) on the



                                       25
<PAGE>   31

Determination Date, such reduction to become effective immediately prior to the
opening of business on the day following the date on which the Triggering
Distribution is paid.

         (f) In case any tender offer made by the Company or any of its
Subsidiaries for Common Stock shall expire and such tender offer (as amended
upon the expiration thereof) shall involve the payment of aggregate
consideration in an amount (determined as the sum of the aggregate amount of
cash consideration and the aggregate fair market value (as determined by the
Board of Directors, whose determination shall be conclusive evidence thereof and
which shall be evidenced by an Officers' Certificate delivered to the Trustee
thereof) of any other consideration) that, together with the aggregate amount of
(A) any cash and the fair market value (as determined by the Board of Directors,
whose determination shall be conclusive evidence thereof and which shall be
evidenced by an Officers' Certificate delivered to the Trustee) of any other
consideration payable in respect of any other tender offers by the Company or
any Subsidiary of the Company for Common Stock consummated within the 12 months
preceding the date of the Expiration Date (as defined below) and in respect of
which no Conversion Price adjustment pursuant to this Section 4.06 has been made
and (B) all cash distributions to all or substantially all holders of its Common
Stock made within the 12 months preceding the Expiration Date and in respect of
which no Conversion Price adjustment pursuant to this Section 4.06 has been
made, exceeds an amount equal to 10.0% of the product of the current market
price per share of Common Stock (as determined in accordance with subsection (g)
of this Section 4.06) as of the last date (the "EXPIRATION DATE") tenders could
have been made pursuant to such tender offer (as it may be amended) (the last
time at which such tenders could have been made on the Expiration Date is
hereinafter sometimes called the "EXPIRATION TIME") multiplied by the number of
shares of Common Stock outstanding (including tendered shares but excluding any
shares held in the treasury of the Company) at the Expiration Time, then,
immediately prior to the opening of business on the day after the Expiration
Date, the Conversion Price shall be reduced so that the same shall equal the
price determined by multiplying the Conversion Price in effect immediately prior
to close of business on the Expiration Date by a fraction of which the numerator
shall be the product of the number of shares of Common Stock outstanding
(including tendered shares but excluding any shares held in the treasury of the
Company) at the Expiration Time multiplied by the current market price per share
of the Common Stock (as determined in accordance with subsection (g) of this
Section 4.06) on the Trading Day next succeeding the Expiration Date and the
denominator shall be the sum of (x) the aggregate consideration (determined as
aforesaid) payable to stockholders based on the acceptance (up to any maximum
specified in the terms of the tender offer) of all shares validly tendered and
not withdrawn as of the Expiration Time (the shares deemed so accepted, up to
any such maximum, being referred to as the "PURCHASED SHARES") and (y) the
product of the number of shares of Common Stock outstanding (less any Purchased
Shares and excluding any shares held in the treasury of the Company) at the
Expiration Time and the current market price per share of Common Stock (as
determined in accordance with subsection (g) of this Section 4.06) on the
Trading Day next succeeding the Expiration Date, such reduction to become
effective immediately prior to the opening of business on the day following the
Expiration Date. In the event that the Company is obligated to purchase shares
pursuant to any such tender offer, but the Company is permanently prevented by
applicable law from effecting any or all such purchases or any or all such
purchases are rescinded, the Conversion Price shall again be adjusted to be the
Conversion Price which would have been in effect based upon the number of shares
actually purchased. If the application of this Section 4.06(f) to any tender
offer would result in an increase in the Conversion Price, no adjustment shall
be made for such tender offer under this Section 4.06(f).

         For purposes of this Section 4.06(e), the term "tender offer" shall
mean and include both tender offers and exchange offers, all references to
"purchases" of shares in tender offers (and all similar references) shall mean
and include both the purchase of shares in tender offers and the acquisition of





                                       26
<PAGE>   32

shares pursuant to exchange offers, and all references to "tendered shares" (and
all similar references) shall mean and include shares tendered in both tender
offers and exchange offers.

         (g) For the purpose of any computation under subsections (b), (c), (d)
and (e) of this Section 4.06, the current market price per share of Common Stock
on any date shall be deemed to be the average of the daily Closing Sale Prices
for the 30 consecutive Trading Days commencing 45 Trading Days before (i) the
Determination Date or the Expiration Date, as the case may be, with respect to
distributions or tender offers under subsections (d) and (e) of this Section
4.06 or (ii) the record date with respect to distributions, issuances or other
events requiring such computation under subsection (c), (d) or (e) of this
Section 4.06. If no such prices are available, the current market price per
share shall be the fair value of share of Common Stock as determined by the
Board of Directors (which shall be evidenced by an Officers' Certificate
delivered to the Trustee).

         (h) If any distribution in respect of which an adjustment to the
Conversion Price is required to be made as of the record date or Determination
Date or Expiration Date therefor is not thereafter made or paid by the Company
for any reason, the Conversion Price shall be readjusted to the Conversion Price
which would then be in effect if such record date had not been fixed or such
effective date or Determination Date or Expiration Date had not occurred.

SECTION 4.07. NO ADJUSTMENT.

         No adjustment in the Conversion Price shall be required until
cumulative adjustments amount to 1% or more of the Conversion Price as last
adjusted; PROVIDED, HOWEVER, that any adjustments which by reason of this
Section 4.07 are not required to be made shall be carried forward and taken into
account in any subsequent adjustment. All calculations under this Article 4
shall be made to the nearest cent or to the nearest one-hundredth of a share, as
the case may be. No adjustment need be made for rights to purchase Common Stock
pursuant to a Company plan for reinvestment of dividends or interest. No
adjustment need be made for a change in the par value or no par value of the
Common Stock.

SECTION 4.08. OTHER ADJUSTMENTS.

         (a) In the event that, as a result of an adjustment made pursuant to
Section 4.06 hereof, the Holder of any Note thereafter surrendered for
conversion shall become entitled to receive any shares of Capital Stock of the
Company other than shares of its Common Stock, thereafter the Conversion Price
of such other shares so receivable upon conversion of any Note shall be subject
to adjustment from time to time in a manner and on terms as nearly equivalent as
practicable to the provisions with respect to Common Stock contained in this
Article 4.

         (b) In the event that shares of Common Stock are not delivered after
the expiration of any of the rights or warrants referred to in Section 4.06(b)
and Section 4.06(c) hereof, the Conversion Price shall be readjusted to the
Conversion Price which would otherwise be in effect had the adjustment 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.

SECTION 4.09. ADJUSTMENTS FOR TAX PURPOSES.

         The Company may make such reductions in the Conversion Price, in
addition to those required by Section 4.06 hereof, as it determines in its
discretion to be advisable in order that any stock dividend, subdivision of
shares, distribution or rights to purchase stock or securities or distribution
of securities




                                       27
<PAGE>   33

convertible into or exchangeable for stock made by the Company to its
stockholders will not be taxable to the recipients thereof.

SECTION 4.10. NOTICE OF ADJUSTMENT.

         Whenever the Conversion Price is adjusted, the Company shall promptly
mail to Holders at the addresses appearing on the Registrar's books a notice of
the adjustment and file with the Trustee an Officers' Certificate briefly
stating the facts requiring the adjustment and the manner of computing it. The
certificate shall be conclusive evidence of the correctness of such adjustment.
Unless and until a Trust Officer of the Trustee shall receive written notice of
an adjustment of the Conversion Price, the Trustee may assume without inquiry
that the Conversion Price has not been adjusted and that the last Conversion
Price of which it has knowledge remains in effect.

SECTION 4.11. NOTICE OF CERTAIN TRANSACTIONS.

         In the event that:

         (1) the Company takes any action which would require an adjustment in
the Conversion Price;

         (2) the Company takes any action that would require a supplemental
indenture pursuant to Section 4.12; or

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

the Company shall mail to Holders at the addresses appearing on the Registrar's
books and the Trustee a notice stating the proposed record or effective date, as
the case may be, to permit a Holder of a Note to convert such Note into shares
of Common Stock prior to the record date for or the effective date of the
transaction in order to receive the rights, warrants, securities or assets which
a holder of shares of Common Stock on that date may receive. The Company shall
mail the notice at least 15 days before such date; however, failure to mail such
notice or any defect therein shall not affect the validity of any transaction
referred to in clause (1), (2) or (3) of this Section 4.11.

SECTION 4.12. EFFECT OF RECLASSIFICATIONS, CONSOLIDATIONS, MERGERS OR SALES ON
              CONVERSION PRIVILEGE.

         If any of the following shall occur, namely: (i) any reclassification
or change of outstanding shares of Common Stock issuable upon conversion of
Notes (other than a change in par value, or from par value to no par value, or
from no par value to par value, or as a result of a subdivision or combination
or as a result of a reincorporation of the Company in another jurisdiction),
(ii) any consolidation or merger to which the Company is a party other than a
merger in which the Company is the continuing corporation and which does not
result in any reclassification of, or change (other than a change in name, or
par value, or from par value to no par value, or from no par value to par value
or as a result of a subdivision or combination) in, outstanding shares of Common
Stock or (iii) any sale or conveyance of all or substantially all of the
property or business of the Company as an entirety, then the Company, or such
successor or purchasing corporation, as the case may be, shall, as a condition
precedent to such reclassification, change, consolidation, merger, sale or
conveyance, execute and deliver to the Trustee a supplemental indenture in form
reasonably satisfactory to the Trustee providing that the Holder of each Note
then outstanding shall have the right to convert such Note into the kind and
amount of shares of stock and other securities and property (including cash)
receivable upon such reclassification, change, consolidation, merger, sale or
conveyance by a Holder of the number of shares of Common Stock




                                       28
<PAGE>   34

deliverable upon conversion of such Note immediately prior to such
reclassification, change, consolidation, merger, sale or conveyance. In the
event that the shares of Common Stock are exchanged or substituted for other
securities in connection with any such reclassification, change, consolidation,
merger, sale or conveyance, such supplemental indenture shall provide for
adjustments of the Conversion Price which shall be as nearly equivalent as may
be practicable to the adjustments of the Conversion Price provided for in this
Article 4. If, in the case of any such consolidation, merger, sale or
conveyance, the stock or other securities and property (including cash)
receivable thereupon by a Holder of Common Stock includes shares of stock or
other securities and property of a corporation other than the successor or
purchasing corporation, as the case may be, in such consolidation, merger, sale
or conveyance, then such supplemental indenture shall also be executed by such
other corporation and shall contain such additional provisions to protect the
interests of the Holders of the Notes as the Board of Directors of the Company
shall reasonably consider necessary by reason of the foregoing. The provision of
this Section 4.12 shall similarly apply to successive consolidations, mergers,
sales or conveyances.

         In the event the Company shall execute a supplemental indenture
pursuant to this Section 4.12, the Company shall promptly file with the Trustee
an Officers' Certificate briefly stating the reasons therefor, the kind or
amount of shares of stock or securities or property (including cash) receivable
by Holders of the Notes upon the conversion of their Notes after any such
reclassification, change, consolidation, merger, sale or conveyance and any
adjustment to be made with respect thereto.

SECTION 4.13. TRUSTEE'S DISCLAIMER.

         The Trustee has no duty to determine when an adjustment under this
Article 4 should be made, how it should be made or what such adjustment should
be, but may accept as conclusive evidence of the correctness of any such
adjustment, and shall be protected in relying upon, the Officers' Certificate
with respect thereto which the Company is obligated to file with the Trustee
pursuant to Section 4.10 hereof. The Trustee makes no representation as to the
validity or value of any securities or assets issued upon conversion of Notes,
and the Trustee shall not be responsible for the Company's failure to comply
with any provisions of this Article 4.

         The Trustee shall not be under any responsibility to determine the
correctness of any provisions contained in any supplemental indenture executed
pursuant to Section 4.12, but may accept as conclusive evidence of the
correctness thereof, and shall be protected in relying upon, the Officers'
Certificate with respect thereto which the Company is obligated to file with the
Trustee pursuant to Section 4.12 hereof.

SECTION 4.14. VOLUNTARY REDUCTION.

         The Company from time to time may reduce the Conversion Price by any
amount for any period of time if the period is at least 20 days and if the
reduction is irrevocable during the period if the Board of Directors determines
that such reduction would be in the best interest of the Company and the Company
provides 15 days prior notice of any reduction in the Conversion Price;
provided, however, that in no event may the Company reduce the Conversion Price
to be less than the par value of a share of Common Stock.




                                       29
<PAGE>   35

                                   ARTICLE 5.
                                  SUBORDINATION

SECTION 5.01. AGREEMENT TO SUBORDINATE.

         The Company agrees, and each Holder by accepting a Note agrees, that
the Indebtedness evidenced by the Notes (including the principal of, premium, if
any, and interest (including Additional Interest, if any) on all the Notes and
the redemption price and Make-Whole Payment, if any, with respect to any Notes
being called for redemption and the Change in Control Payment with respect to
all Notes subject to purchase pursuant to Section 6.09 hereof) is subordinated
in right of payment, to the extent and in the manner provided in this Article 5,
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
provision of this Section 5 shall prevent the occurrence of any Default or Event
of Default.

SECTION 5.02. LIQUIDATION; DISSOLUTION; BANKRUPTCY.

         Upon any distribution to creditors of the Company in a liquidation or
dissolution of the Company or in a bankruptcy, reorganization, insolvency,
receivership or similar proceeding relating to the Company or its property, in
an assignment for the benefit of creditors or any marshaling of the Company's
assets and liabilities:

                  (i) holders of Senior Indebtedness shall be entitled to
         receive payment in full of all Obligations due in respect of such
         Senior Indebtedness (including interest after the commencement of any
         such proceeding at the rate specified in the applicable Senior
         Indebtedness) before Holders of the Notes shall be entitled to receive
         any payment with respect to the Notes (except that Holders may receive
         Permitted Junior Securities); and

                  (ii) until all Obligations with respect to Senior Indebtedness
         (as provided in clause (i) above) are paid in full, any distribution to
         which Holders would be entitled but for this Article 5 shall be made to
         holders of Senior Indebtedness (except that Holders of Notes may
         receive Permitted Junior Securities), as their interests may appear.

SECTION 5.03. DEFAULT ON DESIGNATED SENIOR INDEBTEDNESS.

         (a) The Company may not make any payment or distribution to the Trustee
or any Holder in respect of Obligations with respect to the Notes and may not
acquire from the Trustee or any Holder any Notes for cash or property (other
than Permitted Junior Securities) until all principal and other Obligations with
respect to the Senior Indebtedness have been paid in full if:

                  (i) a default in the payment of any principal or other
         Obligations with respect to Designated Senior Indebtedness occurs and
         is continuing beyond any applicable grace period in the agreement,
         indenture or other document governing such Designated Senior
         Indebtedness; or

                  (ii) a default, other than a payment default, on Designated
         Senior Indebtedness occurs and is continuing that then permits holders
         of the Designated Senior Indebtedness to accelerate its maturity and
         the Trustee receives a notice of the default (a "PAYMENT BLOCKAGE
         NOTICE") from a Person who may give it pursuant to Section 5.12 hereof.
         If the Trustee receives any such Payment Blockage Notice, no subsequent
         Payment Blockage Notice shall be effective for purposes of this Section
         unless and until (A) at least 360 days shall have elapsed since




                                       30
<PAGE>   36

         the issuance of the immediately prior Payment Blockage Notice and (B)
         all scheduled payments of principal, premium, if any, and interest on
         the Notes that have come due have been paid in full in cash. No
         nonpayment default that existed or was continuing on the date of
         delivery of any Payment Blockage Notice to the Trustee shall be, or be
         made, the basis for a subsequent Payment Blockage Notice unless such
         default shall have been waived for a period of not less than 180 days.

         (b) The Company may and shall resume payments on and distributions in
respect of the Notes and may acquire them upon the earlier of:

                  (i) the date upon which the Trustee receives notice from the
         Company that the default is cured or waived or ceases to exist, or

                  (ii) in the case of a default referred to in clause (ii) of
         Section 5.04(a) hereof, 179 days pass after the Payment Blockage Notice
         is received if the maturity of such Designated Senior Indebtedness has
         not been accelerated,

if this Article 5 otherwise permits the payment, distribution or acquisition at
the time of such payment or acquisition.

SECTION 5.04. ACCELERATION OF NOTES.

         If payment of the Notes is accelerated because of an Event of Default,
the Company shall promptly notify holders of Senior Indebtedness of the
acceleration.

SECTION 5.05. WHEN DISTRIBUTION MUST BE PAID OVER.

         In the event that the Trustee or any Holder receives any payment of any
Obligations or distribution of assets of the Company of any kind or character
(other than Permitted Junior Securities pursuant to Section 5 hereof),whether in
cash, property or securities (including, without limitation, by way of setoff or
otherwise) with respect to the Notes at a time when the Trustee or such Holder,
as applicable, has actual knowledge that such payment is prohibited by Section
5.03 hereof, such payment shall be held by the Trustee or such Holder, in trust
for the benefit of, and shall be paid forthwith over and delivered, upon written
request, to, the holders of Senior Indebtedness as their interests may appear or
their Representative under the indenture or other agreement (if any) pursuant to
which Senior Indebtedness may have been issued, as their respective interests
may appear, for application to the payment of all Obligations with respect to
Senior Indebtedness remaining unpaid to the extent necessary to pay such
Obligations in full in accordance with their terms, after giving effect to any
concurrent payment or distribution to or for the holders of Senior Indebtedness.

         With respect to the holders of Senior Indebtedness, the Trustee
undertakes to perform only such obligations on the part of the Trustee as are
specifically set forth in this Article 5, and no implied covenants or
obligations with respect to the holders of Senior Indebtedness shall be read
into this Indenture against the Trustee. The Trustee shall not be deemed to owe
any fiduciary duty to the holders of Senior Indebtedness, and shall not be
liable to any such holders if the Trustee shall pay over or distribute to or on
behalf of Holders or the Company or any other Person money or assets to which
any holders of Senior Indebtedness shall be entitled by virtue of this Article
5, except if such payment is made as a result of the willful misconduct or gross
negligence of the Trustee.




                                       31
<PAGE>   37

SECTION 5.06. NOTICE BY COMPANY.

         The Company shall promptly notify the Trustee and the Paying Agent of
any facts known to the Company that would cause a payment of any Obligations
with respect to the Notes to violate this Article 5, but failure to give such
notice shall not affect the subordination of the Notes to the Senior
Indebtedness as provided in this Article 5.

SECTION 5.07. SUBROGATION.

         After all Senior Indebtedness is paid in full in cash or other payment
satisfactory to the holders of the Senior Indebtedness and until the Notes are
paid in full, Holders of Notes shall be subrogated (equally and ratably with all
other Indebtedness PARI PASSU with the Notes and entitled to similar rights of
subrogation) to the rights of holders of Senior Indebtedness to receive payments
or distributions applicable to Senior Indebtedness to the extent that payments
or distributions otherwise payable to the Holders of Notes have been applied to
the payment of Senior Indebtedness. A distribution made under this Article 5 to
holders of Senior Indebtedness that otherwise would have been made to Holders of
Notes (whether by the Company, any Holder, the Trustee or otherwise) is not, as
between the Company and Holders, a payment by the Company on the Notes.

SECTION 5.08. RELATIVE RIGHTS.

         This Article 5 defines the relative rights of Holders of Notes and
holders of Senior Indebtedness. Nothing in this Indenture shall:

                  (i) impair, as between the Company and Holders of Notes, the
         obligation of the Company, which is absolute and unconditional, to pay
         principal of, premium, if any, and interest (including Additional
         Interest) on the Notes in accordance with their terms;

                  (ii) affect the relative rights of Holders of Notes and
         creditors of the Company other than their rights in relation to holders
         of Senior Indebtedness; or

                  (iii) prevent the Trustee or any Holder of Notes from
         exercising its available remedies upon a Default or Event of Default,
         subject to the rights of holders and owners of Senior Indebtedness to
         receive distributions and payments otherwise payable to Holders of
         Notes.

         If the Company fails because of this Article 5 to pay principal of,
premium, if any, or interest (including Additional Interest) on a Note on the
due date, the failure is still a Default or Event of Default.

SECTION 5.09. SUBORDINATION MAY NOT BE IMPAIRED BY COMPANY.

         No right of any holder of Senior Indebtedness to enforce the
subordination of the Indebtedness evidenced by the Notes shall be impaired by
any act or failure to act by the Company or any Holder or by the failure of the
Company or any Holder to comply with this Indenture.

SECTION 5.10. DISTRIBUTION OR NOTICE TO REPRESENTATIVE.

         Whenever a distribution is to be made or a notice given to holders of
Senior Indebtedness, the distribution may be made and the notice given to their
Representative.




                                       32
<PAGE>   38

         Upon any payment or distribution of assets of the Company referred to
in this Article 5, the Trustee and the Holders of Notes shall be entitled to
rely upon any order or decree made by any court of competent jurisdiction or
upon any certificate of such Representative or of the liquidating trustee or
agent or other Person making any distribution to the Trustee or to the Holders
of Notes for the purpose of ascertaining the Persons entitled to participate in
such distribution, the holders of the Senior Indebtedness 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 5.

SECTION 5.11. RIGHTS OF TRUSTEE AND PAYING AGENT.

         Notwithstanding the provisions of this Article 5 or any other provision
of this Indenture, the Trustee shall not be charged with knowledge of the
existence of any facts that would prohibit the making of any payment or
distribution by the Trustee, and the Trustee and the Paying Agent may continue
to make payments on the Notes, unless the Trustee shall have received at its
Corporate Trust Office at least five Business Days prior to the date of such
payment written notice of facts that would cause the payment of any Obligations
with respect to the Notes to violate this Article 5. Only the Company or a
Representative may give the notice. Nothing in this Article 5 shall impair the
claims of, or payments to, the Trustee under or pursuant to Section 9.07 hereof.

         The Trustee in its individual or any other capacity may hold Senior
Indebtedness with the same rights it would have if it were not Trustee. Any
Agent may do the same with like rights.

SECTION 5.12. AUTHORIZATION TO EFFECT SUBORDINATION.

         Each Holder of Notes, by the Holder's acceptance thereof, authorizes
and directs the Trustee on such Holder's behalf to take such action as may be
necessary or appropriate to effectuate the subordination as provided in this
Article 5, and appoints the Trustee to act as such Holder's attorney-in-fact for
any and all such purposes. If the Trustee does not file a proper proof of claim
or proof of debt in the form required in any proceeding referred to in Section
8.09 hereof at least 30 days before the expiration of the time to file such
claim, the holders of any Designated Senior Indebtedness are hereby authorized
to file an appropriate claim for and on behalf of the Holders of the Notes.

SECTION 5.13. AMENDMENTS.

         The provisions of this Article 5 shall not be amended or modified
without the written consent of the holders of all Senior Indebtedness.

SECTION 5.14. AGREEMENT TO SUBORDINATE UNAFFECTED.

         The provisions of this Article 5 shall remain in full force and effect
irrespective of (a) any amendment, modification, or supplement of, or any waiver
or consent to, any of the terms of the Senior Indebtedness or the agreement or
instrument governing the Senior Indebtedness, (b) the release or non-perfection
of any collateral securing the Senior Indebtedness or (c) the manner of sale or
other disposition of the collateral securing the Senior Indebtedness or the
application of the proceeds upon such sale.

SECTION 5.15. CERTAIN CONVERSIONS DEEMED PAYMENT.

         For the purposes of this Article 5 only, (1) the issuance and delivery
of Permitted Junior Securities upon conversion of Notes in accordance with
Article 4 shall not be deemed to constitute a




                                       33
<PAGE>   39

payment or distribution on account of the principal of, or premium, if any, or
interest (including Additional Interest) on the Notes or on account of the
purchase or other acquisition of Notes, and (2) the payment, issuance or
delivery of cash (except in satisfaction of fractional shares pursuant to
Section 4.03), property or securities (other than Permitted Junior Securities)
upon conversion of a Note shall be deemed to constitute payment on account of
the principal of such Note. Nothing contained in this Article 5 or elsewhere in
this Indenture or in the Notes is intended to or shall impair, as among the
Company, its creditors other than holders of Senior Indebtedness and the
Holders, the right, which is absolute and unconditional, of the Holder of any
Note to convert such Note in accordance with Article 4.

                                   ARTICLE 6.
                                    COVENANTS

SECTION 6.01. PAYMENT OF NOTES.

         The Company shall pay or cause to be paid the principal of, premium, if
any, and interest on the Notes on the dates and in the manner provided in the
Notes. Principal, premium, if any, and interest shall be considered paid on the
date due if the Paying Agent, if other than the Company or a Subsidiary thereof,
holds as of 10:00 a.m. Eastern Time on the due date money deposited by the
Company in immediately available funds and designated for and sufficient to pay
all principal, premium, if any, and interest then due. The Company shall pay all
Additional Interest, if any, in the same manner on the dates and in the amounts
set forth in the Registration Rights Agreement.

         The Company shall pay interest (including post-petition interest in any
proceeding under any Bankruptcy Law) on overdue principal at the rate borne by
the Notes to the extent lawful; it shall pay interest (including post-petition
interest in any proceeding under any Bankruptcy Law) on overdue installments of
interest and Additional Interest (without regard to any applicable grace period)
at the same rate to the extent lawful.

SECTION 6.02. MAINTENANCE OF OFFICE OR AGENCY.

         The Company shall maintain in the Borough of Manhattan, the City of New
York, a Paying Agent, Conversion Agent, Registrar and an office or agency (which
may be an office of the Trustee or an affiliate of the Trustee, Registrar or
co-registrar) where Notes may be surrendered for registration of transfer or for
exchange and where notices and demands to or upon the Company in respect of the
Notes and this Indenture may be served. The Company shall give prompt written
notice to the Trustee of the location, and any change in the location, of such
office or agency. If at any time the Company shall fail to maintain any such
required office or agency or shall fail to furnish the Trustee with the address
thereof, such presentations, surrenders, notices and demands may be made or
served at the Corporate Trust Office of the Trustee.

         The Company may also from time to time designate one or more other
offices or agencies where the Notes may be presented or surrendered for any or
all such purposes and may from time to time rescind such designations; PROVIDED,
HOWEVER, that no such designation or rescission shall in any manner relieve the
Company of its obligation to maintain an office or agency in the Borough of
Manhattan, the City of New York for such purposes. The Company shall give prompt
written notice to the Trustee of any such designation or rescission and of any
change in the location of any such other office or agency.

         The Company hereby designates the Corporate Trust Office of the Trustee
as one such office or agency of the Company in accordance with Section 2.03.





                                       34
<PAGE>   40

SECTION 6.03. REPORTS.

         Whether or not required by the rules and regulations of the SEC, so
long as any Notes are outstanding, the Company shall furnish to the Holders of
Notes (i) all quarterly and annual financial information that would be required
to be contained in a filing with the SEC on Forms 10-Q and 10-K if the Company
were required to file such forms, including a "Management's Discussion and
Analysis of Financial Condition and Results of Operations" and, with respect to
the annual information only, a report thereon by the Company's certified
independent accountants and (ii) all current reports that would be required to
be filed with the SEC on Form 8-K if the Company were required to file such
reports, in each case, within the time periods specified in the SEC's rules and
regulations; provided, that if the Company files the reports required by this
Section 6.03 with the SEC and such reports are publicly available, it shall be
deemed to have satisfied its obligation to furnish such reports to the Holders
pursuant to this Section 6.03. The Company shall at all times comply with TIA
ss. 314(a).

SECTION 6.04. 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 Notes or any Common Stock
issued upon conversion thereof which continue to be Restricted Notes in
connection with any sale thereof and any prospective purchaser of Notes 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 Notes or such Common Stock and it will
take such further action as any Holder or beneficial holder of such Notes 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 Notes 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 Notes or such
Common Stock, the Company will deliver to such Holder a written statement as to
whether it has complied with such requirements.

SECTION 6.05. COMPLIANCE CERTIFICATE.

         (a) The Company shall deliver to the Trustee, within 90 days after the
end of each fiscal year, an Officers' Certificate stating that a review of the
activities of the Company and its Subsidiaries during the preceding fiscal year
has been made under the supervision of the signing Officers with a view to
determining whether the Company has kept, observed, performed and fulfilled its
obligations under this Indenture, and further stating, as to each such Officer
signing such certificate, that to the best of his or her knowledge the Company
has kept, observed, performed and fulfilled each and every covenant contained in
this Indenture and is not in default in the performance or observance of any of
the terms, provisions and conditions of this Indenture (or, if a Default or
Event of Default shall have occurred, describing all such Defaults or Events of
Default of which he or she may have knowledge and what action the Company is
taking or proposes to take with respect thereto) and that to the best of his or
her knowledge no event has occurred and remains in existence by reason of which
payments on account of the principal of or interest, if any, on the Notes is
prohibited or if such event has occurred, a description of the event and what
action the Company is taking or proposes to take with respect thereto.

         (b) The Company shall, so long as any of the Notes are outstanding,
deliver to the Trustee, forthwith upon any Officer becoming aware of any Default
or Event of Default, an Officers' Certificate




                                       35
<PAGE>   41

specifying such Default or Event of Default and what action the Company is
taking or proposes to take with respect thereto.

SECTION 6.06. TAXES.

         The Company shall pay, and shall cause each of its Subsidiaries to pay,
prior to delinquency, all material taxes, assessments, and governmental levies
except such as are contested in good faith and by appropriate proceedings or
where the failure to effect such payment is not adverse in any material respect
to the Holders of the Notes.

SECTION 6.07. 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 wherever
enacted, now or at any time hereafter in force, that may affect the covenants or
the performance of this Indenture; and the Company (to the extent that it may
lawfully do so) hereby expressly waives all benefit or advantage of any such
law, and covenants that it shall not, by resort to any such law, hinder, delay
or impede the execution of any power herein granted to the Trustee, but shall
suffer and permit the execution of every such power as though no such law has
been enacted.

SECTION 6.08. CORPORATE EXISTENCE.

         Subject to Article 7 hereof, the Company shall do or cause to be done
all things necessary to preserve and keep in full force and effect (i) its
corporate existence, and the corporate, partnership or other existence of each
of its Subsidiaries, in accordance with the respective organizational documents
(as the same may be amended from time to time) of the Company or any such
Subsidiary and (ii) the rights (charter and statutory), licenses and franchises
of the Company and its Subsidiaries; PROVIDED, HOWEVER, that the Company shall
not be required to preserve any such right, license or franchise, or the
corporate, partnership or other existence of any of its Subsidiaries, if the
Board of Directors shall determine that the preservation thereof is no longer
desirable in the conduct of the business of the Company and its Subsidiaries,
taken as a whole, and that the loss thereof is not adverse in any material
respect to the Holders of the Notes.

SECTION 6.09. OFFER TO REPURCHASE UPON CHANGE OF CONTROL.

         (a) Upon the occurrence of a Change of Control, the Company shall make
an offer (a "CHANGE OF CONTROL OFFER") to each Holder to repurchase all or any
part (equal to $1,000 or an integral multiple thereof) of each Holder's Notes at
a purchase price equal to 100% of the aggregate principal amount thereof plus
accrued and unpaid interest and Additional Interest thereon, if any, to, but
excluding, the date of purchase (the "CHANGE OF CONTROL PAYMENT"). Within 10
business days following any Change of Control, the Company shall mail a notice
to each Holder stating: (1) that the Change of Control Offer is being made
pursuant to this Section 6.09 and that all Notes tendered will be accepted for
payment; (2) the purchase price and the purchase date, which shall be 30
business days after the occurrence of a Change of Control (the "CHANGE OF
CONTROL PAYMENT DATE"); (3) that any Note not tendered will continue to accrue
interest; (4) the name and address of each Paying Agent and Conversion Agent,
(5) the Conversion Price and any adjustments thereto, (6) that Notes as to which
a Change in Control Payment Notice has been given may be converted into Common
Stock pursuant to Article 4 of this Indenture only to the extent that the Change
in Control Payment Notice has been withdrawn in accordance with the terms of
this Indenture, (7) that, unless the Company defaults in the payment of the





                                       36
<PAGE>   42

Change of Control Payment, all Notes accepted for payment pursuant to the Change
of Control Offer shall cease to accrue interest after the Change of Control
Payment Date; (8) that Holders electing to have any Notes purchased pursuant to
a Change of Control Offer will be required to surrender the Notes, with the form
entitled "Option of Holder to Elect Purchase" on the reverse of the Notes
completed, to the Paying Agent at the address specified in the notice prior to
the close of business on the Business Day preceding the Change of Control
Payment Date; (9) that Holders will be entitled to withdraw their election if
the Paying Agent receives, not later than the close of business on the Business
Day preceding the Change of Control Payment Date, a telegram, telex, facsimile
transmission, letter or any other written form setting forth the name of the
Holder, the principal amount of Notes delivered for purchase, and a statement
that such Holder is withdrawing his election to have the Notes purchased; and
(10) that Holders whose Notes are being purchased only in part will be issued
new Notes equal in principal amount to the unpurchased portion of the Notes
surrendered, which unpurchased portion must be equal to $1,000 in principal
amount or an integral multiple thereof. The Company shall comply with the
requirements of Rule 13e-4 and Rule 14e-1 under the Exchange Act and any other
securities laws and regulations thereunder to the extent such laws and
regulations are applicable in connection with the repurchase of Notes in
connection with a Change of Control.

         A "Change in Control" shall be deemed to have occurred if any of the
following occurs after the date hereof:

                  (i) any "person" or "group" (as such terms are defined below)
         is or becomes the "beneficial owner" (as defined below), directly or
         indirectly (other than as a direct result of repurchases of stock by
         the Company), of shares of Voting Stock of the Company representing 50%
         or more of the total voting power of all outstanding classes of Voting
         Stock of the Company or such person or group (other than the
         "management group") has the power, directly or indirectly, to elect a
         majority of the members of the Board of Directors of the Company;
         provided, that Voting Stock acquired in an exempt transaction shall not
         constitute a Change in Control, or

                  (ii) the Company consolidates with, or merges with or into,
         another Person or the Company sells, assigns, conveys, transfers,
         leases or otherwise disposes of all or substantially all of the assets
         of the Company, or any Person consolidates with, or merges with or
         into, the Company, in any such event other than (a) pursuant to a
         transaction in which the Persons that "beneficially owned" (as defined
         below), directly or indirectly, shares of Voting Stock of the Company
         immediately prior to such transaction "beneficially own" (as defined
         below), directly or indirectly, shares of Voting Stock of the Company
         representing at least a majority of the total voting power of all
         outstanding classes of Voting Stock of the surviving or transferee
         Person or (b) an exempt transaction; or

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

         For the purpose of the definition of "Change in Control", (i) "person"
and "group" have the meanings given such terms under Section 13(d) and 14(d) of
the Exchange Act or any successor provision to either of the foregoing, and the
term "group" includes any group acting for the purpose of acquiring, holding or
disposing of securities within the meaning of Rule 13d-5(b)(1) under the
Exchange Act (or any successor provision thereto), (ii) a "beneficial owner"
shall be determined in accordance with Rule 13d-3 under the Exchange Act, as in
effect on the date of this Indenture, except that the number of shares of Voting
Stock of the Company shall be deemed to include, in addition to all outstanding
shares of Voting Stock of the Company and Unissued Shares deemed to be held by
the "person" or "group" (as




                                       37
<PAGE>   43

such terms are defined above) or other Person with respect to which the Change
in Control determination is being made, all Unissued Shares deemed to be held by
all other Persons, and (iii) the terms "beneficially owned" and "beneficially
own" shall have meanings correlative to that of "beneficial owner". The term
"Unissued Shares" means shares of Voting Stock not outstanding that are subject
to options, warrants, rights to purchase or conversion privileges exercisable
within 60 days of the date of determination of a Change in Control. The term
"exempt transaction" means any purchase from the Company of equity interests in
the Company by the management group; provided that the management group does not
collectively beneficially own more than 65% of the total Voting Stock of all
outstanding classes of Voting Stock of the Company following such purchase. The
term "management group" means any of Thomas Russell, The AER 1997 Trust, Robert
Louis-Dreyfus, Gallium Enterprises, Inc. and Reuben Richards.

         Notwithstanding anything to the contrary set forth in this Section
6.09, a Change in Control will not be deemed to have occurred if either:

                  (i) the Closing Sale Price of the Common Stock for any five
         Trading Days during the period of the ten Trading Days immediately
         preceding the Change in Control is at least equal to 105% of the
         Conversion Price in effect on such day; or

                  (ii) in the case of a merger or consolidation, all of the
         consideration (excluding cash payments for fractional shares in the
         merger or consolidation constituting the Change in Control) consists of
         common stock traded on a United States 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 such Change In
         Control) and as a result of such transaction or transactions the Notes
         become convertible solely into such common stock.

         (b) A Holder may exercise its rights pursuant to this Section 6.09 upon
delivery of a written notice (which shall be in substantially the form entitled
"Option of Holder to Elect Purchase" on the reverse of the Notes and which may
be delivered by letter, overnight courier, hand delivery, facsimile transmission
or in any other written form and, in the case of Global Notes, may be delivered
electronically or by other means in accordance with the Depositary's customary
procedures) of the exercise of such rights (a "CHANGE IN CONTROL PAYMENT
NOTICE") to any Paying Agent at any time prior to the close of business on the
Business Day next preceding the Change in Control Purchase Date.

         Notwithstanding anything herein to the contrary, any Holder delivering
to a Paying Agent the Change in Control Payment Notice contemplated by this
Section 6.09(b) shall have the right to withdraw such Change in Control Payment
Notice in whole or in a portion thereof that is a principal amount of $1,000 or
in an integral multiple thereof at any time prior to the close of business on
the Business Day next preceding the Change in Control Payment Date by delivery
of a written notice of withdrawal to the Paying Agent in accordance with Section
6.09(a) hereof.

         Upon receipt by any Paying Agent of the Change in Control Payment
Notice specified in this Section 6.09(b), the Holder of the Security in respect
of which such Change in Control Payment Notice was given shall (unless such
Change in Control Payment Notice is withdrawn as specified below) thereafter be
entitled to receive the Change in Control Payment Price with respect to such
Note. Such Change in Control Payment Price shall be paid to such Holder promptly
following the later of (i) the Change in Control Payment Date with respect to
such Note (provided the conditions in this Section 6.09(b) have been satisfied)
and (ii) the time of delivery of such Note to a Paying Agent by the Holder
thereof in the manner required by this Section 6.09(b). Notes in respect of
which a Change in Control



                                       38
<PAGE>   44

Payment Notice has been given by the Holder thereof may not be converted into
shares of Common Stock on or after the date of the delivery of such Change in
Control Payment Notice unless such Change in Control Payment Notice has first
been validly withdrawn.

         (c) On the Change of Control Payment Date, the Company shall, to the
extent lawful, (1) accept for payment all Notes or portions thereof properly
tendered pursuant to the Change of Control Offer, (2) deposit with the Paying
Agent an amount equal to the Change of Control Payment in respect of all Notes
or portions thereof so tendered and (3) deliver or cause to be delivered to the
Trustee the Notes so accepted together with an Officers' Certificate stating the
aggregate principal amount of Notes or portions thereof being purchased by the
Company. The Paying Agent shall promptly mail to each Holder of Notes so
tendered payment in an amount equal to the purchase price for the Notes, and the
Trustee shall promptly authenticate and mail (or cause to be transferred by book
entry) to each Holder a new Note equal in principal amount to any unpurchased
portion of the Notes surrendered by such Holder, if any; PROVIDED, that each
such new Note shall be in a principal amount of $1,000 or an integral multiple
thereof. The Company shall publicly announce the results of the Change of
Control Offer on or as soon as practicable after the Change of Control Payment
Date.

         If a Paying Agent holds, in accordance with the terms hereof, money
sufficient to pay the Change in Control Payment Price of any Note for which a
Change in Control Payment Notice has been tendered and not withdrawn in
accordance with this Indenture then, on the Change in Control Payment Date, such
Note will cease to be outstanding and the rights of the Holder in respect
thereof shall terminate (other than the right to receive the Change in Control
Payment Price as aforesaid).

         (d) Notwithstanding anything to the contrary in this Section 6.09, the
Company shall not be required to make a Change of Control Offer upon a Change of
Control if a third party makes the Change of Control Offer in the manner, at the
times and otherwise in compliance with the requirements set forth in this
Section 6.09 hereof and all other provisions of this Indenture applicable to a
Change of Control Offer made by the Company and purchases all Notes validly
tendered and not withdrawn under such Change of Control Offer.

SECTION 6.10. PAYMENT OF ADDITIONAL INTEREST.

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

                                   ARTICLE 7.
                                   SUCCESSORS

SECTION 7.01. MERGER, CONSOLIDATION, OR SALE OF ASSETS.

         The Company shall not, directly or indirectly, consolidate or merge
with or into (whether or not the Company is the surviving corporation), or sell,
assign, transfer, convey or otherwise dispose of all or substantially all of its
properties or assets in one or more related transactions to, another Person
unless (i) the Company is the surviving corporation or the Person formed by or
surviving any such




                                       39
<PAGE>   45

consolidation or merger (if other than the Company) or to which such sale,
assignment, transfer, conveyance or other disposition shall have been made is a
corporation organized or existing under the laws of the United States, any state
thereof or the District of Columbia, (ii) the Person formed by or surviving any
such consolidation or merger (if other than the Company) or the Person to which
such sale, assignment, transfer, conveyance or other disposition shall have been
made assumes all the obligations of the Company under the Registration Rights
Agreement, the Notes and this Indenture pursuant to a supplemental indenture in
a form reasonably satisfactory to the Trustee, (iii) immediately after such
transaction, no Default or Event of Default exists and (iv) the Company or the
surviving corporation, as the case may be, shall have delivered to the Trustee
and Officers' Certificate and an Opinion of Counsel, each stating that such
merger, consolidation, conveyance, transfer or lease comply with this Article
Seven and that all conditions precedent herein provided for relating to such
transaction have been satisfied.

SECTION 7.02. SUCCESSOR CORPORATION SUBSTITUTED.

         Upon any consolidation or merger, or any sale, assignment, transfer,
lease, conveyance or other disposition of all or substantially all of the assets
of the Company in accordance with Section 7.01 hereof, the successor corporation
formed by such consolidation or into or with which the Company is merged or to
which such sale, assignment, transfer, lease, conveyance or other disposition is
made shall succeed to, and be substituted for (so that from and after the date
of such consolidation, merger, sale, lease, conveyance or other disposition, the
provisions of this Indenture referring to the "Company" shall refer instead to
the successor corporation and not to the Company), and may exercise every right
and power of the Company under this Indenture with the same effect as if such
successor Person had been named as the Company herein; PROVIDED, HOWEVER, that
the predecessor Company shall not be relieved from the obligation to pay the
principal of and interest on the Notes except in the case of a sale, assignment,
transfer, conveyance or other disposition of all of the Company's assets that
meets the requirements of Section 7.01 hereof.

                                   ARTICLE 8.
                              DEFAULTS AND REMEDIES

SECTION 8.01. EVENTS OF DEFAULT.

         An "Event of Default" occurs if:

         (a) the Company defaults in the payment when due of interest on, or
Additional Interest with respect to, the Notes and such default continues for a
period of 30 days;

         (b) the Company defaults in the payment when due of principal of or
premium, if any, on the Notes when the same becomes due and payable at maturity,
upon redemption (including in connection with an offer to purchase) or
otherwise;

         (c) the Company fails to comply with any of the provisions of Section
6.09 hereof;

         (d) the Company fails to observe or perform any other covenant,
representation, warranty or other agreement in this Indenture or the Notes for
60 days after notice to the Company by the Trustee or the Holders of at least
25% in aggregate principal amount of the Notes then outstanding voting as a
single class;




                                       40
<PAGE>   46

         (e) the Company fails to provide timely notice of a Change of Control;

         (f) the Company:

                  (i) commences a voluntary case,

                  (ii) consents to the entry of an order for relief against it
         in an involuntary case,

                  (iii) consents to the appointment of a custodian of it or for
         all or substantially all of its property,

                  (iv) makes a general assignment for the benefit of its
         creditors, or

                  (v) generally is not paying its debts as they become due; or

         (g) a court of competent jurisdiction enters an order or decree under
any Bankruptcy Law that:

                  (i) is for relief against the Company in an involuntary case;

                  (ii) appoints a custodian of the Company or for all or
         substantially all of the property of the Company; or

                  (iii) orders the liquidation of the Company;

and the order or decree remains unstayed and in effect for 60 consecutive days.

SECTION 8.02. ACCELERATION.

         If any Event of Default (other than an Event of Default specified in
clause (g) or (h) of Section 8.01 hereof with respect to the Company) occurs and
is continuing, the Trustee or the Holders of at least 25% in principal amount of
the then outstanding Notes may declare all the Notes to be due and payable
immediately. Upon any such declaration, the Notes shall become due and payable
immediately. Notwithstanding the foregoing, if an Event of Default specified in
clause (g) or (h) of Section 8.01 hereof occurs with respect to the Company, all
outstanding Notes shall be due and payable immediately without further action or
notice. The Holders of a majority in aggregate principal amount of the then
outstanding Notes by written notice to the Trustee may on behalf of all of the
Holders rescind an acceleration and its consequences if the rescission would not
conflict with any judgment or decree and if all existing Events of Default
(except nonpayment of principal, interest or premium that has become due solely
because of the acceleration) have been cured or waived.

SECTION 8.03. OTHER REMEDIES.

         If an Event of Default occurs and is continuing, the Trustee may pursue
any available remedy to collect the payment of principal, premium, if any, and
interest on the Notes or to enforce the performance of any provision of the
Notes or this Indenture.

         The Trustee may maintain a proceeding even if it does not possess any
of the Notes or does not produce any of them in the proceeding. A delay or
omission by the Trustee or any Holder of a Note in exercising any right or
remedy accruing upon an Event of Default shall not impair the right or remedy or




                                       41
<PAGE>   47

constitute a waiver of or acquiescence in the Event of Default. All remedies are
cumulative to the extent permitted by law.

SECTION 8.04. WAIVER OF PAST DEFAULTS.

         Subject to Section 8.02, Holders of not less than a majority in
aggregate principal amount of the then outstanding Notes by notice to the
Trustee may on behalf of the Holders of all of the Notes waive an existing
Default or Event of Default and its consequences hereunder, except a continuing
Default or Event of Default in the payment of the principal of, premium and
Additional Interest, if any, or interest on, the Notes (including in connection
with an offer to purchase) or a failure by the Company to convert any Notes into
Common Stock (PROVIDED, HOWEVER, that the Holders of a majority in aggregate
principal amount of the then outstanding Notes may rescind an acceleration and
its consequences, including any related payment default that resulted from such
acceleration). Upon any such waiver, such Default shall cease to exist, and any
Event of Default arising therefrom shall be deemed to have been cured for every
purpose of this Indenture; but no such waiver shall extend to any subsequent or
other Default or impair any right consequent thereon.

SECTION 8.05. CONTROL BY MAJORITY.

         Holders of a majority in principal amount of the then outstanding Notes
may direct the time, method and place of conducting any proceeding for
exercising any remedy available to the Trustee or exercising any trust or power
conferred on it. However, the Trustee may refuse to follow any direction that
conflicts with law or this Indenture that the Trustee determines may be unduly
prejudicial to the rights of other Holders of Notes or that may involve the
Trustee in personal liability.

SECTION 8.06. LIMITATION ON SUITS.

         A Holder of a Note may pursue a remedy with respect to this Indenture
or the Notes only if:

         (a) the Holder of a Note gives to the Trustee written notice of a
continuing Event of Default;

         (b) the Holders of at least 25% in principal amount of the then
outstanding Notes make a written request to the Trustee to pursue the remedy;

         (c) such Holder of a Note or Holders of Notes offer and, if requested,
provide to the Trustee indemnity satisfactory to the Trustee against any loss,
liability or expense;

         (d) the Trustee does not comply with the request within 60 days after
receipt of the request and the offer and, if requested, the provision of
indemnity; and

         (e) during such 60-day period the Holders of a majority in principal
amount of the then outstanding Notes do not give the Trustee a direction
inconsistent with the request.

         A Holder of a Note may not use this Indenture to prejudice the rights
of another Holder of a Note or to obtain a preference or priority over another
Holder of a Note.

SECTION 8.07. RIGHTS OF HOLDERS OF NOTES TO RECEIVE PAYMENT.

         Notwithstanding any other provision of this Indenture, the right of any
Holder of a Note to receive payment of principal, premium and Additional
Interest, if any, and interest on the Note, on or



                                       42
<PAGE>   48

after the respective due dates expressed in the Note (including in connection
with an offer to purchase), to convert such Note in accordance with Article 4 or
to bring suit for the enforcement of any such payment on or after such
respective dates, shall not be impaired or affected without the consent of such
Holder.

SECTION 8.08. COLLECTION SUIT BY TRUSTEE.

         If an Event of Default specified in Section 8.01(a) or (b) occurs and
is continuing, the Trustee is authorized to recover judgment in its own name and
as trustee of an express trust against the Company for the whole amount of
principal of, premium and Additional Interest, if any, and interest remaining
unpaid on the Notes and interest on overdue principal and, to the extent lawful,
interest and such further amount as shall be sufficient to cover the costs and
expenses of collection, including the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel.

SECTION 8.09. TRUSTEE MAY FILE PROOFS OF CLAIM.

         The Trustee is authorized 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 (including any claim for the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel) and the
Holders of the Notes allowed in any judicial proceedings relative to the Company
(or any other obligor upon the Notes), its creditors or its property and shall
be entitled and empowered to collect, receive and distribute any money or other
property payable or deliverable on any such claims and any custodian in any such
judicial proceeding is hereby authorized by each Holder to make such payments to
the Trustee, and in the event that the Trustee shall consent to the making of
such payments directly to the Holders, to pay to the Trustee any amount due to
it for the reasonable compensation, expenses, disbursements and advances of the
Trustee, its agents and counsel, and any other amounts due the Trustee under
Section 9.07 hereof. To the extent that the payment of any such compensation,
expenses, disbursements and advances of the Trustee, its agents and counsel, and
any other amounts due the Trustee under Section 9.07 hereof out of the estate in
any such proceeding, 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, money, securities and other properties that the Holders may be
entitled to receive in such proceeding whether in liquidation or under any plan
of reorganization or arrangement or otherwise. Nothing herein contained shall be
deemed to authorize the Trustee to authorize or consent to or accept or adopt on
behalf of any Holder any plan of reorganization, arrangement, adjustment or
composition affecting the Notes or the rights of any Holder, or to authorize the
Trustee to vote in respect of the claim of any Holder in any such proceeding.

SECTION 8.10. PRIORITIES.

         If the Trustee collects any money pursuant to this Article, it shall
pay out the money in the following order:

                  FIRST: to the Trustee, its agents and attorneys for amounts
         due under Section 9.07 hereof, including payment of all compensation,
         expense and liabilities incurred, and all advances made, by the Trustee
         and the costs and expenses of collection;

                  SECOND: to Holders of Notes for amounts due and unpaid on the
         Notes for principal, premium and Additional Interest, if any, and
         interest, ratably, without preference or priority of




                                       43
<PAGE>   49

         any kind, according to the amounts due and payable on the Notes for
         principal, premium and Additional Interest, if any and interest,
         respectively; and

                  THIRD: to the Company or to such party as a court of competent
         jurisdiction shall direct.

         The Trustee may fix a record date and payment date for any payment to
Holders of Notes pursuant to this Section 8.10.

         SECTION 8.11. UNDERTAKING FOR COSTS.

         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 a Trustee, a court in its discretion may require the filing by any party
litigant in the suit of an undertaking to pay the costs of the suit, and the
court in its discretion may assess reasonable costs, including reasonable
attorneys' fees, against any party litigant in the suit, having due regard to
the merits and good faith of the claims or defenses made by the party litigant.
This Section does not apply to a suit by the Trustee, a suit by a Holder of a
Note pursuant to Section 8.07 hereof, or a suit by Holders of more than 10% in
principal amount of the then outstanding Notes.

                                   ARTICLE 9.
                                     TRUSTEE

         SECTION 9.01. DUTIES OF TRUSTEE.

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

         (b) Except during the continuance of an Event of Default:

                  (i) the duties of the Trustee shall be determined solely by
         the express provisions of this Indenture and the Trustee need perform
         only those duties that are specifically set forth in this Indenture and
         no others, and no implied covenants or obligations shall be read into
         this Indenture against the Trustee; and

                  (ii) in the absence of bad faith on its part, the Trustee may
         conclusively rely, as to the truth of the statements and the
         correctness of the opinions expressed therein, upon certificates or
         opinions furnished to the Trustee and conforming to the requirements of
         this Indenture. However, the Trustee shall examine the certificates and
         opinions to determine whether or not they conform to the requirements
         of this Indenture.

         (c) The Trustee may not be relieved from liabilities for its own
negligent action, its own negligent failure to act, or its own willful
misconduct, except that:

                  (i) this paragraph does not limit the effect of paragraph (b)
         of this Section;





                                       44
<PAGE>   50

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

                  (iii) the Trustee shall not be liable with respect to any
         action it takes or omits to take in good faith in accordance with a
         direction received by it pursuant to Section 7.05 hereof.

         (d) Whether or not therein expressly so provided, every provision of
this Indenture that in any way relates to the Trustee is subject to paragraphs
(a), (b), and (c) of this Section.

         (e) No provision of this Indenture shall require the Trustee to expend
or risk its own funds or incur any liability. The Trustee shall be under no
obligation to exercise any of its rights and powers under this Indenture at the
request of any Holders, unless such Holder shall have offered to the Trustee
security and indemnity satisfactory to it against any loss, liability or
expense.

         (f) The Trustee shall not be liable for interest on any money received
by it except as the Trustee may agree in writing with the Company. Money held in
trust by the Trustee need not be segregated from other funds except to the
extent required by law.

SECTION 9.02. RIGHTS OF TRUSTEE.

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

         (b) Before the Trustee acts or refrains from acting, it may require an
Officers' Certificate or an Opinion of Counsel or both. The Trustee shall not be
liable for any action it takes or omits to take in good faith in reliance on
such Officers' Certificate or Opinion of Counsel. The Trustee may consult with
counsel and the written advice of such counsel or any Opinion of Counsel shall
be full and complete authorization and protection from liability in respect of
any action taken, suffered or omitted by it hereunder in good faith and in
reliance thereon.

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

         (d) The Trustee shall not be liable for any action it takes or omits to
take in good faith that it believes to be authorized or within the rights or
powers conferred upon it by this Indenture.

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

         (f) The Trustee shall be under no obligation to exercise any of the
rights or powers vested in it by this Indenture at the request or direction of
any of the Holders unless such Holders shall have offered to the Trustee
reasonable security or indemnity against the costs, expenses and liabilities
that might be incurred by it in compliance with such request or direction.

         (g) The Trustee shall not be charged with knowledge of any Default or
Event of Default with respect to the Notes unless either (1) a Responsible
Officer shall have actual




                                       45
<PAGE>   51

knowledge of such Default or Event of Default or (2) written notice of such
Default or Event of Default shall have been given to the Trustee by the Company
of by any Holder of the Notes.

SECTION 9.03. INDIVIDUAL RIGHTS OF TRUSTEE.

         The Trustee in its individual or any other capacity may become the
owner or pledgee of Notes and may otherwise deal with the Company or any
Affiliate of the Company with the same rights it would have if it were not
Trustee. However, in the event that the Trustee acquires any conflicting
interest it must eliminate such conflict within 90 days, apply to the SEC for
permission to continue as trustee or resign. Any Agent may do the same with like
rights and duties. The Trustee is also subject to Sections 9.10 and 9.11 hereof.

SECTION 9.04. TRUSTEE'S DISCLAIMER.

         The Trustee shall not be responsible for and makes no representation as
to the validity or adequacy of this Indenture or the Notes, it shall not be
accountable for the Company's use of the proceeds from the Notes or any money
paid to the Company or upon the Company's direction under any provision of this
Indenture, it shall not be responsible for the use or application of any money
received by any Paying Agent other than the Trustee, and it shall not be
responsible for any statement or recital herein or any statement in the Notes or
any other document in connection with the sale of the Notes or pursuant to this
Indenture other than its certificate of authentication.

SECTION 9.05. NOTICE OF DEFAULTS.

         If a Default or Event of Default occurs and is continuing and if it is
known to the Trustee, the Trustee shall mail to Holders of Notes a notice of the
Default or Event of Default within 90 days after it occurs. Except in the case
of a Default or Event of Default in payment of principal of, premium, if any, or
interest on any Note, the Trustee may withhold the notice if and so long as a
committee of its Responsible Officers in good faith determines that withholding
the notice is in the interests of the Holders of the Notes.

SECTION 9.06. REPORTS BY TRUSTEE TO HOLDERS OF THE NOTES.

         Within 60 days after each May 15 beginning with the May 15 following
the date of this Indenture, and for so long as Notes remain outstanding, the
Trustee shall mail to the Holders of the Notes a brief report dated as of such
reporting date that complies with TIA ss. 313(a) (but if no event described in
TIA ss. 313(a) has occurred within the twelve months preceding the reporting
date, no report need be transmitted). The Trustee also shall comply with TIA ss.
313(b)(2). The Trustee shall also transmit by mail all reports as required by
TIA ss. 313(c).

         A copy of each report at the time of its mailing to the Holders of
Notes shall be mailed to the Company and filed with the SEC and each stock
exchange on which the Notes are listed in accordance with TIA ss. 313(d). The
Company shall promptly notify the Trustee when the Notes are listed on any stock
exchange.

SECTION 9.07. COMPENSATION AND INDEMNITY.

         The Company shall pay to the Trustee from time to time reasonable
compensation for its acceptance of this Indenture and services hereunder. The
Trustee's compensation shall not be limited by




                                       46
<PAGE>   52

any law on compensation of a trustee of an express trust. The Company shall
reimburse the Trustee promptly upon request for all reasonable disbursements,
advances and expenses incurred or made by it in addition to the compensation for
its services. Such expenses shall include the reasonable compensation,
disbursements and expenses of the Trustee's agents and counsel.

         The Company shall indemnify the Trustee against any and all losses,
liabilities or expenses incurred by it arising out of or in connection with the
acceptance or administration of its duties under this Indenture, including the
costs and expenses of enforcing this Indenture against the Company (including
this Section 9.07) and defending itself against any claim (whether asserted by
the Company or any Holder or any other person) or liability in connection with
the exercise or performance of any of its powers or duties hereunder, except to
the extent any such loss, liability or expense may be attributable to its
negligence or bad faith. The Trustee shall notify the Company promptly of any
claim for which it may seek indemnity. Failure by the Trustee to so notify the
Company shall not relieve the Company of its obligations hereunder. The Company
shall defend the claim and the Trustee shall cooperate in the defense. The
Trustee may have separate counsel and the Company shall pay the reasonable fees
and expenses of such counsel. The Company need not pay for any settlement made
without its consent, which consent shall not be unreasonably withheld.

         The obligations of the Company under this Section 9.07 shall survive
the resignation or removal of the Trustee and the satisfaction and discharge of
this Indenture.

         To secure the Company's payment obligations in this Section, the
Trustee shall have a Lien prior to the Notes on all money or property held or
collected by the Trustee, except that held in trust to pay principal and
interest on particular Notes. Such Lien shall survive the satisfaction and
discharge of this Indenture.

         When the Trustee incurs expenses or renders services after an Event of
Default specified in Section 8.01(g) or (h) hereof occurs, the expenses and the
compensation for the services (including the fees and expenses of its agents and
counsel) are intended to constitute expenses of administration under any
Bankruptcy Law.

         The Trustee shall comply with the provisions of TIA ss. 313(b)(2) to
the extent applicable.

SECTION 9.08. REPLACEMENT OF TRUSTEE.

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

         The Trustee may resign in writing at any time and be discharged from
the trust hereby created by so notifying the Company. The Holders of a majority
in principal amount of the then outstanding Notes may remove the Trustee by so
notifying the Trustee and the Company in writing. The Company may remove the
Trustee if:

         (a) the Trustee fails to comply with Section 9.10 hereof;

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

         (c) a custodian or public officer takes charge of the Trustee or its
property; or




                                       47
<PAGE>   53

         (d) the Trustee becomes incapable of acting.

         If the Trustee resigns or is removed or if a vacancy exists in the
office of Trustee for any reason, the Company shall promptly appoint a successor
Trustee. Within one year after the successor Trustee takes office, the Holders
of a majority in principal amount of the then outstanding Notes may appoint a
successor Trustee to replace the successor Trustee appointed by the Company.

         If a successor Trustee does not take office within 60 days after the
retiring Trustee resigns or is removed, the retiring Trustee, the Company, or
the Holders of at least 10% in principal amount of the then outstanding Notes
may petition any court of competent jurisdiction for the appointment of a
successor Trustee.

         If the Trustee, after written request by any Holder who has been a
Holder for at least six months, fails to comply with Section 9.10, such Holder
may petition any court of competent jurisdiction for the removal of the Trustee
and the appointment of a successor Trustee.

         A successor Trustee shall deliver a written acceptance of its
appointment to the retiring Trustee and to the Company. Thereupon, the
resignation or removal of the retiring Trustee shall become effective, and the
successor Trustee shall have all the rights, powers and duties of the Trustee
under this Indenture. The successor Trustee shall mail a notice of its
succession to Holders. The retiring Trustee shall promptly transfer all property
held by it as Trustee to the successor Trustee, PROVIDED all sums owing to the
Trustee hereunder have been paid and subject to the Lien provided for in Section
9.07 hereof. Notwithstanding replacement of the Trustee pursuant to this Section
9.08, the Company's obligations under Section 9.07 hereof shall continue for the
benefit of the retiring Trustee.

SECTION 9.09. SUCCESSOR TRUSTEE BY MERGER, ETC.

         If the Trustee consolidates, merges or converts into, or transfers all
or substantially all of its corporate trust business to, another corporation,
the successor corporation without any further act shall be the successor
Trustee.

SECTION 9.10. ELIGIBILITY; DISQUALIFICATION.

         There shall at all times be a Trustee hereunder that is a corporation
organized and doing business under the laws of the United States of America or
of any state thereof that is authorized under such laws to exercise corporate
trustee power, that is subject to supervision or examination by federal or state
authorities and that has a combined capital and surplus of at least $100 million
as set forth in its most recent published annual report of condition.

         This Indenture shall always have a Trustee who satisfies the
requirements of TIA ss. 310(a)(1), (2) and (5). The Trustee is subject to TIA
ss. 310(b).

SECTION 9.11. PREFERENTIAL COLLECTION OF CLAIMS AGAINST COMPANY.

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





                                       48
<PAGE>   54

                                  ARTICLE 10.
                           SATISFACTION AND DISCHARGE

SECTION 10.01.    SATISFACTION AND DISCHARGE.

         This Indenture will be discharged and will cease to be of further
effect as to all Notes issued hereunder, when:

(1)      either:

         (a)      all Notes that have been authenticated (except lost, stolen or
                  destroyed Notes that have been replaced or paid and Notes for
                  whose payment money has theretofore been deposited in trust
                  and thereafter repaid to the Company) have been delivered to
                  the Trustee for cancellation; or

         (b)      all Notes that have not been delivered to the Trustee for
                  cancellation have become due and payable by reason of the
                  making of a notice of redemption or otherwise or will become
                  due and payable within one year and the Company has
                  irrevocably deposited or caused to be deposited with the
                  Trustee as trust funds in trust solely for the benefit of the
                  Holders, cash in U.S. dollars, non-callable Government
                  Securities, or a combination thereof, in such amounts as will
                  be sufficient without consideration of any reinvestment of
                  interest, to pay and discharge the entire indebtedness on the
                  Notes not delivered to the Trustee for cancellation for
                  principal, premium and Additional Interest, if any, and
                  accrued interest to the date of maturity or redemption;

(2)      no Default or Event of Default shall have occurred and be continuing on
         the date of such deposit or shall occur as a result of such deposit and
         such deposit will not result in a breach or violation of, or constitute
         a default under, any other instrument to which the Company is a party
         or by which the Company is bound;

(3)      the Company has paid or caused to be paid all sums payable by it under
         this Indenture; and

(4)      the Company has delivered irrevocable instructions to the Trustee under
         this Indenture to apply the deposited money toward the payment of the
         Notes at maturity or the redemption date, as the case may be.

In addition, the Company must deliver an Officers' Certificate and an Opinion of
Counsel to the Trustee stating that all conditions precedent to satisfaction and
discharge have been satisfied.

         Notwithstanding the satisfaction and discharge of this Indenture, if
money shall have been deposited with the Trustee pursuant to subclause (b) of
clause (1) of this Section, the provisions of Section 10.02 shall survive.

SECTION 10.02. APPLICATION OF TRUST MONEY.

         All money deposited with the Trustee pursuant to Section 10.01 shall be
held in trust and applied by it, in accordance with the provisions of the Notes
and this Indenture, to the payment, either directly or through any Paying Agent
(including the Company acting as its own Paying Agent) as the Trustee may
determine, to the Persons entitled thereto, of the principal (and premium, if
any) and interest for whose




                                       49
<PAGE>   55

payment such money has been deposited with the Trustee; but such money need not
be segregated from other funds except to the extent required by law.

         If the Trustee or Paying Agent is unable to apply any money or
Government Securities in accordance with Section 10.01 by reason of any legal
proceeding or by reason of any order or judgment of any court or governmental
authority enjoining, restraining or otherwise prohibiting such application, the
Company's obligations under this Indenture and the Notes shall be revived and
reinstated as though no deposit had occurred pursuant to Section 10.01; PROVIDED
that if the Company has made any payment of principal of, premium, if any, or
interest on any Notes because of the reinstatement of its obligations, the
Company shall be subrogated to the rights of the Holders of such Notes to
receive such payment from the money or Government Securities held by the Trustee
or Paying Agent.

SECTION 10.03. REPAYMENT TO COMPANY.

         The Trustee and each Paying Agent shall promptly pay to the Company
upon request any excess money (i) deposited with them pursuant to Section 10.1
and (ii) held by them at any time.

         The Trustee and each Paying Agent shall pay to the Company upon request
any money held by them for the payment of principal or interest that remains
unclaimed for two years after a right to such money has matured; provided,
however, that the Trustee or such Paying Agent, before being required to make
any such payment, may at the expense of the Company cause to be mailed to each
Holder entitled to such money notice that such money remains unclaimed and that
after a date specified therein, which shall be at least 30 days from the date of
such mailing, any unclaimed balance of such money then remaining will be repaid
to the Company. After payment to the Company, Holders entitled to money must
look to the Company for payment as general creditors.

SECTION 10.04. REINSTATEMENT.

         If the Trustee or any Paying Agent is unable to apply any money in
accordance with Section 10.2 by reason of any legal proceeding or by reason of
any order or judgment of any court or governmental authority enjoining,
restraining or otherwise prohibiting such application, then the Company's
obligations under this Indenture and the Notes shall be revived and reinstated
as though no deposit had occurred pursuant to Section 10.1 until such time as
the Trustee or such Paying Agent is permitted to apply all such money in
accordance with Section 10.2; provided, however, that if the Company has made
any payment of the principal of or interest on any Notes because of the
reinstatement of its obligations, the Company shall be subrogated to the rights
of the Holders of such Notes to receive any such payment from the money held by
the Trustee or such Paying Agent.

                                  ARTICLE 11.
                        AMENDMENT, SUPPLEMENT AND WAIVER

SECTION 11.01. WITHOUT CONSENT OF HOLDERS OF NOTES.

         Notwithstanding Section 11.02 of this Indenture, the Company and the
Trustee may amend or supplement this Indenture or the Notes without the consent
of any Holder of a Note:

         (a) to cure any ambiguity, defect or inconsistency;





                                       50
<PAGE>   56

         (b) to provide for uncertificated Notes in addition to or in place of
certificated Notes or to alter the provisions of Article 2 hereof (including the
related definitions) in a manner that does not materially adversely affect any
Holder;

         (c) to provide for the assumption of the Company's obligations to the
Holders of the Notes by a successor to the Company pursuant to Article 7 hereof;

         (d) to make any change that would provide any additional rights or
benefits to the Holders of the Notes or that does not adversely affect the legal
rights hereunder of any Holder of the Note;

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

         (f) to provide for the issuance of additional Notes pursuant to the
purchasers option set forth in the Purchase Agreement.

         Upon the request of the Company accompanied by a resolution of its
Board of Directors authorizing the execution of any such amended or supplemental
Indenture, and upon receipt by the Trustee of the documents described in Section
9.02 hereof, the Trustee shall join with the Company in the execution of any
amended or supplemental Indenture authorized or permitted by the terms of this
Indenture and to make any further appropriate agreements and stipulations that
may be therein contained, but the Trustee shall not be obligated to enter into
such amended or supplemental Indenture that affects its own rights, duties or
immunities under this Indenture or otherwise.

SECTION 11.02. WITH CONSENT OF HOLDERS OF NOTES.

         Except as provided below in this Section 11.02, the Company and the
Trustee may amend or supplement this Indenture (including Section 6.09 hereof)
and the Notes with the consent of the Holders of at least a majority in
principal amount of the Notes then outstanding voting as a single class
(including consents obtained in connection with a tender offer or exchange offer
for, or purchase of, the Notes), and, subject to Sections 8.04 and 8.07 hereof,
any existing Default or Event of Default (other than a Default or Event of
Default in the payment of the principal of, premium, if any, or interest on the
Notes, except a payment default resulting from an acceleration that has been
rescinded) or compliance with any provision of this Indenture or the Notes may
be waived with the consent of the Holders of a majority in principal amount of
the then outstanding Notes voting as a single class (including consents obtained
in connection with a tender offer or exchange offer for, or purchase of, the
Notes). Section 2.08 hereof shall determine which Notes are considered to be
"outstanding" for purposes of this Section 11.02.

         Upon the request of the Company accompanied by a resolution of its
Board of Directors authorizing the execution of any such amended or supplemental
Indenture, and upon the filing with the Trustee of evidence satisfactory to the
Trustee of the consent of the Holders of Notes as aforesaid, and upon receipt by
the Trustee of the documents described in Section 9.02 hereof, the Trustee shall
join with the Company in the execution of such amended or supplemental Indenture
unless such amended or supplemental Indenture directly 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 amended or supplemental Indenture.





                                       51
<PAGE>   57

         It shall not be necessary for the consent of the Holders of Notes under
this Section 11.02 to approve the particular form of any proposed amendment or
waiver, but it shall be sufficient if such consent approves the substance
thereof.

         After an amendment, supplement or waiver under this Section becomes
effective, the Company shall mail to the Holders of Notes affected thereby a
notice briefly describing the amendment, supplement or waiver. Any failure of
the Company to mail such notice, or any defect therein, shall not, however, in
any way impair or affect the validity of any such amended or supplemental
Indenture or waiver. Subject to Sections 8.04 and 8.07 hereof, the Holders of a
majority in aggregate principal amount of the Notes then outstanding voting as a
single class may waive compliance in a particular instance by the Company with
any provision of this Indenture or the Notes. However, without the consent of
each Holder affected, an amendment or waiver under this Section 11.02 may not
(with respect to any Notes held by a non-consenting Holder):

         (a) reduce the principal amount of Notes whose Holders must consent to
an amendment, supplement or waiver;

         (b) reduce the principal of or change the fixed maturity of any Note or
alter or waive any of the provisions with respect to the redemption of the Notes
except as provided above with respect to Section 6.09 hereof;

         (c) reduce the rate of or change the time for payment of interest,
including default interest, on any Note;

         (d) waive a Default or Event of Default in the payment of principal of
or premium, if any, or interest on the Notes (except a rescission of
acceleration of the Notes by the Holders of at least a majority in aggregate
principal amount of the then outstanding Notes and a waiver of the payment
default that resulted from such acceleration);

         (e) make any Note payable in money other than that stated in the Notes;

         (f) make any change in the provisions of this Indenture relating to
waivers of past Defaults or the rights of Holders of Notes to receive payments
of principal of or interest on the Notes; or

         (g) make any change in Section 8.04 or 8.07 hereof or in the foregoing
amendment and waiver provisions.

SECTION 11.03. COMPLIANCE WITH TRUST INDENTURE ACT.

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

SECTION 11.04. REVOCATION AND EFFECT OF CONSENTS.

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



                                       52
<PAGE>   58

supplement or amendment becomes effective. An amendment, supplement or waiver
becomes effective in accordance with its terms and thereafter binds every
Holder.

SECTION 11.05. NOTATION ON OR EXCHANGE OF NOTES.

         The Trustee may place an appropriate notation about an amendment,
supplement or waiver on any Note thereafter authenticated. The Company in
exchange for all Notes may issue and the Trustee shall, upon receipt of an
Authentication Order, authenticate new Notes that reflect the amendment,
supplement or waiver.

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

SECTION 11.06. TRUSTEE TO SIGN AMENDMENTS, ETC.

         The Trustee shall sign any amended or supplemental Indenture authorized
pursuant to this Article Nine if the amendment or supplement does not adversely
affect the rights, duties, liabilities or immunities of the Trustee. The Company
may not sign an amendment or supplemental Indenture until the Board of Directors
approves it. In executing any amended or supplemental indenture, the Trustee
shall be entitled to receive and (subject to Section 9.01 hereof) shall be fully
protected in relying upon, in addition to the documents required by Section
12.04 hereof, an Officer's Certificate and an Opinion of Counsel stating that
the execution of such amended or supplemental indenture is authorized or
permitted by this Indenture.

                                  ARTICLE 12.
                                  MISCELLANEOUS

SECTION 12.01. TRUST INDENTURE ACT CONTROLS.

         If any provision of this Indenture limits, qualifies or conflicts with
the duties imposed by TIA ss.318(c), the imposed duties shall control.

SECTION 12.02. NOTICES.

         Any notice or communication by the Company or the Trustee to the others
is duly given if in writing and delivered in Person or mailed by first class
mail (registered or certified, return receipt requested), telex, telecopier or
overnight air courier guaranteeing next day delivery, to the others' address:

         If to the Company:

         EMCORE Corporation
         145 Belmont Drive
         Somerset, New Jersey 08873
         Telecopier No.:  (732) 271-9686
         Attention:  Chief Financial Officer





                                       53
<PAGE>   59

         With a copy to:
         White & Case, LLP
         200 South Biscayne Boulevard
         Miami, Florida 33131
         Telecopier No.:  (305) 358-5744
         Attention:  Jorge L. Freeland, Esq.

         If to the Trustee:
         Wilmington Trust Company
         Rodney Square North
         1100 North Market Street
         Wilmington, Delaware  19890
         Telecopier No.:  (302) 651-8882
         Attention:  Bruce L. Bisson

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

         All notices and communications (other than those sent to Holders) shall
be deemed to have been duly given: at the time delivered by hand, if personally
delivered; five Business Days after being deposited in the mail, postage
prepaid, if mailed; when answered back, if telexed; when receipt acknowledged,
if telecopied; and the next Business Day after timely delivery to the courier,
if sent by overnight air courier guaranteeing next day delivery.

         Any notice or communication to a Holder shall be mailed by first class
mail, certified or registered, return receipt requested, or by overnight air
courier guaranteeing next day delivery to its address shown on the register kept
by the Registrar. Any notice or communication shall also be so mailed to any
Person described in TIA ss. 313(c), to the extent required by the TIA. Failure
to mail a notice or communication to a Holder or any defect in it shall not
affect its sufficiency with respect to other Holders.

         If a notice or communication is mailed in the manner provided above
within the time prescribed, it is duly given, whether or not the addressee
receives it.

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

SECTION 12.03. COMMUNICATION BY HOLDERS OF NOTES WITH OTHER HOLDERS OF NOTES.

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

SECTION 12.04. CERTIFICATE AND OPINION AS TO CONDITIONS PRECEDENT.

         Upon any request or application by the Company to the Trustee to take
any action under this Indenture, the Company shall furnish to the Trustee:

         (a) an Officers' Certificate in form and substance reasonably
satisfactory to the Trustee (which shall include the statements set forth in
Section 12.05 hereof) stating that, in the opinion of the




                                       54
<PAGE>   60

signers, all conditions precedent and covenants, if any, provided for in this
Indenture relating to the proposed action have been satisfied; and

(b) an Opinion of Counsel in form and substance reasonably satisfactory to the
Trustee (which shall include the statements set forth in Section 12.05 hereof)
stating that, in the opinion of such counsel, all such conditions precedent and
covenants have been satisfied.

SECTION 12.05. STATEMENTS REQUIRED IN CERTIFICATE OR OPINION.

         Each certificate or opinion with respect to compliance with a condition
or covenant provided for in this Indenture (other than a certificate provided
pursuant to TIA ss. 314(a)(4)) shall comply with the provisions of TIA ss.
314(e) and shall include:

         (a) a statement that the Person making such certificate or opinion has
read such covenant or condition;

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

         (c) a statement that, in the opinion of such Person, he or she 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
satisfied; and

         (d) a statement as to whether or not, in the opinion of such Person,
such condition or covenant has been satisfied.

SECTION 12.06. RULES BY TRUSTEE AND AGENTS.

         The Trustee may make reasonable rules for action by or at a meeting of
Holders. The Registrar or Paying Agent may make reasonable rules and set
reasonable requirements for its functions.

SECTION 12.07. NO PERSONAL LIABILITY OF DIRECTORS, OFFICERS, EMPLOYEES AND
               STOCKHOLDERS.

         No past, present or future director, officer, employee, incorporator or
stockholder of the Company, as such, shall have any liability for any
obligations of the Company under the Notes, this Indenture or for any claim
based on, in respect of, or by reason of, such obligations or their creation.
Each Holder by accepting a Note waives and releases all such liability. The
waiver and release are part of the consideration for issuance of the Notes.

SECTION 12.08. GOVERNING LAW.

         THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED TO
CONSTRUE THIS INDENTURE, THE NOTES WITHOUT GIVING EFFECT TO APPLICABLE
PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF
ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.





                                       55
<PAGE>   61

SECTION 12.09. NO ADVERSE INTERPRETATION OF OTHER AGREEMENTS.

         This Indenture may not be used to interpret any other indenture, loan
or debt agreement of the Company or its Subsidiaries or of any other Person. Any
such indenture, loan or debt agreement may not be used to interpret this
Indenture.

SECTION 12.10. SUCCESSORS.

         All agreements of the Company in this Indenture and the Notes shall
bind its successors. All agreements of the Trustee in this Indenture shall bind
its successors.

SECTION 12.11. SEVERABILITY.

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

SECTION 12.12. COUNTERPART ORIGINALS.

         The parties may sign any number of copies of this Indenture. Each
signed copy shall be an original, but all of them together represent the same
agreement.

SECTION 12.13. TABLE OF CONTENTS, HEADINGS, ETC.

         The Table of Contents, Cross-Reference Table 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 of this Indenture and shall in
no way modify or restrict any of the terms or provisions hereof.

                         [Signatures on following page]






                                       56
<PAGE>   62


                                   SIGNATURES



Dated as of May 7, 2001
                                       EMCORE Corporation




                                       By: /s/ Howard Brodie
                                           -------------------------------------
                                           Name: Howard Brodie
                                           Title: Vice President



                                       Wilmington Trust Company,
                                       as Trustee



                                       By: /s/ James D. Nesci
                                           -------------------------------------
                                           Name: James D. Nesci
                                           Title: Authorized Signer