<PAGE>

                                                                     EXHIBIT 4.1



                                                               Execution Version
--------------------------------------------------------------------------------


                            RIVERSTONE NETWORKS, INC.

                                       To

            STATE STREET BANK AND TRUST COMPANY OF CALIFORNIA, N.A.,

                                   as Trustee


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


                                    INDENTURE



                                   Dated as of

                                November 21, 2001


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

                 3 3/4% Convertible Subordinated Notes Due 2006

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


<PAGE>


                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                            Page
                                                                            ----
<S>                                                                         <C>
ARTICLE ONE DEFINITIONS .................................................      2
    Section 1.1  Definitions ............................................      2
        Affiliate .......................................................      2
        Board of Directors ..............................................      2
        Business Day ....................................................      2
        Cash Conversion Notice ..........................................      2
        Closing Price ...................................................      2
        Commission ......................................................      2
        Common Stock ....................................................      2
        Company .........................................................      3
        Company Notice ..................................................      3
        Conversion Date .................................................      3
        Conversion Price ................................................      3
        Conversion Rate .................................................      3
        Corporate Trust Office ..........................................      3
        Custodian .......................................................      3
        default .........................................................      3
        Defaulted Interest ..............................................      3
        Depositary ......................................................      3
        Designated Senior Indebtedness ..................................      3
        Event of Default ................................................      4
        Exchange Act ....................................................      4
        Fundamental Change ..............................................      4
        Global Note .....................................................      4
        Indebtedness ....................................................      4
        Indenture .......................................................      5
        Initial Purchaser ...............................................      5
        Institutional Accredited Investor ...............................      5
        Liquidated Damages ..............................................      5
        Make-Whole Payment ..............................................      5
        New Rights Plan .................................................      5
        Non-Payment Default .............................................      5
        Non-Provisional Redemption ......................................      5
        Note or Notes ...................................................      5
        Note register ...................................................      5
        Note registrar ..................................................      5
        Noteholder or holder ............................................      5
        Notice Date .....................................................      5
        Officers' Certificate ...........................................      5
        Opinion of Counsel ..............................................      6
</TABLE>


                                      -i-

<PAGE>

                                TABLE OF CONTENTS
                                  (continued)
<TABLE>
<CAPTION>
                                                                            Page
                                                                            ----
<S>                                                                         <C>
        outstanding .....................................................      6
        Payment Blockage Notice .........................................      6
        Person ..........................................................      6
        Portal Market ...................................................      6
        Predecessor .....................................................      6
        Provisional Redemption ..........................................      6
        Provisional Redemption Date .....................................      6
        Purchased Shares ................................................      6
        QIB .............................................................      7
        Registration Rights Agreement ...................................      7
        Representative ..................................................      7
        Responsible Officer .............................................      7
        Restricted Securities ...........................................      7
        Rights Agreement ................................................      7
        Rule 144A .......................................................      7
        Securities Act ..................................................      7
        Senior Indebtedness .............................................      7
        Significant Subsidiary ..........................................      8
        Subsidiary ......................................................      8
        Trading Day .....................................................      8
        Trigger Event ...................................................      8
        Trust Indenture Act .............................................      8
        Trustee .........................................................      8
ARTICLE TWO ISSUE, DESCRIPTION, EXECUTION, REGISTRATION AND EXCHANGE
 OF NOTES ...............................................................      8
    Section 2.1  Designation Amount and Issue of Notes                         8
    Section 2.2  Form of Notes                                                 9
    Section 2.3  Date and Denomination of Notes; Payments of Interest          9
    Section 2.4  Execution of Notes .....................................     11
    Section 2.5  Exchange and Registration of Transfer Notes;
                 Restrictions on Transfer; Depositary ...................     11
    Section 2.6  Mutilated, Destroyed, Lost or Stolen Notes .............     19
    Section 2.7  Temporary Notes ........................................     20
    Section 2.8  Cancellation of Notes Paid, Etc ........................     20
    Section 2.9  CUSIP Numbers ..........................................     21
ARTICLE THREE REDEMPTION OF NOTES .......................................     21
    Section 3.1  Redemption by the Company ..............................     21
    Section 3.2  Notice of Redemptions; Selection of Notes ..............     22
    Section 3.3  Payment of Notes Called for Redemption .................     24
</TABLE>


                                      -ii-

<PAGE>

                                TABLE OF CONTENTS
                                  (continued)
<TABLE>
<CAPTION>
                                                                            Page
                                                                            ----
<S>                                                                         <C>
    Section 3.4  Conversion Arrangement on Call for Redemption ..........     24
    Section 3.5  Redemption at Option of Holders ........................     25
ARTICLE FOUR SUBORDINATION OF NOTES .....................................     27
    Section 4.1  Agreement of Subordination .............................     27
    Section 4.2  Payments to Noteholders ................................     27
    Section 4.3  Subrogation of Notes ...................................     30
    Section 4.4  Authorization to Effect Subordination ..................     31
    Section 4.5  Notice to Trustee ......................................     31
    Section 4.6  Trustee's Relation to Senior Indebtedness ..............     32
    Section 4.7  No Impairment of Subordination .........................     32
    Section 4.8  Certain Conversions Not Deemed Payment .................     32
    Section 4.9  Article Applicable to Paying Agents ....................     33
    Section 4.10 Senior Indebtedness Entitled to Rely ...................     33
    Section 4.11 Reliance on Judicial Order or Certificate of Liquidating
                 Agent ..................................................     33
ARTICLE FIVE PARTICULAR COVENANTS OF THE COMPANY ........................     34
    Section 5.1  Payment of Principal, Premium and Interest .............     34
    Section 5.2  Maintenance of Office or Agency ........................     34
    Section 5.3  Appointments to Fill Vacancies in Trustee's Office .....     34
    Section 5.4  Provisions as to Paying Agent ..........................     34
    Section 5.5  Existence ..............................................     36
    Section 5.6  Maintenance of Properties ..............................     36
    Section 5.7  Payment of Taxes and Other Claims ......................     36
    Section 5.8  Rule 144A Information Requirement ......................     37
    Section 5.9  Stay, Extension and Usury Laws .........................     37
    Section 5.10 Compliance Certificate .................................     37
    Section 5.11 Liquidated Damages .....................................     38
ARTICLE SIX NOTEHOLDERS' LISTS AND REPORTS BY THE COMPANY AND THE
 TRUSTEE ................................................................     38
    Section 6.1  Noteholders' Lists .....................................     38
    Section 6.2  Preservation and Disclosure of Lists ...................     38
    Section 6.3  Reports by Trustee .....................................     38
    Section 6.4  Reports by Company .....................................     39
ARTICLE SEVEN REMEDIES OF THE TRUSTEE AND NOTEHOLDERS ON AN EVENT OF
 DEFAULT ................................................................     39
    Section 7.1  Events of Default ......................................     39
    Section 7.2  Payments of Notes on Default; Suit Therefor ............     41
    Section 7.3  Application of Monies Collected by Trustee .............     43
</TABLE>


                                      -iii-

<PAGE>

                                TABLE OF CONTENTS
                                  (continued)
<TABLE>
<CAPTION>
                                                                            Page
                                                                            ----
<S>                                                                         <C>
    Section 7.4  Proceedings by Noteholder ..............................     43
    Section 7.5  Proceedings by Trustee .................................     44
    Section 7.6  Remedies Cumulative and Continuing .....................     44
    Section 7.7  Direction of Proceedings and Waiver of Defaults by
                 Majority of Noteholders ................................     45
    Section 7.8  Notice of Defaults .....................................     45
    Section 7.9  Undertaking to Pay Costs ...............................     45
ARTICLE EIGHT THE TRUSTEE ...............................................     46
    Section 8.1  Duties and Responsibilities of Trustee .................     46
    Section 8.2  Reliance on Documents, Opinions, Etc ...................     47
    Section 8.3  No Responsibility for Recitals, Etc ....................     48
    Section 8.4  Trustee, Paying Agents, Conversion Agents or
                 Registrar May Own Notes ................................     48
    Section 8.5  Monies to be Held in Trust .............................     48
    Section 8.6  Compensation and Expenses of Trustee ...................     49
    Section 8.7  Officers' Certificate as Evidence ......................     49
    Section 8.8  Conflicting Interests of Trustee .......................     49
    Section 8.9  Eligibility of Trustee .................................     49
    Section 8.10 Resignation or Removal of Trustee ......................     50
    Section 8.11 Acceptance by Successor Trustee ........................     51
    Section 8.12 Succession by Merger, Etc ..............................     52
    Section 8.13 Preferential Collection of Claims ......................     52
    Section 8.14 Trustee's Application for Instructions from the
                 Company ................................................     52
ARTICLE NINE THE NOTEHOLDERS ............................................     53
    Section 9.1  Action by Noteholders ..................................     53
    Section 9.2  Proof of Execution by Noteholders ......................     53
    Section 9.3  Who Are Deemed Absolute Owners .........................     53
    Section 9.4  Company-Owned Notes Disregarded ........................     53
    Section 9.5  Revocation of Consents; Future Holders Bound ...........     54
ARTICLE TEN MEETINGS OF NOTEHOLDERS .....................................     54
    Section 10.1 Purpose of Meetings ....................................     54
    Section 10.2 Call of Meetings by Trustee ............................     55
    Section 10.3 Call of Meetings by Company or Noteholders .............     55
    Section 10.4 Qualifications for Voting ..............................     55
    Section 10.5 Regulations ............................................     55
    Section 10.6 Voting .................................................     56
    Section 10.7 No Delay of Rights by Meeting ..........................     56
</TABLE>


                                      -iv-

<PAGE>

                                TABLE OF CONTENTS
                                  (continued)
<TABLE>
<CAPTION>
                                                                            Page
                                                                            ----
<S>                                                                         <C>
ARTICLE ELEVEN SUPPLEMENTAL INDENTURES ..................................     56
     Section 11.1 Supplemental Indentures Without Consent of
                  Noteholders ...........................................     56
     Section 11.2 Supplemental Indenture with Consent of Noteholders ....     58
     Section 11.3 Effect of Supplemental Indenture ......................     59
     Section 11.4 Notation on Notes .....................................     59
     Section 11.5 Evidence of Compliance of Supplemental Indenture
                  to be Furnished to Trustee ............................     59
ARTICLE TWELVE CONSOLIDATION, MERGER, SALE, CONVEYANCE AND LEASE ........     60
     Section 12.1 Company May Consolidate, Etc., on Certain Terms .......     60
     Section 12.2 Successor Corporation to be Substituted ...............     60
     Section 12.3 Opinion of Counsel to be Given Trustee ................     61
ARTICLE THIRTEEN SATISFACTION AND DISCHARGE OF INDENTURE ................     61
     Section 13.1 Discharge of Indenture ................................     61
     Section 13.2 Deposited Monies to be Held in Trust by Trustee .......     62
     Section 13.3 Paying Agent to Repay Monies Held .....................     62
     Section 13.4 Return of Unclaimed Monies ............................     62
     Section 13.5 Reinstatement .........................................     62
ARTICLE FOURTEEN IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS
 AND DIRECTORS ..........................................................     62
     Section 14.1 Indenture and Notes Solely Corporate Obligations ......     62
ARTICLE FIFTEEN CONVERSION OF NOTES .....................................     63
     Section 15.1 Right to Convert ......................................     63
     Section 15.2 Exercise of Conversion Privilege; Issuance of Common
                  Stock or Cash on Conversion; No Adjustment for
                  Interest or Dividends .................................     63
     Section 15.3 Cash Payments in Lieu of Fractional Shares ............     66
     Section 15.4 Conversion Price 66 Section 15.5 Adjustment of
                  Conversion Rate .......................................     66
     Section 15.6 Effect of Reclassification, Consolidation, Merger
                  or Sale ...............................................     75
     Section 15.7 Taxes on Shares Issued ................................     76
     Section 15.8 Reservation of Shares; Shares to be Fully Paid;
                  Compliance with Governmental Requirements; Listing
                  of Common Stock .......................................     76
     Section 15.9 Responsibility of Trustee .............................     77
     Section 15.10 Notice to Holders Prior to Certain Actions ...........     78
ARTICLE SIXTEEN MISCELLANEOUS PROVISIONS ................................     79
     Section 16.1 Provisions Binding on Company's Successors ............     79
     Section 16.2 Official Acts by Successor Corporation ................     79
</TABLE>


                                      -v-

<PAGE>

                                TABLE OF CONTENTS
                                  (continued)
<TABLE>
<CAPTION>
                                                                            Page
                                                                            ----
<S>                                                                         <C>
    Section 16.3  Addresses for Notices, Etc ............................     79
    Section 16.4  Governing Law .........................................     79
    Section 16.5  Evidence of Compliance with Conditions Precedent;
                  Certificates to Trustee ...............................     79
    Section 16.6  Legal Holidays ........................................     80
    Section 16.7  Trust Indenture Act ...................................     80
    Section 16.8  No Security Interest Created ..........................     80
    Section 16.9  Benefits of Indenture .................................     80
    Section 16.10 Table of Contents, Headings, Etc ......................     81
    Section 16.11 Authenticating Agent ..................................     81
    Section 16.12 Execution in Counterparts .............................     82
    Section 16.13 Severability ..........................................     82
</TABLE>

                                      -vi-


<PAGE>

     Reconciliation and Tie Between the Trust Indenture Act of 1939 and
Indenture, dated as of November 21, 2001, between Riverstone Networks, Inc. and
State Street Bank and Trust Company of California, N.A., as Trustee.

<TABLE>
<CAPTION>
<S>                                                                <C>
    TRUST INDENTURE ACT SECTION                                    INDENTURE SECTION
    Section 310  (a)(1) ......................................     8.9
                 (a)(2) ......................................     8.9
                 (a)(3) ......................................     Not Applicable
                 (a)(4) ......................................     Not Applicable
                 (a)(5) ......................................     8.9
                 (b) .........................................     8.8; 8.9; 8.10; 8.11
    Section 311  (a) .........................................     8.13
                 (b) .........................................     8.13
                 (b)(2) ......................................     8.13
    Section 312  (a) .........................................     6.1; 6.2(a)
                 (b) .........................................     6.2(b)
                 (c) .........................................     6.2(c)
    Section 313  (a) .........................................     6.3(a)
                 (b) .........................................     6.3(a)
                 (c) .........................................     6.3(a)
                 (d) .........................................     6.3(b)
    Section 314  (a) .........................................     6.4
                 (b) .........................................     Not Applicable
                 (c)(1) ......................................     16.5
                 (c)(2) ......................................     16.5
                 (c)(3) ......................................     Not Applicable
                 (d) .........................................     Not Applicable
                 (e) .........................................     16.5
    Section 315  (a) .........................................     8.1
                 (b) .........................................     7.8
                 (c) .........................................     8.1
                 (d) .........................................     8.1
                 (d)(1) ......................................     8.1(a)
                 (d)(2) ......................................     8.1(b)
                 (d)(3) ......................................     8.1(c)
                 (e) .........................................     7.9
    Section 316  (a) .........................................     7.7
                 (a)(1)(A) ...................................     7.7
                 (a)(1)(B) ...................................     7.7
                 (a)(2) ......................................     Not Applicable
                 (b) .........................................     7.4
</TABLE>

                                     -vii-

<PAGE>

<TABLE>
<CAPTION>
<S>                                                                <C>
                 (c) .........................................     9.1
    Section 317  (a)(1) ......................................     7.5
                 (a)(2) ......................................     7.5
                 (b) .........................................     5.4
    Section 318  (a) .........................................     16.7
</TABLE>


     Note: This reconciliation and tie shall not, for any purpose, be deemed to
be a part of the Indenture.


                                     -viii-


<PAGE>

                                    INDENTURE

     INDENTURE, dated as of November 21, 2001, between Riverstone Networks,
Inc., a Delaware corporation (hereinafter called the "Company") having its
principal office at 5200 Great America Parkway, Santa Clara, California 95054,
and State Street Bank and Trust Company of California, N.A., a national banking
association, as trustee hereunder (hereinafter called the "Trustee") having its
principal corporate trust office at 633 West 5th Street, 12th Floor, Los
Angeles, California 90071.

                              W I T N E S S E T H :
                              - - - - - - - - - -

     WHEREAS, for its lawful corporate purposes, the Company has duly authorized
the issue of its 3 3/4% Convertible Subordinated Notes due 2006 (hereinafter
called the "Notes"), in an aggregate principal amount not to exceed $175,000,000
and, to provide the terms and conditions upon which the Notes are to be
authenticated, issued and delivered, the Company has duly authorized the
execution and delivery of this Indenture; and

     WHEREAS, the Notes, the certificate of authentication to be borne by the
Notes, a form of assignment, a form of option to elect repayment upon a
Fundamental Change, and a form of conversion notice to be borne by the Notes are
to be substantially in the forms hereinafter provided for; and

     WHEREAS, all acts and things necessary to make the Notes, when executed by
the Company and authenticated and delivered by the Trustee or a duly authorized
authenticating agent, as in this Indenture provided, the valid, binding and
legal obligations of the Company, and to constitute these presents a valid
agreement according to its terms, have been done and performed, and the
execution of this Indenture and the issue hereunder of the Notes have in all
respects been duly authorized.

     NOW, THEREFORE, THIS INDENTURE WITNESSETH:

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

                                      A-1

<PAGE>

                                   ARTICLE ONE

                                   DEFINITIONS

     Section 1.1 Definitions. The terms defined in this Section 1.1 (except as
                 -----------
herein otherwise expressly provided or unless the context otherwise requires)
for all purposes of this Indenture and of any indenture supplemental hereto
shall have the respective meanings specified in this Section 1.1. All other
terms used in this Indenture that are defined in the Trust Indenture Act or
which are by reference therein defined in the Securities Act (except as herein
otherwise expressly provided or unless the context otherwise requires) shall
have the meanings assigned to such terms in said Trust Indenture Act and in said
Securities Act as in force at the date of the execution of this Indenture. The
words "herein", "hereof", "hereunder", and words of similar import refer to this
Indenture as a whole and not to any particular Article, Section or other
Subdivision. The terms defined in this Article include the plural as well as the
singular.

     "Affiliate" of any specified Person means any other Person directly or
      ---------
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person. For the purposes of this definition,
"control", when used with respect to any specified Person means the power to
direct or cause the direction of the management and policies of such Person,
directly or indirectly, whether through the ownership of voting securities, by
contract or otherwise, and the terms "controlling" and "controlled" have
meanings correlative to the foregoing. "Board of Directors" means the Board of
Directors of the Company or a committee of such Board duly authorized to act for
it hereunder.

     "Business Day" means each Monday, Tuesday, Wednesday, Thursday and Friday
      ------------
which is not a day on which the banking institutions in The City of New York or
the city in which the Corporate Trust Office is located are authorized or
obligated by law or executive order to close or be closed.

     "Cash Conversion Notice" has the meaning specified in Section 15.2.
      ----------------------
"Closing Price" has the meaning specified in Section 15.5(h)(1).

     "Commission" means the Securities and Exchange Commission, as from time to
      ----------
time constituted, created under the Exchange Act, or, if at any time after the
execution of this Indenture such Commission is not existing and performing the
duties now assigned to it under the Trust Indenture Act, then the body
performing such duties at such time. "Common Stock" means any stock of any class
of the Company which has no preference in respect of dividends or of amounts
payable in the event of any voluntary or involuntary liquidation, dissolution or
winding up of the Company and which is not subject to redemption by the Company.
Subject to the provisions of Section 15.6, however, shares issuable on
conversion of Notes shall include only shares of the class designated as common
stock of the Company at the date of this

                                      -2-

<PAGE>

Indenture (namely, the Common Stock, par value $0.01 per share) or shares of any
class or classes resulting from any reclassification or reclassifications
thereof and which have no preference in respect of dividends or of amounts
payable in the event of any voluntary or involuntary liquidation, dissolution or
winding up of the Company and which are not subject to redemption by the
Company; provided, however, that if at any time there shall be more than one
such resulting class, the shares of each such class then so issuable shall be
substantially in the proportion which the total number of shares of such class
resulting from all such reclassifications bears to the total number of shares of
all such classes resulting from all such reclassifications.

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

     "Company Notice" has the meaning specified in Section 3.5(b).
      --------------

     "Conversion Date" has the meaning specified in Section 15.2.
      ---------------

     "Conversion Price" has the meaning specified in Section 3.1(a).
      ----------------

     "Conversion Rate" has the meaning specified in Section 15.4.
      ---------------

     "Corporate Trust Office" or other similar term, means the designated office
      ----------------------
of the Trustee at which at any particular time the trust created by this
Indenture shall be administered, which office is, at the date as of which this
Indenture is dated, located at 633 West 5th Street, 12th Floor, Los Angeles,
California 90071, attention: Corporate Trust Department (Riverstone Networks,
Inc. 3 3/4% Convertible Subordinated Notes due 2006).

     "Custodian" means State Street Bank and Trust Company of California, N.A.,
      ---------
as custodian with respect to the Notes in global form, or any successor entity
thereto.

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

     "Defaulted Interest" has the meaning specified in Section 2.3.
      ------------------

     "Depositary" means, with respect to the Notes issuable or issued in whole
      ----------
or in part in global form, the Person specified in Section 2.5(d) as the
Depositary with respect to such Notes, until a successor shall have been
appointed and become such pursuant to the applicable provisions of this
Indenture, and thereafter, "Depositary" shall mean or include such successor.

     "Designated Senior Indebtedness" means any Senior Indebtedness with respect
      ------------------------------
to which the instrument creating or evidencing the same or the assumption or
guarantee thereof (or related agreements or documents to which the Company is a
party) expressly provides that such Senior Indebtedness shall be "Designated
Senior Indebtedness" for purposes of this Indenture (provided that such
instrument, agreement or other document may place limitations and conditions on
the right of such Senior Indebtedness to exercise the rights of Designated
Senior Indebtedness). If any payment

                                      -3-

<PAGE>

made to any holder of any Designated Senior Indebtedness or its Representative
with respect to such Designated Senior Indebtedness is rescinded or must
otherwise be returned by such holder or Representative upon the insolvency,
bankruptcy or reorganization of the Company or otherwise, the reinstated
Indebtedness of the Company arising as a result of such rescission or return
shall constitute Designated Senior Indebtedness effective as of the date of such
rescission or return.

     "Event of Default" means any event specified in Section 7.1(a), (b), (c),
      ----------------
d) or (e).

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

     "Fundamental Change" means the occurrence of any transaction or event in
      ------------------
connection with which all or substantially all of the Common Stock shall be
exchanged for, converted into, acquired for or constitute solely the right to
receive consideration (whether by means of an exchange offer, liquidation,
tender offer, consolidation, merger, combination, reclassification,
recapitalization or otherwise) which is not all or substantially all common
stock listed (or, upon consummation of or immediately following such transaction
or event, which will be listed) on a United States national securities exchange
or approved (or upon consummation of or immediately following such transaction
or event, which will be approved) for quotation on the Nasdaq National Market or
any similar United States system of automated dissemination of quotations of
securities prices.

     "Global Note" has the meaning set forth in Section 2.5(b).
      -----------

     "Indebtedness" means, with respect to any Person, and without duplication:
      ------------
(a) all indebtedness, obligations and other liabilities (contingent or
otherwise) of such Person for borrowed money (including obligations of the
Company in respect of overdrafts, foreign exchange contracts, currency exchange
agreements, interest rate protection agreements, and any loans or advances from
banks, whether or not evidenced by notes or similar instruments) or evidenced by
bonds, debentures, notes or similar instruments (whether or not the recourse of
the lender is to the whole of the assets of such Person or to only a portion
thereof), other than any account payable or other accrued current liability or
obligation 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) 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 and all obligations and other liabilities (contingent or otherwise) under
any lease or related document (including a purchase agreement) in connection
with the lease of real property which provides that such Person is contractually
obligated to purchase or cause a third party to purchase the leased property and
thereby guarantee a minimum residual value of the leased property to the 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; (d) all
obligations of such Person (contingent or otherwise) with respect to an interest
rate or other swap, cap or collar agreement or other similar instrument or
agreement or foreign currency hedge, exchange, purchase or similar instrument or
agreement; (e) all direct or indirect guaranties or similar agreements by such
Person in respect of, and obligations or liabilities (contingent or otherwise)
of such Person to

                                      -4-

<PAGE>

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

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

     "Initial Purchasers" means Morgan Stanley & Co. Incorporated and Salomon
      ------------------
Smith Barney Inc.

     "Institutional Accredited Investor" means an institutional "accredited
      ---------------------------------
investor" within the meaning of Rule 501(a)(1), (2), (3) or (7) under the
Securities Act.

     "Liquidated Damages" has the meaning specified for "Liquidated Damages
      ------------------
Amount" in Section 2(e) of the Registration Rights Agreement.

     "Make-Whole Payment" has the meaning specified in Section 4.1(a).
      ------------------

     "New Rights Plan" has the meaning specified in Section 15.5(d).
      ---------------

     "Non-Payment Default" has the meaning specified in Section 4.2(ii).
      -------------------

     "Non-Provisional Redemption" has the meaning specified in Section 3.1(b).
      --------------------------

     "Note" or "Notes" means any Note or Notes, as the case may be,
      ----      -----
authenticated and delivered under this Indenture, including the Global Note.

     "Note register" has the meaning specified in Section 2.5(a).
      -------------

     "Note registrar" has the meaning specified in Section 2.5(a).
      --------------

     "Noteholder" or "holder" as applied to any Note, or other similar terms
      ----------      ------
(but excluding the term "beneficial holder"), means any Person in whose name at
the time a particular Note is registered on the Note registrar's books.

     "Notice Date" has the meaning specified in Section 3.1(b).
      -----------

     "Officers' Certificate", when used with respect to the Company, means a
      ---------------------
certificate signed by both (a) the Chairman of the Board, the Chief Executive
Officer, the President or any Vice President (whether or not designated by a
number or numbers or word or words added before or after

                                      -5-

<PAGE>

the title "Vice President") and (b) the Treasurer or any Assistant Treasurer,
the Controller or any Assistant Controller, or the Secretary or any Assistant
Secretary of the Company.

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

     "outstanding", when used with reference to Notes and subject to the
      -----------
provisions of Section 9.4, means, as of any particular time, all Notes
authenticated and delivered by the Trustee under this Indenture, except:

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

          (b) Notes, or portions thereof, (i) for the redemption of which monies
     in the necessary amount shall have been deposited in trust with the Trustee
     or with any paying agent (other than the Company) or (ii) which shall have
     been otherwise defeased in accordance with Article Thirteen;

          (c) Notes in lieu of which, or in substitution for which, other Notes
     shall have been authenticated and delivered pursuant to the terms of
     Section 2.6; and

          (d) Notes converted into Common Stock pursuant to Article Fifteen and
     Notes deemed not outstanding pursuant to Article Three.

     "Payment Blockage Notice" has the meaning specified in Section 4.2(ii).
      -----------------------

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

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

     "Predecessor Note" of any particular Note means every previous Note
      ----------------
evidencing all or a portion of the same debt as that evidenced by such
particular Note, and, for the purposes of this definition, any Note
authenticated and delivered under Section 2.6 in lieu of a lost, destroyed or
stolen Note shall be deemed to evidence the same debt as the lost, destroyed or
stolen Note that it replaces.

     "Provisional Redemption" has the meaning specified in Section 3.1(a).
      ----------------------

     "Provisional Redemption Date" means the date on which the Notes are
      ---------------------------
redeemed pursuant to a Provisional Redemption.

     "Purchased Shares" has the meaning specified in Section 15.5(f).
      ----------------

                                      -6-


<PAGE>

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

     "Registration Rights Agreement" means that certain Registration Rights
      -----------------------------
Agreement, dated as of November 21, 2001, among the Company and the Initial
Purchasers, as amended from time to time in accordance with its terms.

     "Representative" means (a) the indenture trustee or other trustee, agent or
      --------------
representative for any Senior Indebtedness or (b) with respect to any Senior
Indebtedness that does not have any such trustee, agent or other representative,
(i) in the case of such Senior Indebtedness issued pursuant to an agreement
providing for voting arrangements as among the holders or owners of such Senior
Indebtedness, any holder or owner of such Senior Indebtedness acting with the
consent of the required Persons necessary to bind such holders or owners of such
Senior Indebtedness and (ii) in the case of all other such Senior Indebtedness,
the holder or owner of such Senior Indebtedness.

     "Responsible Officer", when used with respect to the Trustee, means an
      -------------------
officer of the Trustee in the Corporate Trust Office assigned and duly
authorized by the Trustee to administer this Indenture.

     "Restricted Securities" has the meaning specified in Section 2.5(d).
      ---------------------

     "Rights Agreement" has the meaning specified in Section 15.5(d).
      ----------------

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

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

     "Senior Indebtedness" means the principal of, premium, if any, interest
      -------------------
(including all interest accruing subsequent to the commencement of any
bankruptcy or similar proceeding, whether or not a claim for post-petition
interest is allowable as a claim in any such proceeding) and rent payable on or
in connection with, and all fees, costs, expenses and other amounts accrued or
due on or in connection with, Indebtedness of the Company, whether outstanding
on the date of this Indenture or thereafter created, incurred, assumed,
guaranteed or in effect guaranteed by the Company (including all deferrals,
renewals, extensions or refundings of, or amendments, modifications or
supplements to, the foregoing), unless in the case of any particular
Indebtedness the instrument creating or evidencing the same or the assumption or
guarantee thereof expressly provides that such Indebtedness shall not be senior
in right of payment to the Notes or expressly provides that such Indebtedness is
"pari passu" or "junior" to the Notes. Notwithstanding the foregoing, the term
"Senior Indebtedness" shall not include any Indebtedness of the Company to any
subsidiary of the Company, a majority of the voting stock of which is owned,
directly or indirectly, by the Company. If any payment made to any holder of any
Senior Indebtedness or its Representative with respect to such Senior
Indebtedness is rescinded or must otherwise be returned by such holder or
Representative upon the insolvency, bankruptcy or reorganization of the Company
or otherwise, the reinstated Indebtedness of the Company arising as a result of
such rescission or return shall constitute Senior Indebtedness effective as of
the date of such rescission or return.

                                      -7-


<PAGE>

     "Significant Subsidiary" means, as of any date of determination, a
      ----------------------
Subsidiary of the Company that would constitute a "significant subsidiary" as
such term is defined under Rule 1-02 of Regulation S-X of the Commission.

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

     "Trading Day" has the meaning specified in Section 15.5(h)(5).
      -----------

     "Trigger Event" has the meaning specified in Section 15.5(d).
      -------------

     "Trust Indenture Act" means the Trust Indenture Act of 1939, as amended, as
      -------------------
it was in force at the date of this Indenture, except as provided in Sections
11.3 and 15.6; provided, however, that, in the event the Trust Indenture Act of
1939 is amended after the date hereof, the term "Trust Indenture Act" shall
mean, to the extent required by such amendment, the Trust Indenture Act of 1939
as so amended.

     "Trustee" means State Street Bank and Trust Company of California, N.A.,
      -------
and its successors and any corporation resulting from or surviving any
consolidation or merger to which it or its successors may be a party and any
successor trustee at the time serving as successor trustee hereunder.

     The definitions of certain other terms are as specified in Sections 2.5 and
3.5 and Article Fifteen.



                                  ARTICLE TWO

                         ISSUE, DESCRIPTION, EXECUTION,
                       REGISTRATION AND EXCHANGE OF NOTES

     Section 2.1 Designation Amount and Issue of Notes. The Notes shall be
                 -------------------------------------
designated as "3 3/4% Convertible Subordinated Notes due 2006". Notes not to
exceed the aggregate principal amount of $175,000,000 (except pursuant to
Sections 2.5, 2.6, 3.3, 3.5 and 15.2 hereof) upon the execution of this
Indenture, or from time to time thereafter, may be executed by the Company and
delivered to the Trustee for authentication, and the Trustee shall thereupon
authenticate and deliver said Notes to or upon the written order of the Company,
signed by (a) its Chairman of the Board, Chief Executive Officer, President or
any Vice President (whether or not designated by a number or numbers or word or
words added before or after the title "Vice President") and (b) its Treasurer or
any Assistant

                                      -8-

<PAGE>

Treasurer, its Controller or any Assistant Controller or its Secretary or any
Assistant Secretary, without any further action by the Company hereunder.

     Section 2.2 Form of Notes. The Notes and the Trustee's certificate of
                 -------------
authentication to be borne by such Notes shall be substantially in the form set
forth in Exhibit A, which is incorporated in and made a part of this Indenture.

     Any of the Notes may have such letters, numbers or other marks of
identification and such notations, legends and endorsements as the officers
executing the same may approve (execution thereof to be conclusive evidence of
such approval) and as are not inconsistent with the provisions of this
Indenture, or as may be required to comply with any law or with any rule or
regulation made pursuant thereto or with any rule or regulation of any
securities exchange or automated quotation system on which the Notes may be
listed, or to conform to usage.

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

     The terms and provisions contained in the form of Note attached as Exhibit
A hereto shall constitute, and are hereby expressly made, a part of this
Indenture and, to the extent applicable, the Company and the Trustee, by their
execution and delivery of this Indenture, expressly agree to such terms and
provisions and to be bound thereby.

     Section 2.3 Date and Denomination of Notes; Payments of Interest. The Notes
                 ----------------------------------------------------
shall be issuable in registered form without coupons in denominations of $1,000
principal amount and integral multiples thereof. Every Note shall be dated the
date of its authentication and shall bear interest from the applicable date in
each case as specified on the face of the form of Note attached as Exhibit A
hereto. Interest on the Notes shall be computed on the basis of a 360-day year
comprised of twelve (12) 30-day months.

     The Person in whose name any Note (or its Predecessor Note) is registered
on the Note register at the close of business on any record date with respect to
any interest payment date shall be entitled to receive the interest payable on
such interest payment date, except (i) that the interest payable upon redemption
(unless the date of redemption is an interest payment date) will be payable to
the Person to whom principal is payable and (ii) as set forth in the next
succeeding sentence. In the case of any Note (or portion thereof) that is
converted during the period from (but excluding) a record date to (but
excluding) the next succeeding interest payment date either (x) if such Note (or
portion thereof) has been called for redemption on a redemption date which
occurs during such period, or is to be redeemed in connection with a Fundamental
Change on a Repurchase Date (as

                                      -9-

<PAGE>

defined in Section 3.5) that occurs during such period, the Company shall not be
required to pay interest on such interest payment date in respect of any such
Note (or portion thereof) except to the extent required to be paid upon
redemption of such Note or portion thereof pursuant to Section 3.3 or 3.5 hereof
or (y) if such Note (or portion thereof) has not been called for redemption on a
redemption date that occurs during such period and is not to be redeemed in
connection with a Fundamental Change on a Repurchase Date that occurs during
such period, such Note (or portion thereof) that is submitted for conversion
during such period shall be accompanied by funds equal to the interest payable
on such succeeding interest payment date on the principal amount so converted,
as provided in the penultimate paragraph of Section 15.2 hereof, unless at the
time of conversion there is a default in the payment of interest on the Notes.
Interest shall be payable at the office of the Company maintained by the Company
for such purposes in the Borough of Manhattan, The City of New York, which shall
initially be an office or agency of the Trustee and may, as the Company shall
specify to the paying agent in writing by each record date, be paid either (i)
by check mailed to the address of the Person entitled thereto as it appears in
the Note register (provided that the holder of Notes with an aggregate principal
amount in excess of $2,000,000 shall, at the written election of such holder, be
paid by wire transfer in immediately available funds) or (ii) by transfer to an
account maintained by such Person located in the United States; provided,
however, that payments to the Depositary will be made by wire transfer of
immediately available funds to the account of the Depositary or its nominee. The
term "record date" with respect to any interest payment date shall mean the May
15 or November 15 preceding the relevant June 1 or December 1, respectively.

     Any interest on any Note which is payable, but is not punctually paid or
duly provided for, on any June 1 or November 1 (herein called "Defaulted
Interest") shall forthwith cease to be payable to the Noteholder on the relevant
record date by virtue of his having been such Noteholder, and such Defaulted
Interest shall be paid by the Company, at its election in each case, as provided
in clause (1) or (2) below:

          (1) The Company may elect to make payment of any Defaulted Interest to
     the Persons in whose names the Notes (or their respective Predecessor
     Notes) are registered at the close of business on a special record date for
     the payment of such Defaulted Interest, which shall be fixed in the
     following manner. The Company shall notify the Trustee in writing of the
     amount of Defaulted Interest to be paid on each Note and the date of the
     payment (which shall be not less than twenty-five (25) days after the
     receipt by the Trustee of such notice, unless the Trustee shall consent to
     an earlier date), and at the same time the Company shall deposit with the
     Trustee an amount of money equal to the aggregate amount to be paid in
     respect of such Defaulted Interest or shall make arrangements satisfactory
     to the Trustee for such deposit prior to the date of the proposed payment,
     such money when deposited to be held in trust for the benefit of the Person
     entitled to such Defaulted Interest as in this clause provided. Thereupon
     the Trustee shall fix a special record date for the payment of such
     Defaulted Interest which shall be not more than fifteen (15) days and not
     less than ten (10) days prior to the date of the proposed payment, and not
     less than ten (10) days after the receipt by the Trustee of the notice of
     the proposed payment, the Trustee shall promptly notify the Company of such
     special record date and, in the name and at the expense of the Company,
     shall cause notice of the proposed payment of such Defaulted Interest and
     the

                                      -10-

<PAGE>

     special record date therefor to be mailed, first-class postage prepaid, to
     each Noteholder at his address as it appears in the Note register, not less
     than ten (10) days prior to such special record date. Notice of the
     proposed payment of such Defaulted Interest and the special record date
     therefor having been so mailed, such Defaulted Interest shall be paid to
     the Persons in whose names the Notes (or their respective Predecessor
     Notes) were registered at the close of business on such special record date
     and shall no longer be payable pursuant to the following clause (2) of this
     Section 2.3.

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

     Section 2.4 Execution of Notes. The Notes shall be signed in the name and
                 ------------------
on behalf of the Company by the manual or facsimile signature of its Chairman of
the Board, Chief Executive Officer, President or any Vice President (whether or
not designated by a number or numbers or word or words added before or after the
title "Vice President") and attested by the manual or facsimile signature of its
Secretary or any of its Assistant Secretaries or its Treasurer or any of its
Assistant Treasurers (which may be printed, engraved or otherwise reproduced
thereon, by facsimile or otherwise). Only such Notes as shall bear thereon a
certificate of authentication substantially in the form set forth on the form of
Note attached as Exhibit A hereto, manually executed by the Trustee (or an
authenticating agent appointed by the Trustee as provided by Section 16.11),
shall be entitled to the benefits of this Indenture or be valid or obligatory
for any purpose. Such certificate by the Trustee (or such an authenticating
agent) upon any Note executed by the Company shall be conclusive evidence that
the Note so authenticated has been duly authenticated and delivered hereunder
and that the holder is entitled to the benefits of this Indenture.

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

     Section 2.5 Exchange and Registration of Transfer Notes; Restrictions on
                 ------------------------------------------------------------
Transfer; Depositary.
--------------------

          (a) The Company shall cause to be kept at the Corporate Trust Office a
register (the register maintained in such office and in any other office or
agency of the Company designated pursuant to Section 5.2 being herein sometimes
collectively referred to as the "Note register") in which, subject to such
reasonable regulations as it may prescribe, the Company shall provide for the
registration of Notes and of transfers of Notes. The Note register shall be in
written form or in any

                                      -11-

<PAGE>

form capable of being converted into written form within a reasonably prompt
period of time. The Trustee is hereby appointed "Note registrar" for the purpose
of registering Notes and transfers of Notes as herein provided. The Company may
appoint one or more co-registrars in accordance with Section 5.2.

     Upon surrender for registration of transfer of any Note to the Note
registrar or any co-registrar, and satisfaction of the requirements for such
transfer set forth in this Section 2.5, the Company shall execute, and the
Trustee shall authenticate and deliver, in the name of the designated transferee
or transferees, one or more new Notes of any authorized denominations and of a
like aggregate principal amount and bearing such restrictive legends as may be
required by this Indenture.

     Notes may be exchanged for other Notes of any authorized denominations and
of a like aggregate principal amount, upon surrender of the Notes to be
exchanged at any such office or agency maintained by the Company pursuant to
Section 5.2. Whenever any Notes are so surrendered for exchange, the Company
shall execute, and the Trustee shall authenticate and deliver, the Notes which
the Noteholder making the exchange is entitled to receive bearing registration
numbers not contemporaneously outstanding.

     All Notes issued upon any registration of transfer or exchange of Notes
shall be the 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.

     All Notes presented or surrendered for registration of transfer or for
exchange, redemption or conversion shall (if so required by the Company or the
Note registrar) be duly endorsed, or be accompanied by a written instrument or
instruments of transfer in form satisfactory to the Company, and the Notes shall
be duly executed by the Noteholder thereof or his attorney duly authorized in
writing.

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

     Neither the Company nor the Trustee nor any Note registrar shall be
required to exchange or register a transfer of (a) any Notes for a period of
fifteen (15) days next preceding any selection of Notes to be redeemed, (b) any
Notes or portions thereof called for redemption pursuant to Section 3.2, (c) any
Notes or portions thereof surrendered for conversion pursuant to Article Fifteen
or (d) any Notes or portions thereof tendered for redemption (and not withdrawn)
pursuant to Section 3.5.

          (b) So long as the Notes are eligible for book-entry settlement with
the Depositary, or unless otherwise required by law, all Notes that, upon
initial issuance are beneficially owned by QIBs or as a result of a sale or
transfer after initial issuance are beneficially owned by QIBs, will be
represented by one or more Notes in global form registered in the name of the
Depositary or the

                                      -12-

<PAGE>

nominee of the Depositary (the "Global Note"), except as otherwise specified
below. The transfer and exchange of beneficial interests in any such Global Note
shall be effected through the Depositary in accordance with this Indenture and
the procedures of the Depositary therefor. The Trustee shall make appropriate
endorsements to reflect increases or decreases in the principal amounts of any
such Global Note as set forth on the face of the Note ("Principal Amount") to
reflect any such transfers. Except as provided below, beneficial owners of a
Global Note shall not be entitled to have certificates registered in their
names, will not receive or be entitled to receive physical delivery of
certificates in definitive form and will not be considered holders of such
Global Note.

          (c) So long as the Notes are eligible for book-entry settlement with
the Depositary, or unless otherwise required by law, upon any transfer of a
definitive Note to a QIB in accordance with Rule 144A, and upon receipt of the
definitive Note or Notes being so transferred, together with a certification,
substantially in the form on the reverse of the Note, from the transferor that
the transfer is being made in compliance with Rule 144A (or other evidence
satisfactory to the Trustee), the Trustee shall make an endorsement on the
Global Note to reflect an increase in the aggregate Principal Amount of the
Notes represented by such Global Note, and the Trustee shall cancel such
definitive Note or Notes in accordance with the standing instructions and
procedures of the Depositary, the aggregate Principal Amount of the Notes
represented by such Global Note to be increased accordingly; provided, however,
that no definitive Note, or portion thereof, in respect of which the Company or
an Affiliate of the Company held any beneficial interest shall be included in
such Global Note until such definitive Note is freely tradable in accordance
with Rule 144(k) under the Securities Act, provided further that the Trustee
shall issue Notes in definitive form upon any transfer of a beneficial interest
in the Global Note to the Company or any Affiliate of the Company.

     Upon any sale or transfer of a Note to an Institutional Accredited Investor
(other than pursuant to a registration statement that has been declared
effective under the Securities Act), such Institutional Accredited Investor
shall, prior to such sale or transfer, furnish to the Company and/or the Trustee
a signed letter containing representations and agreements relating to
restrictions on transfer substantially in the form set forth in Exhibit B to
this Indenture. Upon any transfer of a beneficial interest in the Global Note to
an Institutional Accredited Investor, the Trustee shall make an endorsement on
the Global Note to reflect a decrease in the aggregate Principal Amount of the
Notes represented by such Global Note, and the Company shall execute a
definitive Note or Notes in exchange therefore, and the Trustee, upon receipt of
such definitive Note or Notes and the written order of the Company, shall
authenticate and deliver such, definitive Note or Notes.

     Any Note in global form may be endorsed with or have incorporated in the
text thereof such legends or recitals or changes not inconsistent with the
provisions of this Indenture as may be required by the Custodian, the Depositary
or by the National Association of Securities Dealers, Inc. in order for the
Notes to be tradeable on The Portal Market or as may be required for the Notes
to be tradeable on any other market developed for trading of securities pursuant
to Rule 144A or required to comply with any applicable law or any regulation
thereunder or with the rules and regulations of any securities exchange or
automated quotation system upon which the Notes may be listed or traded

                                      -13-

<PAGE>

or to conform with any usage with respect thereto, or to indicate any special
limitations or restrictions to which any particular Notes are subject.

          (d) Every Note that bears or is required under this Section 2.5(d) to
bear the legend set forth in this Section 2.5(d) (together with any Common Stock
issued upon conversion of the Notes and required to bear the legend set forth in
Section 2.5(e), collectively, the "Restricted Securities") shall be subject to
the restrictions on transfer set forth in this Section 2.5(d) (including those
set forth in the legend set forth below) unless such restrictions on transfer
shall be waived by written consent of the Company, and the holder of each such
Restricted Security, by such Noteholder's acceptance thereof, agrees to be bound
by all such restrictions on transfer. As used in Sections 2.5(d) and 2.5(e), the
term "transfer" encompasses any sale, pledge, loan, transfer or other
disposition whatsoever of any Restricted Security.

     Until the expiration of the holding period applicable to sales thereof
under Rule 144(k) under the Securities Act (or any successor provision), any
certificate evidencing such Note (and all securities issued in exchange therefor
or substitution thereof, other than Common Stock, if any, issued upon conversion
thereof, which shall bear the legend set forth in Section 2.5(e), if applicable)
shall bear a legend in substantially the following form, unless such Note has
been sold pursuant to a registration statement that has been declared effective
under the Securities Act (and which continues to be effective at the time of
such transfer), or unless otherwise agreed by the Company in writing, with
written notice thereof to the Trustee:

     THE NOTE EVIDENCED HEREBY HAS NOT BEEN REGISTERED UNDER THE UNITED STATES
     SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE
     SECURITIES LAWS, AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD WITHIN THE
     UNITED STATES OR TO, OR FOR THE ACCOUNT OR BENEFIT OF, UNITED STATES
     PERSONS EXCEPT AS SET FORTH IN THE FOLLOWING SENTENCE. BY ITS ACQUISITION
     HEREOF, THE HOLDER (1) REPRESENTS THAT IT IS (A) A "QUALIFIED INSTITUTIONAL
     BUYER" (AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT), (B) AN
     INSTITUTIONAL "ACCREDITED INVESTOR" (AS DEFINED IN RULE 501(A)(1), (2), (3)
     OR (7) UNDER THE SECURITIES ACT) ("INSTITUTIONAL ACCREDITED INVESTOR"), OR
     (C) A NON-U.S. PERSON; (2) AGREES THAT IT WILL NOT, PRIOR TO EXPIRATION OF
     THE HOLDING PERIOD APPLICABLE TO SALES OF THE NOTE EVIDENCED HEREBY UNDER
     RULE 144(K) UNDER THE SECURITIES ACT (OR ANY SUCCESSOR PROVISION), RESELL
     OR OTHERWISE TRANSFER THIS NOTE OR THE COMMON STOCK ISSUABLE UPON
     CONVERSION OF THIS NOTE EXCEPT (A) TO RIVERSTONE NETWORKS, INC. OR ANY
     SUBSIDIARY THEREOF, (B) INSIDE THE UNITED STATES TO A QUALIFIED
     INSTITUTIONAL BUYER IN COMPLIANCE WITH RULE 144A UNDER THE SECURITIES ACT,
     (C) INSIDE THE UNITED STATES TO AN INSTITUTIONAL ACCREDITED INVESTOR THAT,
     PRIOR TO SUCH TRANSFER, FURNISHES TO STATE STREET BANK AND TRUST COMPANY OF
     CALIFORNIA, N.A.,

                                      -14-

<PAGE>

     AS TRUSTEE (OR A SUCCESSOR TRUSTEE, AS APPLICABLE), A SIGNED LETTER
     CONTAINING CERTAIN REPRESENTATIONS AND AGREEMENTS RELATING TO THE
     RESTRICTIONS ON TRANSFER OF THE NOTES (THE FORM OF WHICH LETTER CAN BE
     OBTAINED FROM SUCH TRUSTEE OR A SUCCESSOR TRUSTEE, AS APPLICABLE), AND IF
     SUCH TRANSFER IS IN RESPECT OF AN AGGREGATE PRINCIPAL AMOUNT OF NOTES OF
     LESS THAN $100,000, AN OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY THAT
     SUCH TRANSFER IS IN COMPLIANCE WITH THE SECURITIES ACT, (D) OUTSIDE THE
     UNITED STATES IN COMPLIANCE WITH RULE 904 UNDER THE SECURITIES ACT, (E)
     PURSUANT TO THE EXEMPTION FROM REGISTRATION PROVIDED BY RULE 144 UNDER THE
     SECURITIES ACT (IF AVAILABLE) OR (F) PURSUANT TO A REGISTRATION STATEMENT
     WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT (AND WHICH
     CONTINUES TO BE EFFECTIVE AT THE TIME OF SUCH TRANSFER); (3) PRIOR TO SUCH
     TRANSFER (OTHER THAN A TRANSFER PURSUANT TO CLAUSE (2)(F) ABOVE), IT WILL
     FURNISH TO STATE STREET BANK AND TRUST COMPANY OF CALIFORNIA, N.A., AS
     TRUSTEE (OR A SUCCESSOR TRUSTEE, AS APPLICABLE), SUCH CERTIFICATIONS, LEGAL
     OPINIONS OR OTHER INFORMATION AS THE TRUSTEE MAY REASONABLY REQUIRE TO
     CONFIRM THAT SUCH TRANSFER IS BEING MADE PURSUANT TO AN EXEMPTION FROM, OR
     IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE
     SECURITIES ACT; AND (4) AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM
     THIS IS TRANSFERRED A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. IN
     CONNECTION WITH ANY TRANSFER OF THIS NOTE PRIOR TO THE EXPIRATION OF THE
     HOLDING PERIOD APPLICABLE TO SALES OF THIS NOTE UNDER RULE 144(K) UNDER THE
     SECURITIES ACT (OR ANY SUCCESSOR PROVISION), THE HOLDER MUST CHECK THE
     APPROPRIATE BOX SET FORTH ON THE REVERSE HEREOF RELATING TO THE MANNER OF
     SUCH TRANSFER AND SUBMIT THIS CERTIFICATE TO STATE STREET BANK AND TRUST
     COMPANY OF CALIFORNIA, N.A., AS TRUSTEE (OR A SUCCESSOR TRUSTEE, AS
     APPLICABLE). IF THE PROPOSED TRANSFEREE IS AN INSTITUTIONAL ACCREDITED
     INVESTOR OR IS A PURCHASER WHO IS NOT A UNITED STATES PERSON, THE HOLDER
     MUST, PRIOR TO SUCH TRANSFER, FURNISH TO STATE STREET BANK AND TRUST
     COMPANY OF CALIFORNIA, N.A., AS TRUSTEE (OR A SUCCESSOR TRUSTEE, AS
     APPLICABLE), SUCH CERTIFICATIONS, LEGAL OPINIONS OR OTHER INFORMATION AS
     SUCH TRUSTEE MAY REASONABLY REQUIRE TO CONFIRM THAT SUCH TRANSFER IS BEING
     MADE PURSUANT TO AN EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE
     REGISTRATION REQUIREMENTS OF THE SECURITIES ACT. THIS LEGEND WILL BE
     REMOVED UPON THE EARLIER OF THE TRANSFER OF THIS NOTE PURSUANT TO CLAUSE
     (2)(F) ABOVE

                                      -15-

<PAGE>

     OR UPON ANY TRANSFER OF THIS NOTE UNDER RULE 144(K) UNDER THE SECURITIES
     ACT (OR ANY SUCCESSOR PROVISION). AS USED HEREIN, THE TERMS "UNITED STATES"
     AND "U.S. PERSON" HAVE THE MEANINGS GIVEN TO THEM BY REGULATION S UNDER THE
     SECURITIES ACT. THE INDENTURE CONTAINS A PROVISION REQUIRING THE TRUSTEE TO
     REFUSE TO REGISTER ANY TRANSFER OF THIS NOTE IN VIOLATION OF THE FOREGIONG
     RESTRICTION.

     Any Note (or security issued in exchange or substitution therefor) as to
which such restrictions on transfer shall have expired in accordance with their
terms or as to conditions for removal of the foregoing legend set forth therein
have been satisfied may, upon surrender of such Note for exchange to the Note
registrar in accordance with the provisions of this Section 2.5, be exchanged
for a new Note or Notes, of like tenor and aggregate principal amount, which
shall not bear the restrictive legend required by this Section 2.5(d).

     Notwithstanding any other provisions of this Indenture (other than the
provisions set forth in the second paragraph of Section 2.5(c) and in this
Section 2.5(d)), a Note in global form may not be transferred as a whole or in
part 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.

     The Depositary shall be a clearing agency registered under the Exchange
Act. The Company initially appoints The Depository Trust Company to act as
Depositary with respect to the Notes in global form. Initially, the Global Note
shall be issued to the Depositary, registered in the name of Cede & Co., as the
nominee of the Depositary, and deposited with the Custodian for Cede & Co.

     If at any time the Depositary for a Note in global form notifies the
Company that it is unwilling or unable to continue as Depositary for such Note,
the Company may appoint a successor Depositary with respect to such Note. If a
successor Depositary is not appointed by the Company within ninety (90) days
after the Company receives such notice, the Company will execute, and the
Trustee, upon receipt of an Officers' Certificate for the authentication and
delivery of Notes, will authenticate and deliver, Notes in certificated form, in
aggregate principal amount equal to the principal amount of such Note in global
form, in exchange for such Note in global form.

     If a Note in certificated form is issued in exchange for any portion of a
Note in global form after the close of business at the office or agency where
such exchange occurs on any record date and before the opening of business at
such office or agency on the next succeeding interest payment date, interest
will not be payable on such interest payment date in respect of such
certificated Note, but will be payable on such interest payment date, subject to
the provisions of Section 2.3, only to the Person to whom interest in respect of
such portion of such Note in global form is payable in accordance with the
provisions of this Indenture.

     Notes in certificated form issued in exchange for all or a part of a Note
in global form pursuant to this Section 2.5 shall be registered in such names
and in such authorized denominations

                                      -16-

<PAGE>

as the Depositary, pursuant to instructions from its direct or indirect
participants or otherwise, shall instruct the Trustee. Upon execution and
authentication, the Trustee shall deliver such Notes in certificated form to the
Persons in whose names such Notes in certificated form are so registered.

     At such time as all interests in a Note in global form have been redeemed,
converted, canceled, exchanged for Notes in certificated form, or transferred to
a transferee who receives Notes in certificated form thereof, such Note in
global form shall, upon receipt thereof, be canceled by the Trustee in
accordance with standing procedures and instructions existing between the
Depositary and the Custodian. At any time prior to such cancellation, if any
interest in a Note in global form is exchanged for Notes in certificated form,
redeemed, converted, repurchased or canceled, or transferred to a transferee who
receives Notes in certificated form therefor or any Note in certificated form is
exchanged or transferred for part of a Note in global form, the principal amount
of such Note in global form shall, in accordance with the standing procedures
and instructions existing between the Depositary and the Custodian, be
appropriately reduced or increased, as the case may be, and an endorsement shall
be made on such Note in global form, by the Trustee or the Custodian, at the
direction of the Trustee, to reflect such reduction or increase.

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

     THE COMMON STOCK EVIDENCED HEREBY HAS NOT BEEN REGISTERED UNDER THE UNITED
     STATES SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY
     STATE SECURITIES LAWS, AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD WITHIN
     THE UNITED STATES OR TO, OR FOR THE ACCOUNT OR BENEFIT OF, UNITED STATES
     PERSONS EXCEPT AS SET FORTH IN THE FOLLOWING SENTENCE. THE HOLDER HEREOF
     AGREES THAT, UNTIL THE EXPIRATION OF THE HOLDING PERIOD APPLICABLE TO SALES
     OF THE COMMON STOCK EVIDENCED HEREBY UNDER RULE 144(K) UNDER THE SECURITIES
     ACT (OR ANY SUCCESSOR PROVISION), (1) IT WILL NOT RESELL OR OTHERWISE
     TRANSFER THE COMMON STOCK EVIDENCED HEREBY EXCEPT (A) TO RIVERSTONE
     NETWORKS, INC. OR TO ANY SUBSIDIARY THEREOF, (B) INSIDE THE UNITED STATES
     TO A "QUALIFIED INSTITUTIONAL BUYER" (AS DEFINED IN RULE 144A UNDER THE
     SECURITIES ACT) IN COMPLIANCE WITH RULE 144A, (C) INSIDE THE UNITED STATES
     TO AN INSTITUTIONAL "ACCREDITED INVESTOR" (AS DEFINED IN RULE 501(A)(1),
     (2), (3) OR (7) UNDER THE SECURITIES ACT)

                                      -17-

<PAGE>

     THAT PRIOR TO SUCH TRANSFER, FURNISHES TO MELLON INVESTOR SERVICES, L.L.C.,
     AS TRANSFER AGENT (OR A SUCCESSOR TRANSFER AGENT, AS APPLICABLE), A SIGNED
     LETTER CONTAINING CERTAIN REPRESENTATIONS AND AGREEMENTS RELATING TO THE
     RESTRICTIONS ON TRANSFER OF THE COMMON STOCK EVIDENCED HEREBY (THE FORM OF
     WHICH LETTER CAN BE OBTAINED FROM SUCH TRANSFER AGENT OR A SUCCESSOR
     TRANSFER AGENT, AS APPLICABLE), (D) OUTSIDE THE UNITED STATES IN COMPLIANCE
     WITH RULE 904 UNDER THE SECURITIES ACT, (E) PURSUANT TO THE EXEMPTION FROM
     REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT (IF AVAILABLE),
     OR (F) PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED
     EFFECTIVE UNDER THE SECURITIES ACT (AND WHICH CONTINUES TO BE EFFECTIVE AT
     THE TIME OF SUCH TRANSFER); (2) PRIOR TO SUCH TRANSFER (OTHER THAN A
     TRANSFER PURSUANT TO CLAUSE (1)(F) ABOVE), IT WILL FURNISH TO MELLON
     INVESTOR SERVICES, L.L.C., AS TRANSFER AGENT (OR A SUCCESSOR TRANSFER
     AGENT, AS APPLICABLE), SUCH CERTIFICATIONS, LEGAL OPINIONS OR OTHER
     INFORMATION AS IT MAY REASONABLY REQUIRE TO CONFIRM THAT SUCH TRANSFER IS
     BEING MADE PURSUANT TO AN EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT
     TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT; AND (3) IT WILL
     DELIVER TO EACH PERSON TO WHOM THE COMMON STOCK EVIDENCED HEREBY IS
     TRANSFERRED (OTHER THAN A TRANSFER PURSUANT TO CLAUSE 1(F) ABOVE) A NOTICE
     SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. IF THE PROPOSED TRANSFEREE IS
     AN INSTITUTIONAL ACCREDITED INVESTOR OR IS A PURCHASER WHO IS NOT A U.S.
     PERSON, THE HOLDER MUST, PRIOR TO SUCH TRANSFER, FURNISH TO MELLON INVESTOR
     SERVICES, L.L.C. (OR A SUCCESSOR TRANSFER AGENT, AS APPLICABLE), SUCH
     CERTIFICATIONS, LEGAL OPINIONS OR OTHER INFORMATION AS IT MAY REASONABLY
     REQUIRE TO CONFIRM THAT SUCH TRANSFER IS BEING MADE PURSUANT TO AN
     EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION
     REQUIREMENTS OF THE SECURITIES ACT. THIS LEGEND WILL BE REMOVED UPON THE
     EARLIER OF THE TRANSFER OF THE COMMON STOCK EVIDENCED HEREBY PURSUANT TO
     CLAUSE (1)(F) ABOVE OR UPON ANY TRANSFER OF THE COMMON STOCK EVIDENCED
     HEREBY AFTER THE EXPIRATION OF THE HOLDING PERIOD APPLICABLE TO SALES OF
     THE SECURITY EVIDENCED HEREBY UNDER RULE 144(K) UNDER THE SECURITIES ACT
     (OR ANY SUCCESSOR PROVISION). AS USED HEREIN, THE TERMS "UNITED STATES" AND
     "U.S. PERSON" HAVE THE MEANINGS GIVEN TO THEM BY REGULATION S UNDER THE
     SECURITIES ACT.

                                      -18-


<PAGE>

     Any such Common Stock as to which such restrictions on transfer shall have
expired in accordance with their terms or as to which the conditions for removal
of the foregoing legend set forth therein have been satisfied may, upon
surrender of the certificates representing such shares of Common Stock for
exchange in accordance with the procedures of the transfer agent for the Common
Stock, be exchanged for a new certificate or certificates for a like number of
shares of Common Stock, which shall not bear the restrictive legend required by
this Section 2.5(e).

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

     Section 2.6 Mutilated, Destroyed, Lost or Stolen Notes. In case any Note
                 ------------------------------------------
shall become mutilated or be destroyed, lost or stolen, the Company in its
discretion may execute, and upon its written request the Trustee or an
authenticating agent appointed by the Trustee shall authenticate and make
available for delivery, a new Note, bearing a number not contemporaneously
outstanding, in exchange and substitution for the mutilated Note, or in lieu of
and in substitution for the Note so destroyed, lost or stolen. In every case the
applicant for a substituted Note shall furnish to the Company, to the Trustee
and, if applicable, to such authenticating agent such security or indemnity as
may be required by them to save each of them harmless for any loss, liability,
cost or expense caused by or connected with such substitution, and, in every
case of destruction, loss or theft, the applicant shall also furnish to the
Company, to the Trustee and, if applicable, to such authenticating agent
evidence to their satisfaction of the destruction, loss or theft of such Note
and of the ownership thereof.

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

                                      -19-

<PAGE>

applicable, any paying agent or conversion agent evidence to their satisfaction
of the destruction, loss or theft of such Note and of the ownership thereof.

     Every substitute Note issued pursuant to the provisions of this Section 2.6
by virtue of the fact that any Note is destroyed, lost or stolen shall
constitute an additional contractual obligation of the Company, whether or not
the destroyed, lost or stolen Note shall be found at any time, and shall be
entitled to all the benefits of (but shall be subject to all the limitations set
forth in) this Indenture equally and proportionately with any and all other
Notes duly issued hereunder. To the extent permitted by law, all Notes shall be
held and owned upon the express condition that the foregoing provisions are
exclusive with respect to the replacement or payment or conversion of mutilated,
destroyed, lost or stolen Notes and shall preclude any and all other rights or
remedies notwithstanding any law or statute existing or hereafter enacted to the
contrary with respect to the replacement or payment or conversion of negotiable
instruments or other securities without their surrender.

     Section 2.7 Temporary Notes. Pending the preparation of Notes in
                 ---------------
certificated form, the Company may execute and the Trustee or an authenticating
agent appointed by the Trustee shall, upon the written request of the Company,
authenticate and deliver temporary Notes (printed or lithographed). Temporary
Notes shall be issuable in any authorized denomination, and substantially in the
form of the Notes in certificated form, but with such omissions, insertions and
variations as may be appropriate for temporary Notes, all as may be determined
by the Company. Every such temporary Note shall be executed by the Company and
authenticated by the Trustee or such authenticating agent upon the same
conditions and in substantially the same manner, and with the same effect, as
the Notes in certificated form. Without unreasonable delay the Company will
execute and deliver to the Trustee or such authenticating agent Notes in
certificated form (other than in the case of Notes in global form) and thereupon
any or all temporary Notes (other than any such Note in global form) may be
surrendered in exchange therefor, at each office or agency maintained by the
Company pursuant to Section 5.2 and the Trustee or such authenticating agent
shall authenticate and make available for delivery in exchange for such
temporary Notes an equal aggregate principal amount of Notes in certificated
form. Such exchange shall be made by the Company at its own expense and without
any charge therefor. Until so exchanged, the temporary Notes shall in all
respects be entitled to the same benefits and subject to the same limitations
under this Indenture as Notes in certificated form authenticated and delivered
hereunder.

     Section 2.8 Cancellation of Notes Paid, Etc. All Notes surrendered for the
                 -------------------------------
purpose of payment, redemption, conversion, exchange or registration of transfer
shall, if surrendered to the Company or any paying agent or any Note registrar
or any conversion agent, be surrendered to the Trustee and promptly canceled by
it, or, if surrendered to the Trustee, shall be promptly canceled by it, and no
Notes shall be issued in lieu thereof except as expressly permitted by any of
the provisions of this Indenture. The Trustee shall dispose of such canceled
Notes in accordance with its customary procedures. If the Company shall acquire
any of the Notes, such acquisition shall not operate as a redemption or
satisfaction of the indebtedness represented by such Notes unless and until the
same are delivered to the Trustee for cancellation.

                                      -20-


<PAGE>

     Section 2.9 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 as a convenience to Noteholders; provided,
however, 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 and that reliance may be placed only on the other
identification numbers printed on the Notes, and any such redemption shall not
be affected by any defect in or omission of such numbers. The Company will
promptly notify the Trustee of any change in the "CUSIP" numbers.



                                 ARTICLE THREE

                               REDEMPTION OF NOTES

     Section 3.1 Redemption by the Company.
                 -------------------------

          (a) Provisional Redemption by the Company. The Notes may be redeemed
              -------------------------------------
at the election of the Company, in a whole or in part from time to time, at any
time prior to December 3, 2004 (a "Provisional Redemption"), upon notice as set
forth in Section 3.2, at a redemption price equal to $1,000 per $1,000 aggregate
principal amount of the Notes redeemed if: (1) the Closing Price of the Common
Stock has exceeded 150% of the Conversion Price, as such may be adjusted from
time to time, then in effect for at least 20 Trading Days within a period of 30
consecutive Trading Days ending on the Trading Day prior to the date of mailing
of the provisional notice of redemption pursuant to Section 3.2 (the "Notice
Date"), and (2) if the redemption occurs prior to November 21, 2003, a
registration statement covering resales of the Notes and the Common Stock
issuable upon conversion thereof is effective and available for use and is
expected to remain effective for the 30 days following the Provisional
Redemption Date unless registration is no longer required. The Conversion Price
shall equal (i) $1,000 divided by (ii) the Conversion Rate for $1,000 principal
amount of the Notes.

     Upon any such Provisional Redemption, the Company shall make an additional
payment in cash (the "Make-Whole Payment") with respect to the Notes called for
redemption to holders on the Notice Date equal to the aggregate amount of the
interest otherwise payable on the Notes from the last day through which interest
was paid on the Notes, or November 21, 2001 if no interest has been paid,
through December 3, 2004. The Company shall make the Make-Whole Payment on all
Notes called for Provisional Redemption, including those Notes converted between
the Notice Date and the Provisional Redemption Date.

          (b) Non-Provisional Redemption by the Company. At any time on or after
              -----------------------------------------
December 3, 2004, and prior to maturity, the Notes may be redeemed at the option
of the Company (a "Non-Provisional Redemption"), in whole or in part, upon
notice as set forth in Section 3.2 (the "Notice Date"), at the following
Non-Provisional Redemption prices (expressed as percentages of the principal
amount), together in each case with accrued and unpaid interest, if any
(including Liquidated Damages, if any) to, but excluding, the date fixed for
redemption:

<PAGE>

                                      -21-



Period                                                         Redemption Price
------                                                         ----------------

Beginning on December 3, 2004 and ending on
 November 30, 2005                                                  101.50%

Beginning on December 1, 2005 and ending on
 November 30, 2006                                                  100.75%

and 100% on December 1, 2006; provided, however, that if the date fixed for
redemption is on a June 1 or December 1, then the interest payable on such date
shall be paid to the holder of record on the preceding May 15 or November 15,
respectively.

     Section 3.2 Notice of Redemptions; Selection of Notes. In case the Company
                 -----------------------------------------
shall desire to exercise the right to redeem all or, as the case may be, any
part of the Notes pursuant to Section 3.1, it shall fix a date for redemption
and it or, at its written request received by the Trustee not fewer than
forty-five (45) days prior (or such shorter period of time as may be acceptable
to the Trustee) to the date fixed for redemption, the Trustee in the name of and
at the expense of the Company, shall mail or cause to be mailed a notice of such
redemption not fewer than thirty (30) nor more than sixty (60) days prior to the
date fixed for redemption to the holders of Notes so to be redeemed as a whole
or in part at their last addresses as the same appear on the Note register;
provided, however, that if the Company shall give such notice, it shall also
give written notice, and written notice of the Notes to be redeemed, to the
Trustee. The Company may not give notice of any redemption of the Notes if a
default in payment of interest or premium, if any, on the Notes has occurred and
is continuing. Such mailing shall be by first class mail. The notice if mailed
in the manner herein provided shall be conclusively presumed to have been duly
given, whether or not the holder receives such notice. In any case, failure to
give such notice by mail or any defect in the notice to the holder of any Note
designated for redemption as a whole or in part shall not affect the validity of
the proceedings for the redemption of any other Note. Concurrently with the
mailing of any such notice of redemption, the Company shall issue a press
release announcing such redemption, the form and content of which press release
shall be determined by the Company in its sole discretion. The failure to issue
any such press release or any defect therein shall not affect the validity of
the redemption notice or any of the proceedings for the redemption of any Note
called for redemption.

     Each such notice of redemption shall specify the aggregate principal amount
of Notes to be redeemed, the CUSIP number or numbers of the Notes being
redeemed, the date fixed for redemption (which shall be a Business Day), the
redemption price at which Notes are to be redeemed, the place or places of
payment, that payment will be made upon presentation and surrender of such
Notes, that interest accrued to the date fixed for redemption will be paid as
specified in said notice, and that on and after said date interest thereon or on
the portion thereof to be redeemed will cease to accrue. Such notice shall also
state the current Conversion Rate and the date on which the right to convert
such Notes or portions thereof into Common Stock will expire. If the Company
elects to make a cash payment in lieu of issuing shares of Common Stock upon any
conversion of any Notes called for redemption, the notice of redemption must
also specify such election. If the notice of redemption fails to specify that
the Company intends to make a cash payment in lieu of issuing shares of Commons
Stock upon conversion of the Notes, upon conversion, the Notes will be
convertible only into shares of its Common Stock. If fewer than all the Notes
are to be redeemed, the notice of redemption shall identify the Notes to be
redeemed

                                      -22-

<PAGE>

(including CUSIP numbers, if any). In case any Note is to be redeemed in part
only, the notice of redemption shall state the portion of the principal amount
thereof to be redeemed and shall state that, on and after the date fixed for
redemption, upon surrender of such Note, a new Note or Notes in principal amount
equal to the unredeemed portion thereof will be issued.

     On or prior to the redemption date specified in the notice of redemption
given as provided in this Section 3.2, the Company will deposit with the Trustee
or with one or more paying agents (or, if the Company is acting as its own
paying agent, set aside, segregate and hold in trust as provided in Section 5.4)
an amount of money in immediately available funds sufficient to redeem on the
redemption date all the Notes (or portions thereof) so called for redemption
(other than those theretofore surrendered for conversion into Common Stock) at
the appropriate redemption price, together with accrued interest to, but
excluding, the date fixed for redemption; provided, however, that if such
payment is made on the redemption date it must be received by the Trustee or
paying agent, as the case may be, by 10:00 a.m. New York City time on such date.
The Company shall be entitled to retain any interest, yield or gain on amounts
deposited with the Trustee or any paying agent pursuant to this Section 3.2 in
excess of amounts required hereunder to pay the redemption price together with
accrued interest to, but excluding, the date fixed for redemption. If any Note
called for redemption is converted into shares of Common Stock pursuant hereto
prior to such redemption, any money deposited with the Trustee or any paying
agent or so segregated and held in trust for the redemption of such Note shall
be paid to the Company upon its written request, or, if then held by the
Company, shall be discharged from such trust. Whenever any Notes are to be
redeemed, the Company will give the Trustee written notice in the form of an
Officers' Certificate not fewer than forty five (45) days (or such shorter
period of time as may be acceptable to the Trustee) prior to the redemption date
as to the aggregate principal amount of Notes to be redeemed.

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

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

                                      -23-


<PAGE>

     Section 3.3 Payment of Notes Called for Redemption. If notice of redemption
                 --------------------------------------
has been given as above provided, the Notes or portion of Notes with respect to
which such notice has been given shall, unless converted into cash or Common
Stock pursuant to the terms hereof, become due and payable on the date fixed for
redemption and at the place or places stated in such notice at the applicable
redemption price, together with interest accrued to (but excluding) the date
fixed for redemption, and on and after said date (unless the Company shall
default in the payment of such Notes at the redemption price, together with
interest accrued to said date) interest on the Notes or portion of Notes so
called for redemption shall cease to accrue and, after the close of business on
the Business Day next preceding the date fixed for redemption, such Notes shall
cease to be convertible and, except as provided in Sections 8.5 and 13.4, to be
entitled to any benefit or security under this Indenture, and the holders
thereof shall have no right in respect of such Notes except the right to receive
the redemption price thereof and unpaid interest to (but excluding) the date
fixed for redemption. On presentation and surrender of such Notes at a place of
payment in said notice specified, the said Notes or the specified portions
thereof shall be paid and redeemed by the Company at the applicable redemption
price, together with interest accrued thereon to (but excluding) the date fixed
for redemption; provided, however, that if the applicable redemption date is an
interest payment date, the semi-annual payment of interest becoming due on such
date shall be payable to the holders of such Notes registered as such on the
relevant record date instead of the holders surrendering such Notes for
redemption on such date.

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

     Notwithstanding the foregoing, the Trustee shall not redeem any Notes or
mail any notice of redemption during the continuance of a default in payment of
interest or premium, if any, on the Notes. If any Note called for redemption
shall not be so paid upon surrender thereof for redemption, the principal and
premium, if any, shall, until paid or duly provided for, bear interest from the
date fixed for redemption at the rate borne by the Note and such Note shall
remain convertible into Common Stock until the principal and premium, if any,
and interest shall have been paid or duly provided for.

     Section 3.4 Conversion Arrangement on Call for Redemption. In connection
                 ---------------------------------------------
with any redemption of Notes, the Company may arrange for the purchase and
conversion of any Notes by an agreement with one or more investment bankers or
other purchasers to purchase such Notes by paying to the Trustee in trust for
the Noteholders, on or before the date fixed for redemption, an amount not less
than the applicable redemption price, together with interest accrued to (but
excluding) the date fixed for redemption, of such Notes. Notwithstanding
anything to the contrary contained in this Article Three, the obligation of the
Company to pay the redemption price of such Notes, together with interest
accrued to (but excluding) the date fixed for redemption, shall be deemed to be
satisfied and discharged to the extent such amount is so paid by such
purchasers. If such an agreement is entered into, a copy of which will be filed
with the Trustee prior to the date fixed for redemption, any Notes not duly
surrendered for conversion by the holders thereof may, at

                                      -24-

<PAGE>

the option of the Company, be deemed, to the fullest extent permitted by law,
acquired by such purchasers from such holders and (notwithstanding anything to
the contrary contained in Article Fifteen) surrendered by such purchasers for
conversion, all as of immediately prior to the close of business on the date
fixed for redemption (and the right to convert any such Notes shall be extended
through such time), subject to payment of the above amount as aforesaid. At the
direction of the Company, the Trustee shall hold and dispose of any such amount
paid to it in the same manner as it would monies deposited with it by the
Company for the redemption of Notes. Without the Trustee's prior written
consent, no arrangement between the Company and such purchasers for the purchase
and conversion of any Notes shall increase or otherwise affect any of the
powers, duties, responsibilities or obligations of the Trustee as set forth in
this Indenture.

     Section 3.5 Redemption at Option of Holders.
                 -------------------------------

          (a) If there shall occur a Fundamental Change at any time prior to
maturity of the Notes, then each Noteholder shall have the right, at such
holder's option, to require the Company to redeem all of such holder's Notes, or
any portion thereof that is an integral multiple of $1,000 principal amount, on
the date (the "Repurchase Date") that is thirty (30) days after the date of the
Company Notice (as defined in Section 3.5(b) below) of such Fundamental Change
(or, if such 30th day is not a Business Day, the immediately preceding Business
Day) at a redemption price equal to 100% of the principal amount thereof,
together with accrued interest to (but excluding) the Repurchase Date; provided,
however, that, if such Repurchase Date is a June 1 or December 1, then the
interest payable on such date shall be paid to the holders of record of the
Notes on the next preceding May 15 or November 15, respectively.

     Upon presentation of any Note redeemed in part only, the Company shall
execute and, upon the Company's written direction to the Trustee, the Trustee
shall authenticate and deliver to the holder thereof, at the expense of the
Company, a new Note or Notes, of authorized denominations, in principal amount
equal to the unredeemed portion of the Notes so presented.

          (b) On or before the tenth day after the occurrence of a Fundamental
Change, the Company or at its written request (which must be received by the
Trustee at least five (5) Business Days prior to the date the Trustee is
requested to give notice as described below, unless the Trustee shall agree in
writing to a shorter period), the Trustee in the name of and at the expense of
the Company, shall mail or cause to be mailed to all holders of record on the
date of the Fundamental Change a notice (the "Company Notice") of the occurrence
of such Fundamental Change and of the redemption right at the option of the
holders arising as a result thereof. Such notice shall be mailed in the manner
and with the effect set forth in the first paragraph of Section 3.2 (without
regard for the time limits set forth therein). If the Company shall give such
notice, the Company shall also deliver a copy of the Company Notice to the
Trustee at such time as it is mailed to Noteholders. Concurrently with the
mailing of any Company Notice, the Company shall issue a press release
announcing such Fundamental Change referred to in the Company Notice, the form
and content of which press release shall be determined by the Company in its
sole discretion. The failure to issue any such press release or any defect
therein shall not affect the validity of the Company Notice or

                                      -25-

<PAGE>

any proceedings for the redemption of any Note which any Noteholder may elect to
have the Company repurchase as provided in this Section 3.5.

     Each Company Notice shall specify the circumstances constituting the
Fundamental Change, the Repurchase Date, the price at which the Company shall be
obligated to redeem Notes, that the holder must exercise the redemption right on
or prior to the close of business on the Repurchase Date (the "Fundamental
Change Expiration Time"), that the holder shall have the right to withdraw any
Notes surrendered prior to the Fundamental Change Expiration Time, a description
of the procedure which a Noteholder must follow to exercise such redemption
right and to withdraw any surrendered Notes, the place or places where the
holder is to surrender such holder's Notes, and the amount of interest accrued
on each Note to the Repurchase Date.

     No failure of the Company to give the foregoing notices and no defect
therein shall limit the Noteholders' redemption rights or affect the validity of
the proceedings for the repurchase of the Notes pursuant to this Section 3.5.

          (c) For a Note to be so redeemed at the option of the holder, the
Company must receive at the office or agency of the Company maintained for that
purpose or, at the option of such holder, the Corporate Trust Office, such Note
with the form entitled "Option to Elect Repayment Upon A Fundamental Change" on
the reverse thereof duly completed, together with such Notes duly endorsed for
transfer, on or before the Fundamental Change Expiration Time. All questions as
to the validity, eligibility (including time of receipt) and acceptance of any
Note for repayment shall be determined by the Company, whose determination shall
be final and binding absent manifest error.

          (d) On or prior to the Repurchase Date, the Company will deposit with
the Trustee or with one or more paying agents (or, if the Company is acting as
its own paying agent, set aside, segregate and hold in trust as provided in
Section 5.4) an amount of money sufficient to repay on the Repurchase Date all
the Notes to be redeemed on such date at the appropriate redemption price,
together with accrued interest to (but excluding) the Repurchase Date; provided,
however, that if such payment is made on the Repurchase Date it must be received
by the Trustee or paying agent, as the case may be, by 10:00 a.m. New York City
time, on such date. Payment for Notes surrendered for redemption (and not
withdrawn) prior to the Fundamental Change Expiration Time will be made promptly
(but in no event more than five (5) Business Days) following the Repurchase Date
by mailing checks for the amount payable to the holders of such Notes entitled
thereto as they shall appear on the registry books of the Company.

          (e) In the case of a reclassification, change, consolidation, merger,
combination, sale or conveyance to which Section 15.6 applies, in which the
Common Stock of the Company is changed or exchanged as a result into the right
to receive stock, securities or other property or assets (including cash), which
includes shares of Common Stock of the Company or shares of common stock of
another Person that are, or upon issuance will be, traded on a United States
national securities exchange or approved for trading on an established automated
over-the-counter trading market in the United States and such shares constitute
at the time such change or exchange becomes effective in excess of 50% of the
aggregate fair market value of such stock, securities or other property or
assets (including cash) (as determined by the Company, which determination shall
be

                                      -26-

<PAGE>

conclusive and binding), then the Person formed by such consolidation or
resulting from such merger or which acquires such assets, as the case may be,
shall execute and deliver to the Trustee a supplemental indenture (accompanied
by an Opinion of Counsel that such supplemental indenture complies with the
Trust Indenture Act as in force at the date of execution of such supplemental
indenture) modifying the provisions of this Indenture relating to the right of
holders of the Notes to cause the Company to repurchase the Notes following a
Fundamental Change, including without limitation the applicable provisions of
this Section 3.5 and the definitions of Common Stock and Fundamental Change, as
appropriate, as determined in good faith by the Company (which determination
shall be conclusive and binding), to make such provisions apply to such other
Person if different from the Company and the common stock issued by such Person
(in lieu of the Company and the Common Stock of the Company).

          (f) The Company will comply with the provisions of Rule 13e-4 and any
other tender offer rules under the Exchange Act to the extent then applicable in
connection with the redemption rights of the holders of Notes in the event of a
Fundamental Change.



                                  ARTICLE FOUR

                             SUBORDINATION OF NOTES

     Section 4.1 Agreement of Subordination. The Company covenants and agrees,
                 --------------------------
and each holder of Notes issued hereunder by its acceptance thereof likewise
covenants and agrees, that all Notes shall be issued subject to the provisions
of this Article Four, and each Person holding any Note, whether upon original
issue or upon registration of transfer, assignment or exchange thereof, accepts
and agrees to be bound by such provisions.

     The payment of the principal of, premium, if any, and interest (including
Liquidated Damages, if any) on all Notes (including, but not limited to, the
redemption price with respect to the Notes called for redemption in accordance
with Section 3.2 or submitted for redemption in accordance with Section 3.5, as
the case may be, as provided in this Indenture) issued hereunder shall, to the
extent and in the manner hereinafter set forth, be subordinated and subject in
right of payment to the prior payment in full in cash or other payment
satisfactory to the holders of Senior Indebtedness of all Senior Indebtedness,
whether outstanding at the date of this Indenture or thereafter incurred.

     No provision of this Article Four shall prevent the occurrence of any
default or Event of Default hereunder.

     Section 4.2 Payments to Noteholders. No payment shall be made with respect
                 -----------------------
to the principal of, premium, if any, or interest (including Liquidated Damages,
if any) on the Notes (including, but not limited to, the redemption price with
respect to the Notes to be called for redemption in accordance with Section 3.2
or submitted for redemption in accordance with Section 3.5, as the case may be,
as provided in this Indenture), except payments and distributions made by the
Trustee as permitted by the first or second paragraph of Section 4.5, if:

                                      -27-


<PAGE>

               (i) a default in the payment of principal, premium, if any,
     interest, rent or other obligations in respect of Senior Indebtedness
     occurs and is continuing beyond any applicable period of grace (a "Payment
     Default"); or

               (ii) a default, other than a Payment Default, on any Designated
     Senior Indebtedness occurs and is continuing that then permits holders of
     such Designated Senior Indebtedness to accelerate its maturity and the
     Trustee receives a notice of the default (a "Payment Blockage Notice") from
     a holder of Designated Senior Indebtedness, a Representative of Designated
     Senior Indebtedness or the Company (a "Non-Payment Default").

     If the Trustee receives any Payment Blockage Notice pursuant to clause (ii)
above, no subsequent Payment Blockage Notice shall be effective for purposes of
this Section 4.2 unless and until (A) at least 365 days shall have elapsed since
the initial effectiveness of the immediately prior Payment Blockage Notice and
(B) all scheduled payments of principal, premium, if any, and interest
(including Liquidated Damages, if any) on the Notes that have come due have been
paid in full in cash. No Non-Payment 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. The Company may and
shall resume payments on and distributions in respect of the Notes upon:

               (1) in the case of a Payment Default, the date upon which any
     such Payment Default is cured or waived or ceases to exist,

               (2) in the case of a Non-Payment Default, the earlier of (a) the
     date upon which such default is cured or waived or ceases to exist or (b)
     179 days after the applicable Payment Blockage Notice is received by the
     Trustee, or

               (3) if the maturity of the Designated Senior Indebtedness has not
     been accelerated, or in the case of any lease, 179 days after notice is
     received by the Company that the lessor under such lease has exercised its
     right to terminate the lease or required the Company to make an irrevocable
     offer to terminate the lease following an event of default under the lease.

unless this Article Four otherwise prohibits the payment or distribution at the
time of such payment or distribution.

     Upon any payment by the Company, or distribution of assets of the Company
of any kind or character, whether in cash, property or securities, to creditors
upon any dissolution or winding up or liquidation or reorganization of the
Company, whether voluntary or involuntary or in bankruptcy, insolvency,
receivership or other proceedings, all amounts due or to become due upon all
Senior Indebtedness shall first be paid in full in cash or other payment
satisfactory to the holders of such Senior Indebtedness, or payment thereof in
accordance with its terms provided for in cash or other

                                      -28-

<PAGE>

payment satisfactory to the holders of such Senior Indebtedness before any
payment is made on account of the principal of, premium, if any, or interest
(including Liquidated Damages, if any) on the Notes (except payments made
pursuant to Article Thirteen from monies deposited with the Trustee pursuant
thereto prior to commencement of proceedings for such dissolution, winding up,
liquidation or reorganization), and upon any such dissolution or winding up or
liquidation or reorganization of the Company or bankruptcy, insolvency,
receivership or other proceeding, any payment by the Company, or distribution of
assets of the Company of any kind or character, whether in cash, property or
securities, to which the holders of the Notes or the Trustee would be entitled,
except for the provisions of this Article Four, shall (except as aforesaid) be
paid by the Company or by any receiver, trustee in bankruptcy, liquidating
trustee, agent or other Person making such payment or distribution, or by the
holders of the Notes or by the Trustee under this Indenture if received by them
or it, directly to the holders of Senior Indebtedness (pro rata to such holders
on the basis of the respective amounts of Senior Indebtedness held by such
holders, or as otherwise required by law or a court order) or their
Representative or Representatives, or to the trustee or trustees under any
indenture pursuant to which any instruments evidencing any Senior Indebtedness
may have been issued, as their respective interests may appear, to the extent
necessary to pay all Senior Indebtedness in full in cash or other payment
satisfactory to the holders of such Senior Indebtedness, after giving effect to
any concurrent payment or distribution to or for the holders of Senior
Indebtedness, before any payment or distribution is made to the holders of the
Notes or to the Trustee.

     For purposes of this Article Four, the words, "cash, property or
securities" shall not be deemed to include shares of stock of the Company as
reorganized or readjusted, or securities of the Company or any other corporation
provided for by a plan of reorganization or readjustment, the payment of which
is subordinated at least to the extent provided in this Article Four with
respect to the Notes to the payment of all Senior Indebtedness which may at the
time be outstanding. The consolidation of the Company with, or the merger of the
Company into, another Person or the liquidation or dissolution of the Company
following the conveyance or transfer of its property as an entirety, or
substantially as an entirety, to another Person upon the terms and conditions
provided for in Article Twelve shall not be deemed a dissolution, winding-up,
liquidation or reorganization for the purposes of this Section 4.2 if such other
Person shall, as a part of such consolidation, merger, conveyance or transfer,
comply with the conditions stated in Article Twelve.

     In the event of the acceleration of the Notes because of an Event of
Default, no payment or distribution shall be made to the Trustee or any holder
of Notes in respect of the principal of, premium, if any, or interest (including
Liquidated Damages, if any) on the Notes (including, but not limited to, the
redemption price with respect to the Notes called for redemption in accordance
with Section 3.2 or submitted for redemption at the option of the holder in
accordance with Section 3.5, as the case may be, as provided in this Indenture),
except payments and distributions made by the Trustee as permitted by the first
or second paragraph of Section 4.5, until all Senior Indebtedness has been paid
in full in cash or other payment satisfactory to the holders of Senior
Indebtedness or such acceleration is rescinded in accordance with the terms of
this Indenture. If payment of the Notes is accelerated because of an Event of
Default, the Company or the Trustee shall promptly notify holders of Senior
Indebtedness of the acceleration.

                                      -29-


<PAGE>

     In the event that, notwithstanding the foregoing provisions, any payment or
distribution of assets of the Company of any kind or character, whether in cash,
property or securities (including, without limitation, by way of setoff or
otherwise), prohibited by the foregoing provisions in this Section 4.2, shall be
received by the Trustee or the holders of the Notes before all Senior
Indebtedness is paid in full in cash or other payment satisfactory to the
holders of such Senior Indebtedness, or provision is made for such payment
thereof in accordance with its terms in cash or other payment satisfactory to
the holders of such Senior Indebtedness, such payment or distribution shall be
held in trust for the benefit of and shall be paid over or delivered to the
holders of Senior Indebtedness or their Representative or Representatives, or to
the trustee or trustees under any indenture pursuant to which any instruments
evidencing any Senior Indebtedness may have been issued, as their respective
interests may appear, as calculated by the Company, for application to the
payment of any Senior Indebtedness remaining unpaid to the extent necessary to
pay all Senior Indebtedness in full in cash or other payment satisfactory to the
holders of such Senior Indebtedness, after giving effect to any concurrent
payment or distribution to or for the holders of such Senior Indebtedness.

     Nothing in this Section 4.2 shall apply to claims of, or payments to, the
Trustee under or pursuant to Section 8.6. This Section 4.2 shall be subject to
the further provisions of Section 4.5.

     Section 4.3 Subrogation of Notes. Subject to the payment in full of all
                 --------------------
Senior Indebtedness, the rights of the holders of the Notes shall be subrogated
to the extent of the payments or distributions made to the holders of such
Senior Indebtedness pursuant to the provisions of this Article Four (equally and
ratably with the holders of all indebtedness of the Company that by its express
terms, is subordinated to other indebtedness of the Company to substantially the
same extent as the Notes are subordinated and is entitled to like rights of
subrogation) to the rights of the holders of Senior Indebtedness to receive
payments or distributions of cash, property or securities of the Company
applicable to the Senior Indebtedness until the principal, premium, if any, and
interest (including Liquidated Damages, if any) on the Notes shall be paid in
full, and, for the purposes of such subrogation, no payments or distributions to
the holders of the Senior Indebtedness of any cash, property or securities to
which the holders of the Notes or the Trustee would be entitled except for the
provisions of this Article Four, and no payment over pursuant to the provisions
of this Article Four, to or for the benefit of the holders of Senior
Indebtedness by holders of the Notes or the Trustee, shall, as among the
Company, its creditors other than holders of Senior Indebtedness, and the
holders of the Notes, be deemed to be a payment by the Company to or on account
of the Senior Indebtedness, and no payments or distributions of cash, property
or securities to or for the benefit of the holders of the Notes pursuant to the
subrogation provisions of this Article Four, which would otherwise have been
paid to the holders of Senior Indebtedness, shall be deemed to be a payment by
the Company to or for the account of the Notes. It is understood that the
provisions of this Article Four are and are intended solely for the purposes of
defining the relative rights of the holders of the Notes, on the one hand, and
the holders of the Senior Indebtedness, on the other hand.

     Nothing contained in this Article Four or elsewhere in this Indenture or in
the Notes is intended to or shall impair, as among the Company, its creditors
other than the holders of Senior Indebtedness, and the holders of the Notes, the
obligation of the Company, which is absolute and


                                      -30-

<PAGE>

unconditional, to pay to the holders of the Notes the principal of, premium, if
any, and interest (including Liquidated Damages, if any) on the Notes as and
when the same shall become due and payable in accordance with their terms, or is
intended to or shall affect the relative rights of the holders of the Notes and
creditors of the Company other than the holders of the Senior Indebtedness, nor
shall anything herein or therein prevent the Trustee or the holder of any Note
from exercising all remedies otherwise permitted by applicable law upon default
under this Indenture, subject to the rights, if any, under this Article Four of
the holders of Senior Indebtedness in respect of cash, property or securities of
the Company received upon the exercise of any such remedy.

     Upon any payment or distribution of assets of the Company referred to in
this Article Four, the Trustee, subject to the provisions of Section 8.1, and
the holders of the Notes shall be entitled to rely upon any order or decree made
by any court of competent jurisdiction in which such bankruptcy, dissolution,
winding up, liquidation or reorganization proceedings are pending, or a
certificate of the receiver, trustee in bankruptcy, liquidating trustee, agent
or other Person making such payment or distribution, delivered to the Trustee or
to the holders of the 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 and all other facts pertinent thereto or to this Article Four.

     Section 4.4 Authorization to Effect Subordination. Each holder of a Note,
                 -------------------------------------
by its acceptance thereof, authorizes and directs the Trustee on the holder's
behalf to take such action as may be necessary or appropriate to effectuate the
subordination as provided in this Article Four and appoints the Trustee to act
as the 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 the third paragraph of Section 7.2 hereof at least
thirty (30) days before the expiration of the time to file such claim, the
holders of any Senior Indebtedness or their representatives are hereby
authorized to file an appropriate claim for and on behalf of the holders of the
Notes.

     Section 4.5 Notice to Trustee. The Company shall give prompt written notice
                 -----------------
in the form of an Officers' Certificate to a Responsible Officer of the Trustee
and to any paying agent of any fact known to the Company that would prohibit the
making of any payment of monies to or by the Trustee or any paying agent in
respect of the Notes pursuant to the provisions of this Article Four.
Notwithstanding the provisions of this Article Four 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 of monies to or by
the Trustee in respect of the Notes pursuant to the provisions of this Article
Four, unless and until a Responsible Officer of the Trustee shall have received
written notice thereof at the Corporate Trust Office from the Company (in the
form of an Officers' Certificate) or a Representative or a holder or holders of
Senior Indebtedness or from any trustee thereof, and before the receipt of any
such written notice, the Trustee, subject to the provisions of Section 8.1,
shall be entitled in all respects to assume that no such facts exist; provided,
however, that if on a date not less than two Business Days prior to the date
upon which by the terms hereof any such monies may become payable for any
purpose (including, without limitation, the payment of the principal of, or
premium, if any, or interest (including Liquidated Damages, if any) on any Note)
the Trustee shall not have received, with respect to such monies, the notice
provided

                                      -31-

<PAGE>

for in this Section 4.5, then, anything herein contained to the contrary
notwithstanding, the Trustee shall have full power and authority to apply monies
received to the purpose for which they were received, and shall not be affected
by any notice to the contrary that may be received by it on or after such prior
date.

     Notwithstanding anything in this Article Four to the contrary, nothing
shall prevent any payment by the Trustee to the Noteholders of monies deposited
with it pursuant to Section 13.1, and any such payment shall not be subject to
the provisions of Section 4.1 or 4.2.

     The Trustee, subject to the provisions of Section 8.1, shall be entitled to
rely on the delivery to it of a written notice by a Representative or a person
representing himself to be a holder of Senior Indebtedness (or a trustee on
behalf of such holder) to establish that such notice has been given by a
Representative or a holder of Senior Indebtedness or a trustee on behalf of any
such holder or holders. The Trustee shall not be required to make any payment or
distribution to or on behalf of a holder of Senior Indebtedness pursuant to this
Article Four unless it has received satisfactory evidence as to the amount of
Senior Indebtedness held by such Person, the extent to which such Person is
entitled to participate in such payment or distribution and any other facts
pertinent to the rights of such Person under this Article Four.

     Section 4.6 Trustee's Relation to Senior Indebtedness. The Trustee, in its
                 -----------------------------------------
individual capacity, shall be entitled to all the rights set forth in this
Article Four in respect of any Senior Indebtedness at any time held by it, to
the same extent as any other holder of Senior Indebtedness, and nothing in
Section 8.13 or elsewhere in this Indenture shall deprive the Trustee of any of
its rights as such holder.

     With respect to the holders of Senior Indebtedness, the Trustee undertakes
to perform or to observe only such of its covenants and obligations as are
specifically set forth in this Article Four, 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, subject to the
provisions of Section 8.1, the Trustee shall not be liable to any holder of
Senior Indebtedness (i) for any failure to make any payments or distributions to
such holder or (ii) if it shall pay over or deliver to holders of Notes, the
Company or any other Person money or assets to which any holder of Senior
Indebtedness shall be entitled by virtue of this Article Four or otherwise.

     Section 4.7 No Impairment of Subordination. No right of any present or
                 ------------------------------
future holder of any Senior Indebtedness to enforce subordination as herein
provided shall at any time in any way be prejudiced or impaired by any act or
failure to act on the part of the Company or by any act or failure to act, in
good faith, by any such holder, or by any noncompliance by the Company with the
terms, provisions and covenants of this Indenture, regardless of any knowledge
thereof which any such holder may have or otherwise be charged with.

     Section 4.8 Certain Conversions Not Deemed Payment. For the purposes of
                 --------------------------------------
this Article Four only, (1) the issuance and delivery of junior securities upon
conversion of Notes in accordance with Article Fifteen shall not be deemed to
constitute a payment or distribution on account of the

                                      -32-

<PAGE>

principal of, premium, if any, or interest (including Liquidated Damages, if
any) on 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 15.3), property or securities (other than
junior securities) upon conversion of a Note shall be deemed to constitute
payment on account of the principal of, premium, if any, or interest (including
Liquidated Damages, if any) on such Note. For the purposes of this Section 4.8,
the term "junior securities" means (a) shares of any stock of any class of the
Company or (b) securities of the Company that are subordinated in right of
payment to all Senior Indebtedness that may be outstanding at the time of
issuance or delivery of such securities to substantially the same extent as, or
to a greater extent than, the Notes are so subordinated as provided in this
Article Four. Nothing contained in this Article Four 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 Noteholders,
the right, which is absolute and unconditional, of the Holder of any Note to
convert such Note in accordance with Article Fifteen.

     Section 4.9 Article Applicable to Paying Agents. If at any time any paying
                 -----------------------------------
agent other than the Trustee shall have been appointed by the Company and be
then acting hereunder, the term "Trustee" as used in this Article Four shall
(unless the context otherwise requires) be construed as extending to and
including such paying agent within its meaning as fully for all intents and
purposes as if such paying agent were named in this Article Four in addition to
or in place of the Trustee; provided, however, that the first paragraph of
Section 4.5 shall not apply to the Company or any Affiliate of the Company if it
or such Affiliate acts as paying agent.

     The Trustee shall not be responsible for the actions or inactions of any
other paying agents (including the Company if acting as its own paying agent)
and shall have no control of any funds held by such other paying agents.

     Section 4.10 Senior Indebtedness Entitled to Rely. The holders of Senior
                  ------------------------------------
Indebtedness (including, without limitation, Designated Senior Indebtedness)
shall have the right to rely upon this Article Four, and no amendment or
modification of the provisions contained herein shall diminish the rights of
such holders unless such holders shall have agreed in writing thereto.

     Section 4.11 Reliance on Judicial Order or Certificate of Liquidating
                  --------------------------------------------------------
Agent. Upon any payment or distribution of assets of the Company referred to in
-----
this Article Four, the Trustee and the Noteholders shall be entitled to rely
upon any order or decree entered by any court of competent jurisdiction in which
such insolvency, bankruptcy, receivership, liquidation, reorganization,
dissolution, winding up or similar case or proceeding is pending, or a
certificate of the trustee in bankruptcy, liquidating trustee, custodian,
receiver, assignee for the benefit of creditors, agent or other Person making
such payment or distribution, delivered to the Trustee or to the Noteholders,
for the purpose of ascertaining the Persons entitled to participate in such
payment or distribution, the holders of 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 Four.

                                      -33-


<PAGE>

                                  ARTICLE FIVE

                       PARTICULAR COVENANTS OF THE COMPANY

     Section 5.1 Payment of Principal, Premium and Interest. The Company
                 ------------------------------------------
covenants and agrees that it will duly and punctually pay or cause to be paid
the principal of and premium, if any (including the redemption price upon
redemption pursuant to Article Three), and interest (including Liquidated
Damages, if any), on each of the Notes at the places, at the respective times
and in the manner provided herein and in the Notes.

     Section 5.2 Maintenance of Office or Agency. The Company will maintain an
                 -------------------------------
office or agency in the Borough of Manhattan, The City of New York, where the
Notes may be surrendered for registration of transfer or exchange or for
presentation for payment or for conversion or redemption and where notices and
demands to or upon the Company in respect of the Notes and this Indenture may be
served. The Company will give prompt written notice to the Trustee of the
location, and any change in the location, of such office or agency not
designated or appointed by the Trustee. If at any time the Company shall fail to
maintain any such required office or agency or shall fail to furnish the Trustee
with the address thereof, such presentations, surrenders, notices and demands
may be made or served at the Corporate Trust Office of the Trustee at 633 West
5th Street, 12th Floor, Los Angeles, California 90071, Attention: Corporate
Trust Department (Riverstone Networks, Inc. 3 3/4% Convertible Subordinated
Notes due 2006).

     The Company may also from time to time designate co-registrars and one or
more 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. The
Company will give prompt written notice of any such designation or rescission
and of any change in the location of any such other office or agency.

     The Company hereby initially designates the Trustee as paying agent, Note
registrar, Custodian and conversion agent and the Office of State Street Bank
and Trust Company, N.A., 61 Broadway, New York, NY 10006, an Affiliate of
Trustee, Attention: Corporate Trust Department as the office or agency of the
Company for each of the aforesaid purposes.

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

     Section 5.3 Appointments to Fill Vacancies in Trustee's Office. The
                 --------------------------------------------------
Company, whenever necessary to avoid or fill a vacancy in the office of Trustee,
will appoint, in the manner provided in Section 8.10, a Trustee, so that there
shall at all times be a Trustee hereunder.

     Section 5.4 Provisions as to Paying Agent.
                 -----------------------------

          (a) If the Company shall appoint a paying agent other than the
Trustee, or if the Trustee shall appoint such a paying agent, the Company will
cause such paying agent to execute and

                                      -34-

<PAGE>

deliver to the Trustee an instrument in which such agent shall agree with the
Trustee, subject to the provisions of this Section 5.4:

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

               (2) that it will hold all sums held by it as such agent for the
     payment of any cash to be paid by the Company in connection with a
     conversion of Notes into cash in lieu of shares of Common Stock;

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

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

     The Company shall, (i) on or before each due date of the principal of,
premium, if any, or interest on the Notes, deposit with the paying agent a sum
(in funds which are immediately available on the due date for such payment)
sufficient to pay such principal, premium, if any, or interest, and (ii) if the
Company has elected, with proper notice as described in Section 15.2, to pay
cash in lieu of issuing shares of Common Stock upon conversion of the Notes, on
or before the second Business Day following the Conversion Date, deposit with
the paying agent a sum (in funds which are immediately available on the due date
for such payment) sufficient to pay such cash, and (unless such paying agent is
the Trustee) the Company will promptly notify the Trustee of any failure to take
such action; provided, however, that if such deposit is made on the due date,
with respect to principal, premium, if any, or interest, or the second Business
Day following the Conversion Date, with respect to a cash payment in lieu of
conversion, such deposit shall be received by the paying agent by 10:00 a.m. New
York City time, on such date.

          (b) If the Company shall act as its own paying agent, it will, on or
before each due date of the principal of, premium, if any, or interest
(including Liquidated Damages, if any) on the Notes or the second Business Day
following a Conversion Date, as applicable, set aside, segregate and hold in
trust for the benefit of the holders of the Notes a sum sufficient to pay such
principal, premium, if any, or interest (including Liquidated Damages, if any)
so becoming due or the amount of cash due to the holder upon conversion and will
promptly notify the Trustee of any failure to take such action and of any
failure by the Company (or any other obligor under the Notes) to make any
payment of the principal of, premium, if any, or interest (including Liquidated
Damages, if any) on the Notes when the same shall become due and payable.

          (c) Anything in this Section 5.4 to the contrary notwithstanding, the
Company may, at any time, for the purpose of obtaining a satisfaction and
discharge of this Indenture, or for any other reason, pay or cause to be paid to
the Trustee all sums held in trust by the Company or any

                                      -35-

<PAGE>

paying agent hereunder as required by this Section 5.4, such sums to be held by
the Trustee upon the trusts herein contained and upon such payment by the
Company or any paying agent to the Trustee, the Company or such paying agent
shall be released from all further liability with respect to such sums.

          (d) Anything in this Section 5.4 to the contrary notwithstanding, the
agreement to hold sums in trust as provided in this Section 5.4 is subject to
Sections 13.3 and 13.4.

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

     Section 5.5 Existence. Subject to Article Twelve, the Company will do or
                 ---------
cause to be done all things necessary to preserve and keep in full force and
effect its existence and rights (charter and statutory); provided, however, that
the Company shall not be required to preserve any such right if the Company
shall determine that the preservation thereof is no longer desirable in the
conduct of the business of the Company and that the loss thereof is not
disadvantageous in any material respect to the Noteholders.

     Section 5.6 Maintenance of Properties. The Company will cause all
                 -------------------------
properties used or useful in the conduct of its business or the business of any
Significant Subsidiary to be maintained and kept in good condition, repair and
working order and supplied with all necessary equipment and will cause to be
made all necessary repairs, renewals, replacements, betterments and improvements
thereof, all as in the judgment of the Company may be necessary so that the
business carried on in connection therewith may be properly and advantageously
conducted at all times; provided, however, that nothing in this Section shall
prevent the Company from discontinuing the operation or maintenance of any of
such properties if such discontinuance is, in the judgment of the Company,
desirable in the conduct of its business or the business of any subsidiary and
not disadvantageous in any material respect to the Noteholders.

     Section 5.7 Payment of Taxes and Other Claims. The Company will pay or
                 ---------------------------------
discharge, or cause to be paid or discharged, before the same may become
delinquent, (i) all taxes, assessments and governmental charges levied or
imposed upon the Company or any Significant Subsidiary or upon the income,
profits or property of the Company or any Significant Subsidiary, (ii) all
claims for labor, materials and supplies which, if unpaid, might by law become a
lien or charge upon the property of the Company or any Significant Subsidiary
and (iii) all stamps and other duties, if any, which may be imposed by the
United States or any political subdivision thereof or therein in connection with
the issuance, transfer, exchange or conversion of any Notes or with respect to
this Indenture; provided, however, that, in the case of clauses (i) and (ii),
the Company shall not be required to pay or discharge or cause to be paid or
discharged any such tax, assessment, charge or claim (A) if the failure to do so
will not, in the aggregate, have a material adverse impact on the Company, or
(B) if the amount, applicability or validity is being contested in good faith by
appropriate proceedings.

                                      -36-


<PAGE>

     Section 5.8 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 Securities 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 5.9 Stay, Extension and Usury Laws. The Company covenants (to the
                 ------------------------------
extent that it may lawfully do so) that it shall not at any time insist upon,
plead, or in any manner whatsoever claim or take the benefit or advantage of,
any stay, extension or usury law or other law which would prohibit or forgive
the Company from paying all or any portion of the principal of, premium, if any,
or interest (including Liquidated Damages, if any) on the Notes as contemplated
herein, wherever enacted, now or at any time hereafter in force, or which may
affect the covenants or the performance of this Indenture and the Company (to
the extent it may lawfully do so) hereby expressly waives all benefit or
advantage of any such law, and covenants that it will not, by resort to any such
law, hinder, delay or impede the execution of any power herein granted to the
Trustee, but will suffer and permit the execution of every such power as though
no such law had been enacted.

     Section 5.10 Compliance Certificate. The Company shall deliver to the
                  ----------------------
Trustee, within one hundred twenty (120) days after the end of each fiscal year
of the Company, a certificate signed by either the principal executive officer,
principal financial officer or principal accounting officer of the Company,
stating whether or not to the best knowledge of the signer thereof the Company
is in default in the performance and observance of any of the terms, provisions
and conditions of this Indenture (without regard to any period of grace or
requirement of notice provided hereunder) and, if the Company shall be in
default, specifying all such defaults and the nature and the status thereof of
which the signer may have knowledge.

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

     Any notice required to be given under this Section 5.10 shall be delivered
to a Responsible Officer of the Trustee at its Corporate Trust Office.


                                      -37-

<PAGE>

     Section 5.11 Liquidated Damages. If Liquidated Damages are 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
Liquidated Damages that are payable and (ii) the date on which such damages are
payable. Unless and until a Responsible Officer of the Trustee receives such a
certificate, the Trustee may assume without inquiry that no Liquidated Damages
are payable. If the Company has paid Liquidated Damages directly to the persons
entitled to them, the Company shall deliver to the Trustee a certificate setting
forth the particulars of such payment.



                                  ARTICLE SIX

                         NOTEHOLDERS' LISTS AND REPORTS
                         BY THE COMPANY AND THE TRUSTEE

     Section 6.1 Noteholders' Lists. The Company covenants and agrees that it
                 ------------------
will furnish or cause to be furnished to the Trustee, semiannually, not more
than fifteen (15) days after each May 15 and November 15 in each year beginning
with May 15, 2002, and at such other times as the Trustee may request in
writing, within thirty (30) days after receipt by the Company of any such
request (or such lesser time as the Trustee may reasonably request in order to
enable it to timely provide any notice to be provided by it hereunder), a list
in such form as the Trustee may reasonably require of the names and addresses of
the holders of Notes as of a date not more than fifteen (15) days (or such other
date as the Trustee may reasonably request in order to so provide any such
notices) prior to the time such information is furnished, except that no such
list need be furnished by the Company to the Trustee so long as the Trustee is
acting as the sole Note registrar.

     Section 6.2 Preservation and Disclosure of Lists.
                 ------------------------------------

          (a) The Trustee shall preserve, in as current a form as is reasonably
practicable, all information as to the names and addresses of the holders of
Notes contained in the most recent list furnished to it as provided in Section
6.1 or maintained by the Trustee in its capacity as Note registrar or
co-registrar in respect of the Notes, if so acting. The Trustee may destroy any
list furnished to it as provided in Section 6.1 upon receipt of a new list so
furnished.

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

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

     Section 6.3 Reports by Trustee.
                 ------------------

          (a) Within sixty (60) days after May 15 of each year commencing with
the year 2002, the Trustee shall transmit to holders of Notes such reports dated
as of May 15 of the year in which

                                      -38-

<PAGE>

such reports are made concerning the Trustee and its actions under this
Indenture as may be required pursuant to the Trust Indenture Act at the times
and in the manner provided pursuant thereto.

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

     Section 6.4 Reports by Company. The Company shall file with the Trustee
                 ------------------
(and the Commission if at any time after the Indenture becomes qualified under
the Trust Indenture Act), and transmit to holders of Notes, such information,
documents and other reports and such summaries thereof, as may be required
pursuant to the Trust Indenture Act at the times and in the manner provided
pursuant to such Act, whether or not the Notes are governed by such Act;
provided, however, that any such information, documents or reports required to
be filed with the Commission pursuant to Section 13 or 15(d) of the Exchange Act
shall be filed with the Trustee within fifteen (15) days after the same is so
required to be filed with the Commission. Delivery of such reports, information
and documents to the Trustee is for informational purposes only and the
Trustee's receipt of such shall not constitute constructive notice of any
information contained therein or determinable from information contained
therein, including the Company's compliance with any of its covenants hereunder
(as to which the Trustee is entitled to rely exclusively on Officers'
Certificates).



                                 ARTICLE SEVEN

                           REMEDIES OF THE TRUSTEE AND
                       NOTEHOLDERS ON AN EVENT OF DEFAULT

     Section 7.1 Events of Default. In case one or more of the following Events
                 -----------------
of Default (whatever the reason for such Event of Defaut and whether it shall
be voluntary or involuntary or be effected by operation of law or pursuant to
any judgment, decree or order of any court or any order, rule or regulation of
any administrative or governmental body) shall have occurred and be continuing:

          (a) default in the payment of any installment of interest (including
Liquidated Damages, if any) upon any of the Notes as and when the same shall
become due and payable, and continuance of such default for a period of thirty
(30) days, whether or not such payment is permitted under Article Four hereof;
or

          (b) default in the payment of the principal of or premium, if any, on
any of the Notes or in any payment of cash required to be made in lieu of
conversion of the Notes into Common Stock, as and when the same shall become due
and payable either at maturity or in connection with any redemption pursuant to
Article Three or conversion pursuant to Article Fifteen, by acceleration or
otherwise, whether or not such payment is permitted under Article Four hereof;
or

                                      -39-

<PAGE>

          (c) failure on the part of the Company duly to observe or perform any
other of the covenants or agreements on the part of the Company in the Notes or
in this Indenture (other than a covenant or agreement a default in whose
performance or whose breach is elsewhere in this Section 7.1 specifically dealt
with) continued for a period of sixty (60) days after the date on which written
notice of such failure, requiring the Company to remedy the same, shall have
been given to the Company by the Trustee, or the Company and a Responsible
Officer of the Trustee by the holders of at least twenty-five percent (25%) in
aggregate principal amount of the Notes at the time outstanding determined in
accordance with Section 9.4; or

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

          (e) an involuntary case or other proceeding shall be commenced against
the Company or any Significant Subsidiary seeking liquidation, reorganization or
other relief with respect to it or any Significant Subsidiary or its or such
Significant Subsidiary's debts under any bankruptcy, insolvency or other similar
law now or hereafter in effect or seeking the appointment of a trustee,
receiver, liquidator, custodian or other similar official of it or any
Significant Subsidiary or any substantial part of the property of the Company or
any Significant Subsidiary, and such involuntary case or other proceeding shall
remain undismissed and unstayed for a period of ninety (90) consecutive days;

then, and in each and every such case (other than an Event of Default specified
in Section 7.1(d) or (e) with respect to the Company), unless the principal of
all of the Notes shall have already become due and payable, either the Trustee
or the holders of not less than twenty-five percent (25%) in aggregate principal
amount of the Notes then outstanding hereunder determined in accordance with
Section 9.4, by notice in writing to the Company (and to the Trustee if given by
Noteholders), may declare the principal of and premium, if any, on all the Notes
and the interest accrued thereon (including Liquidated Damages, if any) to be
due and payable immediately, and upon any such declaration the same shall become
and shall be immediately due and payable, anything in this Indenture or in the
Notes contained to the contrary notwithstanding. If an Event of Default
specified in Section 7.1(d) or (e) with respect to the Company occurs, the
principal of all the Notes and the interest accrued thereon shall (including
Liquidated Damages, if any) be immediately and automatically due and payable
without necessity of further action. This provision, however, is subject to the
conditions that if, at any time after the principal of the Notes shall have been
so declared due and payable, and before any judgment or decree for the payment
of the monies due shall have been obtained or entered as hereinafter provided,
the Company shall pay or shall deposit with the Trustee a sum sufficient to pay
all matured installments of interest upon (including

                                      -40-

<PAGE>

Liquidated Damages, if any) all Notes and the principal of and premium, if any,
on any and all Notes which shall have become due otherwise than by acceleration
(with interest on overdue installments of interest (including Liquidated
Damages, if any) (to the extent that payment of such interest is enforceable
under applicable law) and on such principal and premium, if any, at the rate
borne by the Notes, to the date of such payment or deposit) and amounts due to
the Trustee pursuant to Section 8.6, and if any and all defaults under this
Indenture, other than the nonpayment of principal of and premium, if any, and
accrued interest on (including Liquidated Damages, if any) Notes which shall
have become due by acceleration, shall have been cured or waived pursuant to
Section 7.7, then and in every such case the holders of a majority in aggregate
principal amount of the Notes then outstanding, by written notice to the Company
and to the Trustee, may waive all defaults or Events of Default and rescind and
annul such declaration and its consequences; but no such waiver or rescission
and annulment shall extend to or shall affect any subsequent default or Event of
Default, or shall impair any right consequent thereon. The Company shall notify
a Responsible Officer of the Trustee, promptly (and in any event within five
Business Days) upon becoming aware thereof, of any Event of Default.

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

     Section 7.2 Payments of Notes on Default; Suit Therefor. The Company
                 -------------------------------------------
covenants that (a) in case default shall be made in the payment of any
installment of interest upon (including Liquidated Damages, if any) any of the
Notes as and when the same shall become due and payable, and such default shall
have continued for a period of thirty (30) days, or (b) in case default shall be
made in the payment of the principal of or premium, if any, on any of the Notes
as and when the same shall have become due and payable, whether at maturity of
the Notes or in connection with any redemption, or in any payment of cash
required to be made in lieu of conversion of the Notes into Common Stock, by or
under this Indenture declaration or otherwise, then, upon demand of the Trustee,
the Company will pay to the Trustee, for the benefit of the holders of the
Notes, the whole amount that then shall have become due and payable on all such
Notes for principal and premium, if any, interest (including Liquidated Damages,
if any), or conversion, as the case may be, with interest upon the overdue
principal and premium, if any, and (to the extent that payment of such interest
is enforceable under applicable law) upon the overdue installments of interest
(including Liquidated Damages, if any) at the rate borne by the Notes, and, in
addition thereto, such further amount as shall be sufficient to cover the costs
and expenses of collection, including reasonable compensation to the Trustee,
its agents, attorneys and counsel, and all other amounts due the Trustee under
Section 8.6. Until such demand by the Trustee, the Company may pay the principal
of and premium, if any, interest (including Liquidated Damages, if any) and cash
payment upon conversion of the Notes to the registered holders, whether or not
the Notes are overdue.

                                      -41-


<PAGE>

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

     In case there shall be pending proceedings for the bankruptcy or for the
reorganization of the Company or any other obligor on the Notes under Title 11
of the United States Code, or any other applicable law, or in case a receiver,
assignee or trustee in bankruptcy or reorganization, liquidator, sequestrator or
similar official shall have been appointed for or taken possession of the
Company or such other obligor, the property of the Company or such other
obligor, or in the case of any other judicial proceedings relative to the
Company or such other obligor upon the Notes, or to the creditors or property of
the Company or such other obligor, the Trustee, irrespective of whether the
principal of the Notes shall then be due and payable as therein expressed or by
declaration or otherwise and irrespective of whether the Trustee shall have made
any demand pursuant to the provisions of this Section 7.2, shall be entitled and
empowered, by intervention in such proceedings or otherwise, to file and prove a
claim or claims for the whole amount of principal, premium, if any, and interest
(including Liquidated Damages, if any) owing and unpaid in respect of the Notes,
and, in case of any judicial proceedings, to file such proofs of claim and other
papers or documents as may be necessary or advisable in order to have the claims
of the Trustee and of the Noteholders allowed in such judicial proceedings
relative to the Company or any other obligor on the Notes, its or their
creditors, or its or their property, and to collect and receive any monies or
other property payable or deliverable on any such claims, and to distribute the
same after the deduction of any amounts due the Trustee under Section 8.6, and
any receiver, assignee or trustee in bankruptcy or reorganization, liquidator,
custodian or similar official is hereby authorized by each of the Noteholders 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 Noteholders, to pay to
the Trustee any amount due it for reasonable compensation, expenses, advances
and disbursements, including counsel fees incurred by it up to the date of such
distribution. To the extent that such payment of reasonable compensation,
expenses, advances and disbursements out of the estate in any such proceedings
shall be denied for any reason, payment of the same shall be secured by a lien
on, and shall be paid out of, any and all distributions, dividends, monies,
securities and other property which the holders of the Notes may be entitled to
receive in such proceedings, whether in liquidation or under any plan of
reorganization or arrangement or otherwise.

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

                                      -42-


<PAGE>

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

     Section 7.3 Application of Monies Collected by Trustee. Any monies
                 ------------------------------------------
collected by the Trustee pursuant to this Article Seven shall be applied in the
order following, at the date or dates fixed by the Trustee for the distribution
of such monies, upon presentation of the several Notes, and stamping thereon the
payment, if only partially paid, and upon surrender thereof, if fully paid:

          FIRST: To the payment of all amounts due the Trustee under Section
     8.6;

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

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

          FOURTH: Subject to the provisions of Article Four, to the payment of
     the remainder, if any, to the Company or any other Person lawfully entitled
     thereto.

     Section 7.4 Proceedings by Noteholder. No holder of any Note shall have any
                 -------------------------
right by virtue of or by reference to any provision of this Indenture to
institute any suit, action or proceeding in equity or at law upon or under or
with respect to this Indenture, or for the appointment of a receiver, trustee,
liquidator, custodian or other similar official, or for any other remedy
hereunder, unless such holder previously shall have given to the Trustee written
notice of an Event of Default and of the continuance thereof, as hereinbefore
provided, and unless also the holders of not less than twenty-five percent (25%)
in aggregate principal amount of the Notes then outstanding shall have made

                                      -43-

<PAGE>

written request upon the Trustee to institute such action, suit or proceeding in
its own name as Trustee hereunder and shall have offered to the Trustee such
indemnity as it may require against the costs, expenses and liabilities to be
incurred therein or thereby, and the Trustee for sixty (60) days after its
receipt of such notice, request and offer of indemnity, shall have neglected or
refused to institute any such action, suit or proceeding and no direction
inconsistent with such written request shall have been given to the Trustee
pursuant to Section 7.7; it being understood and intended, and being expressly
covenanted by the taker and holder of every Note with every other taker and
holder and the Trustee, that no one or more holders of Notes shall have any
right in any manner whatever by virtue of or by reference to any provision of
this Indenture to affect, disturb or prejudice the rights of any other holder of
Notes, or to obtain or seek to obtain priority over or preference to any other
such holder, or to enforce any right under this Indenture, except in the manner
herein provided and for the equal, ratable and common benefit of all holders of
Notes (except as otherwise provided herein). For the protection and enforcement
of this Section 7.4, each and every Noteholder and the Trustee shall be entitled
to such relief as can be given either at law or in equity.

     Notwithstanding any other provision of this Indenture and any provision of
any Note, the right of any holder of any Note to receive payment of the
principal of and premium, if any (including the redemption price upon redemption
pursuant to Article Three), accrued interest (including Liquidated Damages, if
any) and cash payment upon conversion of such Note in lieu of conversion into
Common Stock, on or after the respective due dates expressed in such Note or in
the event of redemption or conversion, or to institute suit for the enforcement
of any such payment on or after such respective dates against the Company shall
not be impaired or affected without the consent of such holder, except for the
Company's rights to revoke or otherwise terminate the Cash Conversion Notice in
accordance with the terms of this Indenture.

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

     Section 7.5 Proceedings by Trustee. In case of an Event of Default, the
                 ----------------------
Trustee may, in its discretion, proceed to protect and enforce the rights vested
in it by this Indenture by such appropriate judicial proceedings as are
necessary to protect and enforce any of such rights, either by suit in equity or
by action at law or by proceeding in bankruptcy or otherwise, whether for the
specific enforcement of any covenant or agreement contained in this Indenture or
in aid of the exercise of any power granted in this Indenture, or to enforce any
other legal or equitable right vested in the Trustee by this Indenture or by
law.

     Section 7.6 Remedies Cumulative and Continuing. Except as provided in
                 ----------------------------------
Section 2.6, all powers and remedies given by this Article Seven to the Trustee
or to the Noteholders shall, to the extent permitted by law, be deemed
cumulative and not exclusive of any thereof or of any other powers and remedies
available to the Trustee or the holders of the Notes, by judicial proceedings or
otherwise, to enforce the performance or observance of the covenants and
agreements contained in this Indenture, and no delay or omission of the Trustee
or of any holder of any of the Notes to

                                      -44-

<PAGE>

exercise any right or power accruing upon any default or Event of Default
occurring and continuing as aforesaid shall impair any such right or power, or
shall be construed to be a waiver of any such default or any acquiescence
therein, and, subject to the provisions of Section 7.4, every power and remedy
given by this Article Seven or by law to the Trustee or to the Noteholders may
be exercised from time to time, and as often as shall be deemed expedient, by
the Trustee or by the Noteholders.

     Section 7.7 Direction of Proceedings and Waiver of Defaults by Majority of
                 --------------------------------------------------------------
Noteholders. The holders of a majority in aggregate principal amount of the
-----------
Notes at the time outstanding determined in accordance with Section 9.4 shall
have the right to direct the time, method and place of conducting any proceeding
for any remedy available to the Trustee or exercising any trust or power
conferred on the Trustee; provided, however, that (a) such direction shall not
be in conflict with any rule of law or with this Indenture, (b) the Trustee may
take any other action which is not inconsistent with such direction and (c) the
Trustee may decline to take any action that would benefit some Noteholder to the
detriment of other Noteholders. The holders of a majority in aggregate principal
amount of the Notes at the time outstanding determined in accordance with
Section 9.4 may, on behalf of the holders of all of the Notes, waive any past
default or Event of Default hereunder and its consequences except (i) a default
in the payment of interest (including Liquidated Damages, if any) or premium, if
any, on, or the principal of, the Notes, (ii) a failure by the Company to
convert any Notes, (iii) a default in the payment of redemption price pursuant
to Article Three or (iv) a default in respect of a covenant or provisions hereof
which under Article Eleven cannot be modified or amended without the consent of
the holders of each or all Notes then outstanding or affected thereby. Upon any
such waiver, the Company, the Trustee and the holders of the Notes shall be
restored to their former positions and rights hereunder; but no such waiver
shall extend to any subsequent or other default or Event of Default or impair
any right consequent thereon. Whenever any default or Event of Default hereunder
shall have been waived as permitted by this Section 7.7, said default or Event
of Default shall for all purposes of the Notes and this Indenture be deemed to
have been cured and to be not continuing; but no such waiver shall extend to any
subsequent or other default or Event of Default or impair any right consequent
thereon.

     Section 7.8 Notice of Defaults. The Trustee shall, within ninety (90) days
                 ------------------
after a Responsible Officer of the Trustee has actual knowledge of the
occurrence of a default, mail to all Noteholders, as the names and addresses of
such holders appear upon the Note register, notice of all defaults actually
known to a Responsible Officer, unless such defaults shall have been cured or
waived before the giving of such notice; provided, however, that except in the
case of default in the payment of the principal of, or premium, if any, or
interest (including Liquidated Damages, if any) on any of the Notes, the Trustee
shall be protected in withholding such notice if and so long as a trust
committee of directors and/or Responsible Officers of the Trustee in good faith
determines that the withholding of such notice is in the interests of the
Noteholders.

     Section 7.9 Undertaking to Pay Costs. All parties to this Indenture agree,
                 ------------------------
and each holder of any Note by his acceptance thereof shall be deemed to have
agreed, that any court may, in its discretion, require, in any suit for the
enforcement of any right or remedy under this Indenture, or in any suit against
the Trustee for any action taken or omitted by it as Trustee, the filing by any
party litigant in such suit of an undertaking to pay the costs of such suit and
that such court may in its

                                      -45-

<PAGE>

discretion assess reasonable costs, including reasonable attorneys' fees and
expenses, against any party litigant in such suit, having due regard to the
merits and good faith of the claims or defenses made by such party litigant;
provided, however, that the provisions of this Section 7.9 (to the extent
permitted by law) shall not apply to any suit instituted by the Trustee, to any
suit instituted by any Noteholder, or group of Noteholders, holding in the
aggregate more than ten percent in principal amount of the Notes at the time
outstanding determined in accordance with Section 9.4, or to any suit instituted
by any Noteholder for the enforcement of the payment of the principal of or
premium, if any, or interest on any Note on or after the due date expressed in
such Note or to any suit for the enforcement of the right to convert any Note in
accordance with the provisions of Article Fifteen.



                                  ARTICLE EIGHT

                                   THE TRUSTEE

     Section 8.1 Duties and Responsibilities of Trustee. The Trustee, prior to
                 --------------------------------------
the occurrence of an Event of Default and after the curing of all Events of
Default which may have occurred, undertakes to perform such duties and only such
duties as are specifically set forth in this Indenture. In case an Event of
Default has occurred (which has not been cured or waived), the Trustee shall
exercise such of the rights and powers vested in it by this Indenture, and use
the same degree of care and skill in their exercise, as a prudent person would
exercise or use under the circumstances in the conduct of his own affairs.

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

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

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

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

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

                                      -46-


<PAGE>

          (c) the Trustee shall not be liable with respect to any action taken
or omitted to be taken by it in good faith in accordance with the written
direction of the holders of not less than a majority in principal amount of the
Notes at the time outstanding determined as provided in Section 9.4 relating to
the time, method and place of conducting any proceeding for any remedy available
to the Trustee, or exercising any trust or power conferred upon the Trustee,
under this Indenture;

          (d) whether or not therein provided, every provision of this Indenture
relating to the conduct or affecting the liability of, or affording protection
to, the Trustee shall be subject to the provisions of this Section;

          (e) the Trustee shall not be liable in respect of any payment (as to
the correctness of amount, entitlement to receive or any other matters relating
to payment) or notice effected by the Company or any paying agent or any records
maintained by any co-registrar with respect to the Notes; and

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

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

     Section 8.2 Reliance on Documents, Opinions, Etc. Except as otherwise
                 ------------------------------------
provided in Section 8.1:

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

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

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

                                      -47-


<PAGE>

          (d) the Trustee shall be under no obligation to exercise any of the
rights or powers vested in it by this Indenture at the request, order or
direction of any of the Noteholders pursuant to the provisions of this
Indenture, unless such Noteholders shall have offered to the Trustee reasonable
security or indemnity against the costs, expenses and liabilities which may be
incurred therein or thereby;

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

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

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

     Section 8.3 No Responsibility for Recitals, Etc. The recitals contained
                 -----------------------------------
herein and in the Notes (except in the Trustee's certificate of authentication)
shall be taken as the statements of the Company, and the Trustee assumes no
responsibility for the correctness of the same. The Trustee makes no
representations as to the validity or sufficiency of this Indenture or of the
Notes. The Trustee shall not be accountable for the use or application by the
Company of any Notes or the proceeds of any Notes authenticated and delivered by
the Trustee in conformity with the provisions of this Indenture.

     Section 8.4 Trustee, Paying Agents, Conversion Agents or Registrar May Own
                 --------------------------------------------------------------
Notes. The Trustee, any paying agent, any conversion agent or Note registrar, in
-----
its individual or any other capacity, may become the owner or pledgee of Notes
with the same rights it would have if it were not Trustee, paying agent,
conversion agent or Note registrar.

     Section 8.5 Monies to be Held in Trust. Subject to the provisions of
                 --------------------------
Section 13.4 and Section 4.2, all monies received by the Trustee shall, until
used or applied as herein provided, be held in trust for the purposes for which
they were received. Money held by the Trustee in trust hereunder need not be
segregated from other funds except to the extent required by law. The Trustee
shall be under no liability for interest on any money received by it hereunder
except as may be agreed in writing from time to time by the Company and the
Trustee.

                                      -48-


<PAGE>

     Section 8.6 Compensation and Expenses of Trustee. The Company covenants and
                 ------------------------------------
agrees to pay to the Trustee from time to time, and the Trustee shall be
entitled to, reasonable compensation for all services rendered by it hereunder
in any capacity (which shall not be limited by any provision of law in regard to
the compensation of a trustee of an express trust) as mutually agreed to from
time to time in writing between the Company and the Trustee, and the Company
will pay or reimburse the Trustee upon its request for all expenses,
disbursements and advances reasonably incurred or made by the Trustee in
accordance with any of the provisions of this Indenture (including the
reasonable compensation and the expenses and disbursements of its counsel and of
all Persons not regularly in its employ) except any such expense, disbursement
or advance as may arise from its negligence or willful misconduct. The Company
also covenants to fully indemnify the Trustee (or any officer, director or
employee of the Trustee) and any predecessor Trustee, in any capacity under this
Indenture and its agents and any authenticating agent for, and to hold them
harmless against, any and all loss, liability, claim, damage or expense
(including taxes other than taxes based on the income of the Trustee) incurred
without negligence or willful misconduct on the part of the Trustee or such
officers, directors, employees and agent or authenticating agent, as the case
may be, and arising out of or in connection with the acceptance or
administration of this trust or in any other capacity hereunder, including the
costs and expenses of defending themselves against any claim of liability in the
premises. The obligations of the Company under this Section 8.6 to compensate or
indemnify the Trustee and to pay or reimburse the Trustee for expenses,
disbursements and advances shall be secured by a lien prior to that of the Notes
upon all property and funds held or collected by the Trustee as such, except
funds held in trust for the benefit of the holders of particular Notes. The
obligation of the Company under this Section shall survive the resignation or
removal of the Trustee and the satisfaction and discharge of this Indenture.

     When the Trustee and its agents and any authenticating agent incur expenses
or render services after an Event of Default specified in Section 7.1(d) or (e)
with respect to the Company occurs, the expenses and the compensation for the
services are intended to constitute expenses of administration under any
bankruptcy, insolvency or similar laws.

     Section 8.7 Officers' Certificate as Evidence. Except as otherwise provided
                 ---------------------------------
in Section 8.1, whenever in the administration of the provisions of this
Indenture the Trustee shall deem it necessary or desirable that a matter be
proved or established prior to taking or omitting any action hereunder, such
matter (unless other evidence in respect thereof be herein specifically
prescribed) may, in the absence of negligence or willful misconduct on the part
of the Trustee, be deemed to be conclusively proved and established by an
Officers' Certificate delivered to the Trustee.

     Section 8.8 Conflicting Interests of Trustee. If the Trustee has or shall
                 --------------------------------
acquire a conflicting interest within the meaning of the Trust Indenture Act,
the Trustee shall either eliminate such interest or resign, to the extent and in
the manner provided by, and subject to the provisions of, the Trust Indenture
Act and this Indenture.

     Section 8.9 Eligibility of Trustee. There shall at all times be a Trustee
                 ----------------------
hereunder which shall be a Person that is eligible pursuant to the Trust
Indenture Act to act as such and has a combined capital and surplus of at least
$50,000,000 (or if such Person is a member of a bank holding

                                      -49-

<PAGE>

company system, its bank holding company shall have a combined capital and
surplus of at least $50,000,000). If such Person publishes reports of condition
at least annually, pursuant to law or to the requirements of any supervising or
examining authority, then for the purposes of this Section, the combined capital
and surplus of such Person shall be deemed to be its combined capital and
surplus as set forth in its most recent report of condition so published. If at
any time the Trustee shall cease to be eligible in accordance with the
provisions of this Section 8.9, it shall resign immediately in the manner and
with the effect hereinafter specified in this Article.

     Section 8.10 Resignation or Removal of Trustee.
                  ---------------------------------

          (a) The Trustee may at any time resign by giving written notice of
such resignation to the Company and to the holders of Notes. Upon receiving such
notice of resignation, the Company shall promptly appoint a successor trustee by
written instrument, in duplicate, executed by order of the Board of Directors,
one copy of which instrument shall be delivered to the resigning Trustee and one
copy to the successor trustee. If no successor trustee shall have been so
appointed and have accepted appointment sixty (60) days after the mailing of
such notice of resignation to the Noteholders, the resigning Trustee may, upon
ten (10) business days' notice to the Company and the Noteholders, appoint a
successor identified in such notice or may petition, at the expense of the
Company, any court of competent jurisdiction for the appointment of a successor
trustee, or, if any Noteholder who has been a bona fide holder of a Note or
Notes for at least six (6) months may, subject to the provisions of Section 7.9,
on behalf of himself and all others similarly situated, petition any such court
for the appointment of a successor trustee. Such court may thereupon, after such
notice, if any, as it may deem proper and prescribe, appoint a successor
trustee.

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

               (1) the Trustee shall fail to comply with Section 8.8 after
          written request therefor by the Company or by any Noteholder who has
          been a bona fide holder of a Note or Notes for at least six (6)
          months; or

               (2) the Trustee shall cease to be eligible in accordance with the
          provisions of Section 8.9 and shall fail to resign after written
          request therefor by the Company or by any such Noteholder; or

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

then, in any such case, the Company may remove the Trustee and appoint a
successor trustee by written instrument, in duplicate, executed by order of the
Board of Directors, one copy of which instrument shall be delivered to the
Trustee so removed and one copy to the successor trustee, or, subject to the
provisions of Section 7.9, any Noteholder who has been a bona fide holder of a
Note or Notes for at least six (6) months may, on behalf of himself and all
others similarly situated, petition any court of competent jurisdiction for the
removal of the Trustee and the appointment of a

                                      -50-

<PAGE>

successor trustee; provided, however, that if no successor Trustee shall have
been appointed and have accepted appointment sixty (60) days after either the
Company or the Noteholders has removed the Trustee, the Trustee so removed may
petition any court of competent jurisdiction for an appointment of a successor
trustee. Such court may thereupon, after such notice, if any, as it may deem
proper and prescribe, remove the Trustee and appoint a successor trustee.

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

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

     Section 8.11 Acceptance by Successor Trustee. Any successor trustee
                  -------------------------------
appointed as provided in Section 8.10 shall execute, acknowledge and deliver to
the Company and to its predecessor trustee an instrument accepting such
appointment hereunder, and thereupon the resignation or removal of the
predecessor trustee shall become effective and such successor trustee, without
any further act, deed or conveyance, shall become vested with all the rights,
powers, duties and obligations of its predecessor hereunder, with like effect as
if originally named as trustee herein; but, nevertheless, on the written request
of the Company or of the successor trustee, the trustee ceasing to act shall,
upon payment of any amount then due it and its agents and counsel pursuant to
the provisions of Section 8.6, execute and deliver an instrument transferring to
such successor trustee all the rights and powers of the trustee so ceasing to
act. Upon request of any such successor trustee, the Company shall execute any
and all instruments in writing for more fully and certainly vesting in and
confirming to such successor trustee all such rights and powers. Any trustee
ceasing to act shall, nevertheless, retain a lien upon all property and funds
held or collected by such trustee as such, except for funds held in trust for
the benefit of holders of particular Notes, to secure any amounts then due it
pursuant to the provisions of Section 8.6.

     No successor trustee shall accept appointment as provided in this Section
8.11 unless, at the time of such acceptance, such successor trustee shall be
qualified under the provisions of Section 8.8 and be eligible under the
provisions of Section 8.9.

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

                                      -51-


<PAGE>

     Section 8.12 Succession by Merger, Etc. Any corporation into which the
                  -------------------------
Trustee may be merged or converted or with which it may be consolidated, or any
corporation resulting from any merger, conversion or consolidation to which the
Trustee shall be a party, or any corporation succeeding to all or substantially
all of the corporate trust business of the Trustee (including any trust created
by this Indenture), shall be the successor to the Trustee hereunder without the
execution or filing of any paper or any further act on the part of any of the
parties hereto, provided that in the case of any corporation succeeding to all
or substantially all of the corporate trust business of the Trustee, such
corporation shall be qualified under the provisions of Section 8.8 and eligible
under the provisions of Section 8.9.

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

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

     Section 8.14 Trustee's Application for Instructions from the Company. Any
                  -------------------------------------------------------
application by the Trustee for written instructions from the Company (other than
with regard to any action proposed to be taken or omitted to be taken by the
Trustee that affects the rights of the holders of the Notes or holders of Senior
Indebtedness under this Indenture, including, without limitation, under Article
Four hereof) may, at the option of the Trustee, set forth in writing any action
proposed to be taken or omitted by the Trustee under this Indenture and the date
on and/or after which such action shall be taken or such omission shall be
effective. The Trustee shall not be liable for any action taken by, or omission
of, the Trustee in accordance with a proposal included in such application on or
after the date specified in such application (which date shall not be less than
three (3) Business Days after the date any officer of the Company actually
receives such application, unless any such officer shall have consented in
writing to any earlier date) unless prior to taking any such action (or the
effective date in the case of an omission), the Trustee shall have received
written instructions in response to such application specifying the action to be
taken or omitted.

                                      -52-


<PAGE>

                                  ARTICLE NINE

                                 THE NOTEHOLDERS

     Section 9.1 Action by Noteholders. Whenever in this Indenture it is
                 ---------------------
provided that the holders of a specified percentage in aggregate principal
amount of the Notes may take any action (including the making of any demand or
request, the giving of any notice, consent or waiver or the taking of any other
action), the fact that at the time of taking any such action, the holders of
such specified percentage have joined therein may be evidenced (a) by any
instrument or any number of instruments of similar tenor executed by Noteholders
in person or by agent or proxy appointed in writing, or (b) by the record of the
holders of Notes voting in favor thereof at any meeting of Noteholders duly
called and held in accordance with the provisions of Article Ten, or (c) by a
combination of such instrument or instruments and any such record of such a
meeting of Noteholders. Whenever the Company or the Trustee solicits the taking
of any action by the holders of the Notes, the Company or the Trustee may fix in
advance of such solicitation, a date as the record date for determining holders
entitled to take such action. The record date shall be not more than fifteen
(15) days prior to the date of commencement of solicitation of such action.

     Section 9.2 Proof of Execution by Noteholders. Subject to the provisions of
                 ---------------------------------
Sections 8.1, 8.2 and 10.5, proof of the execution of any instrument by a
Noteholder or its agent or proxy shall be sufficient if made in accordance with
such reasonable rules and regulations as may be prescribed by the Trustee or in
such manner as shall be satisfactory to the Trustee. The holding of Notes shall
be proved by the registry of such Notes or by a certificate of the Note
registrar.

     The record of any Noteholders' meeting shall be proved in the manner
provided in Section 10.6.

     Section 9.3 Who Are Deemed Absolute Owners. The Company, the Trustee, any
                 ------------------------------
paying agent, any conversion agent and any Note registrar may deem the Person in
whose name such Note shall be registered upon the Note register to be, and may
treat it as, the absolute owner of such Note (whether or not such Note shall be
overdue and notwithstanding any notation of ownership or other writing thereon
made by any Person other than the Company or any Note registrar) for the purpose
of receiving payment of or on account of the principal of, premium, if any, and
interest on such Note, for conversion of such Note and for all other purposes;
and neither the Company nor the Trustee nor any paying agent nor any conversion
agent nor any Note registrar shall be affected by any notice to the contrary.
All such payments so made to any holder for the time being, or upon his order,
shall be valid, and, to the extent of the sum or sums so paid, effectual to
satisfy and discharge the liability for monies payable upon any such Note.

     Section 9.4 Company-Owned Notes Disregarded. In determining whether the
                 -------------------------------
holders of the requisite aggregate principal amount of Notes have concurred in
any direction, consent, waiver or other action under this Indenture, Notes which
are owned by the Company or any other obligor on the Notes or any Affiliate of
the Company or any other obligor on the Notes shall be disregarded and deemed
not to be outstanding for the purpose of any such determination; provided,
however, that, for the purposes of determining whether the Trustee shall be
protected in relying on any such direction,

                                      -53-

<PAGE>

consent, waiver or other action, only Notes which a Responsible Officer knows
are so owned shall be so disregarded. Notes so owned which have been pledged in
good faith may be regarded as outstanding for the purposes of this Section 9.4
if the pledgee shall establish to the satisfaction of the Trustee the pledgee's
right to vote such Notes and that the pledgee is not the Company, any other
obligor on the Notes or any Affiliate of the Company or any such other obligor.
In the case of a dispute as to such right, any decision by the Trustee taken
upon the advice of counsel shall be full protection to the Trustee. Upon request
of the Trustee, the Company shall furnish to the Trustee promptly an Officers'
Certificate listing and identifying all Notes, if any, known by the Company to
be owned or held by or for the account of any of the above described Persons,
and, subject to Section 8.1, the Trustee shall be entitled to accept such
Officers' Certificate as conclusive evidence of the facts therein set forth and
of the fact that all Notes not listed therein are outstanding for the purpose of
any such determination.

     Section 9.5 Revocation of Consents; Future Holders Bound. At any time prior
                 --------------------------------------------
to (but not after) the evidencing to the Trustee, as provided in Section 9.1, of
the taking of any action by the holders of the percentage in aggregate principal
amount of the Notes specified in this Indenture in connection with such action,
any holder of a Note which is shown by the evidence to be included in the Notes
the holders of which have consented to such action may, by filing written notice
with the Trustee at its Corporate Trust Office and upon proof of holding as
provided in Section 9.2, revoke such action so far as concerns such Note. Except
as aforesaid, any such action taken by the holder of any Note shall be
conclusive and binding upon such holder and upon all future holders and owners
of such Note and of any Notes issued in exchange or substitution therefor,
irrespective of whether any notation in regard thereto is made upon such Note or
any Note issued in exchange or substitution therefor.



                                  ARTICLE TEN

                             MEETINGS OF NOTEHOLDERS

     Section 10.1 Purpose of Meetings. A meeting of Noteholders may be called at
                  -------------------
any time and from time to time pursuant to the provisions of this Article Ten
for any of the following purposes:

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

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

          (3) to consent to the execution of an indenture or indentures
     supplemental hereto pursuant to the provisions of Section 11.2; or

                                      -54-

<PAGE>

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

     Section 10.2 Call of Meetings by Trustee. The Trustee may at any time call
                  ---------------------------
a meeting of Noteholders to take any action specified in Section 10.1, to be
held at such time and at such place as the Trustee shall determine. Notice of
every meeting of the Noteholders, setting forth the time and the place of such
meeting and in general terms the action proposed to be taken at such meeting and
the establishment of any record date pursuant to Section 9.1, shall be mailed to
holders of Notes at their addresses as they shall appear on the Note register.
Such notice shall also be mailed to the Company. Such notices shall be mailed
not less than twenty (20) nor more than ninety (90) days prior to the date fixed
for the meeting.

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

     Section 10.3 Call of Meetings by Company or Noteholders. In case at any
                  ------------------------------------------
time the Company, pursuant to a resolution of its Board of Directors, or the
holders of at least ten percent (10%) in aggregate principal amount of the Notes
then outstanding, shall have requested the Trustee to call a meeting of
Noteholders, by written request setting forth in reasonable detail the action
proposed to be taken at the meeting, and the Trustee shall not have mailed the
notice of such meeting within twenty (20) days after receipt of such request,
then the Company or such Noteholders may determine the time and the place for
such meeting and may call such meeting to take any action authorized in Section
10.1, by mailing notice thereof as provided in Section 10.2.

     Section 10.4 Qualifications for Voting. To be entitled to vote at any
                  -------------------------
meeting of Noteholders a person shall (a) be a holder of one or more Notes on
the record date pertaining to such meeting or (b) be a person appointed by an
instrument in writing as proxy by a holder of one or more Notes on the record
date pertaining to such meeting. The only persons who shall be entitled to be
present or to speak at any meeting of Noteholders shall be the persons entitled
to vote at such meeting and their counsel and any representatives of the Trustee
and its counsel and any representatives of the Company and its counsel.

     Section 10.5 Regulations. Notwithstanding any other provisions of this
                  -----------
Indenture, the Trustee may make such reasonable regulations as it may deem
advisable for any meeting of Noteholders, in regard to proof of the holding of
Notes and of the appointment of proxies, and in regard to the appointment and
duties of inspectors of votes, the submission and examination of proxies,
certificates and other evidence of the right to vote, and such other matters
concerning the conduct of the meeting as it shall think fit.

     The Trustee shall, by an instrument in writing, appoint a temporary
chairman of the meeting, unless the meeting shall have been called by the
Company or by Noteholders as provided in Section 10.3, in which case the Company
or the Noteholders calling the meeting, as the case may be,

                                      -55-

<PAGE>

shall in like manner appoint a temporary chairman. A permanent chairman and a
permanent secretary of the meeting shall be elected by vote of the holders of a
majority in principal amount of the Notes represented at the meeting and
entitled to vote at the meeting.

     Subject to the provisions of Section 9.4, at any meeting each Noteholder or
proxyholder shall be entitled to one vote for each $1,000 principal amount of
Notes held or represented by him; provided, however, that no vote shall be cast
or counted at any meeting in respect of any Note challenged as not outstanding
and ruled by the chairman of the meeting to be not outstanding. The chairman of
the meeting shall have no right to vote other than by virtue of Notes held by
him or instruments in writing as aforesaid duly designating him as the proxy to
vote on behalf of other Noteholders. Any meeting of Noteholders duly called
pursuant to the provisions of Section 10.2 or 10.3 may be adjourned from time to
time by the holders of a majority of the aggregate principal amount of Notes
represented at the meeting, whether or not constituting a quorum, and the
meeting may be held as so adjourned without further notice.

     Section 10.6 Voting. The vote upon any resolution submitted to any meeting
                  ------
of Noteholders shall be by written ballot on which shall be subscribed the
signatures of the holders of Notes or of their representatives by proxy and the
outstanding principal amount of the Notes held or represented by them. The
permanent chairman of the meeting shall appoint two inspectors of votes who
shall count all votes cast at the meeting for or against any resolution and who
shall make and file with the secretary of the meeting their verified written
reports in duplicate of all votes cast at the meeting. A record in duplicate of
the proceedings of each meeting of Noteholders shall be prepared by the
secretary of the meeting and there shall be attached to said record the original
reports of the inspectors of votes on any vote by ballot taken thereat and
affidavits by one or more persons having knowledge of the facts setting forth a
copy of the notice of the meeting and showing that said notice was mailed as
provided in Section 10.2. The record shall show the principal amount of the
Notes voting in favor of or against any resolution. The record shall be signed
and verified by the affidavits of the permanent chairman and secretary of the
meeting and one of the duplicates shall be delivered to the Company and the
other to the Trustee to be preserved by the Trustee, the latter to have attached
thereto the ballots voted at the meeting.

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

     Section 10.7 No Delay of Rights by Meeting. Nothing contained in this
                  -----------------------------
Article Ten shall be deemed or construed to authorize or permit, by reason of
any call of a meeting of Noteholders or any rights expressly or impliedly
conferred hereunder to make such call, any hindrance or delay in the exercise of
any right or rights conferred upon or reserved to the Trustee or to the
Noteholders under any of the provisions of this Indenture or of the Notes.



                                 ARTICLE ELEVEN

                             SUPPLEMENTAL INDENTURES

     Section 11.1 Supplemental Indentures Without Consent of Noteholders. The
                  ------------------------------------------------------
Company, when authorized by the resolutions of the Board of Directors, and the
Trustee may, from time to

                                      -56-

<PAGE>

time, and at any time enter into an indenture or indentures supplemental hereto
for one or more of the following purposes:

          (a) to make provision with respect to the conversion rights of the
holders of Notes pursuant to the requirements of Section 15.6 and the redemption
obligations of the Company pursuant to the requirements of Section 3.5(e);

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

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

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

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

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

          (g) to evidence and provide for the acceptance of appointment
hereunder by a successor Trustee with respect to the Notes; or

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

     Upon the written request of the Company, accompanied by a copy of the
resolutions of the Board of Directors certified by its Secretary or Assistant
Secretary authorizing the execution of any supplemental indenture, the Trustee
is hereby authorized to join with the Company in the execution

                                      -57-

<PAGE>

of any such supplemental indenture, to make any further appropriate agreements
and stipulations that may be therein contained and to accept the conveyance,
transfer and assignment of any property thereunder, but the Trustee shall not be
obligated to, but may in its discretion, enter into any supplemental indenture
that affects the Trustee's own rights, duties or immunities under this Indenture
or otherwise.

     Any supplemental indenture authorized by the provisions of this Section
11.1 may be executed by the Company and the Trustee without the consent of the
holders of any of the Notes at the time outstanding, notwithstanding any of the
provisions of Section 11.2.

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

     Section 11.2 Supplemental Indenture with Consent of Noteholders. With the
                  --------------------------------------------------
consent (evidenced as provided in Article Nine) of the holders of not less than
a majority in aggregate principal amount of the Notes at the time outstanding,
the Company, when authorized by the resolutions of the Board of Directors, and
the Trustee may, from time to time and at any time, enter into an indenture or
indentures supplemental hereto for the purpose of adding any provisions to or
changing in any manner or eliminating any of the provisions of this Indenture or
any supplemental indenture or of modifying in any manner the rights of the
holders of the Notes; provided, however, that no such supplemental indenture
shall (i) extend the fixed maturity of any Note, or reduce the rate or extend
the time of payment of interest thereon, or reduce the principal amount thereof
or premium, if any, thereon, or reduce any amount payable on redemption or
repurchase thereof, or impair the right of any Noteholder to institute suit for
the payment thereof, or make the principal thereof or interest or premium, if
any, thereon payable in any coin or currency other than that provided in the
Notes, or modify the provisions of this Indenture with respect to the
subordination of the Notes in a manner adverse to the Noteholders in any
material respect, or change the obligation of the Company to redeem any Note
upon the happening of a Fundamental Change in a manner adverse to the holder of
Notes, or impair the right to convert the Notes subject to the terms set forth
herein, including Section 15.6, or decrease the amount of cash payable to a
holder if the Company elects to convert the Notes into cash in lieu of Common
Stock (other than rights of the Company to revoke or otherwise terminate a Cash
Conversion Notice pursuant to the terms of this Indenture), or reduce the quorum
or voting requirements of this Indenture or change any obligation of the Company
to maintain an office or agency in the places and for the purposes specified in
this Indenture, in each case, without the consent of the holder of each Note so
affected, or (ii) reduce the aforesaid percentage of Notes, the holders of which
are required to consent to any such supplemental indenture, without the consent
of the holders of all Notes then outstanding.

     Upon the written request of the Company, accompanied by a copy of the
resolutions of the Board of Directors certified by its Secretary or Assistant
Secretary and authorizing the execution of any such supplemental indenture, and
upon the filing with the Trustee of evidence of the consent of Noteholders as
aforesaid, the Trustee shall join with the Company in the execution of such
supplemental indenture unless such supplemental indenture affects the Trustee's
own rights, duties

                                      -58-

<PAGE>

or immunities under this Indenture or otherwise, in which case the Trustee may
in its discretion, but shall not be obligated to, enter into such supplemental
indenture.

     It shall not be necessary for the consent of the Noteholders under this
Section 11.2 to approve the particular form of any proposed supplemental
indenture, but it shall be sufficient if such consent shall approve the
substance thereof.

     Section 11.3 Effect of Supplemental Indenture. Any supplemental indenture
                  --------------------------------
executed pursuant to the provisions of this Article Eleven shall comply with the
Trust Indenture Act, as then in effect, provided that this Section 11.3 shall
not require such supplemental indenture or the Trustee to be qualified under the
Trust Indenture Act prior to the time such qualification is in fact required
under the terms of the Trust Indenture Act or the Indenture has been qualified
under the Trust Indenture Act, nor shall it constitute any admission or
acknowledgment by any party to such supplemental indenture that any such
qualification is required prior to the time such qualification is in fact
required under the terms of the Trust Indenture Act or the Indenture has been
qualified under the Trust Indenture Act. Upon the execution of any supplemental
indenture pursuant to the provisions of this Article Eleven, this Indenture
shall be and be deemed to be modified and amended in accordance therewith and
the respective rights, limitation of rights, obligations, duties and immunities
under this Indenture of the Trustee, the Company and the holders of Notes shall
thereafter be determined, exercised and enforced hereunder, subject in all
respects to such modifications and amendments and all the terms and conditions
of any such supplemental indenture shall be and be deemed to be part of the
terms and conditions of this Indenture for any and all purposes.

     Section 11.4 Notation on Notes. Notes authenticated and delivered after the
                  -----------------
execution of any supplemental indenture pursuant to the provisions of this
Article Eleven may bear a notation in form approved by the Trustee as to any
matter provided for in such supplemental indenture. If the Company or the
Trustee shall so determine, new Notes so modified as to conform, in the opinion
of the Trustee and the Board of Directors, to any modification of this Indenture
contained in any such supplemental indenture may, at the Company's expense, be
prepared and executed by the Company, authenticated by the Trustee (or an
authenticating agent duly appointed by the Trustee pursuant to Section 16.11)
and delivered in exchange for the Notes then outstanding, upon surrender of such
Notes then outstanding.

     Section 11.5 Evidence of Compliance of Supplemental Indenture to be
                  ------------------------------------------------------
Furnished to Trustee. Prior to entering into any supplemental indenture, the
--------------------
Trustee may request an Officers' Certificate and an Opinion of Counsel meeting
the requirements set forth in Section 16.5 as conclusive evidence that any
supplemental indenture executed pursuant hereto complies with the requirements
of this Article Eleven.

                                      -59-


<PAGE>

                                 ARTICLE TWELVE

                CONSOLIDATION, MERGER, SALE, CONVEYANCE AND LEASE

     Section 12.1 Company May Consolidate, Etc., on Certain Terms. Subject to
                  -----------------------------------------------
the provisions of Section 12.2, nothing contained in this Indenture or in any of
the Notes shall prevent any consolidation or merger of the Company with or into
any other Person or Persons (whether or not affiliated with the Company), or
successive consolidations or mergers in which the Company or its successor or
successors shall be a party or parties, or shall prevent any sale, conveyance or
lease (or successive sales, conveyances or leases) of all or substantially all
of the property of the Company, to any other Person (whether or not affiliated
with the Company), authorized to acquire and operate the same and that shall be
organized under the laws of the United States of America, any state thereof or
the District of Columbia or any other country, if the merger, consolidation or
other transaction would not impair the rights of the holders of the Notes;
provided, however, that upon any such consolidation, merger, sale, conveyance or
lease, (a) no default or Event of Default shall have occurred and be continuing
immediately following such merger, consolidation or other transaction, and (b)
the due and punctual payment of the principal of and premium, if any, and
interest (including Liquidated Damages, if any) on all of the Notes, according
to their tenor and the due and punctual performance and observance of all of the
covenants and conditions of this Indenture to be performed by the Company, shall
be expressly assumed, by supplemental indenture satisfactory in form to the
Trustee, executed and delivered to the Trustee by the Person (if other than the
Company) formed by such consolidation, or into which the Company shall have been
merged, or by the Person that shall have acquired or leased such property, and
such supplemental indenture shall provide for the applicable conversion rights
set forth in Section 15.6.

     Section 12.2 Successor Corporation to be Substituted. In case of any such
                  ---------------------------------------
consolidation, merger, sale, conveyance or lease and upon the assumption by the
successor Person, by supplemental indenture, executed and delivered to the
Trustee and satisfactory in form to the Trustee, of the due and punctual payment
of the principal of and premium, if any, and interest on all of the Notes and
the due and punctual performance of all of the covenants and conditions of this
Indenture to be performed by the Company, such successor Person shall succeed to
and be substituted for the Company, with the same effect as if it had been named
herein as the party of this first part. Such successor Person thereupon may
cause to be signed, and may issue either in its own name or in the name of
Riverstone Networks, Inc. any or all of the Notes, issuable hereunder that
theretofore shall not have been signed by the Company and delivered to the
Trustee; and, upon the order of such successor Person instead of the Company and
subject to all the terms, conditions and limitations in this Indenture
prescribed, the Trustee shall authenticate and shall deliver, or cause to be
authenticated and delivered, any Notes that previously shall have been signed
and delivered by the officers of the Company to the Trustee for authentication,
and any Notes that such successor Person thereafter shall cause to be signed and
delivered to the Trustee for that purpose. All the Notes so issued shall in all
respects have the same legal rank and benefit under this Indenture as the Notes
theretofore or thereafter issued in accordance with the terms of this Indenture
as though all of such Notes had been issued at the date of the execution hereof.
In the event of any such consolidation, merger, sale, conveyance or lease, the
Person named as the "Company" in the first paragraph of this Indenture or any
successor that shall thereafter have become such in the manner prescribed in
this Article Twelve may be dissolved, wound up and liquidated at any time
thereafter

                                      -60-


<PAGE>

and such Person shall be released from its liabilities as obligor and maker of
the Notes and from its obligations under this Indenture.

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

     Section 12.3 Opinion of Counsel to be Given Trustee. The Trustee shall
                  --------------------------------------
receive an Officers' Certificate and an Opinion of Counsel as conclusive
evidence that any such consolidation, merger, sale, conveyance or lease and any
such assumption complies with the provisions of this Article Twelve.



                                ARTICLE THIRTEEN

                     SATISFACTION AND DISCHARGE OF INDENTURE

     Section 13.1 Discharge of Indenture. When (a) the Company shall deliver to
                  ----------------------
the Trustee for cancellation all Notes theretofore authenticated (other than any
Notes that have been destroyed, lost or stolen and in lieu of or in substitution
for which other Notes shall have been authenticated and delivered) and not
theretofore canceled, or (b) all the Notes not theretofore canceled or delivered
to the Trustee for cancellation shall have become due and payable, or are by
their terms to become due and payable within one year or are to be called for
redemption within one year under arrangements satisfactory to the Trustee for
the giving of notice of redemption, and the Company shall deposit with the
Trustee, in trust, funds sufficient to pay at maturity or upon redemption of all
of the Notes (other than any Notes that shall have been mutilated, destroyed,
lost or stolen and in lieu of or in substitution for which other Notes shall
have been authenticated and delivered) not theretofore canceled or delivered to
the Trustee for cancellation, including principal and premium, if any, and
interest due or to become due to such date of maturity or redemption date, as
the case may be, accompanied by a verification report, as to the sufficiency of
the deposited amount, from an independent certified accountant or other
financial professional satisfactory to the Trustee, and if the Company shall
also pay or cause to be paid all other sums payable hereunder by the Company,
then this Indenture shall cease to be of further effect (except as to (i)
remaining rights of registration of transfer, substitution and exchange and
conversion of Notes, (ii) rights hereunder of Noteholders to receive payments of
principal of and premium, if any, and interest on, the Notes and the other
rights, duties and obligations of Noteholders, as beneficiaries hereof with
respect to the amounts, if any, so deposited with the Trustee and (iii) the
rights, obligations and immunities of the Trustee hereunder), and the Trustee,
on written demand of the Company accompanied by an Officers' Certificate and an
Opinion of Counsel as required by Section 16.5 and at the cost and expense of
the Company, shall execute proper instruments acknowledging satisfaction of and
discharging this Indenture; the Company, however, hereby agrees to reimburse the
Trustee for any costs or expenses thereafter reasonably and properly incurred by
the Trustee and to compensate the Trustee for any services thereafter reasonably
and properly rendered by the Trustee in connection with this Indenture or the
Notes.

                                      -61-


<PAGE>

     Section 13.2 Deposited Monies to be Held in Trust by Trustee. Subject to
                  -----------------------------------------------
Section 13.4, all monies deposited with the Trustee pursuant to Section 13.1,
provided such deposit was not in violation of Article Four, shall be held in
trust for the sole benefit of the Noteholders and not to be subject to the
subordination provisions of Article Four, and such monies shall be applied by
the Trustee to the payment, either directly or through any paying agent
(including the Company if acting as its own paying agent), to the holders of the
particular Notes for the payment or redemption of which such monies have been
deposited with the Trustee, of all sums due and to become due thereon for
principal and interest and premium, if any.

     Section 13.3 Paying Agent to Repay Monies Held. Upon the satisfaction and
                  ---------------------------------
discharge of this Indenture, all monies then held by any paying agent of the
Notes (other than the Trustee) shall, upon written request of the Company, be
repaid to it or paid to the Trustee, and thereupon such paying agent shall be
released from all further liability with respect to such monies.

     Section 13.4 Return of Unclaimed Monies. Subject to the requirements of
                  --------------------------
applicable law, any monies deposited with or paid to the Trustee for payment of
the principal of, premium, if any, or interest on Notes and not applied but
remaining unclaimed by the holders of Notes for two years after the date upon
which the principal of, premium, if any, or interest on such Notes, as the case
may be, shall have become due and payable, shall be repaid to the Company by the
Trustee on demand and all liability of the Trustee shall thereupon cease with
respect to such monies; and the holder of any of the Notes shall thereafter look
only to the Company for any payment that such holder may be entitled to collect
unless an applicable abandoned property law designates another Person.

     Section 13.5 Reinstatement. If the Trustee or the paying agent is unable to
                  -------------
apply any money in accordance with Section 13.2 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 13.1 until such time as the Trustee or the paying
agent is permitted to apply all such money in accordance with Section 13.2;
provided, however, that if the Company makes any payment of interest on or
principal of any Note following 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 held by the Trustee or paying agent.



                                ARTICLE FOURTEEN

                           IMMUNITY OF INCORPORATORS,
                      STOCKHOLDERS, OFFICERS AND DIRECTORS

     Section 14.1 Indenture and Notes Solely Corporate Obligations. No recourse
                  ------------------------------------------------
for the payment of the principal of or premium, if any, or interest on any Note,
or for any claim based thereon or otherwise in respect thereof, and no recourse
under or upon any obligation, covenant or agreement of the Company in this
Indenture or in any supplemental indenture or in any Note, or because of the
creation of any indebtedness represented thereby, shall be had against any
incorporator, stockholder, employee, agent, officer, director or subsidiary, as
such, past, present or

                                      -62-

<PAGE>

future, of the Company or of any successor corporation, either directly or
through the Company or any successor corporation, whether by virtue of any
constitution, statute or rule of law, or by the enforcement of any assessment or
penalty or otherwise; it being expressly understood that all such liability is
hereby expressly waived and released as a condition of, and as a consideration
for, the execution of this Indenture and the issue of the Notes.



                                ARTICLE FIFTEEN

                              CONVERSION OF NOTES

     Section 15.1 Right to Convert. Subject to and upon compliance with the
                  ----------------
provisions of this Indenture, including, without limitation, Article Four, the
holder of any Note shall have the right, at its option, at any time after the
original issuance of the Notes hereunder through the close of business on the
final maturity date of the Notes (except that, with respect to any Note or
portion of a Note that shall be called for redemption, such right shall
terminate, except as provided in Section 15.2, Section 3.2 or Section 3.4, at
the close of business on the Business Day next preceding the date fixed for
redemption of such Note or portion of a Note unless the Company shall default in
payment due upon redemption thereof) to convert the principal amount of any such
Note, or any portion of such principal amount which is $1,000 or an integral
multiple thereof. The Notes will be convertible at the Conversion Rate,
determined as hereinafter provided, in effect at the time of conversion into
fully paid and non-assessable shares of Common Stock of the Company (as such
shares shall then be constituted), by surrender of the Note so to be converted
in whole or in part in the manner provided, together with any required funds, in
Section 15.2. Notwithstanding the foregoing, in lieu of issuing shares of the
Company's Common Stock upon conversion, the Company may elect to pay cash, but
only with 30 days' prior written notice to all holders of Notes. If the Company
elects to convert the Notes into cash, it will pay the holder of the Notes an
amount equal to 105% of the value of the Common Stock the holder would have
received had the Notes been converted into shares of the Company's Common Stock.
For this purpose, the value of the Common Stock will be based on the last
reported sale price for the Company's Common Stock on the date of conversion
unless shares of such Common Stock are not approved for quotation on the Nasdaq
National Market or any similar United States system of automated dissemination
of quotations of securities prices, in which case such value will be based on
the good faith estimate of the Company's Board of Directors.

     A Note in respect of which a holder is exercising its option to require
redemption upon a Fundamental Change pursuant to Section 3.5 may be converted
only if such holder withdraws its election to exercise in accordance with
Section 3.5. A holder of Notes is not entitled to any rights of a holder of
Common Stock until such holder has converted his Notes to Common Stock, and only
to the extent such Notes are deemed to have been converted to Common Stock under
this Article Fifteen.

     Section 15.2 Exercise of Conversion Privilege; Issuance of Common Stock or
                  -------------------------------------------------------------
Cash on Conversion; No Adjustment for Interest or Dividends. In order to
-----------------------------------------------------------
exercise the conversion privilege with respect to any Note in certificated form,
the holder of any such Note to be converted in whole or in part shall surrender
such Note, duly endorsed, at an office or agency maintained by the

                                      -63-

<PAGE>

Company pursuant to Section 5.2, accompanied by the funds, if any, required by
the penultimate paragraph of this Section 15.2, and shall give written notice of
conversion in the form provided on the Notes (or such other notice which is
acceptable to the Company) to the office or agency that the holder elects to
convert such Note or the portion thereof specified in said notice. If the Notes
are converted into Common Stock, such notice shall also state the name or names
(with address or addresses) in which the certificate or certificates for shares
of Common Stock which shall be issuable on such conversion shall be issued, and
shall be accompanied by transfer taxes, if required pursuant to Section 15.7.
Each such Note surrendered for conversion into Common Stock shall, unless the
shares issuable on conversion are to be issued in the same name as the
registration of such Note, be duly endorsed by, or be accompanied by instruments
of transfer in form satisfactory to the Company duly executed by, the holder or
his duly authorized attorney. The notice shall also contain an acknowledgement
that if the Company has previously provided notice of its election to make a
cash payment in lieu of issuing shares upon conversion and such notice is
effective and has not been revoked or terminated, the Company shall make a cash
payment to the registered owner of the Note equal to 105% of the value of the
Common Stock that such registered owner would have received upon conversion of
the Notes.

     In order to convert the Notes into cash, the Company must have previously
provided to the holder of the Notes and the Trustee 30 days' prior written
notice of its election to make such cash conversion (the "Cash Conversion
Notice"). Any such notice shall apply to conversions after the effective time of
such notice and until such notice terminates or is revoked. The Company may
revoke any such notice and, with 30 days' prior written notice, the Company may
reinstate any revoked notice. The Company will only pay cash in lieu of issuing
Common Stock upon conversion of any Notes called for redemption by the Company
if the notice of redemption specifies the Company's intention to pay cash upon
conversion. If the notice of redemption fails to specify that the Company
intends to make a cash payment in lieu of issuing shares of Common Stock upon
conversion of the Notes, the Company must convert the Notes into shares of its
Common Stock. Additionally, if under either the Rights Agreement or a New Rights
Plan, the rights have separated from the Common Stock at the time of conversion,
the Company's right to convert the Notes into cash in lieu of shares of Common
Stock pursuant to Section 15.1 will be terminated and any pending Cash
Conversion Notice will be deemed revoked.

     Any cash payment made in settlement of conversion will be made on the
second Business Day following the Conversion Date. If the Company fails to make
the cash payment on the second Business Day following the Conversion Date, the
holder hereof has the right to elect to receive shares of Common Stock in lieu
of such payment. If the Company elects to convert the Notes into cash, on or
prior to the second Business Day following the Conversion Date, the Company
shall deposit with the Trustee or with one or more paying agents (or, if the
Company is acting as its own paying agent, set aside, segregate and hold in
trust as provided in Section 5.4) an amount of money sufficient to pay the total
amount due on the conversion all the Notes to be converted into cash on such
date, together with accrued interest to be paid pursuant to Section 2.3;
provided, however, that if such payment is made on the second Business Day
following the Conversion Date it must be received by the Trustee or paying
agent, as the case may be, by 10:00 a.m. New York City time, on such date.

                                      -64-


<PAGE>

     In order to exercise the conversion privilege with respect to any interest
in a Note in global form, the beneficial holder must complete, or cause to be
completed, the appropriate instruction form for conversion pursuant to the
Depository's book-entry conversion program, deliver, or cause to be delivered,
by book-entry delivery an interest in such Note in global form, furnish
appropriate endorsements and transfer documents if required by the Company or
the Trustee or conversion agent, and pay the funds, if any, required by this
Section 15.2 and any transfer taxes if required pursuant to Section 15.7.

     As promptly as practicable after satisfaction of the requirements for
conversion into Common Stock set forth above, subject to compliance with any
restrictions on transfer if shares issuable on conversion are to be issued in a
name other than that of the Noteholder (as if such transfer were a transfer of
the Note or Notes (or portion thereof) so converted), the Company shall issue
and shall deliver to such Noteholder at the office or agency maintained by the
Company for such purpose pursuant to Section 5.2, a certificate or certificates
for the number of full shares of Common Stock issuable upon the conversion of
such Note or portion thereof as determined by the Company in accordance with the
provisions of this Article Fifteen and a check or cash in respect of any
fractional interest in respect of a share of Common Stock arising upon such
conversion, calculated by the Company as provided in Section 15.3. In case any
Note of a denomination greater than $1,000 shall be surrendered for partial
conversion, and subject to Section 2.3, the Company shall execute and the
Trustee shall authenticate and deliver to the holder of the Note so surrendered,
without charge to him, a new Note or Notes in authorized denominations in an
aggregate principal amount equal to the unconverted portion of the surrendered
Note.

     Each conversion shall be deemed to have been effected as to any such Note
(or portion thereof) on the date on which the requirements of the holder set
forth above in this Section 15.2 have been satisfied as to such Note (or portion
thereof) (a "Conversion Date"). The Person in whose name any certificate or
certificates for shares of Common Stock shall be issuable upon such conversion
shall be deemed to have become on said date the holder of record of the shares
represented thereby; provided, however, that any such surrender on any date when
the stock transfer books of the Company shall be closed shall constitute the
Person in whose name the certificates are to be issued as the record holder
thereof for all purposes on the next succeeding day on which such stock transfer
books are open, but such conversion shall be at the Conversion Rate in effect on
the date upon which such Note shall be surrendered.

     No adjustment in respect of interest on any Note converted or dividends on
any shares issued upon conversion of such Note will be made upon any conversion
except as set forth in the next sentence. If this Note (or portion hereof) is
surrendered for conversion during the period from the close of business on any
record date for the payment of interest to the close of business on the Business
Day preceding the following interest payment date and either (x) has not been
called for redemption on a redemption date that occurs during such period or (y)
is not to be redeemed in connection with a Fundamental Change on a Repurchase
Date that occurs during such period, this Note (or portion hereof being
converted) must be accompanied by an amount, in New York Clearing House funds or
other funds acceptable to the Company, equal to the interest payable on such
interest payment date on the principal amount being converted; provided,
however, that no such payment

                                      -65-

<PAGE>

shall be required if there shall exist at the time of conversion a default in
the payment of interest on the Notes.

     Upon the conversion of an interest in a Note in global form, the Trustee
(or other conversion agent appointed by the Company), or the Custodian at the
direction of the Trustee (or other conversion agent appointed by the Company),
shall make a notation on such Note in global form as to the reduction in the
principal amount represented thereby. The Company shall notify the Trustee in
writing of any conversions of Notes effected through any conversion agent other
than the Trustee.

     Section 15.3 Cash Payments in Lieu of Fractional Shares. No fractional
                  ------------------------------------------
shares of Common Stock or scrip representing fractional shares shall be issued
upon conversion of Notes. If more than one Note shall be surrendered for
conversion at one time by the same holder, the number of full shares that shall
be issuable upon conversion shall be computed on the basis of the aggregate
principal amount of the Notes (or specified portions thereof to the extent
permitted thereby) so surrendered. If any fractional share of stock would be
issuable upon the conversion of any Note or Notes, the Company shall make an
adjustment and payment therefor in cash at the current market price thereof to
the holder of Notes. The current market price of a share of Common Stock for
purposes of this Section 15.3 shall be the Closing Price on the last Business
Day immediately preceding the Conversion Date.

     Section 15.4 Conversion Price. The conversion rate shall be as specified in
                  ----------------
the form of Note (herein called the "Conversion Rate") attached as Exhibit A
hereto, subject to adjustment as provided in this Article Fifteen.

     Section 15.5 Adjustment of Conversion Rate. The Conversion Rate shall be
                  -----------------------------
adjusted from time to time by the Company as follows:

          (a) In case the Company shall hereafter pay a dividend or make a
distribution to all holders of the outstanding Common Stock in shares of Common
Stock, the Conversion Rate shall be increased so that the same shall equal the
rate determined by multiplying the Conversion Rate in effect at the opening of
business on the date following the date fixed for the determination of
stockholders entitled to receive such dividend or other distribution by a
fraction, the numerator of which shall be the sum of the number of shares of the
Common Stock outstanding at the close of business on the date fixed for such
determination and the total number of shares constituting such dividend or other
distribution, and the denominator of which shall be the number of shares of the
Common Stock outstanding at the close of business on the date fixed for such
determination, such increase to become effective immediately after the opening
of business on the day following the date fixed for such determination. For the
purpose of this paragraph (a), the number of shares of Common Stock at any time
outstanding shall not include shares held in the treasury of the Company. The
Company will not pay any dividend or make any distribution on shares of Common
Stock held in the treasury of the Company. If any dividend or distribution of
the type described in this Section 15.5(a) is declared but not so paid or made,
the Conversion Rate shall again be adjusted to the Conversion Rate that would
then be in effect if such dividend or distribution had not been declared.

                                      -66-


<PAGE>

          (b) In case the Company shall issue rights or warrants to all holders
of its outstanding shares of Common Stock entitling them (for a period expiring
within forty-five (45) days after the date fixed for determination of
stockholders entitled to receive such rights or warrants) to subscribe for or
purchase shares of Common Stock at a price per share less than the Current
Market Price (as defined below) on the date fixed for determination of
stockholders entitled to receive such rights or warrants, the Conversion Rate
shall be adjusted so that the same shall equal the rate determined by
multiplying the Conversion Rate in effect immediately prior to the date fixed
for determination of stockholders entitled to receive such rights or warrants by
a fraction, the numerator of which shall be the number of shares of Common Stock
outstanding on the date fixed for determination of stockholders entitled to
receive such rights or warrants plus the total number of additional shares of
Common Stock offered for subscription or purchase and the denominator of which
shall be the number of shares of Common Stock outstanding at the close of
business on the date fixed for determination of stockholders entitled to receive
such rights or warrants plus the number of shares that the aggregate offering
price of the total number of shares so offered would purchase at such Current
Market Price. Such adjustment shall be successively made whenever any such
rights or warrants are issued, and shall become effective immediately after the
opening of business on the day following the date fixed for determination of
stockholders entitled to receive such rights or warrants. To the extent that
shares of Common Stock are not delivered after the expiration of such rights or
warrants, the Conversion Rate shall be readjusted to the Conversion Rate that
would then be in effect had the adjustments made upon the issuance of such
rights or warrants been made on the basis of delivery of only the number of
shares of Common Stock actually delivered. In the event that such rights or
warrants are not so issued, the Conversion Rate shall again be adjusted to be
the Conversion Rate that would then be in effect if such date fixed for the
determination of stockholders entitled to receive such rights or warrants had
not been fixed. In determining whether any rights or warrants entitle the
holders to subscribe for or purchase shares of Common Stock at less than such
Current Market Price, and in determining the aggregate offering price of such
shares of Common Stock, there shall be taken into account any consideration
received by the Company for such rights or warrants and any amount payable on
exercise or conversion thereof, the value of such consideration, if other than
cash, to be determined by the Board of Directors.

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

          (d) In case the Company shall, by dividend or otherwise, distribute to
all holders of its Common Stock shares of any class of capital stock of the
Company (other than any dividends or distributions to which Section 15.5(a)
applies) or evidences of its indebtedness or assets (including securities, but
excluding any rights or warrants referred to in Section 15.5(b), and excluding
any

                                      -67-

<PAGE>

dividend or distribution (x) paid exclusively in cash or (y) referred to in
Section 15.5(a) (any of the foregoing hereinafter in this Section 15.5(d) called
the "Securities")), then, in each such case (unless the Company elects to
reserve such Securities for distribution to the Noteholders upon the conversion
of the Notes so that any such holder converting Notes will receive upon such
conversion, in addition to the shares of Common Stock to which such holder is
entitled, the amount and kind of such Securities which such holder would have
received if such holder had converted its Notes into Common Stock immediately
prior to the Record Date (as defined in Section 15.5(h)(4) for such distribution
of the Securities)), the Conversion Rate shall be increased so that the same
shall be equal to the rate determined by multiplying the Conversion Rate in
effect on the Record Date with respect to such distribution by a fraction, the
numerator of which shall be the Current Market Price per share of the Common
Stock and the denominator of which shall be the Current Market Price per share
of the Common Stock on such Record Date less the fair market value (as
determined by the Board of Directors, whose determination shall be conclusive,
and described in a resolution of the Board of Directors) on the Record Date of
the portion of the Securities so distributed applicable to one share of Common
Stock, such increase to become effective immediately prior to the opening of
business on the day following such Record Date; provided, however, that in the
event the then fair market value (as so determined) of the portion of the
Securities so distributed applicable to one share of Common Stock is equal to or
greater than the Current Market Price of the Common Stock on the Record Date, in
lieu of the foregoing adjustment, adequate provision shall be made so that each
Noteholder shall have the right to receive upon conversion the amount of
Securities such holder would have received had such holder converted each Note
on the Record Date. In the event that such dividend or distribution is not so
paid or made, the Conversion Rate shall again be adjusted to be the Conversion
Rate that would then be in effect if such dividend or distribution had not been
declared. If the Board of Directors determines the fair market value of any
distribution for purposes of this Section 15.5(d) by reference to the actual or
when issued trading market for any securities, it must in doing so consider the
prices in such market over the same period used in computing the Current Market
Price of the Common Stock.

     Under the provisions of the Company's Rights Agreement with Mellon Investor
Services, L.L.C., as Rights Agent, dated as of July 16, 2001 (the "Rights
Agreement"), upon conversion of the Notes into Common Stock, to the extent that
the Rights Agreement is still in effect upon such conversion, the holders of
Notes will receive, in addition to the Common Stock, the rights described
therein (whether or not the rights have separated from the Common Stock at the
time of conversion), subject to the limitations set forth in the Rights
Agreement. In addition, if the Company implements a new rights plan ("New Rights
Plan"), the Company will provide under such New Rights Plan that the holders of
the Notes will receive, in addition to the Common Stock, the rights under the
New Rights Plan (whether or not the rights under the New Rights Plan have
separated from the Common Stock at the time of conversion), subject to any
limitations set forth in the New Rights Plan. Notwithstanding the foregoing,
nothing in this Indenture shall obligate the Company to maintain in effect the
Rights Agreement or any rights thereunder, or to adopt (or maintain in effect if
adopted) any New Rights Plan.

     Rights or warrants distributed by the Company to all holders of Common
Stock entitling the holders thereof to subscribe for or purchase shares of the
Company's capital stock (either initially or

                                      -68-

<PAGE>

under certain circumstances) other than pursuant to the Company's Rights
Agreement or any New Rights Plan, which rights or warrants, until the occurrence
of a specified event or events ("Trigger Event"): (i) are deemed to be
transferred with such shares of Common Stock; (ii) are not exercisable; and
(iii) are also issued in respect of future issuances of Common Stock, shall be
deemed not to have been distributed for purposes of this Section 15.5 (and no
adjustment to the Conversion Rate under this Section 15.5 will be required)
until the occurrence of the earliest Trigger Event, whereupon such rights and
warrants shall be deemed to have been distributed and an appropriate adjustment
(if any is required) to the Conversion Rate shall be made under this Section
15.5(d). If any such right or warrant, including any such existing rights or
warrants distributed prior to the date of this Indenture, are subject to events,
upon the occurrence of which such rights or warrants become exercisable to
purchase different securities, evidences of indebtedness or other assets, then
the date of the occurrence of any and each such event shall be deemed to be the
date of distribution and record date with respect to new rights or warrants with
such rights (and a termination or expiration of the existing rights or warrants
without exercise by any of the holders thereof). In addition, in the event of
any distribution (or deemed distribution) of rights or warrants, or any Trigger
Event or other event (of the type described in the preceding sentence) with
respect thereto that was counted for purposes of calculating a distribution
amount for which an adjustment to the Conversion Rate under this Section 15.5
was made, (1) in the case of any such rights or warrants that shall all have
been redeemed or repurchased without exercise by any holders thereof, the
Conversion Rate shall be readjusted upon such final redemption or repurchase to
give effect to such distribution or Trigger Event, as the case may be, as though
it were a cash distribution, equal to the per share redemption or repurchase
price received by a holder or holders of Common Stock with respect to such
rights or warrants (assuming such holder had retained such rights or warrants),
made to all holders of Common Stock as of the date of such redemption or
repurchase, and (2) in the case of such rights or warrants that shall have
expired or been terminated without exercise by any holders thereof, the
Conversion Rate shall be readjusted as if such rights and warrants had not been
issued.

     No adjustment of the Conversion Rate shall be made pursuant to this Section
15.5(d) in respect of rights or warrants distributed or deemed distributed on
any Trigger Event to the extent that such rights or warrants are actually
distributed, or reserved by the Company for distribution to holders of Notes
upon conversion by such holders of Notes to Common Stock.

     For purposes of this Section 15.5(d) and Sections 15.5(a) and (b), any
dividend or distribution to which this Section 15.5(d) is applicable that also
includes shares of Common Stock, or rights or warrants to subscribe for or
purchase shares of Common Stock (or both), shall be deemed instead to be (1) a
dividend or distribution of the evidences of indebtedness, assets or shares of
capital stock other than such shares of Common Stock or rights or warrants (and
any Conversion Rate increase required by this Section 15.5(d) with respect to
such dividend or distribution shall then be made) immediately followed by (2) a
dividend or distribution of such shares of Common Stock or such rights or
warrants (and any further Conversion Rate increase required by Sections 15.5(a)
and (b) with respect to such dividend or distribution shall then be made),
except (A) the Record Date of such dividend or distribution shall be substituted
as "the date fixed for the determination of stockholders entitled to receive
such dividend or other distribution", "the date fixed for the determination of
stockholders entitled to receive such rights or warrants" and "the date fixed
for

                                      -69-

<PAGE>

such determination" within the meaning of Sections 15.5(a) and (b), and (B) any
shares of Common Stock included in such dividend or distribution shall not be
deemed "outstanding at the close of business on the date fixed for such
determination" within the meaning of Section 15.5(a).

          (e) In case the Company shall, by dividend or otherwise, distribute to
all holders of its Common Stock cash (excluding (x) any quarterly cash dividend
on the Common Stock to the extent the aggregate cash dividend per share of
Common Stock in any fiscal quarter does not exceed the greater of (A) the amount
per share of Common Stock of the next preceding quarterly cash dividend on the
Common Stock to the extent that such preceding quarterly dividend did not
require any adjustment of the Conversion Rate pursuant to this Section 15.5(e)
(as adjusted to reflect subdivisions, or combinations of the Common Stock), and
(B) 3 3/4% of the arithmetic average of the Closing Price (determined as set
forth in Section 15.5(h)) during the ten Trading Days (as defined in Section
15.5(h)) immediately prior to the date of declaration of such dividend, and (y)
any dividend or distribution in connection with the liquidation, dissolution or
winding up of the Company, whether voluntary or involuntary), then, in such
case, the Conversion Rate shall be increased so that the same shall equal the
rate determined by multiplying the Conversion Rate in effect immediately prior
to the close of business on such record date by a fraction, the numerator of
which shall be such Current Market Price of the Common Stock and the denominator
of which shall be the Current Market Price of the Common Stock on the record
date less the amount of cash so distributed (and not excluded as provided above)
applicable to one share of Common Stock, such increase to be effective
immediately prior to the opening of business on the day following the record
date; provided, however, that in the event the portion of the cash so
distributed applicable to one share of Common Stock is equal to or greater than
the Current Market Price of the Common Stock on the record date, in lieu of the
foregoing adjustment, adequate provision shall be made so that each Noteholder
shall have the right to receive upon conversion the amount of cash such holder
would have received had such holder converted each Note on the record date. In
the event that such dividend or distribution is not so paid or made, the
Conversion Rate shall again be adjusted to be the Conversion Rate that would
then be in effect if such dividend or distribution had not been declared. If any
adjustment is required to be made as set forth in this Section 15.5(e) as a
result of a distribution that is a quarterly dividend, such adjustment shall be
based upon the amount by which such distribution exceeds the amount of the
quarterly cash dividend permitted to be excluded pursuant hereto. If an
adjustment is required to be made as set forth in this Section 15.5(e) above as
a result of a distribution that is not a quarterly dividend, such adjustment
shall be based upon the full amount of the distribution.

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

                                      -70-

<PAGE>

market value (determined as aforesaid) of the aggregate consideration payable to
stockholders based on the acceptance (up to any maximum specified in the terms
of the tender or exchange offer) of all shares validly tendered or exchanged and
not withdrawn as of the Expiration Time (the shares deemed so accepted, up to
any such maximum, being referred to as the "Purchased Shares") and (y) the
product of the number of shares of Common Stock outstanding (less any Purchased
Shares) at the Expiration Time and the Current Market Price of the Common Stock
on the Trading Day next succeeding the Expiration Time and the denominator of
which shall be the number of shares of Common Stock outstanding (including any
tendered or exchanged shares) at the Expiration Time multiplied by the Current
Market Price of the Common Stock on the Trading Day next succeeding the
Expiration Time, such increase to become effective immediately prior to the
opening of business on the Trading Day following the Expiration Time. In the
event that the Company is obligated to purchase shares pursuant to any such
tender or exchange offer, but the Company is permanently prevented by applicable
law from effecting any such purchases or all such purchases are rescinded, the
Conversion Rate shall again be adjusted to be the Conversion Rate that would
then be in effect if such tender or exchange offer had not been made.

          (g) In case of a tender or exchange offer made by a Person other than
the Company or any Subsidiary for an amount that increases the offeror's
ownership of Common Stock to more than twenty-five percent (25%) of the Common
Stock outstanding and shall involve the payment by such Person of consideration
per share of Common Stock having a fair market value (as determined by the Board
of Directors, whose determination shall be conclusive, and described in a
resolution of the Board of Directors) that as of the last time (the "Offer
Expiration Time") tenders or exchanges may be made pursuant to such tender or
exchange offer (as it shall have been amended) that exceeds the Current Market
Price of the Common Stock on the Trading Day next succeeding the Offer
Expiration Time, and in which, as of the Offer Expiration Time the Board of
Directors is not recommending rejection of the offer, the Conversion Rate shall
be increased so that the same shall equal the rate determined by multiplying the
Conversion Rate in effect immediately prior to the Offer Expiration Time by a
fraction the numerator of which shall be the sum of (x) the fair market value
(determined as aforesaid) of the aggregate consideration payable to stockholders
based on the acceptance (up to any maximum specified in the terms of the tender
or exchange offer) of all shares validly tendered or exchanged and not withdrawn
as of the Offer Expiration Time (the shares deemed so accepted, up to any such
maximum, being referred to as the "Accepted Purchased Shares") and (y) the
product of the number of shares of Common Stock outstanding (less any Accepted
Purchased Shares) at the Offer Expiration Time and the Current Market Price of
the Common Stock on the Trading Day next succeeding the Offer Expiration Time
and the denominator of which shall be the number of shares of Common Stock
outstanding (including any tendered or exchanged shares) at the Offer Expiration
Time multiplied by the Current Market Price of the Common Stock on the Trading
Day next succeeding the Offer Expiration Time, such increase to become effective
immediately prior to the opening of business on the Trading Day following the
Offer Expiration Time. In the event that such Person is obligated to purchase
shares pursuant to any such tender or exchange offer, but such Person is
permanently prevented by applicable law from effecting any such purchases or all
such purchases are rescinded, the Conversion Rate shall again be adjusted to be
the Conversion Rate that would then be in effect if such tender or exchange
offer had not been made. Notwithstanding the foregoing, the adjustment described
in this Section 15.5(g)

                                      -71-

<PAGE>

shall not be made if, as of the Offer Expiration Time, the offering documents
with respect to such offer disclose a plan or intention to cause the Company to
engage in any transaction described in Article Twelve.

          (h) For purposes of this Section 15.5, the following terms shall have
the meaning indicated:

               (1) "Closing Price" with respect to any security on any day shall
          mean the closing sale price, regular way, on such day or, in case no
          such sale takes place on such day, the average of the reported closing
          bid and asked prices, regular way, in each case as quoted on the
          Nasdaq National Market or, if such security is not quoted or listed or
          admitted to trading on such Nasdaq National Market, on the principal
          national securities exchange or quotation system on which such
          security is quoted or listed or admitted to trading or, if not quoted
          or listed or admitted to trading on any national securities exchange
          or quotation system, the average of the closing bid and asked prices
          of such security on the over-the-counter market on the day in question
          as reported by the National Quotation Bureau Incorporated, or a
          similar generally accepted reporting service, or if not so available,
          in such manner as furnished by any New York Stock Exchange member firm
          selected from time to time by the Board of Directors for that purpose,
          or a price determined in good faith by the Board of Directors or, to
          the extent permitted by applicable law, a duly authorized committee
          thereof, whose determination shall be conclusive.

               (2) "Current Market Price" shall mean the average of the daily
          Closing Prices per share of Common Stock for the ten consecutive
          Trading Days immediately prior to the date in question except as
          hereinafter provided for purposes of any computation under Section
          15.5(f) or (g); provided, however, that (1) if the "ex" date (as
          hereinafter defined) for any event (other than the issuance or
          distribution requiring such computation and other than the tender or
          exchange offer requiring such computation under Section 15.5(f) or
          (g)) that requires an adjustment to the Conversion Rate pursuant to
          Section 15.5(a), (b), (c), (d), (e), (f) or (g) occurs during such ten
          consecutive Trading Days, the Closing Price for each Trading Day prior
          to the "ex" date for such other event shall be adjusted by dividing
          such Closing Price by the same fraction by which the Conversion Rate
          is so required to be adjusted as a result of such other event, (2) if
          the "ex" date for any event (other than the issuance or distribution
          requiring such computation and other than the tender or exchange offer
          requiring such computation under Section 15.5(f) or (g)) that requires
          an adjustment to the Conversion Rate pursuant to Section 15.5(a), (b),
          (c), (d), (e), (f) or (g) occurs on or after the "ex" date for the
          issuance or distribution requiring such computation and prior to the
          day in question, the Closing Price for each Trading Day on and after
          the "ex" date for such other event shall be adjusted by dividing such
          Closing Price by the reciprocal of the fraction by which the
          Conversion Rate is so required to be adjusted as a result of such
          other event, and (3) if the "ex" date for the issuance or distribution
          requiring such computation is prior to the day in question, after
          taking

                                      -72-

<PAGE>

          into account any adjustment required pursuant to clause (1) or (2) of
          this proviso, the Closing Price for each Trading Day on or after such
          "ex" date shall be adjusted by adding thereto the amount of any cash
          and the fair market value (as determined by the Board of Directors or,
          to the extent permitted by applicable law, a duly authorized committee
          thereof in a manner consistent with any determination of such value
          for purposes of Section 15.5(d), (f) or (g), whose determination shall
          be conclusive and described in a resolution of the Board of Directors
          or such duly authorized committee thereof, as the case may be) of the
          evidences of indebtedness, shares of capital stock or assets being
          distributed applicable to one share of Common Stock as of the close of
          business on the day before such "ex" date. For purposes of any
          computation under Section 15.5(f) or (g), the "Current Market Price"
          of the Common Stock on any date shall be deemed to be the average of
          the daily Closing Prices per share of Common Stock for such day and
          the next two succeeding Trading Days; provided, however, that if the
          "ex" date for any event (other than the tender or exchange offer
          requiring such computation under Section 15.5(f) or (g)) that requires
          an adjustment to the Conversion Rate pursuant to Section 15.5(a), (b),
          (c), (d), (e), (f) or (g) occurs on or after the Expiration Time or
          Offer Expiration Time, as the case may be, for the tender or exchange
          offer requiring such computation and prior to the day in question, the
          Closing Price for each Trading Day on and after the "ex" date for such
          other event shall be adjusted as provided in clauses (1), (2) and (3)
          of the proviso contained in the first sentence of this Section
          15.5(h)(2). For purpose of this paragraph, the term "ex" date, (1)
          when used with respect to any issuance or distribution, means the
          first date on which the Common Stock trades, regular way, on the
          relevant exchange or in the relevant market from which the Closing
          Price was obtained without the right to receive such issuance or
          distribution, (2) when used with respect to any subdivision or
          combination of shares of Common Stock, means the first date on which
          the Common Stock trades, regular way, on such exchange or in such
          market after the time at which such subdivision or combination becomes
          effective, and (3) when used with respect to any tender or exchange
          offer means the first date on which the Common Stock trades, regular
          way, on such exchange or in such market after the Expiration Time or
          the Offer Expiration Time of such offer.

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

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

                                      -73-


<PAGE>

               (5) "Trading Day" shall mean (x) if the applicable security is
          quoted on the Nasdaq National Market, a day on which trades may be
          made thereon or (y) if the applicable security is listed or admitted
          for trading on the New York Stock Exchange or another national
          securities exchange, a day on which the New York Stock Exchange or
          another national securities exchange is open for business or (z) if
          the applicable security is not so listed, admitted for trading or
          quoted, any day other than a Saturday or Sunday or a day on which
          banking institutions in the State of New York are authorized or
          obligated by law or executive order to close.

          (i) The Company may make such increases in the Conversion Rate, in
addition to those required by Sections 15.5(a), (b), (c), (d), (e), (f) or (g)
as the Board of Directors considers to be advisable to avoid or diminish any
income tax to holders of Common Stock or rights to purchase Common Stock
resulting from any dividend or distribution of stock (or rights to acquire
stock) or from any event treated as such for income tax purposes.

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

          (j) No adjustment in the Conversion Rate shall be required unless such
adjustment would require an increase or decrease of at least one percent (1%) in
such ratio; provided, however, that any adjustments that by reason of this
Section 15.5(j) are not required to be made shall be carried forward and taken
into account in any subsequent adjustment. No adjustment need be made for rights
to purchase Common Stock pursuant to a Company plan for reinvestment of
dividends or interest. To the extent the Notes become convertible into cash,
assets, property or securities (other than capital stock of the Company), no
adjustment need be made thereafter as to the cash, assets, property or such
securities. Interest will not accrue on the cash.

          (k) Whenever the Conversion Rate is adjusted as herein provided, the
Company shall promptly file with the Trustee and any conversion agent other than
the Trustee an Officers' Certificate setting forth the Conversion Rate after
such adjustment and setting forth a brief statement of the facts requiring such
adjustment. Unless and until a Responsible Officer of the Trustee shall have
received such Officers' Certificate, the Trustee shall not be deemed to have
knowledge of any adjustment of the Conversion Rate and may assume without
inquiry that the last Conversion Rate of which it has knowledge is still in
effect. Promptly after delivery of such certificate, the Company shall prepare a
notice of such adjustment of the Conversion Rate setting forth the adjusted
Conversion Rate and the date on which each adjustment becomes effective and
shall mail such notice of such adjustment of the Conversion Rate to the holder
of each Note at his last address appearing on the Note register provided for in
Section 2.5 of this Indenture, within twenty (20) days

                                      -74-

<PAGE>

after execution thereof. Failure to deliver such notice shall not affect the
legality or validity of any such adjustment.

          (l) In any case in which this Section 15.5 provides that an adjustment
shall become effective immediately after (1) a record date or Record Date for an
event, (2) the date fixed for the determination of stockholders entitled to
receive a dividend or distribution pursuant to Section 15.5(a), (3) a date fixed
for the determination of stockholders entitled to receive rights or warrants
pursuant to Section 15.5(b), (4) the Expiration Time for any tender or exchange
offer pursuant to Section 15.5(f), or (5) the Offer Expiration Time for a tender
or exchange offer pursuant to Section 15.5(g) (each a "Determination Date"), the
Company may elect to defer until the occurrence of the relevant Adjustment Event
(as hereinafter defined) (x) issuing to the holder of any Note converted after
such Determination Date and before the occurrence of such Adjustment Event, the
additional shares of Common Stock or other securities issuable upon such
conversion by reason of the adjustment required by such Adjustment Event over
and above the Common Stock issuable upon such conversion before giving effect to
such adjustment and (y) paying to such holder any amount in cash in lieu of any
fraction pursuant to Section 15.3. For purposes of this Section 15.5(l), the
term "Adjustment Event" shall mean:

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

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

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

               (d) in any case referred to in clause (4) or clause (5) hereof,
          the date a sale or exchange of Common Stock pursuant to such tender or
          exchange offer is consummated and becomes irrevocable.

          (m) For purposes of this Section 15.5, the number of shares of Common
Stock at any time outstanding shall not include shares held in the treasury of
the Company but shall include shares issuable in respect of scrip certificates
issued in lieu of fractions of shares of Common Stock. The Company will not pay
any dividend or make any distribution on shares of Common Stock held in the
treasury of the Company.

     Section 15.6 Effect of Reclassification, Consolidation, Merger or Sale. If
                  ---------------------------------------------------------
any of the following events occur, namely (i) any reclassification or change of
the outstanding shares of Common Stock (other than a subdivision or combination
to which Section 15.5(c) applies), (ii) any consolidation, merger or combination
of the Company with another Person as a result of which holders of Common Stock
shall be entitled to receive stock, other securities or other property or assets
(including cash) with respect to or in exchange for such Common Stock, or (iii)
any sale or conveyance of all or substantially all of the properties and assets
of the Company to any other Person as a result of which holders of Common Stock
shall be entitled to receive stock, other securities or

                                      -75-

<PAGE>

other property or assets (including cash) with respect to or in exchange for
such Common Stock, then the Company or the successor or purchasing Person, as
the case may be, shall execute with the Trustee a supplemental indenture (which
shall comply with the Trust Indenture Act as in force at the date of execution
of such supplemental indenture) providing that such Note shall be convertible
(except for periods in which the Notes shall be convertible into cash pursuant
to a Cash Conversion Notice) into the kind and amount of shares of stock, other
securities or other property or assets (including cash) receivable upon such
reclassification, change, consolidation, merger, combination, sale or conveyance
by a holder of a number of shares of Common Stock issuable upon conversion of
such Notes (assuming, for such purposes, a sufficient number of authorized
shares of Common Stock are available to convert all such Notes) immediately
prior to such reclassification, change, consolidation, merger, combination, sale
or conveyance assuming such holder of Common Stock did not exercise his rights
of election, if any, as to the kind or amount of stock, other securities or
other property or assets (including cash) receivable upon such reclassification,
change, consolidation, merger, combination, sale or conveyance (provided that,
if the kind or amount of stock, other securities or other property or assets
(including cash) receivable upon such reclassification, change, consolidation,
merger, combination, sale or conveyance is not the same for each share of Common
Stock in respect of which such rights of election shall not have been exercised
("non-electing share"), then for the purposes of this Section 15.6 the kind and
amount of stock, other securities or other property or assets (including cash)
receivable upon such reclassification, change, consolidation, merger,
combination, sale or conveyance for each non-electing share shall be deemed to
be the kind and amount so receivable per share by a plurality of the
non-electing shares). Such supplemental indenture shall provide for adjustments
which shall be as nearly equivalent as may be practicable to the adjustments
provided for in this Article Fifteen.

     The Company shall cause notice of the execution of such supplemental
indenture to be mailed to each holder of Notes, at its address appearing on the
Note register provided for in Section 2.5 of this Indenture, within twenty (20)
days after execution thereof. Failure to deliver such notice shall not affect
the legality or validity of such supplemental indenture.

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

     If this Section 15.6 applies to any event or occurrence, Section 15.5 shall
not apply.

     Section 15.7 Taxes on Shares Issued. The issue of stock certificates on
                  ----------------------
conversions of Notes shall be made without charge to the converting Noteholder
for any tax in respect of the issue thereof. The Company shall not, however, be
required to pay any tax which may be payable in respect of any transfer involved
in the issue and delivery of stock in any name other than that of the holder of
any Note converted, and the Company shall not be required to issue or deliver
any such stock certificate unless and until the Person or Persons requesting the
issue thereof shall have paid to the Company the amount of such tax or shall
have established to the satisfaction of the Company that such tax has been paid.

                                      -76-


<PAGE>

     Section 15.8 Reservation of Shares; Shares to be Fully Paid; Compliance
                  ----------------------------------------------------------
with Governmental Requirements; Listing of Common Stock. The Company shall
-------------------------------------------------------
provide, free from preemptive rights, out of its authorized but unissued shares
or shares held in treasury, sufficient shares of Common Stock to provide for the
conversion of the Notes from time to time as such Notes are presented for
conversion.

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

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

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

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

     Section 15.9 Responsibility of Trustee. The Trustee and any other
                  -------------------------
conversion agent shall not at any time be under any duty or responsibility to
any holder of Notes to determine the Conversion Rate or whether any facts exist
which may require any adjustment of the Conversion Rate, or with respect to the
nature or extent or calculation of any such adjustment when made, or with
respect to the method employed, or herein or in any supplemental indenture
provided to be employed, in making the same. The Trustee and any other
conversion agent shall not be accountable with respect to the validity or value
(or the kind or amount) of any shares of Common Stock, or of any securities or
property, which may at any time be issued or delivered upon the conversion of
any Note; and the Trustee and any other conversion agent make no representations
with respect thereto. Neither the Trustee nor any conversion agent shall be
responsible for any failure of the Company to

                                      -77-

<PAGE>

issue, transfer or deliver any shares of Common Stock or stock certificates or
other securities or property or cash upon the surrender of any Note for the
purpose of conversion or to comply with any of the duties, responsibilities or
covenants of the Company contained in this Article Fifteen. Without limiting the
generality of the foregoing, neither the Trustee nor any conversion agent shall
be under any responsibility to determine the correctness of any provisions
contained in any supplemental indenture entered into pursuant to Section 15.6
relating either to the kind or amount of shares of stock or securities or
property (including cash) receivable by Noteholders upon the conversion of their
Notes after any event referred to in such Section 15.6 or to any adjustment to
be made with respect thereto, but, subject to the provisions of Section 8.1, may
accept as conclusive evidence of the correctness of any such provisions, and
shall be protected in relying upon, the Officers' Certificate (which the Company
shall be obligated to file with the Trustee prior to the execution of any such
supplemental indenture) with respect thereto.

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

          (a) the Company shall declare a dividend (or any other distribution)
on its Common Stock that would require an adjustment in the Conversion Rate
pursuant to Section 15.5; or

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

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

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

the Company shall cause to be filed with the Trustee and to be mailed to each
holder of Notes at his address appearing on the Note register provided for in
Section 2.5 of this Indenture, as promptly as possible but in any event at least
ten (10) days prior to the applicable date hereinafter specified, a notice
stating (x) the date on which a record is to be taken for the purpose of such
dividend, distribution or rights or warrants, or, if a record is not to be
taken, the date as of which the holders of Common Stock of record to be entitled
to such dividend, distribution or rights are to be determined, or (y) the date
on which such reclassification, consolidation, merger, sale, transfer,
dissolution, liquidation or winding up is expected to become effective or occur,
and the date as of which it is expected that holders of Common Stock of record
shall be entitled to exchange their Common Stock for securities or other
property deliverable upon such reclassification, consolidation, merger, sale,
transfer, dissolution, liquidation or winding up. Failure to give such notice,
or any defect therein, shall not affect the legality or validity of such
dividend, distribution, reclassification, consolidation, merger, sale, transfer,
dissolution, liquidation or winding up.

                                      -78-


<PAGE>

                                ARTICLE SIXTEEN

                            MISCELLANEOUS PROVISIONS

     Section 16.1 Provisions Binding on Company's Successors. All the covenants,
                  ------------------------------------------
stipulations, promises and agreements by the Company contained in this Indenture
shall bind its successors and assigns whether so expressed or not.

     Section 16.2 Official Acts by Successor Corporation. Any act or proceeding
                  --------------------------------------
by any provision of this Indenture authorized or required to be done or
performed by any board, committee or officer of the Company shall and may be
done and performed with like force and effect by the like board, committee or
officer of any Person that shall at the time be the lawful sole successor of the
Company.

     Section 16.3 Addresses for Notices, Etc. Any notice or demand which by any
                  --------------------------
provision of this Indenture is required or permitted to be given or served by
the Trustee or by the holders of Notes on the Company shall be deemed to have
been sufficiently given or made, for all purposes, if given or served by being
deposited postage prepaid by registered or certified mail in a post office
letter box addressed (until another address is filed by the Company with the
Trustee) to Riverstone Networks, Inc., 5200 Great America Parkway, Santa Clara,
California 95054, Attention: Chief Financial Officer. Any notice, direction,
request or demand hereunder to or upon the Trustee shall be deemed to have been
sufficiently given or made, for all purposes, if given or served by being
deposited, postage prepaid, by registered or certified mail in a post office
letter box addressed to the Corporate Trust Office, which office is, at the date
as of which this Indenture is dated, located at 633 West 5th Street, 12th Floor,
Los Angeles, California 90071, Attention: Corporate Trust Department (Riverstone
Networks, Inc. 3 3/4% Convertible Subordinated Notes due 2006).

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

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

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

     Section 16.4 Governing Law. This Indenture and each Note shall be deemed to
                  -------------
be a contract made under the laws of the State of New York, and for all purposes
shall be construed in accordance with the laws of the State of New York.

     Section 16.5 Evidence of Compliance with Conditions Precedent; Certificates
                  --------------------------------------------------------------
to Trustee. Upon any application or demand by the Company to the Trustee to take
----------
any action under any of the provisions of this Indenture, the Company shall
furnish to the Trustee an Officers' Certificate stating

                                      -79-

<PAGE>

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

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

     Section 16.6 Legal Holidays. In any case in which the date of maturity of
                  --------------
interest on or principal of the Notes or the date fixed for redemption of any
Note will not be a Business Day, then payment of such interest on or principal
of the Notes need not be made on such date, but may be made on the next
succeeding Business Day with the same force and effect as if made on the date of
maturity or the date fixed for redemption, and no interest shall accrue for the
period from and after such date.

     Section 16.7 Trust Indenture Act. This Indenture is hereby made subject to,
                  -------------------
and shall be governed by, the provisions of the Trust Indenture Act required to
be part of and to govern indentures qualified under the Trust Indenture Act;
provided, however, that, unless otherwise required by law, notwithstanding the
foregoing, this Indenture and the Notes issued hereunder shall not be subject to
the provisions of subsections (a)(1), (a)(2), and (a)(3) of Section 314 of the
Trust Indenture Act as now in effect or as hereafter amended or modified;
provided further that this Section 16.7 shall not require this Indenture or the
Trustee to be qualified under the Trust Indenture Act prior to the time such
qualification is in fact required under the terms of the Trust Indenture Act,
nor shall it constitute any admission or acknowledgment by any party to the
Indenture that any such qualification is required prior to the time such
qualification is in fact required under the terms of the Trust Indenture Act. If
any provision hereof limits, qualifies or conflicts with another provision
hereof which is required to be included in an indenture qualified under the
Trust Indenture Act, such required provision shall control.

     Section 16.8 No Security Interest Created. Nothing in this Indenture or in
                  ----------------------------
the Notes, expressed or implied, shall be construed to constitute a security
interest under the Uniform Commercial Code or similar legislation, as now or
hereafter enacted and in effect, in any jurisdiction in which property of the
Company or its subsidiaries is located.

     Section 16.9 Benefits of Indenture. Nothing in this Indenture or in the
                  ---------------------
Notes, express or implied, shall give to any Person, other than the parties
hereto, any paying agent, any authenticating agent, any Note registrar and their
successors hereunder, the holders of Notes and the holders of Senior
Indebtedness, any benefit or any legal or equitable right, remedy or claim under
this Indenture.

                                      -80-


<PAGE>

     Section 16.10 Table of Contents, Headings, Etc. The table of contents and
                   --------------------------------
the titles and headings of the articles and sections of this Indenture have been
inserted for convenience of reference only, are not to be considered a part
hereof, and shall in no way modify or restrict any of the terms or provisions
hereof.

     Section 16.11 Authenticating Agent. The Trustee may appoint an
                   --------------------
authenticating agent that shall be authorized to act on its behalf, and subject
to its direction, in the authentication and delivery of Notes in connection with
the original issuance thereof and transfers and exchanges of Notes hereunder,
including under Sections 2.4, 2.5, 2.6, 2.7, 3.3 and 3.5, as fully to all
intents and purposes as though the authenticating agent had been expressly
authorized by this Indenture and those Sections to authenticate and deliver
Notes. For all purposes of this Indenture, the authentication and delivery of
Notes by the authenticating agent shall be deemed to be authentication and
delivery of such Notes "by the Trustee" and a certificate of authentication
executed on behalf of the Trustee by an authenticating agent shall be deemed to
satisfy any requirement hereunder or in the Notes for the Trustee's certificate
of authentication. Such authenticating agent shall at all times be a Person
eligible to serve as trustee hereunder pursuant to Section 8.9.

     Any corporation into which any authenticating agent may be merged or
converted or with which it may be consolidated, or any corporation resulting
from any merger, consolidation or conversion to which any authenticating agent
shall be a party, or any corporation succeeding to the corporate trust business
of any authenticating agent, shall be the successor of the authenticating agent
hereunder, if such successor corporation is otherwise eligible under this
Section 16.11, without the execution or filing of any paper or any further act
on the part of the parties hereto or the authenticating agent or such successor
corporation.

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

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

     The provisions of Sections 8.2, 8.3, 8.4, 9.3 and this Section 16.11 shall
be applicable to any authenticating agent.

                                      -81-


<PAGE>

     Section 16.12 Execution in Counterparts. This Indenture may be executed in
                   -------------------------
any number of counterparts, each of which shall be an original, but such
counterparts shall together constitute but one and the same instrument.

     Section 16.13 Severability. In case any provision in this Indenture or in
                   ------------
the Notes shall be invalid, illegal or unenforceable, then (to the extent
permitted by law) the validity, legality and enforceability of the remaining
provisions shall not in any way be affected or impaired thereby.

                                      -82-


<PAGE>

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


                                  RIVERSTONE NETWORKS, INC.


                                  By:          /s/ Romulus S. Pereira
                                       -----------------------------------------
                                       Name:  Romulus S. Pereira
                                       Title:   President & CEO


                                  STATE STREET BANK AND TRUST COMPANY OF
                                   CALIFORNIA, N.A.
                                  as Trustee


                                  By:          /s/ Stephen Rivero
                                       -----------------------------------------
                                       Name:  Stephen Rivero
                                       Title:   Vice President

                                      -83-


<PAGE>

                                    EXHIBIT A

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

     THE NOTE EVIDENCED HEREBY HAS NOT BEEN REGISTERED UNDER THE UNITED STATES
SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE
SECURITIES LAWS, AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD WITHIN THE UNITED
STATES OR TO, OR FOR THE ACCOUNT OR BENEFIT OF, UNITED STATES PERSONS EXCEPT AS
SET FORTH IN THE FOLLOWING SENTENCE. BY ITS ACQUISITION HEREOF, THE HOLDER (1)
REPRESENTS THAT IT IS (A) A "QUALIFIED INSTITUTIONAL BUYER" (AS DEFINED IN RULE
144A UNDER THE SECURITIES ACT), (B) AN INSTITUTIONAL "ACCREDITED INVESTOR" (AS
DEFINED IN RULE 501(A)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT)
("INSTITUTIONAL ACCREDITED INVESTOR"), OR (C) A NON-U.S. PERSON; (2) AGREES THAT
IT WILL NOT, PRIOR TO EXPIRATION OF THE HOLDING PERIOD APPLICABLE TO SALES OF
THE NOTE EVIDENCED HEREBY UNDER RULE 144(K) UNDER THE SECURITIES ACT (OR ANY
SUCCESSOR PROVISION), RESELL OR OTHERWISE TRANSFER THIS NOTE OR THE COMMON STOCK
ISSUABLE UPON CONVERSION OF THIS NOTE EXCEPT (A) TO RIVERSTONE NETWORKS, INC. OR
ANY SUBSIDIARY THEREOF, (B) INSIDE THE UNITED STATES TO A QUALIFIED
INSTITUTIONAL BUYER IN COMPLIANCE WITH RULE 144A UNDER THE SECURITIES ACT, (C)
INSIDE THE UNITED STATES TO AN INSTITUTIONAL ACCREDITED INVESTOR THAT, PRIOR TO
SUCH TRANSFER, FURNISHES TO STATE STREET BANK AND TRUST COMPANY OF CALIFORNIA,
N.A., AS TRUSTEE (OR A SUCCESSOR TRUSTEE, AS APPLICABLE), A SIGNED LETTER
CONTAINING CERTAIN REPRESENTATIONS AND AGREEMENTS RELATING TO THE RESTRICTIONS
ON TRANSFER OF THE NOTES (THE FORM OF WHICH LETTER CAN BE OBTAINED FROM SUCH
TRUSTEE OR A SUCCESSOR TRUSTEE, AS APPLICABLE), AND IF SUCH TRANSFER IS IN
RESPECT OF AN AGGREGATE PRINCIPAL AMOUNT OF NOTES OF LESS THAN $100,000, AN
OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY THAT SUCH TRANSFER IS IN COMPLIANCE
WITH THE SECURITIES ACT, (D) OUTSIDE THE UNITED STATES IN COMPLIANCE WITH RULE
904 UNDER THE SECURITIES ACT, (E) PURSUANT TO THE EXEMPTION FROM REGISTRATION

                                      A-1

<PAGE>

PROVIDED BY RULE 144 UNDER THE SECURITIES ACT (IF AVAILABLE) OR (F) PURSUANT TO
A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES
ACT (AND WHICH CONTINUES TO BE EFFECTIVE AT THE TIME OF SUCH TRANSFER); (3)
PRIOR TO SUCH TRANSFER (OTHER THAN A TRANSFER PURSUANT TO CLAUSE (2)(F) ABOVE),
IT WILL FURNISH TO STATE STREET BANK AND TRUST COMPANY OF CALIFORNIA, N.A., AS
TRUSTEE (OR A SUCCESSOR TRUSTEE, AS APPLICABLE), SUCH CERTIFICATIONS, LEGAL
OPINIONS OR OTHER INFORMATION AS THE TRUSTEE MAY REASONABLY REQUIRE TO CONFIRM
THAT SUCH TRANSFER IS BEING MADE PURSUANT TO AN EXEMPTION FROM, OR IN A
TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT;
AND (4) AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THIS NOTE IS
TRANSFERRED A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. IN CONNECTION
WITH ANY TRANSFER OF THIS NOTE PRIOR TO THE EXPIRATION OF THE HOLDING PERIOD
APPLICABLE TO SALES OF THIS NOTE UNDER RULE 144(K) UNDER THE SECURITIES ACT (OR
ANY SUCCESSOR PROVISION), THE HOLDER MUST CHECK THE APPROPRIATE BOX SET FORTH ON
THE REVERSE HEREOF RELATING TO THE MANNER OF SUCH TRANSFER AND SUBMIT THIS
CERTIFICATE TO STATE STREET BANK AND TRUST COMPANY OF CALIFORNIA, N.A., AS
TRUSTEE (OR A SUCCESSOR TRUSTEE, AS APPLICABLE). IF THE PROPOSED TRANSFEREE IS
AN INSTITUTIONAL ACCREDITED INVESTOR OR IS A PURCHASER WHO IS NOT A UNITED
STATES PERSON, THE HOLDER MUST, PRIOR TO SUCH TRANSFER, FURNISH TO STATE STREET
BANK AND TRUST COMPANY OF CALIFORNIA, N.A., AS TRUSTEE (OR A SUCCESSOR TRUSTEE,
AS APPLICABLE), SUCH CERTIFICATIONS, LEGAL OPINIONS OR OTHER INFORMATION AS SUCH
TRUSTEE MAY REASONABLY REQUIRE TO CONFIRM THAT SUCH TRANSFER IS BEING MADE
PURSUANT TO AN EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT. THIS LEGEND WILL BE REMOVED
UPON THE EARLIER OF THE TRANSFER OF THIS NOTE PURSUANT TO CLAUSE (2)(F) ABOVE OR
UPON ANY TRANSFER OF THIS NOTE UNDER RULE 144(K) UNDER THE SECURITIES ACT (OR
ANY SUCCESSOR PROVISION). AS USED HEREIN, THE TERMS "UNITED STATES" AND "U.S.
PERSON" HAVE THE MEANINGS GIVEN TO THEM BY REGULATION S UNDER THE SECURITIES
ACT. THE INDENTURE CONTAINS A PROVISION REQUIRING THE TRUSTEE TO REFUSE TO
REGISTER ANY TRANSFER OF THIS NOTE IN VIOLATION OF THE FOREGIONG RESTRICTION.

                                      A-2


<PAGE>

                            RIVERSTONE NETWORKS, INC.

                  3 3/4% CONVERTIBLE SUBORDINATED NOTE DUE 2006

                                                              CUSIP: ___________

No.: _____                                                          $___________

     Riverstone Networks, Inc., a corporation duly organized and validly
existing under the laws of the State of Delaware (herein called the "Company",
which term includes any successor corporation under the Indenture referred to on
the reverse hereof), for value received hereby promises to pay to
________________ or registered assigns, the principal sum of _______________
Dollars ($___________) on December 1, 2006, at the office or agency of the
Company maintained for that purpose in accordance with the terms of the
Indenture, in such coin or currency of the United States of America as at the
time of payment shall be legal tender for the payment of public and private
debts, and to pay interest, semi-annually on June 1 and December 1 of each year,
commencing June 1, 2002, on said principal sum at said office or agency, in like
coin or currency, at the rate per annum of 3 3/4%, from June 1 or December 1, as
the case may be, next preceding the date of this Note to which interest has been
paid or duly provided for, unless the date hereof is a date to which interest
has been paid or duly provided for, in which case from the date of this Note, or
unless no interest has been paid or duly provided for on the Notes, in which
case from November 21, 2001, until payment of said principal sum has been made
or duly provided for. Notwithstanding the foregoing, if the date hereof is after
any May 15 or November 15, as the case may be, and before the following June 1
or December 1, this Note shall bear interest from such June 1 or December 1;
provided, however, that if the Company shall default in the payment of interest
due on such June 1 or December 1, then this Note shall bear interest from the
next preceding June 1 or December 1 to which interest has been paid or duly
provided for or, if no interest has been paid or duly provided for on such Note,
from November 21, 2001. Except as otherwise provided in the Indenture, the
interest payable on the Note pursuant to the Indenture on any June 1 or December
1 will be paid to the Person entitled thereto as it appears in the Note register
at the close of business on the record date, which shall be the May 15 or
November 15 (whether or not a Business Day) next preceding such June 1 or
December 1, as provided in the Indenture; provided, however, that any such
interest not punctually paid or duly provided for shall be payable as provided
in the Indenture. Interest may, at the option of the Company, be paid either (i)
by check mailed to the registered address of such Person (provided that the
holder of Notes with an aggregate principal amount in excess of $2,000,000
shall, at the written election of such holder, be paid by wire transfer of
immediately available funds) or (ii) by transfer to an account maintained by
such Person located in the United States; provided, however, that payments to
the Depositary will be made by wire transfer of immediately available funds to
the account of the Depositary or its nominee.

     Reference is made to the further provisions of this Note set forth on the
reverse hereof, including, without limitation, provisions subordinating the
payment of principal of and premium, if any, and interest on the Notes to the
prior payment in full of all Senior Indebtedness, as defined in the Indenture,
and provisions giving the holder of this Note the right to convert this Note on
the

                                      A-3

<PAGE>

terms and subject to the limitations referred to on the reverse hereof and as
more fully specified in the Indenture. Such further provisions shall for all
purposes have the same effect as though fully set forth at this place.

     This Note shall be deemed to be a contract made under the laws of the State
of New York, and for all purposes shall be construed in accordance with and
governed by the laws of the State of New York.

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

                                      A-4


<PAGE>

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


                                   RIVERSTONE NETWORKS, INC.


                                   By:
                                        ----------------------------------------
                                        Name:  Romulus Pereira
                                        Title:  President and Chief Executive
                                                Officer

                                   Attest:


                                   By:
                                        ----------------------------------------
                                        Name:  Robert Stanton
                                        Title:  Secretary


Dated: ____________


TRUSTEE'S CERTIFICATE OF AUTHENTICATION

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

STATE STREET BANK AND TRUST COMPANY
  OF CALIFORNIA, N.A, as Trustee


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


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



                                      A-5


<PAGE>

                                 REVERSE OF NOTE

                            RIVERSTONE NETWORKS, INC.

                 3 3/4% CONVERTIBLE SUBORDINATED NOTES DUE 2006

     This Note is one of a duly authorized issue of Notes of the Company,
designated as its 3 3/4% Convertible Subordinated Notes Due 2006 (herein called
the "Notes"), limited to the aggregate principal amount of $175,000,000, all
issued or to be issued under and pursuant to an Indenture dated as of November
21, 2001 (herein called the "Indenture"), between the Company and State Street
Bank and Trust Company of California, N.A., as trustee (herein called the
"Trustee"), to which Indenture and all indentures supplemental thereto reference
is hereby made for a description of the rights, limitations of rights,
obligations, duties and immunities thereunder of the Trustee, the Company and
the holders of the Notes.

     In case an Event of Default (as defined in the Indenture) shall have
occurred and be continuing, the principal of, premium, if any, and accrued
interest (including Liquidated Damages (as defined in the Registration Rights
Agreement), if any) on all Notes may be declared by either the Trustee or the
holders of not less than 25% in aggregate principal amount of the Notes then
outstanding, and upon said declaration shall become, due and payable, in the
manner, with the effect and subject to the conditions provided in the Indenture.


     The Indenture contains provisions permitting the Company and the Trustee,
with the consent of the holders of not less than a majority in aggregate
principal amount of the Notes at the time outstanding, to execute supplemental
indentures adding any provisions to or changing in any manner or eliminating any
of the provisions of the Indenture or of any supplemental indenture or modifying
in any manner the rights of the holders of the Notes; provided, however, that no
such supplemental indenture shall (i) extend the fixed maturity of any Note, or
reduce the rate or extend the time of payment of interest thereon, or reduce the
principal amount thereof or premium, if any, thereon, or reduce any amount
payable upon redemption or repurchase thereof, or impair the right of any
Noteholder to institute suit for the payment thereof, or make the principal
thereof or interest or premium, if any, thereon payable in any coin or currency
other than that provided in the Notes, or modify the provisions of the Indenture
with respect to the subordination of the Notes in a manner adverse to the
Noteholders in any material respect, or change the obligation of the Company to
redeem any Note upon the happening of a Fundamental Change (as defined in the
Indenture) in a manner adverse to the holders of the Notes, or impair the right
to convert the Notes subject to the terms set forth in the Indenture, including
Section 15.6 thereof, or decrease the amount of cash payable if the Company
elects the cash payment option upon conversion, without the consent of the
holder of each Note so affected or (ii) reduce the aforesaid percentage of
Notes, the holders of which are required to consent to any such supplemental
indenture, without the consent of the holders of all Notes then outstanding.
Subject to the provisions of the Indenture, the holders of a majority in
aggregate principal amount of the Notes at the time outstanding may on behalf of
the holders of all of the Notes waive any past default or Event of Default under
the Indenture and its consequences

                                      A-6

<PAGE>

except a default in the payment of interest (including Liquidated Damages, if
any) or any premium on, or the principal of, any of the Notes, or a failure by
the Company to make any required conversion of Notes into Common Stock of the
Company or make any payment of cash required upon conversion of the Notes, or a
default in the payment of the redemption price pursuant to Article Three of the
Indenture, or a default in respect of a covenant or provisions of the Indenture
which under Article Eleven of the Indenture cannot be modified without the
consent of the holders of each or all Notes then outstanding or affected
thereby. Any such consent or waiver by the holder of this Note (unless revoked
as provided in the Indenture) shall be conclusive and binding upon such holder
and upon all future holders and owners of this Note and any Notes which may be
issued in exchange or substitution hereof, irrespective of whether or not any
notation thereof is made upon this Note or such other Notes.

     The indebtedness evidenced by the Notes is, to the extent and in the manner
provided in the Indenture, expressly subordinated and subject in right of
payment to the prior payment in full of all Senior Indebtedness (as defined in
the Indenture) of the Company, whether outstanding at the date of the Indenture
or thereafter incurred, and this Note is issued subject to the provisions of the
Indenture with respect to such subordination. Each holder of this Note, by
accepting the same, agrees to and shall be bound by such provisions and
authorizes the Trustee on its behalf to take such action as may be necessary or
appropriate to effectuate the subordination so provided and appoints the Trustee
his attorney-in-fact for such purpose.

     No reference herein to the Indenture and no provision of this Note or of
the Indenture shall alter or impair the obligation of the Company, which is
absolute and unconditional, to pay the principal of and any premium and interest
(including Liquidated Damages, if any) on this Note at the place, at the
respective times, at the rate and in the coin or currency herein prescribed.

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

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

     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 December 3, 2004 (a "Provisional
Redemption"), upon notice as set forth in Section 3.2 of the Indenture, at a
redemption price equal to $1,000 per $1,000 aggregate principal amount of the
Notes redeemed if: (1) the Closing Price of the Common Stock has exceeded 150%
of the Conversion Price (as such may be adjusted from time to time) then in
effect for at least 20 Trading Days within a period of 30 consecutive Trading
Days ending on the Trading Day prior to the date of mailing of the provisional
notice of redemption pursuant to Section 3.2 of the Indenture (the "Notice
Date"), and (2) if the redemption occurs prior to November 21, 2003, a
registration

                                      A-7

<PAGE>

statement covering resales of the Notes and the Common Stock issuable upon
conversion thereof is effective and available for use and is expected to remain
effective 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 in cash (the "Make-Whole Payment") with respect to the Notes called for
redemption to holders on the Notice Date equal to the aggregate amount of the
interest otherwise payable on the Notes from the last day through which interest
was paid on the Notes, or November 21, 2001 if no interest has been paid,
through December 3, 2004. 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.

     At any time on or after December 3, 2004, and prior to maturity, the Notes
may be redeemed at the option of the Company, in whole or in part, upon mailing
a notice of such redemption not less than 30 nor more than 60 days before the
date fixed for redemption to the holders of Notes at their last registered
addresses, all as provided in the Indenture, at the following Non-Provisional
Redemption prices (expressed as percentages of the principal amount), together
in each case with accrued and unpaid interest (including Liquidated Damages, if
any) to, but excluding, the date fixed for redemption:

Period                                                        Redemption Price
------                                                        ----------------
Beginning on December 3, 2004 and ending on
 November 30, 2005                                                101.50%

Beginning on December 1, 2005 and ending on
 November 30, 2006                                                100.75%

and 100% on December 1, 2006; provided, however, that if the date fixed for
redemption is on June 1 or December 1, then the interest payable on such date
shall be paid to the holder of record on the preceding May 15 or November 15,
respectively. In order to make a cash payment in lieu of issuing shares of
Common Stock upon any conversion of any Notes called for redemption, the
redemption notice must specify such election to settle the conversion in cash.

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

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

     If a Fundamental Change occurs at any time prior to maturity of the Notes,
the Notes will be redeemable on the 30th day after notice thereof (or, if such
30th day is not a Business Day, the immediately preceding Business Day) (the
"Repurchase Date") at the option of the holder of the Notes at a redemption
price equal to 100% of the principal amount thereof, together with accrued
interest to (but excluding) the date of redemption; provided, however, that, if
such Repurchase Date is a June 1 or December 1, the interest payable on such
date shall be paid to the holder of record of the Notes on the preceding May 15
or November 15, respectively. The Notes will be redeemable in multiples of
$1,000 principal amount. The Company or, as provided in the Indenture, the
Trustee, shall mail to all holders of record of the Notes a notice of the
occurrence of a Fundamental Change and of the redemption right arising as a
result thereof on or before the 10th day after the occurrence

                                      A-8

<PAGE>

of such Fundamental Change. For a Note to be so redeemed at the option of the
holder, the Company must receive at the office or agency of the Company
maintained for that purpose in accordance with the terms of the Indenture, such
Note with the form entitled "Option to Elect Repayment Upon a Fundamental
Change" on the reverse thereof duly completed, together with such Note, duly
endorsed for transfer, on or before the Fundamental Change Expiration Time (as
defined in the Indenture).

     Subject to the provisions of the Indenture, the holder hereof has the
right, at its option, at any time after the original issuance of any Notes
through the close of business on the final maturity date of the Notes, or, as to
all or any portion hereof called for redemption, prior to the close of business
on the Business Day immediately preceding the date fixed for redemption (unless
the Company shall default in payment due upon redemption thereof), to convert
the principal hereof or any portion of such principal which is $1,000 or an
integral multiple thereof into that number of shares of the Company's Common
Stock (as such shares shall be constituted at the date of conversion) at an
initial Conversion Rate of 55.0661 shares of Common Stock per $1,000 principal
amount of Notes, as may adjusted from time to time as provided in the Indenture,
upon surrender of this Note, together with a conversion notice as provided in
the Indenture (the form entitled "Conversion Notice" on the reverse hereof), to
the Company at the office or agency of the Company maintained for that purpose
in accordance with the terms of the Indenture, or at the option of such holder,
the Corporate Trust Office as provided in the Indenture, and, unless the shares
issuable on conversion are to be issued in the same name as this Note, duly
endorsed by, or accompanied by instruments of transfer in form satisfactory to
the Company duly executed by, the holder or by his duly authorized attorney.

     In lieu of issuing shares of the Company's Common Stock upon conversion,
the Company may elect to pay cash, but only with 30 days prior written notice to
all holders of Notes. If the Company elects to convert this Note into cash, it
will pay the holder hereof an amount equal to 105% of the value of the Common
Stock the holder would have received had its Notes been converted into shares of
the Company's Common Stock. The value of the Common Stock will be based on the
last reported sale price for the Company's Common Stock on the date of
conversion unless shares of such Common Stock are not approved for quotation on
the Nasdaq National Market or any similar United States system of automated
dissemination of quotations of securities prices, in which case such value will
be based on the good faith estimate of the Company's Board of Directors.

     In order to convert this Note into cash, the Company must have previously
provided to all holders of the Notes and the Trustee 30 days prior written
notice of its election to do so. Any such notice shall apply to conversion after
the effective time of such notice and until such notice terminates or is
revoked. The Company may revoke any such notice and, with 30 days prior written
notice, the Company may reinstate any revoked or terminated notice. The Company
will only pay cash in lieu of issuing Common Stock upon conversion of any Notes
called for redemption by the Company if the notice of redemption specifies the
Company's intention to pay cash upon conversion.

     Any cash payment made in settlement of conversion will be made on the
second Business Day following the conversion date. If the Company fails to make
the cash payment on the second

                                      A-9

<PAGE>

Business Day following the conversion date, the holder hereof has the right to
elect to receive shares of Common Stock in lieu of such payment.

     No adjustment in respect of interest on any Note converted or dividends on
any shares issued upon conversion of such Note will be made upon any conversion
except as set forth in the next sentence. If this Note (or portion hereof) is
surrendered for conversion during the period from the close of business on any
record date for the payment of interest to the close of business on the Business
Day preceding the following interest payment date and either (x) has not been
called for redemption on a redemption date that occurs during such period or (y)
is not to be redeemed in connection with a Fundamental Change on a Repurchase
Date that occurs during such period, this Note (or portion hereof being
converted) must be accompanied by an amount, in New York Clearing House funds or
other funds acceptable to the Company, equal to the interest payable on such
interest payment date on the principal amount being converted; provided,
however, that no such payment shall be required if there shall exist at the time
of conversion a default in the payment of interest on the Notes. No fractional
shares will be issued upon any conversion, but an adjustment and payment in cash
will be made, as provided in the Indenture, in respect of any fraction of a
share which would otherwise be issuable upon the surrender of any Note or Notes
for conversion. A Note in respect of which a holder is exercising its right to
require redemption upon a Fundamental Change may be converted only if such
holder withdraws its election to exercise such right in accordance with the
terms of the Indenture. Any Notes called for redemption, unless surrendered for
conversion by the holders thereof on or before the close of business on the
Business Day preceding the date fixed for redemption, may be deemed to be
redeemed from the holders of such Notes for an amount equal to the applicable
redemption price, together with accrued but unpaid interest (including
Liquidated Damages, if any) to (but excluding) the date fixed for redemption, by
one or more investment banks or other purchasers who may agree with the Company
(i) to purchase such Notes from the holders thereof and convert them into shares
of the Company's Common Stock and (ii) to make payment for such Notes as
aforesaid to the Trustee in trust for the holders.

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

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

                                      A-10


<PAGE>

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

     This Note shall be deemed to be a contract made under the laws of New York,
and for all purposes shall be construed in accordance with the laws of New York.

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

                                      A-11


<PAGE>

                                  ABBREVIATIONS

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

     TEN COM - as tenants in common

     TEN ENT - as tenant by the entireties

     JT TEN - as joint tenants with right of survivorship and not as tenants in
     common

     UNIF GIFT MIN ACT - ____________ Custodian _____________
                            (Cust)                 (Minor)

     under Uniform Gifts to Minors Act

     ______________ ____________________________
                               (State)

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

                                      A-12


<PAGE>

                                CONVERSION NOTICE

TO:  RIVERSTONE NETWORKS, INC.

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

     Notwithstanding the foregoing, the undersigned registered owner of this
Note acknowledges that if the Company has previously provided notice of its
election to make a cash payment in lieu of issuing shares upon conversion in
accordance with the terms of the Indenture referred to in this Note, and such
notice has not been revoked or terminated, the Company shall make a cash payment
to the undersigned registered owner equal to 105% of the value of the Common
Stock that the undersigned registered owner would have received upon conversion
of this Note. The cash payment will be deposited with State Street Bank and
Trust Company of California, N.A., or one or more paying agents (or will be held
in trust by the Company, if it is acting as its own paying agent), in accordance
with the terms of the Indenture, in an amount of money in immediately available
funds sufficient to make such cash payment.

Dated: ___________________

                                        ________________________________________


                                        ________________________________________
                                        Signature(s)

                                        Signature(s) must be guaranteed by an
                                        "eligible guarantor institution" meeting
                                        the requirements of the Note registrar,
                                        which requirements include membership or
                                        participation in the Security Transfer
                                        Agent Medallion Program ("STAMP") or
                                        such other "signature guarantee program"
                                        as may be determined by the Note
                                        registrar in addition to, or in
                                        substitution for, STAMP, all in
                                        accordance with the Securities Exchange
                                        Act of 1934, as amended.

                                      A-13


<PAGE>

                                         _______________________________________
                                         Signature Guarantee

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

_______________________________________
(Name)

_______________________________________
(Street Address)

_______________________________________
(City, State and Zip Code)

_______________________________________
Please print name and address

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

$______________________________________


Social Security or Other Taxpayer
Identification Number:

_______________________________________



                                      A-14


<PAGE>

                            OPTION TO ELECT REPAYMENT

                            UPON A FUNDAMENTAL CHANGE

TO:  RIVERSTONE NETWORKS, INC.

     The undersigned registered owner of this Note hereby irrevocably
acknowledges receipt of a notice from Riverstone Networks, Inc. (the "Company")
as to the occurrence of a Fundamental Change with respect to the Company and
requests and instructs the Company to repay the entire principal amount of this
Note, or the portion thereof (which is $1,000 or an integral multiple thereof)
below designated, in accordance with the terms of the Indenture referred to in
this Note at the price of 100% of such entire principal amount or portion
thereof, together with accrued interest to, but excluding, such repayment date,
to the registered holder hereof.

Dated: ___________________

                                        ________________________________________


                                        ________________________________________
                                        Signature(s)

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

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

                                        $_______________________________________


                                        ________________________________________
                                        Social Security or Other
                                        Taxpayer Identification Number

                                      A-15


<PAGE>

                                   ASSIGNMENT

     FOR VALUE RECEIVED the undersigned hereby sell(s), assign(s) and
transfer(s) unto


__________________________________________________________


__________________________________________________________


PLEASE INSERT SOCIAL SECURITY OR
OTHER IDENTIFYING NUMBER OF ASSIGNEE

_______________________________________


________________________________________________________________________________


__________________________________________________________


__________________________________________________________
        (Please print or typewrite name and address
           including postal zip code of assignee)


__________________________________________________________

the within Note and all rights thereunder, and hereby irrevocably constitutes
and appoints


__________________________________________________________

Attorney to transfer said Note on the books of the Company, with full power of
substitution in the premises.

     In connection with any transfer of the Note within the "United States" or
to, or for the account of, "U.S. persons" (in each case as defined in Regulation
S under the Securities Act) and 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) (other han any transfer pursuant to
a registration statement that has been declared effective under the Securities
Act), the undersigned confirms that such Note is being transferred:

                                      A-16


<PAGE>

     [_]  To Riverstone Networks, Inc. or a subsidiary thereof; or


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

     [_]  To an Institutional Accredited Investor pursuant to and in compliance
          with the Securities Act of 1933, as amended, in a minimum denomination
          of $200,000; or

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

and unless the box below is checked, the undersigned confirms that such Note is
not being transferred to an "affiliate" of the Company as defined in Rule 144
under the Securities Act of 1933, as amended (an "Affiliate").

     [_]  The transferee is an Affiliate of the Company. Dated:

Dated:______________________

                                        ________________________________________


                                        ________________________________________
                                        Signature(s)

                                        Signature(s) must be guaranteed by an
                                        "eligible guarantor institution" meeting
                                        the requirements of the Note registrar,
                                        which requirements include membership or
                                        participation in the Security Transfer
                                        Agent Medallion Program ("STAMP") or
                                        such other "signature guarantee program"
                                        as may be determined by the Note
                                        registrar in addition to, or in
                                        substitution for, STAMP, all in
                                        accordance with the Securities Exchange
                                        Act of 1934, as amended.


                                        ________________________________________
                                        Signature Guarantee

     NOTICE: The signature of the conversion notice, the option to elect
repayment upon a Fundamental Change or the assignment must correspond with the
name as written upon the face of the Note in every particular without alteration
or enlargement or any change whatever.

                                      A-17


<PAGE>

                                    EXHIBIT B

Riverstone Networks, Inc.
5200 Great America Parkway
Santa Clara, CA  95054

State Street Bank and Trust Company
  of California, N.A.
633 West 5th Street, 12th Floor
Los Angeles, CA  90071

Attention: Corporate Trust Department

Ladies and Gentlemen:

     In connection with our proposed purchase of 3 3/4% Convertible Subordinated
Notes Due 2006 (the "Notes") of Riverstone Networks, Inc., a Delaware
corporation (the "Company"), we confirm that:

          (i) we are an "accredited investor" within the meaning of Rule
     501(a)(1), (2) or (3) under the Securities Act of 1933, as amended (the
     "Securities Act"), or an entity in which all of the equity owners are
     accredited investors within the meaning of Rule 501(a)(1), (2) or (3) under
     the Securities Act (an "Institutional Accredited Investor");

          (ii) (A) any purchase of Notes by us will be for our own account or
     for the account of one or more other Institutional Accredited Investors or
     as fiduciary for the account of one or more trusts, each of which is an
     "accredited investor" within the meaning of Rule 501(a)(7) under the
     Securities Act and for each of which we exercise sole investment discretion
     or (B) we are a "bank," within the meaning of Section 3(a)(2) of the
     Securities Act, or a "savings and loan association" or other institution
     described in Section 3(a)(5)(A) of the Securities Act that is acquiring
     Notes as fiduciary for the account of one or more institutions for which we
     exercise sole investment discretion;

          (iii) in the event that we purchase any Notes, we will acquire Notes
     having a minimum purchase price of not less than $200,000 for our own
     account or for any separate account for which we are acting;

          (iv) we have such knowledge and experience in financial and business
     matters that we are capable of evaluating the merits and risks of
     purchasing Notes; and

          (v) we are not acquiring Notes with a view to distribution thereof or
     with any present intention of offering or selling Notes or the Common Stock
     of the Company issuable upon conversion thereof, except as permitted below;
     provided that the disposition of our

                                      B-1

<PAGE>

     property and property of any accounts for which we are acting as fiduciary
     shall remain at all times within our control.

     We understand that the Notes are being offered in a transaction not
involving any public offering within the United States within the meaning of the
Securities Act and that the Notes and the Common Stock of the Company issuable
upon conversion thereof have not been registered under the Securities Act, and
we agree, on our own behalf and on behalf of each account for which we acquire
any Notes, that if in the future we decide to resell or otherwise transfer such
Notes or the Common Stock of the Company issuable upon conversion thereof, such
Notes or Common Stock of the Company may be resold or otherwise transferred
within the United States or to, or for the account or benefit of, U.S. persons
only (i) to the Company or any subsidiary thereof, (ii) to a person who is a
"qualified institutional buyer" (as defined in Rule 144A under the Securities
Act) in a transaction meeting the requirements of Rule 144A, (iii) to an
Institutional Accredited Investor that, prior to such transfer, furnishes to the
Trustee for the Notes (or in the case of Common Stock of the Company, the
transfer agent therefor) a signed letter containing certain representations and
agreements relating to the restrictions on transfer of such securities (the form
of which letter can be obtained from the Trustee or the transfer agent, as the
case may be), (iv) pursuant to the exemption from registration provided by Rule
144 under the Securities Act (if applicable), or (v) pursuant to a registration
statement that has been declared effective under the Securities Act (and which
continues to be effective at the time of such transfer), and in each case, in
accordance with any applicable securities law of any State of the U.S. and in
accordance with the legends set forth on the Notes or the Common Stock of the
Company issuable upon conversion thereof. We further agree to provide any person
purchasing any of the Notes or the Common Stock of the Company issuable upon
conversion thereof (other than pursuant to clause (iv) or (v) above) from us a
notice advising such purchaser that resales of such securities are restricted as
stated herein. We understand that the Trustee and transfer agent for the Notes
and the Common Stock of the Company will not be required to accept for
registration of transfer any Notes or any Common Stock of the Company issued
upon conversion of the Notes, except upon presentation of evidence satisfactory
to the Company that the foregoing restrictions on transfer have been complied
with. We further understand that any Notes and any Common Stock of the Company
issued upon conversion of the Notes will be in the form of definitive physical
certificates and that such certificates will bear a legend reflecting the
substance of this paragraph.

     The Company and the Trustee and their respective counsel are entitled to
rely upon this letter and are irrevocably authorized to produce this letter or a
copy hereof to any interested party in any administrative or legal proceeding or
official inquiry with respect to the matters covered hereby.

                                      B-2


<PAGE>

     THIS LETTER SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE
INTERNAL LAWS OF THE STATE OF NEW YORK. (Name of Purchaser)


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


                                     Address:
                                              -----------------------------

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

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


                                      B-3