<PAGE>
                                                                     Exhibit 4.1






                               CELL GENESYS, INC.

                                       TO

                           ___________________________

                                   AS TRUSTEE

                                    INDENTURE

                          DATED AS OF ___________, 200_









                             SENIOR DEBT SECURITIES
<PAGE>
                                TABLE OF CONTENTS

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ARTICLE 1 DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION....................................................     1

         Section 1.1     Definitions.................................................................................     1
         Section 1.2     Compliance Certificates and Opinions........................................................     8
         Section 1.3     Form of Documents Delivered to Trustee......................................................     9
         Section 1.4     Acts of Holders; Record Dates...............................................................     9
         Section 1.5     Notices, etc., to Trustee and Company.......................................................    11
         Section 1.6     Notice to Holders; Waiver...................................................................    12
         Section 1.7     Conflict with Trust Indenture Act...........................................................    12
         Section 1.8     Effect of Headings and Table of Contents....................................................    12
         Section 1.9     Successors and Assigns......................................................................    13
         Section 1.10    Separability Clause.........................................................................    13
         Section 1.11    Benefits of Indenture.......................................................................    13
         Section 1.12    Governing Law...............................................................................    13
         Section 1.13    Legal Holidays..............................................................................    13
         Section 1.14    Indenture and Securities Solely Corporate Obligations.......................................    13
         Section 1.15    Indenture May be Executed in Counterparts...................................................    14

ARTICLE 2 SECURITY FORMS.............................................................................................    14

         Section 2.1     Forms Generally.............................................................................    14
         Section 2.2     Form of Face of Security....................................................................    14
         Section 2.3     Form of Reverse of Security.................................................................    16
         Section 2.4     Form of Legend for Global Securities........................................................    21
         Section 2.5     Form of Trustee's Certificate of Authentication.............................................    21
         Section 2.6     Form of Conversion Notice...................................................................    21

ARTICLE 3 THE SECURITIES.............................................................................................    24

         Section 3.1     Amount Unlimited; Issuable in Series........................................................    24
         Section 3.2     Denominations...............................................................................    27
         Section 3.3     Execution, Authentication, Delivery and Dating..............................................    27
         Section 3.4     Temporary Securities........................................................................    28
         Section 3.5     Registration; Registration of Transfer and Exchange.........................................    29
         Section 3.6     Mutilated, Destroyed, Lost and Stolen Securities............................................    30
         Section 3.7     Payment of Interest; Interest Rights Preserved..............................................    31
         Section 3.8     Persons Deemed Owners.......................................................................    33
         Section 3.9     Cancellation................................................................................    33
         Section 3.10    Computation of Interest.....................................................................    33

ARTICLE 4 SATISFACTION AND DISCHARGE.................................................................................    33

         Section 4.1     Satisfaction and Discharge of Indenture.....................................................    33
</TABLE>


                                      -i-
<PAGE>
                                TABLE OF CONTENTS
                                   (CONTINUED)

<TABLE>
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         Section 4.2     Application of Trust Money..................................................................    34

ARTICLE 5 REMEDIES...................................................................................................    35

         Section 5.1     Events of Default...........................................................................    35
         Section 5.2     Acceleration of Maturity; Rescission and Annulment..........................................    36
         Section 5.3     Collection of Indebtedness and Suits for Enforcement by Trustee.............................    37
         Section 5.4     Trustee May File Proofs of Claim............................................................    38
         Section 5.5     Trustee May Enforce Claims Without Possession of Securities.................................    38
         Section 5.6     Application of Money Collected..............................................................    38
         Section 5.7     Limitation on Suits.........................................................................    39
         Section 5.8     Unconditional Right of Holders to Receive Principal, Premium and Interest and to Convert....    39
         Section 5.9     Restoration of Rights and Remedies..........................................................    40
         Section 5.10    Rights and Remedies Cumulative..............................................................    40
         Section 5.11    Delay or Omission Not Waiver................................................................    40
         Section 5.12    Control by Holders..........................................................................    40
         Section 5.13    Waiver of Past Defaults.....................................................................    41
         Section 5.14    Undertaking for Costs.......................................................................    41
         Section 5.15    Waiver of Usury, Stay or Extension Laws.....................................................    41

ARTICLE 6 THE TRUSTEE................................................................................................    42

         Section 6.1     Certain Duties and Responsibilities.........................................................    42
         Section 6.2     Notice of Defaults..........................................................................    42
         Section 6.3     Certain Rights of Trustee...................................................................    43
         Section 6.4     Not Responsible for Recitals or Issuance of Securities......................................    44
         Section 6.5     May Hold Securities and Act as Trustee under Other Indentures...............................    44
         Section 6.6     Money Held in Trust.........................................................................    44
         Section 6.7     Compensation and Reimbursement..............................................................    44
         Section 6.8     Conflicting Interests.......................................................................    45
         Section 6.9     Corporate Trustee Required; Eligibility.....................................................    45
         Section 6.10    Resignation and Removal; Appointment of Successor...........................................    45
         Section 6.11    Acceptance of Appointment by Successor......................................................    47
         Section 6.12    Merger, Conversion, Consolidation or Succession to Business.................................    48
         Section 6.13    Preferential Collection of Claims Against Company...........................................    48
         Section 6.14    Appointment of Authenticating Agent.........................................................    48

ARTICLE 7 HOLDERS' LISTS AND REPORTS BY TRUSTEE AND COMPANY..........................................................    50

         Section 7.1     Company to Furnish Trustee Names and Addresses of Holders...................................    50
         Section 7.2     Preservation of Information; Communications to Holders......................................    50
         Section 7.3     Reports by Trustee..........................................................................    51
</TABLE>


                                      -ii-
<PAGE>
                                TABLE OF CONTENTS
                                   (CONTINUED)

<TABLE>
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         Section 7.4     Reports by Company..........................................................................    51

ARTICLE 8 CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE.......................................................    51

         Section 8.1     Company May Consolidate, etc., Only on Certain Terms........................................    51
         Section 8.2     Successor Substituted.......................................................................    52

ARTICLE 9 SUPPLEMENTAL INDENTURES....................................................................................    53

         Section 9.1     Supplemental Indentures Without Consent of Holders..........................................    53
         Section 9.2     Supplemental Indentures with Consent of Holders.............................................    54
         Section 9.3     Execution of Supplemental Indentures........................................................    55
         Section 9.4     Effect of Supplemental Indentures...........................................................    55
         Section 9.5     Conformity with Trust Indenture Act.........................................................    56
         Section 9.6     Reference in Securities to Supplemental Indentures..........................................    56

ARTICLE 10 COVENANTS.................................................................................................    56

         Section 10.1    Payment of Principal, Premium and Interest..................................................    56
         Section 10.2    Maintenance of Office or Agency.............................................................    56
         Section 10.3    Money for Securities Payments To Be Held in Trust...........................................    57
         Section 10.4    Statement by Officers as to Default.........................................................    58
         Section 10.5    Existence...................................................................................    58
         Section 10.6    Maintenance of Properties...................................................................    58
         Section 10.7    Payment of Taxes and Other Claims...........................................................    58
         Section 10.8    Waiver of Certain Covenants.................................................................    59

ARTICLE 11 REDEMPTION OF SECURITIES..................................................................................    59

         Section 11.1    Applicability of Article....................................................................    59
         Section 11.2    Election to Redeem; Notice to Trustee.......................................................    59
         Section 11.3    Selection by Trustee of Securities to Be Redeemed...........................................    59
         Section 11.4    Notice of Redemption........................................................................    60
         Section 11.5    Deposit of Redemption Price.................................................................    61
         Section 11.6    Securities Payable on Redemption Date.......................................................    62
         Section 11.7    Securities Redeemed in Part.................................................................    62

ARTICLE 12 SINKING FUNDS.............................................................................................    62

         Section 12.1    Applicability of Article....................................................................    62
         Section 12.2    Satisfaction of Sinking Fund Payments with Securities.......................................    63
         Section 12.3    Redemption of Securities for Sinking Fund...................................................    63

ARTICLE 13 DEFEASANCE AND COVENANT DEFEASANCE........................................................................    63

         Section 13.1    Company's Option to Effect Defeasance or Covenant Defeasance................................    63
         Section 13.2    Defeasance and Discharge....................................................................    64
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                                     -iii-
<PAGE>
                                TABLE OF CONTENTS
                                   (CONTINUED)

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         Section 13.3    Covenant Defeasance.........................................................................    64
         Section 13.4    Conditions to Defeasance or Covenant Defeasance.............................................    65
         Section 13.5    Deposited Money, U.S. Government Obligations and Foreign Government Obligations to be
                         Held in Trust; Miscellaneous Provisions.....................................................    67
         Section 13.6    Reinstatement...............................................................................    67

ARTICLE 14 CONVERSION OF SECURITIES..................................................................................    68

         Section 14.1    Applicability of Article....................................................................    68
         Section 14.2    Exercise of Conversion Privilege............................................................    68
         Section 14.3    No Fractional Shares........................................................................    69
         Section 14.4    Adjustment of Conversion Price..............................................................    70
         Section 14.5    Notice of Certain Corporate Actions.........................................................    70
         Section 14.6    Reservation of Shares of Common Stock.......................................................    71
         Section 14.7    Payment of Certain Taxes upon Conversion....................................................    71
         Section 14.8    Nonassessability............................................................................    71
         Section 14.9    Provision in Case of Consolidation, Merger or Sale of Assets................................    71
         Section 14.10   Duties of Trustee Regarding Conversion......................................................    72
         Section 14.11   Repayment of Certain Funds upon Conversion..................................................    73
</TABLE>


                                      -iv-
<PAGE>
         Certain Sections of this Indenture relating to Sections 310 through
318, inclusive, of the Trust Indenture Act of 1939:

<TABLE>
<S>                                                                                                 <C>
Section 310(a)(1)..............................................................................................6.9
           (a)(2)..............................................................................................6.9
           (a)(3)...................................................................................Not Applicable
           (a)(4)...................................................................................Not Applicable
           (b)...........................................................................................6.8, 6.10
Section 311(a)................................................................................................6.13
           (b)................................................................................................6.13
Section 312(a)............................................................................................7.1, 7.2
           (b).................................................................................................7.2
           (c).................................................................................................7.2
Section 313(a).................................................................................................7.3
           (b).................................................................................................7.3
           (c).................................................................................................7.3
           (d).................................................................................................7.3
Section 314(a).................................................................................................7.4
           (a)(4)........................................................................................1.1, 10.4
           (b)......................................................................................Not Applicable
           (c)(1)..............................................................................................1.2
           (c)(2)..............................................................................................1.2
           (c)(3)...................................................................................Not Applicable
           (d)......................................................................................Not Applicable
           (e).................................................................................................1.2
Section 315(a).................................................................................................6.1
           (b).................................................................................................6.2
           (c).................................................................................................6.1
           (d).................................................................................................6.1
           (e)................................................................................................5.14
Section 316(a).................................................................................................1.1
           (a)(1)(A).....................................................................................5.2, 5.12
           (a)(1)(B)..........................................................................................5.13
           (a)(2)...................................................................................Not Applicable
           (b).................................................................................................5.8
           (c).................................................................................................1.4
Section 317(a)(1)..............................................................................................5.3
           (a)(2)..............................................................................................5.4
           (b)................................................................................................10.3
Section 318(a)................................................................................................ 1.7
</TABLE>

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


                                      -v-
<PAGE>
      INDENTURE, dated as of ____________, 200_, between Cell Genesys, Inc., a
corporation duly organized and existing under the laws of the State of Delaware
(herein called the "Company"), having its principal executive office at 342
Lakeside Drive, Foster City, California, and ______________________________, as
Trustee (herein called the "Trustee").

                             RECITALS OF THE COMPANY

      The Company has duly authorized the execution and delivery of this
Indenture to provide for the issuance from time to time of its unsecured
debentures, notes or other evidences of indebtedness (herein called the
"Securities"), to be issued in one or more series as provided in this Indenture.

      All things necessary to make this Indenture a valid agreement of the
Company, in accordance with its terms, have been done.

                   NOW, THEREFORE, THIS INDENTURE WITNESSETH:

      For and in consideration of the premises and the purchase of the
Securities by the Holders thereof, it is mutually covenanted and agreed, for the
equal and proportionate benefit of all Holders of the Securities or of series
thereof appertaining, as follows:

                                   ARTICLE 1

             DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

SECTION 1.1 DEFINITIONS.

      For all purposes of this Indenture, except as otherwise expressly provided
or unless the context otherwise requires:

            (1)   the terms defined in this Article have the meanings assigned
      to them in this Article and include the plural as well as the singular;

            (2)   all other terms used herein which are defined in the Trust
      Indenture Act, either directly or by reference therein, have the meanings
      assigned to them therein;

            (3)   all accounting terms not otherwise defined herein have the
      meanings assigned to them in accordance with generally accepted accounting
      principles in the United States of America, and, except as otherwise
      herein expressly provided, the term "generally accepted accounting
      principles" with respect to any computation required or permitted
      hereunder shall mean such accounting principles in the United States of
      America as are generally accepted at the date of such computation;

            (4)   all references to "$" refer to the lawful currency of the
      United States of America;
<PAGE>
            (5)   unless the context otherwise requires, any reference to an
      "Article" or a "Section" refers to an Article or a Section, as the case
      may be, of this Indenture; and

            (6)   the words "herein," "hereof" and "hereunder" and other words
      of similar import refer to this Indenture as a whole and not to any
      particular Article, Section or other subdivision.

      "Act," when used with respect to any Holder, has the meaning specified in
Section 1.4.

      "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.

      "Authenticating Agent" means any Person authorized by the Trustee pursuant
to Section 6.14 to act on behalf of the Trustee to authenticate Securities of
one or more series.

      "Board of Directors" means either the board of directors of the Company or
any duly authorized committee of that board empowered to act for it with respect
to this Indenture.

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

      "Business Day," when used with respect to any Place of Payment, means each
Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on which
banking institutions in that Place of Payment are authorized or obligated by law
or executive order to close.

      "Commission" means the Securities and Exchange Commission, from time to
time constituted, created under the Exchange Act, or, if at any time after the
execution of this instrument 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" includes 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; provided, however,
subject to the provisions of Section 14.9, shares issuable upon conversion of
Securities shall include only shares of the class designated as Common Stock of
the Company at the date of this Indenture 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, further, 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.


                                                                             -2-
<PAGE>
      "Company" means the corporation named as the "Company" in the first
paragraph of this instrument until a successor Person shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
"Company" shall mean such successor Person.

      "Company Request" or "Company Order" means a written request or order
signed in the name of the Company by its Chairman of the Board, its Vice
Chairman of the Board, its Chief Executive Officer, its President or a Vice
President, and by its principal financial officer, its Treasurer, an Assistant
Treasurer, its Secretary or an Assistant Secretary, and delivered to the
Trustee.

      "control" when used with respect to any specified Person means the power
to direct 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.

      "Corporate Trust Office" means the corporate trust office of the Trustee
at _____________ __________________, Attention: Corporate Trust Department, or
such other office, designated by the Trustee by written notice to the Company,
at which at any particular time its corporate trust business shall be
administered.

      "corporation" means a corporation, association, company, joint-stock
company or business trust.

      "Covenant Defeasance" has the meaning specified in Section 13.3.

      "Defaulted Interest" has the meaning specified in Section 3.7.

      "Defeasance" has the meaning specified in Section 13.2.

      "Depositary" means, with respect to Securities of any series issuable in
whole or in part in the form of one or more Global Securities, a clearing agency
registered under the Exchange Act that is designated to act as Depositary for
such Securities as contemplated by Section 3.1.

      "euro" or "euros" means the currency adopted by those nations
participating in the third stage of the economic and monetary union provisions
of the Treaty on European Union, signed at Maastricht on February 7, 1992.

      "European Economic Area" means the member nations of the European Economic
Area pursuant to the Oporto Agreement on the European Economic Area dated May 2,
1992, as amended.

      "European Union" means the member nations of the European Union
established by the Treaty of European Union, signed at Maastricht on February 2,
1992, which amended the Treaty of Rome establishing the European Community.

      "Event of Default" has the meaning specified in Section 5.1.


                                                                             -3-
<PAGE>
      "Exchange Act" means the Securities Exchange Act of 1934 and any statute
successor thereto, in each case as amended from time to time.

      "Expiration Date" has the meaning specified in Section 1.4.

      "Foreign Government Obligation" means with respect to Securities of any
series which are not denominated in the currency of the United States of America
(x) any security which is (i) a direct obligation of the government which issued
or caused to be issued the currency in which such security is denominated and
for the payment of which obligations its full faith and credit is pledged or,
with respect to Securities of any series which are denominated in euros, a
direct obligation of any member nation of the European Union for the payment of
which obligation the full faith and credit of the respective nation is pledged
so long as such nation has a credit rating at least equal to that of the highest
rated member nation of the European Economic Area, or (ii) an obligation of a
Person controlled or supervised by and acting as an agency or instrumentality of
a government specified in clause (i) above the payment of which is
unconditionally guaranteed as a full faith and credit obligation by the such
government, which, in either case (i) or (ii), is not callable or redeemable at
the option of the issuer thereof, and (y) any depositary receipt issued by a
bank (as defined in Section 3(a)(2) of the Securities Act) as custodian with
respect to any Foreign Government Obligation which is specified in clause (x)
above and held by such bank for the account of the holder of such depositary
receipt, or with respect to any specific payment of principal of or interest on
any Foreign Government Obligation which is so specified and held, provided that
(except as required by law) such custodian is not authorized to make any
deduction from the amount payable to the holder of such depositary receipt from
any amount received by the custodian in respect of the Foreign Government
Obligation or the specific payment of principal or interest evidenced by such
depositary receipt.

      "Global Security" means a Security that evidences all or part of the
Securities of any series and bears the legend set forth in Section 2.4 (or such
legend as may be specified as contemplated by Section 3.1 for such Securities).

      "Holder" means a Person in whose name a Security is registered in the
Security Register.

      "Indenture" means this instrument as originally executed and as it may
from time to time be supplemented or amended by one or more indentures
supplemental hereto entered into pursuant to the applicable provisions hereof,
including, for all purposes of this instrument and any such supplemental
indenture, the provisions of the Trust Indenture Act that are deemed to be a
part of and govern this instrument and any such supplemental indenture,
respectively. The term "Indenture" shall also include the terms of particular
series of Securities established as contemplated by Section 3.1; provided,
however, that if at any time more than one Person is acting as Trustee under
this Indenture due to the appointment of one or more separate Trustees for any
one or more separate series of Securities, "Indenture" shall mean, with respect
to such series of Securities for which any such Person is Trustee, this
instrument as originally executed or as it may from time to time be supplemented
or amended by one or more indentures supplemental hereto entered into pursuant
to the applicable provisions hereof and shall include the terms of particular
series of Securities for which such Person is Trustee established as
contemplated by Section 3.1, exclusive, however, of any


                                                                             -4-
<PAGE>
provisions or terms which relate solely to other series of Securities for which
such Person is not Trustee, regardless of when such terms or provisions were
adopted, and exclusive of any provisions or terms adopted by means of one or
more indentures supplemental hereto executed and delivered after such Person had
become such Trustee, but to which such person, as such Trustee, was not a party;
provided, further that in the event that this Indenture is supplemented or
amended by one or more indentures supplemental hereto which are only applicable
to certain series of Securities, the term "Indenture" for a particular series of
Securities shall only include the supplemental indentures applicable thereto.

      "interest," when used with respect to an Original Issue Discount Security,
which by its terms bears interest only after Maturity, means interest payable
after Maturity.

      "Interest Payment Date," when used with respect to any Security, means the
Stated Maturity of an installment of interest on such Security.

      "Investment Company Act" means the Investment Company Act of 1940 and any
statute successor thereto, in each case as amended from time to time.

      "Maturity," when used with respect to any Security, means the date on
which the principal of such Security or an installment of principal becomes due
and payable as therein or herein provided, whether at the Stated Maturity or by
declaration of acceleration, repurchase at the option of the Holder, upon
redemption or otherwise.

      "Notice of Default" means a written notice of the kind specified in
Section 5.1(4).

      "Officers' Certificate" means a certificate signed by the Chairman of the
Board, a Vice Chairman of the Board, the Chief Executive Officer, the President
or a Vice President, and by the principal financial officer, the Treasurer, an
Assistant Treasurer, the Secretary or an Assistant Secretary, of the Company,
and delivered to the Trustee. One of the officers signing an Officers'
Certificate given pursuant to Section 10.4 shall be the principal executive,
financial or accounting officer of the Company.

      "Opinion of Counsel" means a written opinion of counsel, who may be
counsel for, or an employee of, the Company, and who shall be reasonably
acceptable to the Trustee.

      "Original Issue Discount Security" means any Security that provides for an
amount less than the principal amount thereof to be due and payable upon a
declaration of acceleration of the Maturity thereof pursuant to Section 5.2.

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

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


                                                                             -5-
<PAGE>
            (2)   Securities for whose payment or redemption money in the
      necessary amount has been theretofore deposited with the Trustee or any
      Paying Agent (other than the Company) in trust or set aside and segregated
      in trust by the Company (if the Company shall act as its own Paying Agent)
      for the Holders of such Securities; provided that, if such Securities are
      to be redeemed, notice of such redemption has been duly given pursuant to
      this Indenture or provision therefor satisfactory to the Trustee has been
      made;

            (3)   Securities as to which Defeasance has been effected pursuant
      to Section 13.2; and

            (4)   Securities which have been paid pursuant to Section 3.6 or in
      exchange for or in lieu of which other Securities have been authenticated
      and delivered pursuant to this Indenture, other than any such Securities
      in respect of which there shall have been presented to the Trustee proof
      satisfactory to it that such Securities are held by a bona fide purchaser
      in whose hands such Securities are valid obligations of the Company;

provided, however, that in determining whether the Holders of the requisite
principal amount of the Outstanding Securities have given, made or taken any
request, demand, authorization, direction, notice, consent, waiver or other
action hereunder as of any date, (A) the principal amount of an Original Issue
Discount Security which shall be deemed to be Outstanding shall be the amount of
the principal thereof which would be due and payable as of such date upon
acceleration of the Maturity thereof to such date pursuant to Section 5.2, (B)
if, as of such date, the principal amount payable at the Stated Maturity of a
Security is not determinable, the principal amount of such Security which shall
be deemed to be Outstanding shall be the amount as specified or determined as
contemplated by Section 3.1, (C) the principal amount of a Security denominated
in one or more non-U.S. dollar currencies or currency units which shall be
deemed to be Outstanding shall be the U.S. dollar equivalent, determined as of
such date in the manner provided as contemplated by Section 3.1, of the
principal amount of such Security (or, in the case of a Security described in
clause (A) or (B) above, of the amount determined as provided in such clause),
and (D) Securities owned by the Company or any other obligor upon the Securities
or any Affiliate of the Company or of such other obligor shall be disregarded
and deemed not to be Outstanding, except that, in determining whether the
Trustee shall be protected in relying upon any such request, demand,
authorization, direction, notice, consent, waiver or other action, only
Securities which the Trustee knows to be so owned shall be so disregarded.
Securities so owned which have been pledged in good faith may be regarded as
Outstanding if the pledgee establishes to the satisfaction of the Trustee the
pledgee's right so to act with respect to such Securities and that the pledgee
is not the Company or any other obligor upon the Securities or any Affiliate of
the Company or of such other obligor.

      "Paying Agent" means any Person authorized by the Company to pay the
principal of or any premium or interest on any Securities on behalf of the
Company.

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


                                                                             -6-
<PAGE>
      "Place of Payment," when used with respect to the Securities of any
series, means the place or places where the principal of and any premium and
interest on the Securities of that series are payable as specified as
contemplated by Section 3.1.

      "Predecessor Security" of any particular Security means every previous
Security evidencing all or a portion of the same debt as that evidenced by such
particular Security; and, for the purposes of this definition, any Security
authenticated and delivered under Section 3.6 in exchange for or in lieu of a
mutilated, destroyed, lost or stolen Security shall be deemed to evidence the
same debt as the mutilated, destroyed, lost or stolen Security.

      "Record Date" means any Regular Record Date or Special Record Date.

      "Redemption Date," when used with respect to any Security to be redeemed,
means the date fixed for such redemption by or pursuant to this Indenture.

      "Redemption Price," when used with respect to any Security to be redeemed,
means the price at which it is to be redeemed pursuant to this Indenture.

      "Regular Record Date" for the interest payable on any Interest Payment
Date on the Securities of any series means the date specified for that purpose
as contemplated by Section 3.1.

      "Responsible Officer" means, when used with respect to the Trustee, an
officer of the Trustee in the Corporate Trust Office assigned and duly
authorized by the Trustee to administer its corporate trust matters.

      "Securities" has the meaning stated in the first recital of this Indenture
and more particularly means any Securities authenticated and delivered under
this Indenture.

      "Securities Act" means the Securities Act of 1933 and any statute
successor thereto, in each case as amended from time to time.

      "Security Register" and "Security Registrar" have the respective meanings
specified in Section 3.5.

      "Special Record Date" for the payment of any Defaulted Interest means a
date fixed by the Trustee pursuant to Section 3.7.

      "Stated Maturity," when used with respect to any Security or any
installment of principal thereof or interest thereon, means the date specified
in such Security as the fixed date on which the principal of such Security or
such installment of principal or interest is due and payable.

      "Subsidiary" means a Person of which at least a majority of the
outstanding voting stock having the power to elect a majority of the board of
directors of such Person (in the case of a corporation) is, or of which at least
a majority of the equity interests (in the case of a Person which is not a
corporation) are, at the time owned, directly or indirectly, by the Company or
by one or more


                                                                             -7-
<PAGE>
other Subsidiaries, or by the Company and one or more other Subsidiaries. For
the purposes of this definition, "voting stock" means stock which ordinarily has
voting power for the election of directors, whether at all times or only so long
as no senior class of stock has such voting power by reason of any contingency.

      "Trust Indenture Act" means the Trust Indenture Act of 1939 as in force at
the date as of which this instrument was executed; provided, however, that in
the event the Trust Indenture Act of 1939 is amended after such date, "Trust
Indenture Act" means, to the extent required by any such amendment, the Trust
Indenture Act of 1939 as so amended.

      "Trustee" means the Person named as the "Trustee" in the first paragraph
of this instrument until a successor Trustee shall have become such pursuant to
the applicable provisions of this Indenture, and thereafter "Trustee" shall mean
or include each Person who is then a Trustee hereunder, and if at any time there
is more than one such Person, "Trustee" as used with respect to the Securities
of any series shall mean the Trustee with respect to Securities of that series.

      "U.S. Government Obligation" means (x) any security which is (i) a direct
obligation of the United States of America for the payment of which the full
faith and credit of the United States of America is pledged or (ii) an
obligation of a Person controlled or supervised by and acting as an agency or
instrumentality of the United States of America the payment of which is
unconditionally guaranteed as a full faith and credit obligation by the United
States of America, which, in either case (i) or (ii), is not callable or
redeemable at the option of the issuer thereof, and (y) any depositary receipt
issued by a bank (as defined in Section 3(a)(2) of the Securities Act) as
custodian with respect to any U.S. Government Obligation which is specified in
clause (x) above and held by such bank for the account of the holder of such
depositary receipt, or with respect to any specific payment of principal of or
interest on any U.S. Government Obligation which is so specified and held,
provided that (except as required by law) such custodian is not authorized to
make any deduction from the amount payable to the holder of such depositary
receipt from any amount received by the custodian in respect of the U.S.
Government Obligation or the specific payment of principal or interest evidenced
by such depositary receipt.

         "Vice President," when used with respect to the Company or the Trustee,
means any vice president, whether or not designated by a number or a word or
words added before or after the title "vice president."

SECTION 1.2 COMPLIANCE CERTIFICATES AND OPINIONS.

      Upon any application or request by the Company to the Trustee to take any
action under any provision of this Indenture, the Company shall furnish to the
Trustee such certificates and opinions as may be required under the Trust
Indenture Act. Each such certificate or opinion shall be given in the form of an
Officers' Certificate, if to be given by an officer of the Company, or an
Opinion of Counsel, if to be given by counsel, and shall comply with the
requirements of the Trust Indenture Act and any other requirements set forth in
this Indenture.


                                                                             -8-
<PAGE>
         Every certificate or opinion with respect to compliance with a
condition or covenant provided for in this Indenture shall include,

            (1)   a statement that each individual signing such certificate or
      opinion has read such covenant or condition and the definitions herein
      relating thereto;

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

            (3)   a statement that, in the opinion of each such individual, he
      or she has made such examination or investigation as is necessary to
      enable him or her 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, in the opinion of each such
      individual, such condition or covenant has been complied with.

SECTION 1.3 FORM OF DOCUMENTS DELIVERED TO TRUSTEE.

      In any case where several matters are required to be certified by, or
covered by an opinion of, any specified Person, it is not necessary that all
such matters be certified by, or covered by the opinion of, only one such
Person, or that they be so certified or covered by only one document, but one
such Person may certify or give an opinion with respect to some matters and one
or more other such Persons as to other matters, and any such Person may certify
or give an opinion as to such matters in one or several documents.

      Any certificate or opinion of an officer of the Company may be based,
insofar as it relates to legal matters, upon a certificate or opinion of, or
representations by, counsel, unless such officer knows, or in the exercise of
reasonable care should know, that the certificate or opinion or representations
with respect to the matters upon which his or her certificate or opinion is
based are erroneous. Any such certificate or opinion of counsel may be based,
insofar as it relates to factual matters, upon a certificate or opinion of, or
representations by, an officer or officers of the Company stating that the
information with respect to such factual matters is in the possession of the
Company, unless such counsel knows, or in the exercise of reasonable care should
know, that the certificate or opinion or representations with respect to such
matters are erroneous.

      Where any Person is required to make, give or execute two or more
applications, requests, consents, certificates, statements, opinions or other
instruments under this Indenture, they may, but need not, be consolidated and
form one instrument.

SECTION 1.4 ACTS OF HOLDERS; RECORD DATES.

      Any request, demand, authorization, direction, notice, consent, waiver or
other action provided or permitted by this Indenture to be given, made or taken
by Holders may be embodied in and evidenced by one or more instruments of
substantially similar tenor signed by such Holders in person or by agent duly
appointed in writing; and, except as herein otherwise expressly provided,


                                                                             -9-
<PAGE>
such action shall become effective when such instrument or instruments are
delivered to the Trustee and, where it is hereby expressly required, to the
Company. The Trustee shall promptly deliver to the Company copies of all such
instrument or instruments delivered to the Trustee. Such instrument or
instruments (and the action embodied therein and evidenced thereby) are herein
sometimes referred to as the "Act" of the Holders signing such instrument or
instruments. Proof of execution of any such instrument or of a writing
appointing any such agent shall be sufficient for any purpose of this Indenture
and (subject to Section 6.1) conclusive in favor of the Trustee and the Company,
if made in the manner provided in this Section.

      The fact and date of the execution by any Person of any such instrument or
writing may be proved by the affidavit of a witness of such execution or by a
certificate of a notary public or other officer authorized by law to take
acknowledgments of deeds, certifying that the individual signing such instrument
or writing acknowledged to him or her the execution thereof. Where such
execution is by a signer acting in a capacity other than his or her individual
capacity, such certificate or affidavit shall also constitute sufficient proof
of his or her authority. The fact and date of the execution of any such
instrument or writing, or the authority of the Person executing the same, may
also be proved in any other manner that the Trustee deems sufficient.

      The ownership of Securities shall be proved by the Security Register.

      Any request, demand, authorization, direction, notice, consent, waiver or
other Act of the Holder of any Security shall bind every future Holder of the
same Security and the Holder of every Security issued upon the registration of
transfer thereof or in exchange therefor or in lieu thereof in respect of
anything done, omitted or suffered to be done by the Trustee or the Company in
reliance thereon, whether or not notation of such action is made upon such
Security.

      The Company may set any day as a record date for the purpose of
determining the Holders of Outstanding Securities of any series entitled to
give, make or take any request, demand, authorization, direction, vote, notice,
consent, waiver or other action provided or permitted by this Indenture to be
given, made or taken by Holders of Securities of such series, provided that the
Company may not set a record date for, and the provisions of this paragraph
shall not apply with respect to, the giving or making of any notice,
declaration, request or direction referred to in the next paragraph. If any
record date is set pursuant to this paragraph, the Holders of Outstanding
Securities of the relevant series on such record date, and no other Holders,
shall be entitled to take the relevant action, whether or not such Holders
remain Holders after such record date; provided that no such action shall be
effective hereunder unless taken on or prior to the applicable Expiration Date
by Holders of the requisite principal amount of Outstanding Securities of such
series on such record date. Nothing in this paragraph shall be construed to
prevent the Company from setting a new record date for any action for which a
record date has previously been set pursuant to this paragraph (whereupon the
record date previously set shall automatically and with no action by any Person
be canceled and of no effect), and nothing in this paragraph shall be construed
to render ineffective any action taken by Holders of the requisite principal
amount of Outstanding Securities of the relevant series on the date such action
is taken. Promptly after any record date is set pursuant to this paragraph, the
Company, at its own expense, shall cause notice of such record date, the
proposed


                                                                            -10-
<PAGE>
action by Holders and the applicable Expiration Date to be given to the Trustee
in writing and to each Holder of Securities of the relevant series in the manner
set forth in Section 1.6.

      The Trustee may set any day as a record date for the purpose of
determining the Holders of Outstanding Securities of any series entitled to join
in the giving or making of (i) any Notice of Default, (ii) any declaration of
acceleration referred to in Section 5.2, (iii) any request to institute
proceedings referred to in Section 5.7(2) or (iv) any direction referred to in
Section 5.12, in each case with respect to Securities of such series. If any
record date is set pursuant to this paragraph, the Holders of Outstanding
Securities of such series on such record date, and no other Holders, shall be
entitled to join in such notice, declaration, request or direction, whether or
not such Holders remain Holders after such record date; provided that no such
action shall be effective hereunder unless taken on or prior to the applicable
Expiration Date by Holders of the requisite principal amount of Outstanding
Securities of such series on such record date. Nothing in this paragraph shall
be construed to prevent the Trustee from setting a new record date for any
action for which a record date has previously been set pursuant to this
paragraph (whereupon the record date previously set shall automatically and with
no action by any Person be canceled and of no effect), and nothing in this
paragraph shall be construed to render ineffective any action taken by Holders
of the requisite principal amount of Outstanding Securities of the relevant
series on the date such action is taken. Promptly after any record date is set
pursuant to this paragraph, the Trustee, at the Company's expense, shall cause
notice of such record date, the proposed action by Holders and the applicable
Expiration Date to be given to the Company in writing and to each Holder of
Securities of the relevant series in the manner set forth in Section 1.6.

      With respect to any record date set pursuant to this Section, the party
hereto which sets such record dates may designate any day as the "Expiration
Date" and from time to time may change the Expiration Date to any earlier or
later day; provided that no such change shall be effective unless notice of the
proposed new Expiration Date is given to the other party hereto in writing, and
to each Holder of Securities of the relevant series in the manner set forth in
Section 1.6, on or prior to the existing Expiration Date. If an Expiration Date
is not designated with respect to any record date set pursuant to this Section,
the party hereto which set such record date shall be deemed to have initially
designated the 180th day after such record date as the Expiration Date with
respect thereto, subject to its right to change the Expiration Date as provided
in this paragraph. Notwithstanding the foregoing, no Expiration Date shall be
later than the 180th day after the applicable record date.

      Without limiting the foregoing, a Holder entitled hereunder to take any
action hereunder with regard to any particular Security may do so with regard to
all or any part of the principal amount of such Security or by one or more duly
appointed agents each of which may do so pursuant to such appointment with
regard to all or any part of such principal amount.

SECTION 1.5 NOTICES, ETC., TO TRUSTEE AND COMPANY.

         Any request, demand, authorization, direction, notice, consent, waiver
or Act of Holders or other document provided or permitted by this Indenture to
be made upon, given or furnished to, or filed with,


                                                                            -11-
<PAGE>
            (1)   the Trustee by any Holder or by the Company shall be
      sufficient for every purpose hereunder if made, given, furnished or filed
      in writing (or by facsimile transmissions, provided that oral confirmation
      of receipt shall have been received) to or with the Trustee at its
      Corporate Trust Office, Attention: Corporate Trust Department, or

            (2)   the Company by the Trustee or by any Holder shall be
      sufficient for every purpose hereunder (unless otherwise herein expressly
      provided) if in writing and mailed, first-class postage prepaid,
      personally delivered or sent via overnight courier to the Company
      addressed to it at the address of its principal office specified in the
      first paragraph of this instrument or at any other address previously
      furnished in writing to the Trustee by the Company, Attention: Chief
      Financial Officer.

SECTION 1.6 NOTICE TO HOLDERS; WAIVER.

      Where this Indenture provides for notice to Holders of any event, such
notice shall be sufficiently given (unless otherwise herein expressly provided)
if in writing and mailed, first-class postage prepaid, or delivered by hand or
overnight courier to each Holder affected by such event, at its address as it
appears in the Security Register, not later than the latest date (if any), and
not earlier than the earliest date (if any), prescribed for the giving of such
notice. Neither the failure to mail or deliver by hand or overnight courier any
notice, nor any defect in any notice so mailed or delivered by hand or overnight
courier, to any particular Holder shall affect the sufficiency of such notice
with respect to other Holders. Where this Indenture provides for notice in any
manner, such notice may be waived in writing by the Person entitled to receive
such notice, either before or after the event, and such waiver shall be the
equivalent of such notice. Waivers of notice by Holders shall be filed with the
Trustee, but such filing shall not be a condition precedent to the validity of
any action taken in reliance upon such waiver.

      In case by reason of the suspension of regular mail service or by reason
of any other cause it shall be impracticable to give such notice by mail, then
such notification as shall be made with the approval of the Trustee shall
constitute a sufficient notification for every purpose hereunder.

SECTION 1.7 CONFLICT WITH TRUST INDENTURE ACT.

      If any provision hereof limits, qualifies or conflicts with a provision of
the Trust Indenture Act that is required under the Trust Indenture Act to be a
part of and govern this Indenture, the latter provision shall control. If any
provision of this Indenture modifies or excludes any provision of the Trust
Indenture Act, which may be so modified or excluded, the latter provision shall
be deemed to apply to this Indenture as so modified or to be excluded, as the
case may be.

SECTION 1.8 EFFECT OF HEADINGS AND TABLE OF CONTENTS.

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


                                                                            -12-
<PAGE>
SECTION 1.9 SUCCESSORS AND ASSIGNS.

      All covenants and agreements in this Indenture by the Company shall bind
its successors and assigns, whether so expressed or not.

SECTION 1.10 SEPARABILITY CLAUSE.

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

SECTION 1.11 BENEFITS OF INDENTURE.

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

SECTION 1.12 GOVERNING LAW.

      THIS INDENTURE AND THE SECURITIES SHALL BE GOVERNED BY AND CONSTRUED UNDER
THE LAWS OF THE STATE OF NEW YORK (INCLUDING SECTIONS 5-1401 AND 5-1402 OF THE
GENERAL OBLIGATIONS LAW OF THE STATE OF NEW YORK).

SECTION 1.13 LEGAL HOLIDAYS.

      In any case where any Interest Payment Date, Redemption Date or Stated
Maturity of any Security or the last date on which a Holder has the right to
convert a Security at a particular conversion price shall not be a Business Day
at any Place of Payment, then (notwithstanding any other provision of this
Indenture or of the Securities (other than a provision of any Security which
specifically states that such provision shall apply in lieu of this Section))
payment of interest or principal (and premium, if any) or, if applicable to a
particular series of Securities, conversion need not be made at such Place of
Payment on such date, but may be made on the next succeeding Business Day at
such Place of Payment with the same force and effect as if made on the Interest
Payment Date or Redemption Date, at the Stated Maturity or on such last day for
conversion, as the case may be.

SECTION 1.14 INDENTURE AND SECURITIES SOLELY CORPORATE OBLIGATIONS.

      No recourse for the payment of the principal of or premium, if any, or
interest on any Security, 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
Security, 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


                                                                            -13-
<PAGE>
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
Securities.

SECTION 1.15 INDENTURE MAY BE EXECUTED IN COUNTERPARTS.

      This instrument 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.

                                   ARTICLE 2

                                 SECURITY FORMS

SECTION 2.1 FORMS GENERALLY.

      The Securities of each series shall be in substantially the form set forth
in this Article, or in such other form as shall be established by or pursuant to
a Board Resolution or in one or more indentures supplemental hereto, in each
case with such appropriate insertions, omissions, substitutions and other
variations as are required or permitted by this Indenture, and may have such
letters, numbers or other marks of identification and such legends or
endorsements placed thereon as may be required to comply with the rules of any
securities exchange or Depositary therefor or as may, consistently herewith, be
determined by the officers executing such Securities, as evidenced by their
execution thereof. If the form of Securities of any series is established by
action taken pursuant to a Board Resolution, a copy of an appropriate record of
such action shall be certified by the Secretary or an Assistant Secretary of the
Company and delivered to the Trustee at or prior to the delivery of the Company
Order contemplated by Section 3.3 for the authentication and delivery of such
Securities. Any such Board Resolution or record of such action shall have
attached thereto a true and correct copy of the form of Security referred to
therein approved by or pursuant to such Board Resolution.

      The definitive Securities shall be printed, lithographed or engraved on
steel engraved borders or may be produced in any other manner, all as determined
by the officers executing such Securities, as evidenced by their execution of
such Securities.

SECTION 2.2 FORM OF FACE OF SECURITY.

               [INSERT ANY LEGEND REQUIRED BY THE INTERNAL REVENUE

                      CODE AND THE REGULATIONS THEREUNDER.]

                               CELL GENESYS, INC.

NO.  __________                                                      $__________


                                                                            -14-

<PAGE>
                                                              CUSIP:____________

         _____________________________________________________________

         Cell Genesys, Inc., a corporation duly organized and existing under the
laws of Delaware (herein called the "Company," which term includes any successor
Person under the Indenture hereinafter referred to), for value received, hereby
promises to pay to ____________, or registered assigns, the principal sum of
_____________ dollars on _____________________________ [IF THE SECURITY IS TO
BEAR INTEREST PRIOR TO MATURITY, INSERT -- , and to pay interest thereon from
__________ or from the most recent Interest Payment Date to which interest has
been paid or duly provided for, semi-annually on ___________ and __________ in
each year, commencing _________, at the rate of ___% per annum, until the
principal hereof is paid or made available for payment [IF APPLICABLE, INSERT --
, provided that any principal and premium, and any such installment of interest,
which is overdue shall bear interest at the rate of ___% per annum (to the
extent that the payment of such interest shall be legally enforceable), from the
dates such amounts are due until they are paid or made available for payment,
and such interest shall be payable on demand]. The interest so payable, and
punctually paid or duly provided for, on any Interest Payment Date will, as
provided in such Indenture, be paid to the Person in whose name this Security
(or one or more Predecessor Securities) is registered at the close of business
on the Regular Record Date for such interest, which shall be the ______ or
______ (whether or not a Business Day), as the case may be, next preceding such
Interest Payment Date. Any such interest not so punctually paid or duly provided
for will forthwith cease to be payable to the Holder on such Regular Record Date
and may either be paid to the Person in whose name this Security (or one or more
Predecessor Securities) is registered at the close of business on a Special
Record Date for the payment of such Defaulted Interest to be fixed by the
Trustee, notice whereof shall be given to Holders of Securities of this series
not less than 10 days prior to such Special Record Date, or be paid at any time
in any other lawful manner not inconsistent with the requirements of any
securities exchange on which the Securities of this series may be listed, and
upon such notice as may be required by such exchange, all as more fully provided
in said Indenture].

         [IF THE SECURITY IS NOT TO BEAR INTEREST PRIOR TO MATURITY, INSERT --
The principal of this Security shall not bear interest except in the case of a
default in payment of principal upon acceleration, upon redemption or at Stated
Maturity and in such case the overdue principal and any overdue premium shall
bear interest at the rate of ___% per annum (to the extent that the payment of
such interest shall be legally enforceable), from the dates such amounts are due
until they are paid or made available for payment. Interest on any overdue
principal or premium shall be payable on demand. [Any such interest on overdue
principal or premium which is not paid on demand shall bear interest at the rate
of ___% per annum (to the extent that the payment of such interest on interest
shall be legally enforceable), from the date of such demand until the amount so
demanded is paid or made available for payment. Interest on any overdue interest
shall be payable on demand.]]

         Payment of the principal of (and premium, if any) and [IF APPLICABLE,
INSERT -- any such] interest on this Security will be made at the office or
agency of the Company maintained for that purpose in _______, in such coin or
currency of the United States of America as at the time of

                                                                            -15-
<PAGE>
payment is legal tender for payment of public and private debts [IF APPLICABLE,
INSERT -- ; provided, however, that at the option of the Company payment of
interest may be made by check mailed to the address of the Person entitled
thereto as such address shall appear in the Security Register].

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

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

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

Dated:                                    CELL GENESYS, INC.

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

                                          Title:
                                                 ------------------------------

ATTEST:
       --------------------


SECTION 2.3 FORM OF REVERSE OF SECURITY.

         This Security is one of a duly authorized issue of securities of the
Company (herein called the "Securities"), issued and to be issued in one or more
series under an Indenture, dated as of ________, 200_ (herein called the
"Indenture," which term shall have the meaning assigned to it in such
instrument), between the Company and _____________________________, as Trustee
(herein called the "Trustee," which term includes any successor trustee under
the Indenture), and reference is hereby made to the Indenture and all indentures
supplemental thereto for a statement of the respective rights, limitations of
rights, duties and immunities thereunder of the Company, the Trustee and the
Holders of the Securities and of the terms upon which the Securities are, and
are to be, authenticated and delivered. This Security is one of the series
designated on the face hereof [IF APPLICABLE, INSERT -- , limited in aggregate
principal amount to $________].

         [IF APPLICABLE, INSERT -- The Securities of this series are subject to
redemption upon not less than [if APPLICABLE, INSERT -- 30] days' notice by
mail, [IF APPLICABLE, INSERT-- (1) on __________ in any year commencing with the
year ________ and ending with the year ________ through operation of the sinking
fund for this series at a Redemption Price equal to 100% of the principal
amount, and (2)] at any time [IF APPLICABLE, INSERT-- on or after __________,
20__], as a whole or in part, at the election of the Company, at the following
Redemption Prices (expressed as percentages of the principal amount): If
redeemed [IF APPLICABLE, INSERT-- on or before __________, ___%, and if
redeemed] during the 12-month period beginning ____________ of the years
indicated,


                                                                            -16-
<PAGE>
<TABLE>
<CAPTION>
YEAR                  REDEMPTION PRICE                 YEAR                REDEMPTION PRICE
----                  ----------------                 ----                ----------------
<S>                   <C>                              <C>                 <C>

</TABLE>

and thereafter at a Redemption Price equal to ___% of the principal amount,
together in the case of any such redemption [IF APPLICABLE, INSERT-- (whether
through operation of the sinking fund or otherwise)] with accrued interest to
the Redemption Date, but interest installments whose Stated Maturity is on or
prior to such Redemption Date will be payable to the Holders of such Securities,
or one or more Predecessor Securities, of record at the close of business on the
relevant Record Dates referred to on the face hereof, all as provided in the
Indenture.]

         [IF APPLICABLE, INSERT-- The Securities of this series are subject to
redemption upon not less than [if applicable, insert 30] days' notice by mail,
(1) on __________ in any year commencing with the year _____ and ending with the
year _____ through operation of the sinking fund for this series at the
Redemption Prices for redemption through operation of the sinking fund
(expressed as percentages of the principal amount) set forth in the table below,
and (2) at any time [IF APPLICABLE, INSERT-- on or after __________], as a whole
or in part, at the election of the Company, at the Redemption Prices for
redemption otherwise than through operation of the sinking fund (expressed as
percentages of the principal amount) set forth in the table below: If redeemed
during the 12-month period beginning __________ of the years indicated,

<TABLE>
<CAPTION>

                                          REDEMPTION PRICE FOR                         REDEMPTION PRICE FOR
                                           REDEMPTION THROUGH                    REDEMPTION OTHERWISE THAN THROUGH
                                            OPERATION OF THE                             OPERATION OF THE
            YEAR                              SINKING FUND                                 SINKING FUND
            ----                              ------------                                 ------------
<S>                                       <C>                                    <C>

</TABLE>

and thereafter at a Redemption Price equal to ____% of the principal amount,
together in the case of any such redemption (whether through operation of the
sinking fund or otherwise) with accrued interest to the Redemption Date, but
interest installments whose Stated Maturity is on or prior to such Redemption
Date will be payable to the Holders of such Securities, or one or more
Predecessor Securities, of record at the close of business on the relevant
Record Dates referred to on the face hereof, all as provided in the Indenture.]

         [IF APPLICABLE, INSERT -- Notwithstanding the foregoing, the Company
may not, prior to __________, redeem any Securities of this series as
contemplated by [IF APPLICABLE, INSERT-- clause (2) of] the preceding paragraph
as a part of, or in anticipation of, any refunding operation by the application,
directly or indirectly, of moneys borrowed having an interest cost to the
Company (calculated in accordance with generally accepted financial practice) of
less than ___% per annum.]


                                                                            -17-
<PAGE>
         [IF APPLICABLE, INSERT-- The sinking fund for this series provides for
the redemption on __________ in each year beginning with the year ______ and
ending with the year ______ of [IF APPLICABLE, INSERT-- not less than $_______
("mandatory sinking fund") and not more than] $_______ aggregate principal
amount of Securities of this series. Securities of this series acquired or
redeemed by the Company otherwise than through [IF APPLICABLE, INSERT--
mandatory] sinking fund payments may be credited against subsequent [IF
APPLICABLE, INSERT -- mandatory] sinking fund payments otherwise required to be
made [IF APPLICABLE, INSERT-- , in the inverse order in which they become due].]

         [IF THE SECURITY IS SUBJECT TO REDEMPTION OF ANY KIND, INSERT -- In the
event of redemption of this Security in part only, a new Security or Securities
of this series and of like tenor for the unredeemed portion hereof will be
issued in the name of the Holder hereof upon the cancellation hereof.]

         [IF APPLICABLE, INSERT-- The Indenture contains provisions for
defeasance at any time of [the entire indebtedness of this Security] [or]
[certain restrictive covenants and Events of Default with respect to this
Security] [, in each case] upon compliance with certain conditions set forth in
the Indenture.]

         [IF THE SECURITY IS CONVERTIBLE INTO COMMON STOCK OF THE COMPANY,
INSERT-- Subject to the provisions of the Indenture, the Holder of this Security
is entitled, at its option, at any time on or before [insert date] (except that,
in case this Security or any portion hereof shall be called for redemption, such
right shall terminate with respect to this Security or portion hereof, as the
case may be, so called for redemption at the close of business on the first
Business Day next preceding the date fixed for redemption as provided in the
Indenture unless the Company defaults in making the payment due upon
redemption), to convert the principal amount of this Security (or any portion
hereof which is $1,000 or an integral multiple thereof), into fully paid and
non-assessable shares (calculated as to each conversion to the nearest 1/100th
of a share) of the Common Stock of the Company, as said shares shall be
constituted at the date of conversion, at the conversion price of $______
principal amount of Securities for each share of Common Stock, or at the
adjusted conversion price in effect at the date of conversion determined as
provided in the Indenture, upon surrender of this Security, together with the
conversion notice hereon duly executed, to the Company at the designated office
or agency of the Company in __________, accompanied (if so required by the
Company) by instruments of transfer, in form satisfactory to the Company and to
the Trustee, duly executed by the Holder or by its duly authorized attorney in
writing. Such surrender shall, if made during any period beginning at the close
of business on a Regular Record Date and ending at the opening of business on
the Interest Payment Date next following such Regular Record Date (unless this
Security or the portion being converted shall have been called for redemption on
a Redemption Date during the period beginning at the close of business on a
Regular Record Date and ending at the opening of business on the first Business
Day after the next succeeding Interest Payment Date, or if such Interest Payment
Date is not a Business Day, the second such Business Day), also be accompanied
by payment in funds acceptable to the Company of an amount equal to the interest
payable on such Interest Payment Date on the principal amount of this Security
then being converted. Subject to the aforesaid requirement for payment and, in
the case of a conversion

                                                                            -18-
<PAGE>
after the Regular Record Date next preceding any Interest Payment Date and on or
before such Interest Payment Date, to the right of the Holder of this Security
(or any Predecessor Security) of record at such Regular Record Date to receive
an installment of interest (with certain exceptions provided in the Indenture),
no adjustment is to be made on conversion for interest accrued hereon or for
dividends on shares of Common Stock issued on conversion. The Company is not
required to issue fractional shares upon any such conversion, but shall make
adjustment therefor in cash on the basis of the current market value of such
fractional interest as provided in the Indenture. The conversion price is
subject to adjustment as provided in the Indenture. In addition, the Indenture
provides that in case of certain consolidations or mergers to which the Company
is a party or the sale of substantially all of the assets of the Company, the
Indenture shall be amended, without the consent of any Holders of Securities, so
that this Security, if then outstanding, will be convertible thereafter, during
the period this Security shall be convertible as specified above, only into the
kind and amount of securities, cash and other property receivable upon the
consolidation, merger or sale by a holder of the number of shares of Common
Stock into which this Security might have been converted immediately prior to
such consolidation, merger or sale (assuming such holder of Common Stock failed
to exercise any rights of election and received per share the kind and amount
received per share by a plurality of non-electing shares). In the event of
conversion of this Security in part only, a new Security or Securities for the
unconverted portion hereof shall be issued in the name of the Holder hereof upon
the cancellation hereof.]

         [IF THE SECURITY IS CONVERTIBLE INTO OTHER SECURITIES OF THE COMPANY,
SPECIFY THE CONVERSION FEATURES.]

         [IF THE SECURITY IS NOT AN ORIGINAL ISSUE DISCOUNT SECURITY, INSERT --
If an Event of Default with respect to Securities of this series shall occur and
be continuing, the principal of the Securities of this series may be declared
due and payable in the manner and with the effect provided in the Indenture.]

         [IF THE SECURITY IS AN ORIGINAL ISSUE DISCOUNT SECURITY, INSERT -- If
an Event of Default with respect to Securities of this series shall occur and be
continuing, an amount of principal of the Securities of this series may be
declared due and payable in the manner and with the effect provided in the
Indenture. Such amount shall be equal to -- INSERT FORMULA FOR DETERMINING THE
AMOUNT. Upon payment (i) of the amount of principal so declared due and payable
and (ii) of interest on any overdue principal, premium and interest (in each
case to the extent that the payment of such interest shall be legally
enforceable), all of the Company's obligations in respect of the payment of the
principal of and premium and interest, if any, on the Securities of this series
shall terminate.]

         The Indenture permits, with certain exceptions as therein provided, the
amendment thereof and the modification of the rights and obligations of the
Company and the rights of the Holders of the Securities of each series to be
affected under the Indenture at any time by the Company and the Trustee with the
consent of the Holders of more than 50% in principal amount of the Securities at
the time Outstanding of each series to be affected. The Indenture also contains
provisions permitting the Holders of specified percentages in principal amount
of the Securities of each series at the time Outstanding, on behalf of the
Holders of all Securities of such series, to waive compliance by the

                                                                            -19-
<PAGE>
Company with certain provisions of the Indenture and certain past defaults under
the Indenture and their consequences. Any such consent or waiver by the Holder
of this Security shall be conclusive and binding upon such Holder and upon all
future Holders of this Security and of any Security issued upon the registration
of transfer hereof or in exchange herefor or in lieu hereof, whether or not
notation of such consent or waiver is made upon this Security.

         As provided in and subject to the provisions of the Indenture, the
Holder of this Security shall not have the right to institute any proceeding
with respect to the Indenture or for the appointment of a receiver or trustee or
for any other remedy thereunder, unless such Holder shall have previously given
the Trustee written notice of a continuing Event of Default with respect to the
Securities of this series, the Holders of not less than a majority in principal
amount of the Securities of this series at the time Outstanding shall have made
written request to the Trustee to institute proceedings in respect of such Event
of Default as Trustee and offered the Trustee reasonable indemnity, and the
Trustee shall not have received from the Holders of a majority in principal
amount of Securities of this series at the time Outstanding a direction
inconsistent with such request, and shall have failed to institute any such
proceeding, for 60 days after receipt of such notice, request and offer of
indemnity. The foregoing shall not apply to any suit instituted by the Holder of
this Security for the enforcement of any payment of principal hereof or any
premium or interest hereon on or after the respective due dates expressed
herein.

         No reference herein to the Indenture and no provision of this Security
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 on this Security at the times, place and rate, and in the coin or
currency, herein prescribed.

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

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

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


                                                                            -20-
<PAGE>
         Prior to due presentment of this Security for registration of transfer,
the Company, the Trustee and any agent of the Company or the Trustee may treat
the Person in whose name this Security is registered as the owner hereof for all
purposes, whether or not this Security be overdue, and neither the Company, the
Trustee nor any such agent shall be affected by notice to the contrary.

         All terms used in this Security that are defined in the Indenture shall
have the meanings assigned to them in the Indenture.

SECTION 2.4 FORM OF LEGEND FOR GLOBAL SECURITIES.

         Unless otherwise specified as contemplated by Section 3.1 for the
Securities evidenced thereby, every Global Security authenticated and delivered
hereunder shall bear a legend in substantially the following form:

THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE
HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITARY OR A
NOMINEE THEREOF. THIS SECURITY MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR A
SECURITY REGISTERED, AND NO TRANSFER OF THIS SECURITY IN WHOLE OR IN PART MAY BE
REGISTERED, IN THE NAME OF ANY PERSON OTHER THAN SUCH DEPOSITARY OR A NOMINEE
THEREOF, EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE.

SECTION 2.5 FORM OF TRUSTEE'S CERTIFICATE OF AUTHENTICATION.

         The Trustee's certificates of authentication shall be in substantially
the following form:

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

                                  -------------------------------,
                                  as Trustee

                                  By:
                                      ---------------------------------
                                      Authorized Officer

SECTION 2.6 FORM OF CONVERSION NOTICE.

         Conversion notices shall be in substantially the following form:
To Cell Genesys, Inc.:

         The undersigned owner of this Security hereby irrevocably exercises the
option to convert this Security, or portion hereof (which is $1,000 or an
integral multiple thereof) below designated, into shares of Common Stock of the
Company in accordance with the terms of the Indenture referred to in this
Security, and directs that the shares issuable and deliverable upon the
conversion, together

                                                                            -21-
<PAGE>
with any check in payment for fractional shares and any Securities representing
any unconverted principal amount hereof, be issued and delivered to the
registered holder hereof unless a different name has been indicated below. If
this Notice is being delivered on a date after the close of business on a
Regular Record Date and prior to the opening of business on the related Interest
Payment Date (unless this Security or the portion thereof being converted has
been called for redemption on a Redemption Date during the period beginning at
the close of business on a Regular Record Date and ending at the opening of
business on the first Business Day after the next succeeding Interest Payment
Date, or if such Interest Payment Date is not a Business Day, the second such
Business Day), this Notice is accompanied by payment, in funds acceptable to the
Company, of an amount equal to the interest payable on such Interest Payment
Date of the principal of this Security to be converted. If shares are to be
issued in the name of a person other than the undersigned, the undersigned will
pay all transfer taxes payable with respect hereto. Any amount required to be
paid by the undersigned on account of interest accompanies this Security.

         Principal Amount to be Converted
(in an integral multiple of $1,000, if less than all)

         U.S. $

Dated:

                                            Signature(s) must be guaranteed by
                                            an eligible guarantor institution
                                            (banks, stockbrokers, savings and
                                            loan associations and credit unions
                                            with membership in an approved
                                            signature guarantee medallion
                                            program) pursuant to Securities and
                                            Exchange Commission Rule 17Ad-15.


                                            ------------------------------------
                                            Signature Guaranty

         Fill in for registration of shares of Common Stock and Security if to
be issued otherwise than to the registered Holder.


-------------------------------------       ------------------------------------
(Name)                                       Social Security or Other Taxpayer
                                             Identification Number

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



-------------------------------------
Please print Name and Address
(including zip code)


                                                                            -22-
<PAGE>
[The above conversion notice is to be modified, as appropriate, for conversion
into other securities or property of the Company.]


                                                                            -23-
<PAGE>
                                   ARTICLE 3

                                 THE SECURITIES

SECTION 3.1 AMOUNT UNLIMITED; ISSUABLE IN SERIES.

         The aggregate principal amount of Securities that may be authenticated
and delivered under this Indenture is unlimited.

         The Securities may be issued in one or more series. There shall be
established in or pursuant to a Board Resolution and, subject to Section 3.3,
set forth, or determined in the manner provided, in an Officers' Certificate, or
established in one or more indentures supplemental hereto, prior to the issuance
of Securities of any series,

                  (1) the title of the Securities of the series (which shall
         distinguish the Securities of the series from Securities of any other
         series);

                  (2) any limit upon the aggregate principal amount of the
         Securities of the series which may be authenticated and delivered under
         this Indenture (except for Securities authenticated and delivered upon
         registration of transfer of, or in exchange for, or in lieu of, other
         Securities of the series pursuant to Section 3.4, 3.5, 3.6, 9.6 or 11.7
         and except for any Securities which, pursuant to Section 3.3, are
         deemed never to have been authenticated and delivered hereunder);

                  (3) the Person to whom any interest on a Security of the
         series shall be payable, if other than the Person in whose name that
         Security (or one or more Predecessor Securities) is registered at the
         close of business on the Regular Record Date for such interest;

                  (4) the date or dates on which the principal of any Securities
         of the series is payable;

                  (5) the rate or rates (which may be fixed or variable) at
         which any Securities of the series shall bear interest, if any, the
         date or dates from which any such interest shall accrue, the Interest
         Payment Dates on which any such interest shall be payable and the
         Regular Record Date for any such interest payable on any Interest
         Payment Date (or the method for determining the dates and rates);

                  (6) the place or places where the principal of and any premium
         and interest on any Securities of the series shall be payable;

                  (7) the period or periods within which, the price or prices at
         which and the terms and conditions upon which any Securities of the
         series may be redeemed, in whole or in part,

                                                                            -24-
<PAGE>
         at the option of the Company and, if other than by a Board Resolution,
         the manner in which any election by the Company to redeem the
         Securities shall be evidenced;

                  (8) the obligation, if any, of the Company to redeem or
         purchase any Securities of the series pursuant to any sinking fund or
         analogous provisions or at the option of the Holder thereof and the
         period or periods within which, the price or prices at which and the
         terms and conditions upon which any Securities of the series shall be
         redeemed or purchased, in whole or in part, pursuant to such
         obligation;

                  (9) if other than denominations of $1,000 and any integral
         multiple thereof, the denominations in which any Securities of the
         series shall be issuable;

                  (10) if the amount of principal of or any premium or interest
         on any Securities of the series may be determined with reference to an
         index or pursuant to a formula, the manner in which such amounts shall
         be determined;

                  (11) if other than the currency of the United States of
         America, the currency, currencies or currency units in which the
         principal of or any premium or interest on any Securities of the series
         shall be payable and the manner of determining the equivalent thereof
         in the currency of the United States of America for any purpose,
         including for purposes of the definition of "Outstanding" in Section
         1.1;

                  (12) if the principal of or any premium or interest on any
         Securities of the series is to be payable, at the election of the
         Company or the Holder thereof, in one or more currencies or currency
         units other than that or those in which such Securities are stated to
         be payable, the currency, currencies or currency units in which the
         principal of or any premium or interest on such Securities as to which
         such election is made shall be payable, the periods within which and
         the terms and conditions upon which such election is to be made and the
         amount so payable (or the manner in which such amount shall be
         determined);

                  (13) if other than the entire principal amount thereof, the
         portion of the principal amount of any Securities of the series which
         shall be payable upon declaration of acceleration of the Maturity
         thereof pursuant to Section 5.2;

                  (14) if the principal amount payable at the Stated Maturity of
         any Securities of the series will not be determinable as of any one or
         more dates prior to the Stated Maturity, the amount which shall be
         deemed to be the principal amount of such Securities as of any such
         date for any purpose thereunder or hereunder, including the principal
         amount thereof which shall be due and payable upon any Maturity other
         than the Stated Maturity or which shall be deemed to be Outstanding as
         of any date prior to the Stated Maturity (or, in any such case, the
         manner in which such amount deemed to be the principal amount shall be
         determined);

                  (15) if applicable, that the Securities of the series, in
         whole or any specified part, shall be defeasible pursuant to Section
         13.2 or Section 13.3 or both such Sections, or any other defeasance
         provisions applicable to any Securities of the series, and, if other
         than by a

                                                                            -25-
<PAGE>
         Board Resolution, the manner in which any election by the Company to
         defease such Securities shall be evidenced;

                  (16) if applicable, the terms of any right to convert or
         exchange Securities of the series into shares of Common Stock of the
         Company or other securities or property;

                  (17) if applicable, that any Securities of the series shall be
         issuable in whole or in part in the form of one or more Global
         Securities and, in such case, the respective Depositaries for such
         Global Securities, the form of any legend or legends which shall be
         borne by any such Global Security in addition to or in lieu of that set
         forth in Section 2.4 and any circumstances in addition to or in lieu of
         those set forth in clause (2) of the last paragraph of Section 3.5 in
         which any such Global Security may be exchanged in whole or in part for
         Securities registered, and any transfer of such Global Security in
         whole or in part may be registered, in the name or names of Persons
         other than the Depositary for such Global Security or a nominee
         thereof;

                  (18) any addition to or change in the Events of Default which
         applies to any Securities of the series and any change in the right of
         the Trustee or the requisite Holders of such Securities to declare the
         principal amount thereof due and payable pursuant to Section 5.2;

                  (19) any addition to or change in the covenants set forth in
         Article 10 which applies to Securities of the series;

                  (20) any Authenticating Agents, Paying Agents, Security
         Registrars or such other agents necessary in connection with the
         issuance of the Securities of such series, including, without
         limitation, exchange rate agents and calculation agents;

                  (21) if applicable, the terms of any security that will be
         provided for a series of Securities, including any provisions regarding
         the circumstances under which collateral may be released or
         substituted;

                  (22) if applicable, the terms of any guaranties for the
         Securities and any circumstances under which there may be additional
         obligors on the Securities; and

                  (23) any other terms of the series (which terms shall not be
         inconsistent with the provisions of this Indenture, except as permitted
         by Section 9.1(5)).

         All Securities of any one series shall be substantially identical
except as to denomination and except as may otherwise be provided in or pursuant
to the Board Resolution referred to above and (subject to Section 3.3) set
forth, or determined in the manner provided, in the Officers' Certificate
referred to above or in any such indenture supplemental hereto.

         If any of the terms of the series are established by action taken
pursuant to a Board Resolution, a copy of an appropriate record of such action
shall be certified by the Secretary or an

                                                                            -26-
<PAGE>
Assistant Secretary of the Company and delivered to the Trustee at or prior to
the delivery of the Officers' Certificate setting forth the terms of the series.

SECTION 3.2 DENOMINATIONS.

         The Securities of each series shall be issuable only in registered form
without coupons and only in such denominations as shall be specified as
contemplated by Section 3.1. In the absence of any such specified denomination
with respect to the Securities of any series, the Securities of such series
shall be issuable in denominations of $1,000 and any integral multiple thereof.

SECTION 3.3 EXECUTION, AUTHENTICATION, DELIVERY AND DATING.

         The Securities shall be executed on behalf of the Company by its
Chairman of the Board, its Vice Chairman of the Board, its Chief Executive
Officer, its principal financial officer, its President or one of its Vice
Presidents, attested by its Treasurer, its Secretary or one of its Assistant
Treasurers or Assistant Secretaries. The signature of any of these officers on
the Securities may be manual or facsimile.

         Securities bearing the manual or facsimile signatures of individuals
who were at any time the proper officers of the Company shall bind the Company,
notwithstanding that such individuals or any of them have ceased to hold such
offices prior to the authentication and delivery of such Securities or did not
hold such offices at the date of such Securities.

         At any time and from time to time after the execution and delivery of
this Indenture, the Company may deliver Securities of any series executed by the
Company to the Trustee for authentication, together with a Company Order for the
authentication and delivery of such Securities, and the Trustee in accordance
with the Company Order shall authenticate and deliver such Securities. If the
form or terms of the Securities of the series have been established by or
pursuant to one or more Board Resolutions as permitted by Sections 2.1 and 3.1,
in authenticating such Securities, and accepting the additional responsibilities
under this Indenture in relation to such Securities, the Trustee shall be
entitled to receive, and (subject to Section 6.1) shall be fully protected in
relying upon, a copy of such Board Resolution, the Officers' Certificate setting
forth the terms of the series and an Opinion of Counsel, with such Opinion of
Counsel stating,

                  (1) if the form of such Securities has been established by or
         pursuant to Board Resolution as permitted by Section 2.1, that such
         form has been established in conformity with the provisions of this
         Indenture;

                  (2) if the terms of such Securities have been established by
         or pursuant to Board Resolution as permitted by Section 3.1, that such
         terms have been established in conformity with the provisions of this
         Indenture; and

                  (3) that such Securities, when authenticated and delivered by
         the Trustee and issued by the Company in the manner and subject to any
         conditions specified in such Opinion of Counsel, will constitute valid
         and legally binding obligations of the Company

                                                                            -27-
<PAGE>
         enforceable in accordance with their terms, subject to bankruptcy,
         insolvency, fraudulent transfer, reorganization, moratorium and similar
         laws of general applicability relating to or affecting creditors'
         rights and to general equity principles.

         If such form or terms have been so established, the Trustee shall not
be required to authenticate such Securities if the issue of such Securities
pursuant to this Indenture will affect the Trustee's own rights, duties or
immunities under the Securities and this Indenture or otherwise in a manner
which is not reasonably acceptable to the Trustee.

         Notwithstanding the provisions of Section 3.1 and of the preceding
paragraph, if all Securities of a series are not to be originally issued at one
time, it shall not be necessary to deliver the Officers' Certificate otherwise
required pursuant to Section 3.1 or the Company Order and Opinion of Counsel
otherwise required pursuant to such preceding paragraph at or prior to the
authentication of each Security of such series if such documents are delivered
at or prior to the authentication upon original issuance of the first Security
of such series to be issued.

         Each Security shall be dated the date of its authentication.

         No Security shall be entitled to any benefit under this Indenture or be
valid or obligatory for any purpose unless there appears on such Security a
certificate of authentication substantially in the form provided for herein
executed by the Trustee by manual signature, and such certificate upon any
Security shall be conclusive evidence, and the only evidence, that such Security
has been duly authenticated and delivered hereunder. Notwithstanding the
foregoing, if any Security shall have been authenticated and delivered hereunder
but never issued and sold by the Company, and the Company shall deliver such
Security to the Trustee for cancellation as provided in Section 3.9, for all
purposes of this Indenture such Security shall be deemed never to have been
authenticated and delivered hereunder and shall never be entitled to the
benefits of this Indenture.

         Neither the Company nor the Trustee shall have any responsibility for
any defect in the CUSIP number that appears on any Security, check, advice of
payment or redemption notice, and any such document may contain a statement to
the effect that CUSIP numbers have been assigned by an independent service for
convenience of reference and that neither the Company nor the Trustee shall be
liable for any inaccuracy in such numbers.

SECTION 3.4 TEMPORARY SECURITIES.

         Pending the preparation of definitive Securities of any series, the
Company may execute, and upon Company Order the Trustee shall authenticate and
deliver, temporary Securities which are printed, lithographed, typewritten,
mimeographed or otherwise produced, in any authorized denomination,
substantially of the tenor of the definitive Securities in lieu of which they
are issued and with such appropriate insertions, omissions, substitutions and
other variations as the officers executing such Securities may determine, as
evidenced by their execution of such Securities.

         If temporary Securities of any series are issued, the Company will
cause definitive Securities of that series to be prepared without unreasonable
delay. After the preparation of definitive

                                                                            -28-
<PAGE>
Securities of such series, the temporary Securities of such series shall be
exchangeable for definitive Securities of such series upon surrender of the
temporary Securities of such series at the office or agency of the Company in a
Place of Payment for that series, without charge to the Holder. Upon surrender
for cancellation of any one or more temporary Securities of any series, the
Company shall execute and the Trustee shall authenticate and deliver in exchange
therefor one or more definitive Securities of the same series, of any authorized
denominations and of like tenor and aggregate principal amount. Until so
exchanged, the temporary Securities of any series shall in all respects be
entitled to the same benefits under this Indenture as definitive Securities of
such series and tenor.

SECTION 3.5 REGISTRATION; REGISTRATION OF TRANSFER AND EXCHANGE.

         The Company shall cause to be kept at the Corporate Trust Office of the
Trustee a register (the register maintained in such office and in any other
office or agency of the Company in a Place of Payment being herein sometimes
collectively referred to as the "Security Register") in which, subject to such
reasonable regulations as it may prescribe, the Company shall provide for the
registration of Securities and of transfers of Securities. The Trustee is hereby
appointed "Security Registrar" for the purpose of registering Securities and
transfers of Securities as herein provided.

         Upon surrender for registration of transfer of any Security of a series
at the office or agency of the Company in a Place of Payment for that series,
the Company shall execute, and the Trustee shall authenticate and deliver, in
the name of the designated transferee or transferees, one or more new Securities
of the same series, of any authorized denominations and of like tenor and
aggregate principal amount.

         At the option of the Holder, Securities of any series may be exchanged
for other Securities of the same series, of any authorized denominations and of
like tenor and aggregate principal amount, upon surrender of the Securities to
be exchanged at such office or agency. Whenever any Securities are so
surrendered for exchange, the Company shall execute, and the Trustee shall
authenticate and deliver, the Securities that the Holder making the exchange is
entitled to receive.

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

         Every Security presented or surrendered for registration of transfer or
for exchange shall (if so required by the Company or the Trustee) be duly
endorsed, or be accompanied by a written instrument of transfer in form
satisfactory to the Company and the Security Registrar duly executed, by the
Holder thereof or its attorney duly authorized in writing.

         No service charge shall be made for any registration of transfer or
exchange of Securities, but the Company may require payment of a sum sufficient
to cover any tax or other governmental charge that may be imposed in connection
with any registration of transfer or exchange of Securities, other than
exchanges pursuant to Section 3.4, 9.6 or 11.7 not involving any transfer.


                                                                            -29-
<PAGE>
         If the Securities of any series (or of any series and specified tenor)
are to be redeemed in part, the Company shall not be required (A) to issue,
register the transfer of or exchange any Securities of that series (or of that
series and specified tenor, as the case may be) during a period beginning at the
opening of business 15 days before the day of the mailing of a notice of
redemption of any such Securities selected for redemption under Section 11.3 and
ending at the close of business on the day of such mailing, or (B) to register
the transfer of or exchange any Security so selected for redemption in whole or
in part, except the unredeemed portion of any Security being redeemed in part.

         The provisions of clauses (1), (2), (3) and (4) below shall apply only
to Global Securities:

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

                  (2) Notwithstanding any other provision in this Indenture, no
         Global Security may be exchanged in whole or in part for Securities
         registered, and no transfer of a Global Security in whole or in part
         may be registered, in the name of any Person other than the Depositary
         for such Global Security or a nominee thereof unless (A) such
         Depositary (i) has notified the Company that it is unwilling or unable
         to continue as Depositary for such Global Security or (ii) has ceased
         to be a clearing agency registered under the Exchange Act, (B) there
         shall have occurred and be continuing an Event of Default with respect
         to such Global Security or (C) there shall exist such circumstances, if
         any, in addition to or in lieu of the foregoing as have been specified
         for this purpose as contemplated by Section 3.1.

                  (3) Subject to clause (2) above, any exchange of a Global
         Security for other Securities may be made in whole or in part, and all
         Securities issued in exchange for a Global Security or any portion
         thereof shall be registered in such names as the Depositary for such
         Global Security shall direct.

                  (4) Every Security authenticated and delivered upon
         registration of transfer of, or in exchange for or in lieu of, a Global
         Security or any portion thereof, whether pursuant to this Section,
         Section 3.4, 3.6, 9.6 or 11.7 or otherwise, shall be authenticated and
         delivered in the form of, and shall be, a Global Security, unless such
         Security is registered in the name of a Person other than the
         Depositary for such Global Security or a nominee thereof.

SECTION 3.6 MUTILATED, DESTROYED, LOST AND STOLEN SECURITIES.

         If any mutilated Security is surrendered to the Trustee, the Company
shall execute and the Trustee shall authenticate and deliver in exchange
therefor a new Security of the same series and of like tenor and principal
amount and bearing a number not contemporaneously outstanding.

         If there shall be delivered to the Company and the Trustee (i) evidence
to their satisfaction of the destruction, loss or theft of any Security and (ii)
such security or indemnity as may be required by them to save each of them and
any agent of either of them harmless, then, in the absence of notice

                                                                            -30-
<PAGE>
to the Company or the Trustee that such Security has been acquired by a bona
fide purchaser, the Company shall execute and the Trustee shall authenticate and
deliver, in lieu of any such destroyed, lost or stolen Security, a new Security
of the same series and of like tenor and principal amount and bearing a number
not contemporaneously outstanding.

         In case any such mutilated, destroyed, lost or stolen Security has
become or is about to become due and payable, the Company in its discretion may,
instead of issuing a new Security, pay such Security.

         Upon the issuance of any new Security under this Section, the Company
may require the payment of a sum sufficient to cover any tax or other
governmental charge that may be imposed in relation thereto and any other
expenses (including the fees and expenses of the Trustee) connected therewith.

         Every new Security of any series issued pursuant to this Section in
lieu of any destroyed, lost or stolen Security shall constitute an original
additional contractual obligation of the Company, whether or not the destroyed,
lost or stolen Security shall be at any time enforceable by anyone, and shall be
entitled to all the benefits of this Indenture equally and proportionately with
any and all other Securities of that series duly issued hereunder.

         The provisions of this Section are exclusive and shall preclude (to the
extent lawful) all other rights and remedies with respect to the replacement or
payment of mutilated, destroyed, lost or stolen Securities.

SECTION 3.7 PAYMENT OF INTEREST; INTEREST RIGHTS PRESERVED.

         Except as otherwise provided as contemplated by Section 3.1 with
respect to any series of Securities, interest on any Security which is payable,
and is punctually paid or duly provided for, on any Interest Payment Date shall
be paid to the Person in whose name that Security (or one or more Predecessor
Securities) is registered at the close of business on the Regular Record Date
for such interest.

         Any interest on any Security of any series which is payable, but is not
punctually paid or duly provided for, on any Interest Payment Date (herein
called "Defaulted Interest") shall forthwith cease to be payable to the Holder
on the relevant Regular Record Date by virtue of having been such Holder, and
such Defaulted Interest may 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 Securities of such series
         (or their respective Predecessor Securities) 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 proposed to be paid on each Security of such series and the
         date of the proposed payment, and at the same time the Company shall
         deposit with the Trustee an amount of money equal to the aggregate
         amount

                                                                            -31-
<PAGE>
         proposed 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 Persons entitled to such Defaulted
         Interest as in this clause provided. Thereupon the Trustee shall fix a
         Special Record Date for the payment of such Defaulted Interest, which
         shall be not more than 15 days and not less than 10 days prior to the
         date of the proposed payment and not less than 10 days after the
         receipt by the Trustee of the notice of the proposed payment. The
         Trustee shall promptly notify the Company of such Special Record Date
         and, in the name and at the expense of the Company, shall cause notice
         of the proposed payment of such Defaulted Interest and the Special
         Record Date therefor to be given to each Holder of Securities of such
         series in the manner set forth in Section 1.6, not less than 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 Securities of such series (or their respective
         Predecessor Securities) are registered at the close of business on such
         Special Record Date and shall no longer be payable pursuant to the
         following clause (2).

                  (2) The Company may make payment of any Defaulted Interest on
         the Securities of any series in any other lawful manner not
         inconsistent with the requirements of any securities exchange on which
         such Securities may be listed, and upon such notice as may be required
         by such exchange, 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.

         Subject to the foregoing provisions of this Section, each Security
delivered under this Indenture upon registration of transfer of or in exchange
for or in lieu of any other Security shall carry the rights to interest accrued
and unpaid, and to accrue, which were carried by such other Security.

         Subject to the provisions of Section 14.2, in the case of any Security
(or any part thereof) which is converted after any Regular Record Date and on or
prior to the next succeeding Interest Payment Date (other than any Security the
principal of (or premium, if any, on) which shall become due and payable,
whether at Stated Maturity or by declaration of acceleration or otherwise prior
to such Interest Payment Date), interest whose Stated Maturity is on such
Interest Payment Date shall be payable on such Interest Payment Date
notwithstanding such conversion and such interest (whether or not punctually
paid or duly provided for) shall be paid to the Person in whose name that
Security (or any one or more Predecessor Securities) is registered at the close
of business on such Regular Record Date. Except as otherwise expressly provided
in the immediately preceding sentence or in Section 14.2, in the case of any
Security (or any part thereof) which is converted, interest whose Stated
Maturity is after the date of conversion of such Security (or such part thereof)
shall not be payable.


                                                                            -32-
<PAGE>
SECTION 3.8 PERSONS DEEMED OWNERS.

         Prior to due presentment of a Security for registration of transfer,
the Company, the Trustee and any agent of the Company or the Trustee may treat
the Person in whose name such Security is registered as the owner of such
Security for the purpose of receiving payment of principal of and any premium
and (subject to Section 3.7) any interest on such Security and for all other
purposes whatsoever, whether or not such Security be overdue, and neither the
Company, the Trustee nor any agent of the Company or the Trustee shall be
affected by notice to the contrary.

SECTION 3.9 CANCELLATION.

         All Securities surrendered for payment, redemption, registration of
transfer or exchange or for credit against any sinking fund payment shall, if
surrendered to any Person other than the Trustee, be delivered to the Trustee
and shall be promptly canceled by it. The Company may at any time deliver to the
Trustee for cancellation any Securities previously authenticated and delivered
hereunder which the Company may have acquired in any manner whatsoever, and may
deliver to the Trustee (or to any other Person for delivery to the Trustee) for
cancellation any Securities previously authenticated hereunder which the Company
has not issued and sold, and all Securities so delivered shall be promptly
canceled by the Trustee. No Securities shall be authenticated in lieu of or in
exchange for any Securities canceled as provided in this Section, except as
expressly permitted by this Indenture. All canceled Securities held by the
Trustee shall be disposed of in accordance with its customary procedures.

SECTION 3.10 COMPUTATION OF INTEREST.

         Except as otherwise specified as contemplated by Section 3.1 for
Securities of any series, interest on the Securities of each series shall be
computed on the basis of a 360-day year of twelve 30-day months.

                                   ARTICLE 4

                           SATISFACTION AND DISCHARGE

SECTION 4.1 SATISFACTION AND DISCHARGE OF INDENTURE.

         This Indenture shall upon Company Request cease to be of further effect
(except as to any surviving rights of registration of transfer or exchange of
Securities herein expressly provided for), and the Trustee, at the expense of
the Company, shall execute proper instruments acknowledging satisfaction and
discharge of this Indenture, when

                  (1) either


                        (A) all Securities theretofore authenticated and
delivered (other than (i) Securities which have been destroyed, lost or stolen
and which have been replaced or paid as

                                                                            -33-
<PAGE>
provided in Section 3.6 and (ii) Securities for whose payment money has
theretofore been deposited in trust or segregated and held in trust by the
Trustee or the Company and thereafter repaid to the Company or discharged from
such trust, as provided in Section 10.3) have been delivered to the Trustee for
cancellation; or

                        (B) all such Securities not theretofore delivered to the
Trustee for cancellation

                              (i) have become due and payable, or

                              (ii) will become due and payable at their Stated
Maturity within one year, or

                              (iii) are to be called for redemption within one
year under arrangements satisfactory to the Trustee for the giving of notice of
redemption by the Trustee in the name, and at the expense, of the Company,

and the Company, in the case of (i), (ii) or (iii) above, has deposited or
caused to be deposited with the Trustee as trust funds in trust for the purpose
money in an amount sufficient to pay and discharge the entire indebtedness on
such Securities not theretofore delivered to the Trustee for cancellation, for
principal and any premium and interest to the date of such deposit (in the case
of Securities which have become due and payable) or to the Stated Maturity or
Redemption Date, as the case may be;

                  (2) the Company has paid or caused to be paid all other sums
payable hereunder by the Company; and

                  (3) the Company has delivered to the Trustee an Officers'
Certificate and an Opinion of Counsel, each stating that all conditions
precedent herein provided for relating to the satisfaction and discharge of this
Indenture have been complied with.

         Notwithstanding the satisfaction and discharge of this Indenture, the
obligations of the Company to the Trustee under Section 6.7, the obligations of
the Trustee to any Authenticating Agent under Section 6.14 and, if money shall
have been deposited with the Trustee pursuant to subclause (B) of clause (1) of
this Section, the obligations of the Trustee under Section 4.2 and the last
paragraph of Section 10.3 shall survive.

SECTION 4.2 APPLICATION OF TRUST MONEY.

         Subject to the provisions of the last paragraph of Section 10.3, all
money deposited with the Trustee pursuant to Section 4.1 shall be held in trust
and applied by it, in accordance with the provisions of the Securities and this
Indenture, to the payment, either directly or through any Paying Agent
(including the Company acting as its own Paying Agent) as the Trustee may
determine, to the Persons entitled thereto, of the principal and any premium and
interest for whose payment such money has been deposited with the Trustee.


                                                                            -34-
<PAGE>
                                   ARTICLE 5

                                    REMEDIES

SECTION 5.1 EVENTS OF DEFAULT.

         "Event of Default," wherever used herein with respect to Securities of
any series, means any one of the following events (whatever the reason for such
Event of Default and whether it shall be voluntary or involuntary or be effected
by operation of law or pursuant to any judgment, decree or order of any court or
any order, rule or regulation of any administrative or governmental body),
unless in the Board Resolution, supplemental indenture or Officers' Certificate
establishing such series, it is provided that such series shall not have the
benefit of said Event of Default:

                  (1) default in the payment of any interest upon any Security
         of that series when it becomes due and payable, and continuance of such
         default for a period of 30 days; or

                  (2) default in the payment of the principal of or any premium
         on any Security of that series at its Maturity; or

                  (3) default in the deposit of any sinking fund payment, when
         and as due by the terms of a Security of that series; or

                  (4) default in the performance, or breach, of any covenant or
         warranty of the Company in this Indenture (other than a covenant or
         warranty a default in whose performance or whose breach is elsewhere in
         this Section specifically dealt with or which has expressly been
         included in this Indenture solely for the benefit of series of
         Securities other than that series), and continuance of such default or
         breach for a period of 90 days after there has been given, by
         registered or certified mail, to the Company by the Trustee or to the
         Company and the Trustee by the Holders of at least 25% in principal
         amount of the Outstanding Securities of that series a written notice
         specifying such default or breach and requiring it to be remedied and
         stating that such notice is a "Notice of Default" hereunder; or

                  (5) the entry by a court having jurisdiction in the premises
         of (A) a decree or order for relief in respect of the Company in an
         involuntary case or proceeding under any applicable Federal or State
         bankruptcy, insolvency, reorganization or other similar law or (B) a
         decree or order adjudging the Company a bankrupt or insolvent, or
         approving as properly filed a petition seeking reorganization,
         arrangement, adjustment or composition of or in respect of the Company
         under any applicable Federal or State law, or appointing a custodian,
         receiver, liquidator, assignee, trustee, sequestrator or other similar
         official of the Company or of any substantial part of its property, or
         ordering the winding up or liquidation of its affairs, and the
         continuance of any such decree or order for relief or any such other
         decree or order unstayed and in effect for a period of 90 consecutive
         days; or


                                                                            -35-
<PAGE>
                  (6) the commencement by the Company of a voluntary case or
         proceeding under any applicable Federal or State bankruptcy,
         insolvency, reorganization or other similar law or of any other case or
         proceeding to be adjudicated a bankrupt or insolvent, or the consent by
         it to the entry of a decree or order for relief in respect of the
         Company in an involuntary case or proceeding under any applicable
         Federal or State bankruptcy, insolvency, reorganization or other
         similar law or to the commencement of any bankruptcy or insolvency case
         or proceeding against it, or the filing by it of a petition or answer
         or consent seeking reorganization or relief under any applicable
         Federal or State law, or the consent by it to the filing of such
         petition or to the appointment of or taking possession by a custodian,
         receiver, liquidator, assignee, trustee, sequestrator or other similar
         official of the Company or of any substantial part of its property, or
         the making by it of an assignment for the benefit of creditors, or the
         admission by it in writing of its inability to pay its debts generally
         as they become due, or the taking of corporate action by the Company in
         furtherance of any such action; or

                  (7) any other Event of Default provided with respect to
         Securities of that series in the Board Resolution, supplemental
         indenture or Officers' Certificate establishing that series.

SECTION 5.2 ACCELERATION OF MATURITY; RESCISSION AND ANNULMENT.

         Unless the Board Resolution, supplemental indenture or Officers'
Certificate establishing such series provides otherwise, if an Event of Default
(other than an Event of Default specified in Section 5.1(5) or 5.1(6)) with
respect to Securities of any series at the time Outstanding occurs and is
continuing, then in every such case the Trustee or the Holders of not less than
25% in principal amount of the Outstanding Securities of that series may declare
the principal amount of all the Securities of that series (or, if any Securities
of that series are Original Issue Discount Securities, such portion of the
principal amount of such Securities as may be specified by the terms thereof),
and premium, if any, together with accrued and unpaid interest, if any, thereon,
to be due and payable immediately, by a notice in writing to the Company (and to
the Trustee if given by the Holders), and upon any such declaration such
principal amount (or specified amount), and premium, if any, together with
accrued and unpaid interest, if any, thereon, shall become immediately due and
payable. If an Event of Default specified in Section 5.1(5) or 5.1(6) with
respect to Securities of any series at the time Outstanding occurs, the
principal amount of all the Securities of that series (or, if any Securities of
that series are Original Issue Discount Securities, such portion of the
principal amount of such Securities as may be specified by the terms thereof),
and premium, if any, together with accrued and unpaid interest, if any, thereon,
shall automatically, and without any declaration or other action on the part of
the Trustee or any Holder, become immediately due and payable.

         At any time after such a declaration of acceleration with respect to
Securities of any series has been made and before a judgment or decree for
payment of the money due has been obtained by the Trustee as hereinafter in this
Article provided, the Holders of a majority in principal amount of the
Outstanding Securities of that series, by written notice to the Company and the
Trustee, may rescind and annul such declaration and its consequences if

                  (1) the Company has paid or deposited with the Trustee a sum
         sufficient to pay


                                                                            -36-
<PAGE>
                        (A) all overdue interest on all Securities of that
         series,

                        (B) the principal of (and premium, if any, on) any
         Securities of that series which have become due otherwise than by such
         declaration of acceleration and any interest thereon at the rate or
         rates prescribed therefor in such Securities,

                        (C) to the extent that payment of such interest is
         lawful, interest upon overdue interest at the rate or rates prescribed
         therefor in such Securities, and

                        (D) all sums paid or advanced by the Trustee hereunder
         and the reasonable compensation, expenses, disbursements and advances
         of the Trustee, its agents and counsel; and

                  (2) all Events of Default with respect to Securities of that
         series, other than the non-payment of the principal of Securities of
         that series that have become due solely by such declaration of
         acceleration, have been cured or waived as provided in Section 5.13.

         No such rescission shall affect any subsequent default or impair any
right consequent thereon.

SECTION 5.3 COLLECTION OF INDEBTEDNESS AND SUITS FOR ENFORCEMENT BY TRUSTEE.

         The Company covenants that if

                  (1) default is made in the payment of any interest on any
         Security when such interest becomes due and payable and such default
         continues for a period of 30 days, or

                  (2) default is made in the payment of the principal of (or
         premium, if any, on) any Security at the Maturity thereof, the Company
         will, upon demand of the Trustee, pay to it, for the benefit of the
         Holders of such Securities, the whole amount then due and payable on
         such Securities for principal and any premium and interest and, to the
         extent that payment of such interest shall be legally enforceable,
         interest on any overdue principal and premium and on any overdue
         interest, at the rate or rates prescribed therefor in such Securities,
         and, in addition thereto, such further amount as shall be sufficient to
         cover the costs and expenses of collection, including the reasonable
         compensation, expenses, disbursements and advances of the Trustee, its
         agents and counsel.

         If an Event of Default with respect to Securities of any series occurs
and is continuing, the Trustee may in its discretion proceed to protect and
enforce its rights and the rights of the Holders of Securities of such series by
such appropriate judicial proceedings as the Trustee shall deem most effectual
to protect and enforce any such rights, whether for the specific enforcement of
any covenant or agreement in this Indenture or in aid of the exercise of any
power granted herein, or to enforce any other proper remedy.


                                                                            -37-
<PAGE>
SECTION 5.4 TRUSTEE MAY FILE PROOFS OF CLAIM.

         In case of any judicial proceeding relative to the Company (or any
other obligor upon the Securities), its property or its creditors, the Trustee
shall be entitled and empowered, by intervention in such proceeding or
otherwise, to take any and all actions authorized under the Trust Indenture Act
in order to have claims of the Holders and the Trustee allowed in any such
proceeding. In particular, the Trustee shall be authorized to collect and
receive any moneys or other property payable or deliverable on any such claims
and to distribute the same; and any custodian, receiver, assignee, trustee,
liquidator, sequestrator or other similar official in any such judicial
proceeding is hereby authorized by each Holder to make such payments to the
Trustee and, in the event that the Trustee shall consent to the making of such
payments directly to the Holders, to pay to the Trustee any amount due it for
the reasonable compensation, expenses, disbursements and advances of the
Trustee, its agents and counsel, and any other amounts due the Trustee under
Section 6.7.

         No provision of this Indenture shall be deemed to authorize the Trustee
to authorize or consent to or accept or adopt on behalf of any Holder any plan
of reorganization, arrangement, adjustment or composition affecting the
Securities or the rights of any Holder thereof or to authorize the Trustee to
vote in respect of the claim of any Holder in any such proceeding; provided,
however, that the Trustee may, on behalf of the Holders, vote for the election
of a trustee in bankruptcy or similar official and be a member of a creditors'
or other similar committee.

SECTION 5.5 TRUSTEE MAY ENFORCE CLAIMS WITHOUT POSSESSION OF SECURITIES.

         All rights of action and claims under this Indenture or the Securities
may be prosecuted and enforced by the Trustee without the possession of any of
the Securities or the production thereof in any proceeding relating thereto, and
any such proceeding instituted by the Trustee shall be brought in its own name
as trustee of an express trust, and any recovery of judgment shall, after
provision for the payment of the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel, be for the
ratable benefit of the Holders of the Securities in respect of which such
judgment has been recovered.

SECTION 5.6 APPLICATION OF MONEY COLLECTED.

         Any money collected by the Trustee pursuant to this Article shall be
applied in the following order, at the date or dates fixed by the Trustee and,
in case of the distribution of such money on account of principal or any premium
or interest, upon presentation of the Securities and the notation thereon of 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 6.7;

         SECOND: To the payment of the amounts then due and unpaid for principal
of and any premium, if any, and interest on the Securities in respect of which
or for the benefit of which such money has been collected, ratably, without
preference or priority of any kind, according to the amounts due and payable on
such Securities for principal and any premium, if any, and interest,
respectively; and


                                                                            -38-
<PAGE>
         THIRD: The balance, if any, to the Company or any other Person or
Persons entitled thereto.

SECTION 5.7 LIMITATION ON SUITS.

         No Holder of any Security of any series shall have any right to
institute any proceeding, judicial or otherwise, with respect to this Indenture,
or for the appointment of a receiver or trustee, or for any other remedy
hereunder, unless

                  (1) such Holder has previously given written notice to the
         Trustee of a continuing Event of Default with respect to the Securities
         of that series;

                  (2) the Holders of not less than 25% in principal amount of
         the Outstanding Securities of that series shall have made written
         request to the Trustee to institute proceedings in respect of such
         Event of Default in its own name as Trustee hereunder;

                  (3) such Holder or Holders have offered to the Trustee
         reasonable indemnity against the costs, expenses and liabilities to be
         incurred in compliance with such request;

                  (4) the Trustee for 60 days after its receipt of such notice,
         request and offer of indemnity has failed to institute any such
         proceeding; and

                  (5) no direction inconsistent with such written request has
         been given to the Trustee during such 60-day period by the Holders of a
         majority in principal amount of the Outstanding Securities of that
         series;

it being understood and intended that no one or more of such Holders shall have
any right in any manner whatever by virtue of, or by availing of, any provision
of this Indenture to affect, disturb or prejudice the rights of any other of
such Holders, or to obtain or to seek to obtain priority or preference over any
other of such Holders or to enforce any right under this Indenture, except in
the manner herein provided and for the equal and ratable benefit of all of such
Holders.

SECTION 5.8 UNCONDITIONAL RIGHT OF HOLDERS TO RECEIVE PRINCIPAL, PREMIUM AND
INTEREST AND TO CONVERT.

         Notwithstanding any other provision in this Indenture, the Holder of
any Security shall have the right, which is absolute and unconditional, to
receive payment of the principal of and any premium and (subject to Section 3.7)
interest on such Security on the respective Stated Maturities expressed in such
Security (or, in the case of redemption, on the Redemption Date), to convert
such Securities in accordance with Article 14 to the extent that such right to
convert is applicable to such Security, and to institute suit for the
enforcement of any such payment, and such rights shall not be impaired without
the consent of such Holder.

                                                                            -39-
<PAGE>
SECTION 5.9 RESTORATION OF RIGHTS AND REMEDIES.

         If the Trustee or any Holder has instituted any proceeding to enforce
any right or remedy under this Indenture and such proceeding has been
discontinued or abandoned for any reason, or has been determined adversely to
the Trustee or to such Holder, then and in every such case, subject to any
determination in such proceeding, the Company, the Trustee and the Holders shall
be restored severally and respectively to their former positions hereunder and
thereafter all rights and remedies of the Trustee and the Holders shall continue
as though no such proceeding had been instituted.

SECTION 5.10 RIGHTS AND REMEDIES CUMULATIVE.

         Except as otherwise provided with respect to the replacement or payment
of mutilated, destroyed, lost or stolen Securities in the last paragraph of
Section 3.6, no right or remedy herein conferred upon or reserved to the Trustee
or to the Holders is intended to be exclusive of any other right or remedy, and
every right and remedy shall, to the extent permitted by law, be cumulative and
in addition to every other right and remedy given hereunder or now or hereafter
existing at law or in equity or otherwise. The assertion or employment of any
right or remedy hereunder, or otherwise, shall not prevent the concurrent
assertion or employment of any other appropriate right or remedy.

SECTION 5.11 DELAY OR OMISSION NOT WAIVER.

         No delay or omission of the Trustee or of any Holder of any Securities
to exercise any right or remedy accruing upon any Event of Default shall impair
any such right or remedy or constitute a waiver of any such Event of Default or
an acquiescence therein. Every right and remedy given by this Article or by law
to the Trustee or to the Holders may be exercised from time to time, and as
often as may be deemed expedient, by the Trustee (subject to the limitations
contained in this Indenture) or by the Holders, as the case may be.

SECTION 5.12 CONTROL BY HOLDERS.

         The Holders of a majority in principal amount of the Outstanding
Securities of any series 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, with respect to the
Securities of such series, provided that

                  (1) such direction shall not be in conflict with any rule of
         law or with this Indenture and the Trustee shall not have determined
         that the action so directed would be unjustly prejudicial to Holders of
         Securities of that series, or any other series, not taking part in such
         direction; and

                  (2) the Trustee may take any other action deemed proper by the
         Trustee that is not inconsistent with such direction or this Indenture.


                                                                            -40-
<PAGE>
SECTION 5.13 WAIVER OF PAST DEFAULTS.

         The Holders of not less than a majority in principal amount of the
Outstanding Securities of any series may on behalf of the Holders of all the
Securities of such series waive any past default hereunder with respect to such
series and its consequences, except

                  (1) a default in the payment of the principal of or any
         premium or interest on any Security of such series as and when the same
         shall become due and payable by the terms thereof, otherwise than by
         acceleration (unless such default has been cured and a sum sufficient
         to pay all matured installments of interest, principal and premium, if
         any, has been deposited with the Trustee), or

                  (2) to the extent such right is applicable to such Security, a
         failure by the Company on request to convert any Security into Common
         Stock; or

                  (3) in respect of a covenant or provision hereof which under
         Article 9 cannot be modified or amended without the consent of the
         Holder of each Outstanding Security of such series affected.

         Upon any such waiver, such default shall cease to exist, and any Event
of Default arising therefrom shall be deemed to have been cured, for every
purpose of this Indenture; but no such waiver shall extend to any subsequent or
other default or impair any right consequent thereon.

SECTION 5.14 UNDERTAKING FOR COSTS.

         In any suit for the enforcement of any right or remedy under this
Indenture, or in any suit against the Trustee for any action taken, suffered or
omitted by it as Trustee, a court may require any party litigant in such suit to
file an undertaking to pay the costs of such suit, and may assess costs against
any such party litigant, in the manner and to the extent provided in the Trust
Indenture Act; provided that neither this Section nor the Trust Indenture Act
shall be deemed to authorize any court to require such an undertaking or to make
such an assessment in any suit instituted by the Company or in any suit for the
enforcement of the right to convert any Security in accordance with Article 14.

SECTION 5.15 WAIVER OF USURY, STAY OR EXTENSION LAWS.

         The Company covenants (to the extent that it may lawfully do so) that
it will not at any time insist upon, or plead, or in any manner whatsoever claim
or take the benefit or advantage of, any usury, stay or extension law wherever
enacted, now or at any time hereafter in force, which may affect the covenants
or the performance of this Indenture; and the Company (to the extent that it may
lawfully do so) hereby expressly waives all benefit or advantage of any such law
and covenants that it will not 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.


                                                                            -41-
<PAGE>
                                   ARTICLE 6

                                   THE TRUSTEE

SECTION 6.1 CERTAIN DUTIES AND RESPONSIBILITIES.

         The duties and responsibilities of the Trustee shall be as provided by
the Trust Indenture Act. Notwithstanding the foregoing, no provision of this
Indenture shall require the Trustee to expend or risk its own funds or otherwise
incur any financial liability in the performance of any of its duties hereunder,
or in the exercise of any of its rights or powers if it shall have reasonable
grounds for believing that repayment of such funds or adequate indemnity against
such risk or liability is not reasonably assured to it. Whether or not therein
expressly so 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.

SECTION 6.2 NOTICE OF DEFAULTS.

         If a default occurs hereunder with respect to Securities of any series,
the Trustee shall give the Holders of Securities of such series notice of such
default as and to the extent provided by the Trust Indenture Act; provided,
however, that except in the case of a default in the payment of principal of (or
premium, if any) or interest on any Securities of such series or in the payment
of any sinking fund installment or any conversion right applicable to Securities
of such series, 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 determine that the withholding of such notice is in the
interests of the holders of Securities of such series; provided, further,
however, that in the case of any default of the character specified in Section
5.1(4) with respect to Securities of such series, no such notice to Holders
shall be given until at least 60 days after the occurrence thereof. For the
purpose of this Section, the term "default" means any event that is, or after
notice or lapse of time or both would become, an Event of Default with respect
to Securities of such series.

         Except with respect to Section 10.1, the Trustee shall have no duty to
inquire as to the performance of the Company with respect to the covenants
contained in Article 10. In addition, the Trustee shall not be deemed to have
knowledge of an Event of Default except (i) any Default or Event of Default
occurring pursuant to Sections 5.1(1), 5.1(2) and 5.1(3) (defaults in payments
on the Securities) or (ii) any Default or Event of Default of which the Trustee
shall have received written notification or obtained actual knowledge.

         Delivery of reports, information and documents to the Trustee under
Section 7.4 is for informational purposes only and the Trustee's receipt of the
foregoing shall not constitute constructive notice of any information contained
therein or determinable from information contained therein, including the
Company's compliance with any of their covenants hereunder (as to which the
Trustee is entitled to rely conclusively on Officers' Certificates).


                                                                            -42-
<PAGE>
SECTION 6.3 CERTAIN RIGHTS OF TRUSTEE.

         Subject to the provisions of Section 6.1:

                  (1) in the absence of bad faith on the part of the Trustee,
         the Trustee may rely and shall be protected in acting or refraining
         from acting upon any resolution, certificate, statement, instrument,
         opinion, report, notice, request, direction, consent, order, bond,
         debenture, note, other evidence of indebtedness or other paper or
         document believed by it to be genuine and to have been signed or
         presented by the proper party or parties;

                  (2) any request or direction of the Company mentioned herein
         shall be sufficiently evidenced by a Company Request or Company Order,
         and any resolution of the Board of Directors shall be sufficiently
         evidenced by a Board Resolution;

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

                  (4) the Trustee may consult with counsel and the written
         advice of such counsel or any Opinion of Counsel shall be full and
         complete authorization and protection in respect of any action taken,
         suffered or omitted by it hereunder in good faith and in reliance
         thereon;

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

                  (6) 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, note, other evidence of indebtedness
         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; and

                  (7) 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 with due care by it hereunder.


                                                                            -43-
<PAGE>
SECTION 6.4 NOT RESPONSIBLE FOR RECITALS OR ISSUANCE OF SECURITIES.

         The recitals contained herein and in the Securities, except the
Trustee's certificates of authentication, shall be taken as the statements of
the Company, and neither the Trustee nor any Authenticating Agent assumes any
responsibility for their correctness. The Trustee makes no representations as to
the validity, sufficiency or priority of this Indenture or of the Securities.
Neither the Trustee nor any Authenticating Agent shall be accountable for the
use or application by the Company of Securities or the proceeds thereof.

SECTION 6.5 MAY HOLD SECURITIES AND ACT AS TRUSTEE UNDER OTHER INDENTURES.

         The Trustee, any Authenticating Agent, any Paying Agent, any Security
Registrar or any other agent of the Company, in its individual or any other
capacity, may become the owner or pledgee of Securities and, subject to Sections
6.8 and 6.13, may otherwise deal with the Company with the same rights it would
have if it were not Trustee, Authenticating Agent, Paying Agent, Security
Registrar or such other agent.

         Subject to the limitations imposed by the Trust Indenture Act, nothing
in this Indenture shall prohibit the Trustee from becoming and acting as trustee
under other indentures under which other securities, or certificates of interest
of participation in other securities, of the Company are outstanding in the same
manner as if it were not Trustee hereunder.

SECTION 6.6 MONEY HELD IN TRUST.

         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
otherwise agreed with the Company.

SECTION 6.7 COMPENSATION AND REIMBURSEMENT.

         The Company agrees:

                  (1) to pay to the Trustee from time to time reasonable
         compensation for all services rendered by it hereunder (which
         compensation shall not be limited by any provision of law in regard to
         the compensation of a trustee of an express trust);

                  (2) except as otherwise expressly provided herein, to
         reimburse the Trustee upon its request for all reasonable expenses,
         disbursements and advances incurred or made by the Trustee in
         accordance with any provision of this Indenture (including the
         reasonable compensation and the expenses and disbursements of its
         agents and counsel), except any such expense, disbursement or advance
         as may be attributable to its negligence or bad faith; and

                  (3) to indemnify the Trustee for, and to hold it harmless
         against, any loss, liability or expense incurred without negligence or
         bad faith on its part, arising out of or in connection

                                                                            -44-
<PAGE>
         with the acceptance or administration of the trust or trusts hereunder,
         including the costs and expenses of defending itself against any claim
         or liability in connection with the exercise or performance of any of
         its powers or duties hereunder.

         When the Trustee incurs expenses or renders services after an Event of
Default specified in Section 5.1(5) or Section 5.1(6) hereof occurs, the
expenses and the compensation for the services (including the fees and expenses
of its agents and counsel) are intended to constitute expenses of administration
under any applicable bankruptcy, insolvency, reorganization or similar law.

SECTION 6.8 CONFLICTING INTERESTS.

         If the Trustee has or shall acquire a conflicting interest within the
meaning of the Trust Indenture Act and there is an Event of Default under the
Securities of that series, 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. To the extent
permitted by the Trust Indenture Act, the Trustee shall not be deemed to have a
conflicting interest by virtue of being a trustee under this Indenture with
respect to Securities of more than one series.

SECTION 6.9 CORPORATE TRUSTEE REQUIRED; ELIGIBILITY.

         There shall at all times be one (and only one) Trustee hereunder with
respect to the Securities of each series, which may be Trustee hereunder for
Securities of one or more other series. Each Trustee shall be a Person that is
eligible pursuant to the Trust Indenture Act to act as such and has (or if the
Trustee is a member of a bank holding company system, its bank holding company
has) a combined capital and surplus of at least $50,000,000. If any such Person
or bank holding company publishes reports of condition at least annually,
pursuant to law or to the requirements of its supervising or examining
authority, then for the purposes of this Section and to the extent permitted by
the Trust Indenture Act, the combined capital and surplus of such Person or bank
holding company 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 with respect to the Securities of any series shall cease to be eligible
in accordance with the provisions of this Section, it shall resign immediately
in the manner and with the effect hereinafter specified in this Article.

SECTION 6.10 RESIGNATION AND REMOVAL; APPOINTMENT OF SUCCESSOR.

         No resignation or removal of the Trustee and no appointment of a
successor Trustee pursuant to this Article shall become effective until the
acceptance of appointment by the successor Trustee in accordance with the
applicable requirements of Section 6.11.

         The Trustee may resign at any time with respect to the Securities of
one or more series by giving written notice thereof to the Company. If the
instrument of acceptance by a successor Trustee required by Section 6.11 shall
not have been delivered to the Trustee within 30 days after the giving of such
notice of resignation, the resigning Trustee may petition any court of competent
jurisdiction for the appointment of a successor Trustee with respect to the
Securities of such series.


                                                                            -45-
<PAGE>
         The Trustee may be removed at any time with respect to the Securities
of any series by Act of the Holders of a majority in principal amount of the
Outstanding Securities of such series, delivered to the Trustee and to the
Company.

         If at any time:

                  (1) the Trustee shall fail to comply with Section 6.8 after
         written request therefor by the Company or by any Holder who has been a
         bona fide Holder of a Security for at least six months, or

                  (2) the Trustee shall cease to be eligible under Section 6.9
         and shall fail to resign after written request therefor by the Company
         or by any such Holder, 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, (A) the Company by a Board Resolution may remove the
Trustee with respect to all Securities, or (B) subject to Section 5.14, any
Holder who has been a bona fide Holder of a Security for at least six months
may, on behalf of himself and all others similarly situated, petition any court
of competent jurisdiction for the removal of the Trustee with respect to all
Securities and the appointment of a successor Trustee or Trustees.

         If the Trustee shall resign, be removed or become incapable of acting,
or if a vacancy shall occur in the office of Trustee for any cause, with respect
to the Securities of one or more series, the Company, by a Board Resolution,
shall promptly appoint a successor Trustee or Trustees with respect to the
Securities of that or those series (it being understood that any such successor
Trustee may be appointed with respect to the Securities of one or more or all of
such series and that at any time there shall be only one Trustee with respect to
the Securities of any particular series) and shall comply with the applicable
requirements of Section 6.11. If, within one year after such resignation,
removal or incapability, or the occurrence of such vacancy, a successor Trustee
with respect to the Securities of any series shall be appointed by Act of the
Holders of a majority in principal amount of the Outstanding Securities of such
series delivered to the Company and the retiring Trustee, the successor Trustee
so appointed shall, forthwith upon its acceptance of such appointment in
accordance with the applicable requirements of Section 6.11, become the
successor Trustee with respect to the Securities of such series and to that
extent supersede the successor Trustee appointed by the Company. If no successor
Trustee with respect to the Securities of any series shall have been so
appointed by the Company or the Holders and accepted appointment in the manner
required by Section 6.11, the retiring Trustee may petition, or any Holder who
has been a bona fide Holder of a Security of such series for at least six months
may petition, on behalf of himself and all others similarly situated, any court
of competent jurisdiction for the appointment of a successor Trustee with
respect to the Securities of such series.


                                                                            -46-
<PAGE>
         The Company shall give notice of each resignation and each removal of
the Trustee with respect to the Securities of any series and each appointment of
a successor Trustee with respect to the Securities of any series to all Holders
of Securities of such series in the manner provided in Section 1.6. Each notice
shall include the name of the successor Trustee with respect to the Securities
of such series and the address of its Corporate Trust Office.

SECTION 6.11 ACCEPTANCE OF APPOINTMENT BY SUCCESSOR.

         In case of the appointment hereunder of a successor Trustee with
respect to all Securities, every such successor Trustee so appointed shall
execute, acknowledge and deliver to the Company and to the retiring Trustee an
instrument accepting such appointment, and thereupon the resignation or removal
of the retiring Trustee shall become effective and such successor Trustee,
without any further act, deed or conveyance, shall become vested with all the
rights, powers, trusts and duties of the retiring Trustee; but, on the request
of the Company or the successor Trustee, such retiring Trustee shall, upon
payment of its charges, execute and deliver an instrument transferring to such
successor Trustee all the rights, powers and trusts of the retiring Trustee and
shall duly assign, transfer and deliver to such successor Trustee all property
and money held by such retiring Trustee hereunder.

         In case of the appointment hereunder of a successor Trustee with
respect to the Securities of one or more (but not all) series, the Company, the
retiring Trustee and each successor Trustee with respect to the Securities of
one or more series shall execute and deliver an indenture supplemental hereto
wherein each successor Trustee shall accept such appointment and which (1) shall
contain such provisions as shall be necessary or desirable to transfer and
confirm to, and to vest in, each successor Trustee all the rights, powers,
trusts and duties of the retiring Trustee with respect to the Securities of that
or those series to which the appointment of such successor Trustee relates, (2)
if the retiring Trustee is not retiring with respect to all Securities, shall
contain such provisions as shall be deemed necessary or desirable to confirm
that all the rights, powers, trusts and duties of the retiring Trustee with
respect to the Securities of that or those series as to which the retiring
Trustee is not retiring shall continue to be vested in the retiring Trustee, and
(3) shall add to or change any of the provisions of this Indenture as shall be
necessary to provide for or facilitate the administration of the trusts
hereunder by more than one Trustee, it being understood that nothing herein or
in such supplemental indenture shall constitute such Trustees co-trustees of the
same trust and that each such Trustee shall be trustee of a trust or trusts
hereunder separate and apart from any trust or trusts hereunder administered by
any other such Trustee; and upon the execution and delivery of such supplemental
indenture the resignation or removal of the retiring Trustee shall become
effective to the extent provided therein and each such successor Trustee,
without any further act, deed or conveyance, shall become vested with all the
rights, powers, trusts and duties of the retiring Trustee with respect to the
Securities of that or those series to which the appointment of such successor
Trustee relates; but, on request of the Company or any successor Trustee, such
retiring Trustee shall duly assign, transfer and deliver to such successor
Trustee all property and money held by such retiring Trustee hereunder with
respect to the Securities of that or those series to which the appointment of
such successor Trustee relates.


                                                                            -47-
<PAGE>
         Upon request of any such successor Trustee, the Company shall execute
any and all instruments for more fully and certainly vesting in and confirming
to such successor Trustee all such rights, powers and trusts referred to in the
first or second preceding paragraph, as the case may be.

         No successor Trustee shall accept its appointment unless at the time of
such acceptance such successor Trustee shall be qualified and eligible under
this Article.

SECTION 6.12 MERGER, CONVERSION, CONSOLIDATION OR SUCCESSION TO BUSINESS.

         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 the corporate trust business
of the Trustee (including the administration of the trust created by this
Indenture), shall be the successor of the Trustee hereunder, provided such
corporation shall be otherwise qualified and eligible under this Article,
without the execution or filing of any paper or any further act on the part of
any of the parties hereto. In case any Securities shall have been authenticated,
but not delivered, by the Trustee then in office, any successor by merger,
conversion or consolidation to such authenticating Trustee may adopt such
authentication and deliver the Securities so authenticated with the same effect
as if such successor Trustee had itself authenticated such Securities. In the
event that any Securities shall not have been authenticated by such predecessor
Trustee, any such successor Trustee may authenticate and deliver such Securities
in either its own name or that of such predecessor Trustee, with the full force
and effect which this Indenture provides for the certificate of authentication
of the Trustee.

SECTION 6.13 PREFERENTIAL COLLECTION OF CLAIMS AGAINST COMPANY.

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

SECTION 6.14 APPOINTMENT OF AUTHENTICATING AGENT.

         The Trustee may appoint an Authenticating Agent or Agents with respect
to one or more series of Securities which shall be authorized to act on behalf
of the Trustee to authenticate Securities of such series issued upon original
issue and upon exchange, registration of transfer or partial redemption thereof
or pursuant to Section 3.6, and Securities so authenticated shall be entitled to
the benefits of this Indenture and shall be valid and obligatory for all
purposes as if authenticated by the Trustee hereunder. Wherever reference is
made in this Indenture to the authentication and delivery of Securities by the
Trustee or the Trustee's certificate of authentication, such reference shall be
deemed to include authentication and delivery on behalf of the Trustee by an
Authenticating Agent and a certificate of authentication executed on behalf of
the Trustee by an Authenticating Agent. Each Authenticating Agent shall be
acceptable to the Company and shall at all times be a corporation organized and
doing business under the laws of the United States of America, any State thereof
or the District of Columbia, authorized under such laws to act as Authenticating
Agent, having (or if the Authenticating Agent is a member of a bank holding
company system, its bank

                                                                            -48-
<PAGE>
holding company has) a combined capital and surplus of not less than $50,000,000
and subject to supervision or examination by Federal or State authority. If such
Authenticating Agent publishes reports of condition at least annually, pursuant
to law or to the requirements of said supervising or examining authority, then
for the purposes of this Section, the combined capital and surplus of such
Authenticating Agent 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 an
Authenticating Agent shall cease to be eligible in accordance with the
provisions of this Section, such Authenticating Agent shall resign immediately
in the manner and with the effect specified in this Section.

         Any corporation into which an Authenticating Agent may be merged or
converted or with which it may be consolidated, or any corporation resulting
from any merger, conversion or consolidation to which such Authenticating Agent
shall be a party, or any corporation succeeding to the corporate agency or
corporate trust business of an Authenticating Agent, shall continue to be an
Authenticating Agent, provided such corporation shall be otherwise eligible
under this Section, without the execution or filing of any paper or any further
act on the part of the Trustee or the Authenticating Agent.

         An Authenticating Agent may resign at any time by giving written notice
thereof to the Trustee and to the Company. The Trustee may at any time terminate
the agency of an Authenticating Agent by giving written notice thereof 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 such
Authenticating Agent shall cease to be eligible in accordance with the
provisions of this Section, the Trustee may appoint a successor Authenticating
Agent which shall be acceptable to the Company and shall give notice of such
appointment in the manner provided in Section 1.6 to all Holders of Securities
of the series with respect to which such Authenticating Agent will serve. Any
successor Authenticating Agent upon acceptance of its appointment hereunder
shall become vested with all the rights, powers and duties of its predecessor
hereunder, with like effect as if originally named as an Authenticating Agent.
No successor Authenticating Agent shall be appointed unless eligible under the
provisions of this Section.

         The Trustee agrees to pay to each Authenticating Agent from time to
time reasonable compensation for its services under this Section, and the
Trustee shall be entitled to be reimbursed for such payments, subject to the
provisions of Section 6.7.

         If an appointment with respect to one or more series is made pursuant
to this Section 6.12, the Securities of such series may have endorsed thereon,
in lieu of the Trustee's certificate of authentication, an alternative
certificate of authentication in the following form:

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

                                             ----------------------------,
                                             as Trustee


                                                                            -49-
<PAGE>
                                             By:
                                                 -------------------------------
                                                 as Authenticating Agent

                                             By:
                                                 -------------------------------
                                                 Authorized Officer

                                   ARTICLE 7

                HOLDERS' LISTS AND REPORTS BY TRUSTEE AND COMPANY

SECTION 7.1 COMPANY TO FURNISH TRUSTEE NAMES AND ADDRESSES OF HOLDERS.

         The Company will furnish or cause to be furnished to the Trustee

                  (1) semi-annually, not later than 15 days after the Regular
         Record Date for each respective series of Securities, a list, in such
         form as the Trustee may reasonably require, of the names and addresses
         of the Holders of Securities of each series as of such Regular Record
         Date, as the case may be, or if there is no Regular Record Date for
         such series of Securities, semi-annually, and

                  (2) at such other times as the Trustee may request in writing,
         within 30 days after the receipt by the Company of any such request, a
         list of similar form and content as of a date not more than 15 days
         prior to the time such list is furnished;

provided that no such list need be furnished by the Company to the Trustee so
long as the Trustee is acting as Security Registrar.

SECTION 7.2 PRESERVATION OF INFORMATION; COMMUNICATIONS TO HOLDERS.

         The Trustee shall preserve, in as current a form as is reasonably
practicable, the names and addresses of Holders contained in the most recent
list furnished to the Trustee as provided in Section 7.1 and the names and
addresses of Holders received by the Trustee in its capacity as Security
Registrar. The Trustee may destroy any list furnished to it as provided in
Section 7.1 upon receipt of a new list so furnished.

         The rights of Holders to communicate with other Holders with respect to
their rights under this Indenture or under the Securities, and the corresponding
rights and privileges of the Trustee, shall be as provided by the Trust
Indenture Act.

         Every Holder of Securities, 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 made pursuant to
the Trust Indenture Act.


                                                                            -50-
<PAGE>
SECTION 7.3 REPORTS BY TRUSTEE.

         The Trustee shall transmit to Holders such reports 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.

         Reports so required to be transmitted at stated intervals of not more
than 12 months shall be transmitted no later than July 15 in each calendar year,
commencing with the first July 15 after the first issuance of Securities
pursuant to this Indenture.

         A copy of each such report shall, at the time of such transmission to
Holders, be filed by the Trustee with each stock exchange upon which any
Securities are listed, with the Commission and with the Company. The Company
will notify the Trustee when any Securities are listed on any stock exchange.

SECTION 7.4 REPORTS BY COMPANY.

         The Company shall file with the Trustee and the Commission, and
transmit to Holders, 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 the Trust Indenture Act; provided
that any such information, documents or reports required to be filed with the
Commission pursuant to Section 13 or 15(d) of the Exchange Act shall be filed
with the Trustee within 15 days after the same is so required to be filed with
the Commission.

                                   ARTICLE 8

              CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE

SECTION 8.1 COMPANY MAY CONSOLIDATE, ETC., ONLY ON CERTAIN TERMS.

         The Company shall not consolidate with or merge into any other Person
(in a transaction in which the Company is not the surviving corporation) or
convey, transfer or lease its properties and assets substantially as an entirety
to any Person, unless:

                  (1) in case the Company shall consolidate with or merge into
         another Person (in a transaction in which the Company is not the
         surviving corporation) or convey, transfer or lease its properties and
         assets substantially as an entirety to any Person, the Person formed by
         such consolidation or into which the Company is merged or the Person
         which acquires by conveyance or transfer, or which leases, the
         properties and assets of the Company substantially as an entirety shall
         be a corporation, limited liability company, partnership or trust,
         shall be organized and validly existing under the laws of the United
         States of America, any State thereof or the District of Columbia and
         shall expressly assume, by an indenture supplemental hereto, executed
         and delivered to the Trustee, in form satisfactory to the Trustee, the
         due and punctual payment of the principal of and any premium and
         interest on

                                                                            -51-
<PAGE>
         all the Securities and the performance or observance of every covenant
         of this Indenture on the part of the Company to be performed or
         observed and the conversion rights shall be provided for in accordance
         with Article 14, if applicable, or as otherwise specified pursuant to
         Section 3.1, 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 which shall have
         acquired the Company's assets;

                  (2) immediately after giving effect to such transaction and
         treating any indebtedness which becomes an obligation of the Company or
         any Subsidiary as a result of such transaction as having been incurred
         by the Company or such Subsidiary at the time of such transaction, no
         Event of Default, and no event which, after notice or lapse of time or
         both, would become an Event of Default, shall have happened and be
         continuing; and

                  (3) the Company has delivered to the Trustee an Officers'
         Certificate and an Opinion of Counsel, each stating that such
         consolidation, merger, conveyance, transfer or lease and, if a
         supplemental indenture is required in connection with such transaction,
         such supplemental indenture comply with this Article and that all
         conditions precedent herein provided for relating to such transaction
         have been complied with.

SECTION 8.2 SUCCESSOR SUBSTITUTED.

         Upon any consolidation of the Company with, or merger of the Company
into, any other Person or any conveyance, transfer or lease of the properties
and assets of the Company substantially as an entirety in accordance with
Section 8.1, the successor Person formed by such consolidation or into which the
Company is merged or to which such conveyance, transfer or lease is made shall
succeed to, and be substituted for, and may exercise every right and power of,
the Company under this Indenture with the same effect as if such successor
Person had been named as the Company herein, and thereafter, except in the case
of a lease, the predecessor Person shall be relieved of all obligations and
covenants under this Indenture and the Securities.


                                                                            -52-
<PAGE>

                                   ARTICLE 9

                             SUPPLEMENTAL INDENTURES

SECTION  9.1 SUPPLEMENTAL INDENTURES WITHOUT CONSENT OF HOLDERS.

         Without the consent of any Holders, the Company, when authorized by a
Board Resolution, and the Trustee, at any time and from time to time, may enter
into one or more indentures supplemental hereto, in form satisfactory to the
Trustee, for any of the following purposes:

                  (1)      to evidence the succession of another Person to the
         Company, or successive successions, and the assumption by any such
         successor of the covenants of the Company herein and in the Securities
         in compliance with Article 8; or

                  (2)      to add to the covenants of the Company for the
         benefit of the Holders of all or any series of Securities (and if such
         covenants are to be for the benefit of less than all series of
         Securities, stating that such covenants are expressly being included
         solely for the benefit of such series) or to surrender any right or
         power herein conferred upon the Company; or

                  (3)      to add any additional Events of Default for the
         benefit of the Holders of all or any series of Securities (and if such
         additional Events of Default are to be for the benefit of less than all
         series of Securities, stating that such additional Events of Default
         are expressly being included solely for the benefit of such series); or

                  (4)      to add to or change any of the provisions of this
         Indenture to such extent as shall be necessary to permit or facilitate
         the issuance of Securities in bearer form, registrable or not
         registrable as to principal, and with or without interest coupons, or
         to permit or facilitate the issuance of Securities in uncertificated
         form; or

                  (5)      to add to, change or eliminate any of the provisions
         of this Indenture in respect of one or more series of Securities,
         provided that any such addition, change or elimination (A) shall
         neither (i) apply to any Security of any series created prior to the
         execution of such supplemental indenture and entitled to the benefit of
         such provision nor (ii) modify the rights of the Holder of any such
         Security with respect to such provision or (B) shall become effective
         only when there is no such Security Outstanding; or

                  (6)      to secure the Securities, including provisions
         regarding the circumstances under which collateral may be released or
         substituted; or

                  (7)      to add or provide for a guaranty of the Securities or
         additional obligors on the Securities; or


                                                                            -53-
<PAGE>

                  (8)      to establish the form or terms of Securities of any
         series as permitted by Sections 2.1 and 3.1; or

                  (9)      to evidence and provide for the acceptance of
         appointment hereunder by a successor Trustee with respect to the
         Securities of one or more series and to add to or change any of the
         provisions of this Indenture as shall be necessary to provide for or
         facilitate the administration of the trusts hereunder by more than one
         Trustee, pursuant to the requirements of Section 6.11; or

                  (10)     to cure any ambiguity, to correct or supplement any
         provision herein which may be defective or inconsistent with any other
         provision herein, or to make any other provisions with respect to
         matters or questions arising under this Indenture, provided that such
         action pursuant to this clause (10) shall not adversely affect the
         interests of the Holders of Securities of any series in any material
         respect; or

                  (11)     to supplement any of the provisions of the Indenture
         to such extent as shall be necessary to permit or facilitate the
         defeasance and discharge of any series of Securities pursuant to
         Articles 4 and 13, provided that any such action shall not adversely
         affect the interests of the Holders of Securities of such series or any
         other series of Securities in any material respect.

SECTION  9.2 SUPPLEMENTAL INDENTURES WITH CONSENT OF HOLDERS.

         With the consent of the Holders of a majority in principal amount of
the Outstanding Securities of each series affected by such supplemental
indenture, by Act of said Holders delivered to the Company and the Trustee, the
Company, when authorized by a Board Resolution, and the Trustee may 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 of modifying in any manner the rights of the Holders of
Securities of such series under this Indenture; provided, however, that no such
supplemental indenture shall, without the consent of the Holder of each
Outstanding Security affected thereby,

                  (1)      change the Stated Maturity of the principal of, or
         any installment of principal of or interest on, any Security, or reduce
         the principal amount thereof or the rate of interest thereon or any
         premium payable upon the redemption thereof, or reduce the amount of
         the principal of an Original Issue Discount Security or any other
         Security which would be due and payable upon a declaration of
         acceleration of the Maturity thereof pursuant to Section 5.2, or change
         the coin or currency in which, any Security or any premium or interest
         thereon is payable, or impair the right to institute suit for the
         enforcement of any such payment on or after the Stated Maturity thereof
         (or, in the case of redemption, on or after the Redemption Date), or
         modify the provisions of this Indenture in the case of Securities of
         any series that are convertible into Securities or other securities of
         the Company, adversely affect the right of Holders to convert any of
         the Securities of such series other than as provided in or pursuant to
         this Indenture, or


                                                                            -54-
<PAGE>

                  (2)      reduce the percentage in principal amount of the
         Outstanding Securities of any series, the consent of whose Holders is
         required for any such supplemental indenture, or the consent of whose
         Holders is required for any waiver (of compliance with certain
         provisions of this Indenture or certain defaults hereunder and their
         consequences) provided for in this Indenture, or

                  (3)      modify any of the provisions of this Section, Section
         5.13 or Section 10.8, except to increase any such percentage or to
         provide that certain other provisions of this Indenture cannot be
         modified or waived without the consent of the Holder of each
         Outstanding Security affected thereby; provided, however, that this
         clause shall not be deemed to require the consent of any Holder with
         respect to changes in the references to "the Trustee" and concomitant
         changes in this Section and Section 10.8, or the deletion of this
         proviso, in accordance with the requirements of Sections 6.11 and
         9.1(8), or

                  (4)      if applicable, make any change that adversely affects
         the right to convert any security as provided in Article 14 or pursuant
         to Section 3.1 (except as permitted by Section 9.1(9)) or decrease the
         conversion rate or increase the conversion price of any such security.

         A supplemental indenture which changes or eliminates any covenant or
other provision of this Indenture which has expressly been included solely for
the benefit of one or more particular series of Securities, or which modifies
the rights of the Holders of Securities of such series with respect to such
covenant or other provision, shall be deemed not to affect the rights under this
Indenture of the Holders of Securities of any other series.

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

SECTION  9.3 EXECUTION OF SUPPLEMENTAL INDENTURES.

         In executing, or accepting the additional trusts created by, any
supplemental indenture permitted by this Article or the modifications thereby of
the trusts created by this Indenture, the Trustee shall be entitled to receive,
and (subject to Sections 6.1 and 6.3) shall be fully protected in relying upon,
an Opinion of Counsel stating that the execution of such supplemental indenture
is authorized or permitted by this Indenture. The Trustee may, but shall not be
obligated to, enter into any such supplemental indenture which affects the
Trustee's own rights, duties or immunities under this Indenture or otherwise.

SECTION  9.4 EFFECT OF SUPPLEMENTAL INDENTURES.

         Upon the execution of any supplemental indenture under this Article,
this Indenture shall be modified in accordance therewith, and such supplemental
indenture shall form a part of this Indenture for all purposes; and every Holder
of Securities theretofore or thereafter authenticated and delivered hereunder
shall be bound thereby.


                                                                            -55-
<PAGE>

SECTION 9.5 CONFORMITY WITH TRUST INDENTURE ACT.

         Every supplemental indenture executed pursuant to this Article shall
conform to the requirements of the Trust Indenture Act.

SECTION  9.6 REFERENCE IN SECURITIES TO SUPPLEMENTAL INDENTURES.

         Securities of any series authenticated and delivered after the
execution of any supplemental indenture pursuant to this Article may, and shall
if required by the Trustee, bear a notation in form approved by the Trustee as
to any matter provided for in such supplemental indenture. If the Company shall
so determine, new Securities of any series so modified as to conform, in the
opinion of the Trustee and the Company, to any such supplemental indenture may
be prepared and executed by the Company and authenticated and delivered by the
Trustee in exchange for Outstanding Securities of such series.

                                   ARTICLE 10

                                    COVENANTS

SECTION  10.1 PAYMENT OF PRINCIPAL, PREMIUM AND INTEREST.

         The Company covenants and agrees for the benefit of each series of
Securities that it will duly and punctually pay the principal of and any premium
and interest on the Securities of that series in accordance with the terms of
the Securities and this Indenture.

SECTION  10.2 MAINTENANCE OF OFFICE OR AGENCY.

         The Company will maintain in each Place of Payment for any series of
Securities an office or agency where Securities of that series may be presented
or surrendered for payment, where Securities of that series may be surrendered
for registration of transfer or exchange, where Securities of that series may be
surrendered for conversion and where notices and demands to or upon the Company
in respect of the Securities of that series and this Indenture may be served.
The Company will give prompt written notice to the Trustee of the location, and
any change in the location, of such office or agency. If at any time the Company
shall fail to maintain any such required office or agency or shall fail to
furnish the Trustee with the address thereof, such presentations, surrenders,
notices and demands may be made or served at the Corporate Trust Office of the
Trustee, and the Company hereby appoints the Trustee as its agent to receive all
such presentations, surrenders, notices and demands. Unless otherwise provided
in a supplemental indenture or pursuant to Section 3.1 hereof, the Place of
Payment for any series of Securities shall be the Corporate Trust Office of the
Trustee.

         The Company may also from time to time designate one or more other
offices or agencies where the Securities of one or more series may be presented
or surrendered for any or all such purposes and may from time to time rescind
such designations; provided, however, that no such


                                                                            -56-
<PAGE>

designation or rescission shall in any manner relieve the Company of its
obligation to maintain an office or agency in each Place of Payment for
Securities of any series for such purposes. The Company will give prompt written
notice to the Trustee of any such designation or rescission and of any change in
the location of any such other office or agency.

SECTION  10.3 MONEY FOR SECURITIES PAYMENTS TO BE HELD IN TRUST.

         If the Company shall at any time act as its own Paying Agent with
respect to any series of Securities, it will, on or before each due date of the
principal of or any premium or interest on any of the Securities of that series,
segregate and hold in trust for the benefit of the Persons entitled thereto a
sum sufficient to pay the principal and any premium and interest so becoming due
until such sums shall be paid to such Persons or otherwise disposed of as herein
provided and will promptly notify the Trustee of its action or failure so to
act.

         Whenever the Company shall have one or more Paying Agents for any
series of Securities, it will, on or prior to each due date of the principal of
or any premium or interest on any Securities of that series, deposit with a
Paying Agent a sum sufficient to pay such amount, such sum to be held as
provided by the Trust Indenture Act, and (unless such Paying Agent is the
Trustee) the Company will promptly notify the Trustee of its action or failure
so to act.

         The Company will cause each Paying Agent for any series of Securities
other than the Trustee to execute and deliver to the Trustee an instrument in
which such Paying Agent shall agree with the Trustee, subject to the provisions
of this Section, that such Paying Agent will (1) comply with the provisions of
the Trust Indenture Act applicable to it as a Paying Agent and (2) during the
continuance of any default by the Company (or any other obligor upon the
Securities of that series) in the making of any payment in respect of the
Securities of that series, upon the written request of the Trustee, forthwith
pay to the Trustee all sums held in trust by such Paying Agent for payment in
respect of the Securities of that series.

         The Company may at any time, for the purpose of obtaining the
satisfaction and discharge of this Indenture or for any other purpose, pay, or
by Company Order direct any Paying Agent to pay, to the Trustee all sums held in
trust by the Company or such Paying Agent, such sums to be held by the Trustee
upon the same trusts as those upon which such sums were held by the Company or
such Paying Agent; and, upon such payment by any Paying Agent to the Trustee,
such Paying Agent shall be released from all further liability with respect to
such money.

         Any money deposited with the Trustee or any Paying Agent, or then held
by the Company, in trust for the payment of the principal of or any premium or
interest on any Security of any series and remaining unclaimed for a period
ending on the earlier of the date that is ten Business Days prior to the date
such money would escheat to the State or two years after such principal, premium
or interest has become due and payable shall be paid to the Company on Company
Request, or (if then held by the Company) shall be discharged from such trust;
and the Holder of such Security shall thereafter, as an unsecured general
creditor, look only to the Company for payment thereof, and all liability of the
Trustee or such Paying Agent with respect to such trust money, and all liability
of the Company as trustee thereof, shall thereupon cease; provided, however,
that the Trustee or such Paying Agent,


                                                                            -57-
<PAGE>

before being required to make any such repayment, may at the expense of the
Company cause to be published once, in a newspaper published in the English
language, customarily published on each Business Day and of general circulation
in each Place of Payment, notice that such money remains unclaimed and that,
after a date specified therein, which shall not be less than 30 days from the
date of such publication, any unclaimed balance of such money then remaining
will be repaid to the Company.

SECTION  10.4 STATEMENT BY OFFICERS AS TO DEFAULT.

         The Company will deliver to the Trustee, within 120 days after the end
of each fiscal year of the Company ending after the date hereof, an Officers'
Certificate, stating whether or not to the best knowledge of the signers 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 status thereof of
which they may have knowledge. The fiscal year of the Company currently ends on
December 31; and the Company will give the Trustee prompt written notice of any
change of its fiscal year.

SECTION  10.5 EXISTENCE.

         Subject to Article 8, the Company will do or cause to be done all
things necessary to preserve and keep in full force and effect its existence.

SECTION  10.6 MAINTENANCE OF PROPERTIES.

         The Company will cause all properties used or useful in the conduct of
its business 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, and to the extent, 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 and not disadvantageous
in any material respect to the Holders.

SECTION  10.7 PAYMENT OF TAXES AND OTHER CLAIMS.

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

                                                                            -58-
<PAGE>

discharge would not have a material adverse effect on the assets, business,
operations, properties or condition (financial or otherwise) of the Company and
its subsidiaries, taken as a whole.

SECTION  10.8 WAIVER OF CERTAIN COVENANTS.

         Except as otherwise specified as contemplated by Section 3.1 for
Securities of such series, the Company may, with respect to the Securities of
any series, omit in any particular instance to comply with any term, provision
or condition set forth in any covenant provided pursuant to Section 3.1(19),
9.1(2), 9.1(7), 10.6 or 10.7 for the benefit of the Holders of such series if
before the time for such compliance the Holders of at least a majority in
principal amount of the Outstanding Securities of such series shall, by Act of
such Holders, either waive such compliance in such instance or generally waive
compliance with such term, provision or condition, but no such waiver shall
extend to or affect such term, provision or condition except to the extent so
expressly waived, and, until such waiver shall become effective, the obligations
of the Company and the duties of the Trustee in respect of any such term,
provision or condition shall remain in full force and effect.

                                   ARTICLE 11

                            REDEMPTION OF SECURITIES

SECTION  11.1 APPLICABILITY OF ARTICLE.

         Securities of any series that are redeemable before their Stated
Maturity shall be redeemable in accordance with their terms and (except as
otherwise specified as contemplated by Section 3.1 for such Securities) in
accordance with this Article.

SECTION  11.2 ELECTION TO REDEEM; NOTICE TO TRUSTEE.

         The election of the Company to redeem any Securities shall be evidenced
by a Board Resolution or in another manner specified as contemplated by Section
3.1 for such Securities. In case of any redemption at the election of the
Company of less than all the Securities of any series (including any such
redemption affecting only a single Security), the Company shall, at least 45
days prior to the Redemption Date fixed by the Company (unless a shorter notice
shall be satisfactory to the Trustee), notify the Trustee of such Redemption
Date, of the principal amount of Securities of such series to be redeemed and,
if applicable, of the tenor of the Securities to be redeemed. In the case of any
redemption of Securities prior to the expiration of any restriction on such
redemption provided in the terms of such Securities or elsewhere in this
Indenture, the Company shall furnish the Trustee with an Officers' Certificate
evidencing compliance with such restriction.

SECTION  11.3 SELECTION BY TRUSTEE OF SECURITIES TO BE REDEEMED.

         If less than all the Securities of any series are to be redeemed
(unless all the Securities of such series and of a specified tenor are to be
redeemed or unless such redemption affects only a single Security), the
particular Securities to be redeemed shall be selected not more than 45 days


                                                                            -59-
<PAGE>

prior to the Redemption Date by the Trustee, from the Outstanding Securities of
such series not previously called for redemption, by lot, or in the Trustee's
discretion, on a pro-rata basis, provided that the unredeemed portion of the
principal amount of any Security shall be in an authorized denomination (which
shall not be less than the minimum authorized denomination) for such Security.
If less than all the Securities of such series and of a specified tenor are to
be redeemed (unless such redemption affects only a single Security), the
particular Securities to be redeemed shall be selected not more than 45 days
prior to the Redemption Date by the Trustee, from the Outstanding Securities of
such series and specified tenor not previously called for redemption in
accordance with the preceding sentence.

         If any Security selected for partial redemption is converted in part
before termination of the conversion right with respect to the portion of the
Security so selected, the converted portion of such Security shall be deemed (so
far as may be) to be the portion selected for redemption. Securities that have
been converted during a selection of Securities to be redeemed shall be treated
by the Trustee as Outstanding for the purpose of such selection.

         The Trustee shall promptly notify the Company in writing of the
Securities selected for redemption as aforesaid and, in case of any Securities
selected for partial redemption as aforesaid, the principal amount thereof to be
redeemed.

         The provisions of the two preceding paragraphs shall not apply with
respect to any redemption affecting only a single Security, whether such
Security is to be redeemed in whole or in part. In the case of any such
redemption in part, the unredeemed portion of the principal amount of the
Security shall be in an authorized denomination (which shall not be less than
the minimum authorized denomination) for such Security.

         For all purposes of this Indenture, unless the context otherwise
requires, all provisions relating to the redemption of Securities shall relate,
in the case of any Securities redeemed or to be redeemed only in part, to the
portion of the principal amount of such Securities which has been or is to be
redeemed.

SECTION  11.4 NOTICE OF REDEMPTION.

         Notice of redemption shall be given by first-class mail, postage
prepaid, mailed not fewer than 30 nor more than 60 days prior to the Redemption
Date, unless a shorter period is specified in the Securities to be redeemed, to
each Holder of Securities to be redeemed, at its address appearing in the
Security Register.

         All notices of redemption shall state:

                  (1)      the Redemption Date,

                  (2)      the Redemption Price (including accrued interest, if
         any),


                                                                            -60-
<PAGE>

                  (3)      if less than all the Outstanding Securities of any
         series consisting of more than a single Security are to be redeemed,
         the identification (and, in the case of partial redemption of any such
         Securities, the principal amounts) of the particular Securities to be
         redeemed and, if less than all the Outstanding Securities of any series
         consisting of a single Security are to be redeemed, the principal
         amount of the particular Security to be redeemed,

                  (4)      in case any Security is to be redeemed in part only,
         that on and after the Redemption Date, upon surrender of such Security,
         the Holder of such Security will receive, without charge, a new
         Security or Securities of authorized denominations for the principal
         amount thereof remaining unredeemed,

                  (5)      that on the Redemption Date the Redemption Price will
         become due and payable upon each such Security to be redeemed and, if
         applicable, that interest thereon will cease to accrue on and after
         said date,

                  (6)      the place or places where each such Security is to be
         surrendered for payment of the Redemption Price,

                  (7)      if applicable, the conversion price, the date on
         which the right to convert the principal of the Securities or the
         portions thereof to be redeemed will terminate, and the place or places
         where such Securities may be surrendered for conversion,

                  (8)      that the redemption is for a sinking fund, if such is
         the case, and

                  (9)      the CUSIP number or numbers and/or common codes of
         the Security being redeemed.

         Notice of redemption of Securities to be redeemed at the election of
the Company shall be given by the Company or, at the Company's request, by the
Trustee in the name and at the expense of the Company and shall be irrevocable.

SECTION  11.5 DEPOSIT OF REDEMPTION PRICE.

         On or prior to any Redemption Date, the Company shall deposit with the
Trustee or with a Paying Agent (or, if the Company is acting as its own Paying
Agent, segregate and hold in trust as provided in Section 10.3) an amount of
money sufficient to pay the Redemption Price of, and (except if the Redemption
Date shall be an Interest Payment Date) accrued interest on, all the Securities
which are to be redeemed on that date.

         If any Security called for redemption is converted, any money deposited
with the Trustee or with a Paying Agent or so segregated and held in trust for
the redemption of such Security shall (subject to the right of any Holder of
such Security to receive interest as provided in the last paragraph of Section
3.7) be paid to the Company on Company Request, or if then held by the Company,
shall be discharged from such trust.


                                                                            -61-
<PAGE>

SECTION  11.6 SECURITIES PAYABLE ON REDEMPTION DATE.

         Notice of redemption having been given as aforesaid, the Securities so
to be redeemed shall, on the Redemption Date, become due and payable at the
Redemption Price therein specified, and from and after such date (unless the
Company shall default in the payment of the Redemption Price and accrued
interest) such Securities shall cease to bear interest. Upon surrender of any
such Security for redemption in accordance with said notice, such Security shall
be paid by the Company at the Redemption Price, together with accrued interest
to the Redemption Date; provided, however, that, unless otherwise specified as
contemplated by Section 3.1, installments of interest whose Stated Maturity is
on or prior to the Redemption Date will be payable to the Holders of such
Securities, or one or more Predecessor Securities, registered as such at the
close of business on the relevant Record Dates according to their terms and the
provisions of Section 3.7.

         If any Security called for redemption shall not be so paid upon
surrender thereof for redemption, the principal and any premium shall, until
paid, bear interest from the Redemption Date at the rate prescribed therefor in
the Security.

SECTION  11.7 SECURITIES REDEEMED IN PART.

         Any Security which is to be redeemed only in part shall be surrendered
at a Place of Payment therefor (with, if the Company or the Trustee so requires,
due endorsement by, or a written instrument of transfer in form satisfactory to
the Company and the Trustee duly executed by, the Holder thereof or its attorney
duly authorized in writing), and the Company shall execute, and the Trustee
shall authenticate and deliver to the Holder of such Security without service
charge, a new Security or Securities of the same series and of like tenor, of
any authorized denomination as requested by such Holder, in aggregate principal
amount equal to and in exchange for the unredeemed portion of the principal of
the Security so surrendered.

                                   ARTICLE 12

                                  SINKING FUNDS

SECTION  12.1 APPLICABILITY OF ARTICLE.

         The provisions of this Article shall be applicable to any sinking fund
for the retirement of Securities of any series except as otherwise specified as
contemplated by Section 3.1 for such Securities.

         The minimum amount of any sinking fund payment provided for by the
terms of any Securities is herein referred to as a "mandatory sinking fund
payment," and any payment in excess of such minimum amount provided for by the
terms of such Securities is herein referred to as an "optional sinking fund
payment." If provided for by the terms of any Securities, the cash amount of any
sinking fund payment may be subject to reduction as provided in Section 12.2.
Each sinking


                                                                            -62-
<PAGE>

fund payment shall be applied to the redemption of Securities as provided for by
the terms of such Securities.

SECTION  12.2 SATISFACTION OF SINKING FUND PAYMENTS WITH SECURITIES.

         The Company (1) may deliver Outstanding Securities of a series (other
than any previously called for redemption) and (2) may apply as a credit
Securities of a series which have been redeemed either at the election of the
Company pursuant to the terms of such Securities or through the application of
permitted optional sinking fund payments pursuant to the terms of such
Securities, in each case in satisfaction of all or any part of any sinking fund
payment with respect to any Securities of such series required to be made
pursuant to the terms of such Securities as and to the extent provided for by
the terms of such Securities; provided that the Securities to be so credited
have not been previously so credited. The Securities to be so credited shall be
received and credited for such purpose by the Trustee at the Redemption Price,
as specified in the Securities so to be redeemed, for redemption through
operation of the sinking fund and the amount of such sinking fund payment shall
be reduced accordingly.

SECTION  12.3 REDEMPTION OF SECURITIES FOR SINKING FUND.

         Not fewer than 60 days prior to each sinking fund payment date for any
Securities, the Company will deliver to the Trustee an Officers' Certificate
specifying the amount of the next ensuing sinking fund payment for such
Securities pursuant to the terms of such Securities, the portion thereof, if
any, which is to be satisfied by payment of cash and the portion thereof, if
any, which is to be satisfied by delivering and crediting Securities pursuant to
Section 12.2 and will also deliver to the Trustee any Securities to be so
delivered. Not fewer than 30 days prior to each such sinking fund payment date,
the Trustee shall select the Securities to be redeemed upon such sinking fund
payment date in the manner specified in Section 11.3 and cause notice of the
redemption thereof to be given in the name of and at the expense of the Company
in the manner provided in Section 11.4. Such notice having been duly given, the
redemption of such Securities shall be made upon the terms and in the manner
stated in Sections 11.6 and 11.7.

                                   ARTICLE 13

                       DEFEASANCE AND COVENANT DEFEASANCE

SECTION  13.1 COMPANY'S OPTION TO EFFECT DEFEASANCE OR COVENANT DEFEASANCE.

         The Company may elect, at its option at any time, to have Section 13.2
or Section 13.3 applied to any Securities or any series of Securities, as the
case may be, designated pursuant to Section 3.1 as being defeasible pursuant to
such Section 13.2 or 13.3, in accordance with any applicable requirements
provided pursuant to Section 3.1 and upon compliance with the conditions set
forth below in this Article. Any such election shall be evidenced by a Board
Resolution or in another manner specified as contemplated by Section 3.1 for
such Securities.


                                                                            -63-
<PAGE>

SECTION  13.2 DEFEASANCE AND DISCHARGE.

         Upon the Company's exercise of its option (if any) to have this Section
applied to any Securities or any series of Securities, as the case may be, the
Company shall be deemed to have been discharged from its obligations with
respect to such Securities as provided in this Section on and after the date the
conditions set forth in Section 13.4 are satisfied (hereinafter called
"Defeasance"). For this purpose, such Defeasance means that the Company shall be
deemed to have paid and discharged the entire indebtedness represented by such
Securities and to have satisfied all its other obligations under such Securities
and this Indenture insofar as such Securities are concerned (and the Trustee, at
the expense of the Company, shall execute proper instruments acknowledging the
same), subject to the following which shall survive until otherwise terminated
or discharged hereunder:

                  (1)      the rights of Holders of such Securities to receive,
         solely from the trust fund described in Section 13.4 and as more fully
         set forth in such Section, payments in respect of the principal of and
         any premium and interest on such Securities when payments are due,

                  (2)      the Company's obligations with respect to such
         Securities under Sections 3.4, 3.5, 3.6, 10.2 and 10.3, and, if
         applicable, Article 14,

                  (3)      the rights, powers, trusts, duties and immunities of
         the Trustee hereunder, and

                  (4)      this Article.

         Subject to compliance with this Article, the Company may exercise its
option (if any) to have this Section applied to any Securities notwithstanding
the prior exercise of its option (if any) to have Section 13.3 applied to such
Securities.

SECTION  13.3 COVENANT DEFEASANCE.

         Upon the Company's exercise of its option (if any) to have this Section
applied to any Securities or any series of Securities, as the case may be,

                  (1)      the Company shall be released from its obligations
         under Sections 10.6 and 10.7 and any covenants provided pursuant to
         Sections 3.1(19), 9.1(2) or 9.1(7) for the benefit of the Holders of
         such Securities and

                  (2)      the occurrence of any event specified in Section
         5.1(4) (with respect to any of Sections 10.6 and 10.7 and any such
         covenants provided pursuant to Section 3.1(19), 9.1(2) or 9.1(7)) and
         the occurrence of any other Event of Default specified pursuant to
         Section 3.1 shall be deemed not to be or result in an Event of Default,

in each case with respect to such Securities or any series of Securities as
provided in this Section on and after the date the conditions set forth in
Section 13.4 are satisfied (hereinafter called "Covenant Defeasance"). For this
purpose, such Covenant Defeasance means that, with respect to such Securities,
the Company may omit to comply with and shall have no liability in respect of
any term,


                                                                            -64-
<PAGE>

condition or limitation set forth in any such specified Section (to the extent
so specified in the case of Section 5.1(4) and the occurrence of any Event of
Default specified pursuant to Section 3.1), whether directly or indirectly by
reason of any reference elsewhere herein to any such Section or by reason of any
reference in any such Section to any other provision herein or in any other
document, but the remainder of this Indenture and such Securities shall be
unaffected thereby.

SECTION  13.4 CONDITIONS TO DEFEASANCE OR COVENANT DEFEASANCE.

         The following shall be the conditions to the application of Section
13.2 or Section 13.3 to any Securities or any series of Securities, as the case
may be:

         (1)      The Company shall irrevocably have deposited or caused to be
deposited with the Trustee (or another trustee which satisfies the requirements
contemplated by Section 6.9 and agrees to comply with the provisions of this
Article applicable to it) as trust funds in trust for the purpose of making the
following payments, specifically pledged as security for, and dedicated solely
to, the benefits of the Holders of such Securities,

                  (A)      in the case of Securities of a series denominated in
         currency of the United States of America,

                           (i)      cash in currency of the United States of
                  America in an amount, or

                           (ii)     U.S. Government Obligations which through
                  the scheduled payment of principal and interest in respect
                  thereof in accordance with their terms will provide, not later
                  than one day before the due date of any payment, an amount in
                  cash, or

                           (iii)    a combination thereof, or

                  (B)      in the case of Securities of a series denominated in
         currency other than that of the United States of America,

                           (i)      cash in the currency in which such series of
                  Securities is denominated in an amount, or

                           (ii)     Foreign Government Obligations which through
                  the scheduled payment of principal and interest in respect
                  thereof in accordance with their terms will provide, not later
                  than one day before the due date of any payment, an amount in
                  cash, or

                           (iii)    a combination thereof,

in each case sufficient, in the opinion of a nationally recognized firm of
independent public accountants expressed in a written certification thereof
delivered to the Trustee, to pay and discharge, and which shall be applied by
the Trustee (or any such other qualifying trustee) to


                                                                            -65-
<PAGE>

pay and discharge, the principal of and any premium and interest on such
Securities on the respective Stated Maturities, in accordance with the terms of
this Indenture and such Securities.

         (2)      For Securities denominated in United States dollars, in the
event of an election to have Section 13.2 apply to any Securities or any series
of Securities, as the case may be, the Company shall have delivered to the
Trustee an Opinion of Counsel stating that

                  (A)      the Company has received from, or there has been
         published by, the Internal Revenue Service a ruling or

                  (B)      since the date of this instrument, there has been a
         change in the applicable Federal income tax law,

in either case (A) or (B) to the effect that, and based thereon such opinion
shall confirm that, the Holders of such Securities will not recognize gain or
loss for Federal income tax purposes as a result of the deposit, Defeasance and
discharge to be effected with respect to such Securities and will be subject to
Federal income tax on the same amount, in the same manner and at the same times
as would be the case if such deposit, Defeasance and discharge were not to
occur.

         (3)      For Securities denominated in United States dollars, in the
event of an election to have Section 13.3 apply to any Securities or any series
of Securities, as the case may be, the Company shall have delivered to the
Trustee an Opinion of Counsel to the effect that the Holders of such Securities
will not recognize gain or loss for Federal income tax purposes as a result of
the deposit and Covenant Defeasance to be effected with respect to such
Securities and will be subject to Federal income tax on the same amount, in the
same manner and at the same times as would be the case if such deposit and
Covenant Defeasance were not to occur.

         (4)      The Company shall have delivered to the Trustee an Officers'
Certificate to the effect that neither such Securities nor any other Securities
of the same series, if then listed on any securities exchange, will be delisted
as a result of such deposit.

         (5)      No event which is, or after notice or lapse of time or both
would become, an Event of Default with respect to such Securities or any other
Securities shall have occurred and be continuing at the time of such deposit or,
with regard to any such event specified in Sections 5.1(5) and (6), at any time
on or prior to the 90th day after the date of such deposit (it being understood
that this condition shall not be deemed satisfied until after such 90th day).

         (6)      Such Defeasance or Covenant Defeasance shall not cause the
Trustee to have a conflicting interest within the meaning of the Trust Indenture
Act (assuming all Securities are in default within the meaning of such Act).


                                                                            -66-
<PAGE>

         (7)      Such Defeasance or Covenant Defeasance shall not result in a
breach or violation of, or constitute a default under, this Indenture or any
other agreement or instrument to which the Company is a party or by which it is
bound.

         (8)      Such Defeasance or Covenant Defeasance shall not result in the
trust arising from such deposit constituting an investment company within the
meaning of the Investment Company Act unless such trust shall be registered
under such Act or exempt from registration thereunder.

         (9)      The Company shall have delivered to the Trustee an Officers'
Certificate and an Opinion of Counsel, each stating that all conditions
precedent with respect to such Defeasance or Covenant Defeasance have been
complied with.

SECTION 13.5 DEPOSITED MONEY, U.S. GOVERNMENT OBLIGATIONS AND FOREIGN GOVERNMENT
OBLIGATIONS TO BE HELD IN TRUST; MISCELLANEOUS PROVISIONS.

         Subject to the provisions of the last paragraph of Section 10.3, all
money, U.S. Government Obligations and Foreign Government Obligations (including
the proceeds thereof) deposited with the Trustee or other qualifying trustee
(solely for purposes of this Section and Section 13.6, the Trustee and any such
other trustee are referred to collectively as the "Trustee") pursuant to Section
13.4 in respect of any Securities shall be held in trust and applied by the
Trustee, in accordance with the provisions of such Securities and this
Indenture, to the payment, either directly or through any such Paying Agent
(including the Company acting as its own Paying Agent) as the Trustee may
determine, to the Holders of such Securities, of all sums due and to become due
thereon in respect of principal and any premium and interest, but money so held
in trust need not be segregated from other funds except to the extent required
by law. The Company shall pay and indemnify the Trustee against any tax, fee or
other charge imposed on or assessed against the U.S. Government Obligations or
Foreign Government Obligations deposited pursuant to Section 13.4 or the
principal and interest received in respect thereof other than any such tax, fee
or other charge which by law is for the account of the Holders of Outstanding
Securities. Anything in this Article to the contrary notwithstanding, the
Trustee shall deliver or pay to the Company from time to time upon Company
Request any money, U.S. Government Obligations or Foreign Government Obligations
held by it as provided in Section 13.4 with respect to any Securities which, in
the opinion of a nationally recognized firm of independent public accountants
expressed in a written certification thereof delivered to the Trustee, are in
excess of the amount thereof which would then be required to be deposited to
effect the Defeasance or Covenant Defeasance, as the case may be, with respect
to such Securities.

SECTION 13.6 REINSTATEMENT.

         If the Trustee or the Paying Agent is unable to apply any money in
accordance with this Article with respect to any Securities by reason of any
order or judgment of any court or governmental authority enjoining, restraining
or otherwise prohibiting such application, then the obligations under this
Indenture and such Securities from which the Company has been discharged or
released pursuant to Section 13.2 or 13.3 shall be revived and reinstated as
though no deposit had


                                                                            -67-
<PAGE>

occurred pursuant to this Article with respect to such Securities, until such
time as the Trustee or Paying Agent is permitted to apply all money held in
trust pursuant to Section 13.5 with respect to such Securities in accordance
with this Article; provided, however, that if the Company makes any payment of
principal of or any premium or interest on any such Security following such
reinstatement of its obligations, the Company shall be subrogated to the rights
(if any) of the Holders of such Securities to receive such payment from the
money so held in trust.

                                   ARTICLE 14

                            CONVERSION OF SECURITIES

SECTION 14.1 APPLICABILITY OF ARTICLE.

         The provisions of this Article shall be applicable to the Securities of
any series which are convertible into shares of Common Stock of the Company, and
the issuance of such shares of Common Stock upon the conversion of such
Securities, except as otherwise specified as contemplated by Section 3.1 for the
Securities of such series.

SECTION 14.2 EXERCISE OF CONVERSION PRIVILEGE.

         In order to exercise a conversion privilege, the Holder of a Security
of a series with such a privilege shall surrender such Security to the Company
at the office or agency maintained for that purpose pursuant to Section 10.2,
accompanied by a duly executed conversion notice to the Company substantially in
the form set forth in Section 2.6 stating that the Holder elects to convert such
Security or a specified portion thereof. Such notice shall also state, if
different from the name and address of such Holder, the name or names (with
address) in which the certificate or certificates for shares of Common Stock,
which shall be issuable on such conversion, shall be issued. Securities
surrendered for conversion shall (if so required by the Company or the Trustee)
be duly endorsed by or accompanied by instruments of transfer in forms
satisfactory to the Company and the Trustee duly executed by the Holder or its
attorney duly authorized in writing; and Securities so surrendered for
conversion (in whole or in part) during the period from the close of business on
any Regular Record Date to the opening of business on the next succeeding
Interest Payment Date (excluding Securities or portions thereof called for
redemption during the period beginning at the close of business on a Regular
Record Date and ending at the opening of business on the first Business Day
after the next succeeding Interest Payment Date, or if such Interest Payment
Date is not a Business Day, the second such Business Day) shall also be
accompanied by payment in funds acceptable to the Company of an amount equal to
the interest payable on such Interest Payment Date on the principal amount of
such Security then being converted, and such interest shall be payable to such
Holder notwithstanding the conversion of such Security, subject to the
provisions of Section 3.7 relating to the payment of Defaulted Interest by the
Company. As promptly as practicable after the receipt of such notice and of any
payment required pursuant to a Board Resolution and, subject to Section 3.3, set
forth, or determined in the manner provided, in an Officers' Certificate, or
established in one or more indentures supplemental hereto setting forth the
terms of such series of Security, and the surrender of such Security in
accordance with such reasonable regulations as the Company may


                                                                            -68-
<PAGE>

prescribe, the Company shall issue and shall deliver, at the office or agency at
which such Security is surrendered, to such Holder or on its written order, a
certificate or certificates for the number of full shares of Common Stock
issuable upon the conversion of such Security (or specified portion thereof), in
accordance with the provisions of such Board Resolution, Officers' Certificate
or supplemental indenture, and cash as provided therein in respect of any
fractional share of such Common Stock otherwise issuable upon such conversion.
Such conversion shall be deemed to have been effected immediately prior to the
close of business on the date on which such notice and such payment, if
required, shall have been received in proper order for conversion by the Company
and such Security shall have been surrendered as aforesaid (unless such Holder
shall have so surrendered such Security and shall have instructed the Company to
effect the conversion on a particular date following such surrender and such
Holder shall be entitled to convert such Security on such date, in which case
such conversion shall be deemed to be effected immediately prior to the close of
business on such date) and at such time the rights of the Holder of such
Security as such Security Holder shall cease and the person or persons in whose
name or names any certificate or certificates for shares of Common Stock of the
Company shall be issuable upon such conversion shall be deemed to have become
the Holder or Holders of record of the shares represented thereby. Except as set
forth above and subject to the final paragraph of Section 3.7, no payment or
adjustment shall be made upon any conversion on account of any interest accrued
on the Securities (or any part thereof) surrendered for conversion or on account
of any dividends on the Common Stock of the Company issued upon such conversion.
In the case of any Security which is converted in part only, upon such
conversion the Company shall execute and the Trustee shall authenticate and
deliver to or on the order of the Holder thereof, at the expense of the Company,
a new Security or Securities of the same series, of authorized denominations, in
aggregate principal amount equal to the unconverted portion of such Security.

SECTION 14.3 NO FRACTIONAL SHARES.

         No fractional share of Common Stock of the Company shall be issued upon
conversions of Securities of any series. If more than one Security shall be
surrendered for conversion at one time by the same Holder, the number of full
shares which shall be issuable upon conversion shall be computed on the basis of
the aggregate principal amount of the Securities (or specified portions thereof
to the extent permitted hereby) so surrendered. If, except for the provisions of
this Section 14.3, any Holder of a Security or Securities would be entitled to a
fractional share of Common Stock of the Company upon the conversion of such
Security or Securities, or specified portions thereof, the Company shall pay to
such Holder an amount in cash equal to the current market value of such
fractional share computed, (i) if such Common Stock is listed or admitted to
unlisted trading privileges on a national securities exchange or market, on the
basis of the last reported sale price regular way on such exchange or market on
the last trading day prior to the date of conversion upon which such a sale
shall have been effected, or (ii) if such Common Stock is not at the time so
listed or admitted to unlisted trading privileges on a national securities
exchange or market, on the basis of the average of the bid and asked prices of
such Common Stock in the over-the-counter market, on the last trading day prior
to the date of conversion, as reported by the National Quotation Bureau,
Incorporated or similar organization if the National Quotation Bureau,
Incorporated is no longer reporting such information, or if not so available,
the fair market price as


                                                                            -69-
<PAGE>

determined by the Board of Directors. For purposes of this Section, "trading
day" shall mean each Monday, Tuesday, Wednesday, Thursday and Friday other than
any day on which the Common Stock is not traded on the Nasdaq National Market,
or if the Common Stock is not traded on the Nasdaq National Market, on the
principal exchange or market on which the Common Stock is traded or quoted.

SECTION 14.4 ADJUSTMENT OF CONVERSION PRICE.

         The conversion price of Securities of any series that is convertible
into Common Stock of the Company shall be adjusted for any stock dividends,
stock splits, reclassifications, combinations or similar transactions in
accordance with the terms of the supplemental indenture or Board Resolutions
setting forth the terms of the Securities of such series. Whenever the
conversion price is adjusted, the Company shall compute the adjusted conversion
price in accordance with terms of the applicable Board Resolution or
supplemental indenture and shall prepare an Officers' Certificate setting forth
the adjusted conversion price and showing in reasonable detail the facts upon
which such adjustment is based, and such certificate shall forthwith be filed at
each office or agency maintained for the purpose of conversion of Securities
pursuant to Section 10.2 and, if different, with the Trustee. The Company shall
forthwith cause a notice setting forth the adjusted conversion price to be
mailed, first class postage prepaid, to each Holder of Securities of such series
at its address appearing on the Security Register and to any conversion agent
other than the Trustee.

SECTION 14.5 NOTICE OF CERTAIN CORPORATE ACTIONS.

         In case:

                  (1)      the Company shall declare a dividend (or any other
         distribution) on its Common Stock payable otherwise than in cash out of
         its retained earnings (other than a dividend for which approval of any
         shareholders of the Company is required) that would require an
         adjustment pursuant to Section 14.4; or

                  (2)      the Company shall authorize the granting to all or
         substantially all of the holders of its Common Stock of rights, options
         or warrants to subscribe for or purchase any shares of capital stock of
         any class or of any other rights (other than any such grant for which
         approval of any shareholders of the Company is required); or

                  (3)      of any reclassification of the Common Stock of the
         Company (other than a subdivision or combination of its outstanding
         shares of Common Stock, or of any consolidation, merger or share
         exchange to which the Company is a party and for which approval of any
         shareholders of the Company is required), or of the sale of all or
         substantially all of the assets of the Company; or

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


                                                                            -70-
<PAGE>

then the Company shall cause to be filed with the Trustee, and shall cause to be
mailed to all Holders at their last addresses as they shall appear in the
Security Register, at least 20 days (or 10 days in any case specified in clause
(1) or (2) above) prior to the applicable record date hereinafter specified, a
notice stating (i) the date on which a record is to be taken for the purpose of
such dividend, distribution, rights, options 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, rights, options or warrants are to be
determined, or (ii) the date on which such reclassification, consolidation,
merger, share exchange, sale, dissolution, liquidation or winding up is expected
to become effective, and the date as of which it is expected that holders of
Common Stock of record shall be entitled to exchange their shares of Common
Stock for securities, cash or other property deliverable upon such
reclassification, consolidation, merger, share exchange, sale, dissolution,
liquidation or winding up. If at any time the Trustee shall not be the
conversion agent, a copy of such notice shall also forthwith be filed by the
Company with the Trustee.

SECTION 14.6 RESERVATION OF SHARES OF COMMON STOCK.

         The Company shall at all times reserve and keep available, free from
preemptive rights, out of its authorized but unissued Common Stock, for the
purpose of effecting the conversion of Securities, the full number of shares of
Common Stock of the Company then issuable upon the conversion of all outstanding
Securities of any series that has conversion rights.

SECTION 14.7 PAYMENT OF CERTAIN TAXES UPON CONVERSION.

         Except as provided in the next sentence, the Company will pay any and
all taxes that may be payable in respect of the issue or delivery of shares of
its Common Stock on conversion of Securities pursuant hereto. 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 shares of its Common Stock in a
name other than that of the Holder of the Security or Securities to be
converted, and no such issue or delivery shall be made unless and until the
person requesting such issue has paid to the Company the amount of any such tax,
or has established, to the satisfaction of the Company, that such tax has been
paid.

SECTION 14.8 NONASSESSABILITY.

         The Company covenants that all shares of its Common Stock that may be
issued upon conversion of Securities will upon issue in accordance with the
terms hereof be duly and validly issued and fully paid and nonassessable.

SECTION 14.9 PROVISION IN CASE OF CONSOLIDATION, MERGER OR SALE OF ASSETS.

         In case of any consolidation or merger of the Company with or into any
other Person, any merger of another Person with or into the Company (other than
a merger which does not result in any reclassification, conversion, exchange or
cancellation of outstanding shares of Common Stock of the Company) or any
conveyance, sale, transfer or lease of all or substantially all of the assets of
the Company, the Person formed by such consolidation or resulting from such
merger or which acquires


                                                                            -71-
<PAGE>

such assets, as the case may be, shall execute and deliver to the Trustee a
supplemental indenture providing that the Holder of each Security of a series
then Outstanding that is convertible into Common Stock of the Company shall have
the right thereafter (which right shall be the exclusive conversion right
thereafter available to said Holder), during the period such Security shall be
convertible, to convert such Security only into the kind and amount of
securities, cash and other property receivable upon such consolidation, merger,
conveyance, sale, transfer or lease by a holder of the number of shares of
Common Stock of the Company into which such Security might have been converted
immediately prior to such consolidation, merger, conveyance, sale, transfer or
lease, assuming such holder of Common Stock of the Company (i) is not a Person
with which the Company consolidated or merged with or into or which merged into
or with the Company or to which such conveyance, sale, transfer or lease was
made, as the case may be (a "Constituent Person"), or an Affiliate of a
Constituent Person and (ii) failed to exercise his rights of election, if any,
as to the kind or amount of securities, cash and other property receivable upon
such consolidation, merger, conveyance, sale, transfer or lease (provided that
if the kind or amount of securities, cash and other property receivable upon
such consolidation, merger, conveyance, sale, transfer, or lease is not the same
for each share of Common Stock of the Company held immediately prior to such
consolidation, merger, conveyance, sale, transfer or lease by others than a
Constituent Person or an Affiliate thereof and in respect of which such rights
of election shall not have been exercised ("Non-electing Share"), then for the
purpose of this Section 14.9 the kind and amount of securities, cash and other
property receivable upon such consolidation, merger, conveyance, sale, transfer
or lease by the holders of 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, for
events subsequent to the effective date of such supplemental indenture, shall be
as nearly equivalent as may be practicable to the adjustments provided for in
this Article or in accordance with the terms of the supplemental indenture or
Board Resolutions setting forth the terms of such adjustments. The above
provisions of this Section 14.9 shall similarly apply to successive
consolidations, mergers, conveyances, sales, transfers or leases. Notice of the
execution of such a supplemental indenture shall be given by the Company to the
Holder of each Security of a series that is convertible into Common Stock of the
Company as provided in Section 1.6 promptly upon such execution. Neither the
Trustee nor any conversion agent, if any, shall be under any responsibility to
determine the correctness of any provisions contained in any such supplemental
indenture relating either to the kind or amount of shares of stock or other
securities or property or cash receivable by Holders of Securities of a series
convertible into Common Stock of the Company upon the conversion of their
Securities after any such consolidation, merger, conveyance, transfer, sale or
lease or to any such adjustment, but may accept as conclusive evidence of the
correctness of any such provisions, and shall be protected in relying upon, an
Opinion of Counsel with respect thereto, which the Company shall cause to be
furnished to the Trustee upon request.

SECTION 14.10 DUTIES OF TRUSTEE REGARDING CONVERSION.

         Neither the Trustee nor any conversion agent shall at any time be under
any duty or responsibility to any Holder of Securities of any series that is
convertible into Common Stock of the Company to determine whether any facts
exist which may require any adjustment of the conversion


                                                                            -72-
<PAGE>

price, or with respect to the nature or extent of any such adjustment when made,
or with respect to the method employed, whether herein or in any supplemental
indenture, any resolutions of the Board of Directors or written instrument
executed by one or more officers of the Company provided to be employed in
making the same. Neither the Trustee nor any conversion agent shall be
accountable with respect to the validity or value (or the kind or amount) of any
shares of Common Stock of the Company, or of any securities or property, which
may at any time be issued or delivered upon the conversion of any Securities and
neither the Trustee nor any conversion agent makes any representation with
respect thereto. Subject to the provisions of Section 6.1, neither the Trustee
nor any conversion agent shall be responsible for any failure of the Company to
issue, transfer or deliver any shares of its Common Stock or stock certificates
or other securities or property upon the surrender of any Security for the
purpose of conversion or to comply with any of the covenants of the Company
contained in this Article 14 or in the applicable supplemental indenture,
resolutions of the Board of Directors or written instrument executed by one or
more duly authorized officers of the Company.

SECTION 14.11 REPAYMENT OF CERTAIN FUNDS UPON CONVERSION.

         Any funds which at any time shall have been deposited by the Company or
on its behalf with the Trustee or any other paying agent for the purpose of
paying the principal of, and premium, if any, and interest, if any, on any of
the Securities (including, but not limited to, funds deposited for the sinking
fund referred to in Article 12 hereof and funds deposited pursuant to Article 13
hereof) and which shall not be required for such purposes because of the
conversion of such Securities as provided in this Article 14 shall after such
conversion be repaid to the Company by the Trustee upon the Company's written
request.

            [The remainder of this page is intentionally left blank.]


                                                                            -73-
<PAGE>

         IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be
duly executed as of the day and year first above written.

                                        CELL GENESYS, INC.


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

                                        Title:
                                               ---------------------------------


                                        ----------------------------------------
                                        as Trustee

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

                                        Title:
                                               ---------------------------------