Form of Debt Warrant Agreement            Exhibit 4.3


                             DEBT WARRANT AGREEMENT


                         dated as of ________ __, 200__


                                     between


                                     UBS AG


                                       and


                    [NAME OF WARRANT AGENT], as Warrant Agent



                                  Debt Warrants


                           Expiring ________ __, 200__

                                TABLE OF CONTENTS


                                                                                                  Page
                                                                                               
PARTIES......................................................................................      1
RECITALS.....................................................................................      1



                                    ARTICLE I

                         ISSUANCE OF WARRANTS AND FORM,
                      EXECUTION, DELIVERY AND REGISTRATION
                             OF WARRANT CERTIFICATES

Section 1.01.    The Warrants; Issuance of Warrants; Book-Entry Procedures; Successor
                   Depository...............................................................       2
Section 1.02.    Form; Denominations; Execution, Countersignature, Delivery and Dating of
                 Global Warrant Certificates.................................................      5
Section 1.03.    Definitive Warrant Certificates.............................................      7
Section 1.04.    Maintenance of Warrant Register; Registration of Transfers and Exchanges of
                   Global Warrant Certificates...............................................      9
Section 1.05.    Mutilated, Destroyed, Lost and Stolen Warrant Certificates..................     11
Section 1.06.    Cancellation of Warrants....................................................     13


                                   ARTICLE II

                EXERCISE PRICE, DURATION AND EXERCISE OF WARRANTS

Section 2.01.    Exercise Price..............................................................     14
Section 2.02.    Duration of Warrants; Method of Exercise;
                  Minimum [and Maximum] Exercise Amounts;
                 Notice of Exercise..........................................................     14
Section 2.03.    Exercise of Warrants........................................................     16
Section 2.04.    Designation of Agent for Receipt of Notice..................................     20




                                   ARTICLE III

                         OTHER PROVISIONS RELATING TO
                                RIGHTS OF HOLDERS

                                                                                               
Section 3.01.    Treatment of Holders........................................................     20
Section 3.02.    Holder or Owner of Warrant May Enforce Rights...............................     21


                                   ARTICLE IV

                          CONCERNING THE WARRANT AGENT

Section 4.01.    Warrant Agent...............................................................      2
Section 4.02.    Certain Duties of the Warrant Agent.........................................      2
Section 4.03.    Conditions of Warrant Agent's Obligations...................................      2
Section 4.04.    Compliance With Applicable Laws.............................................      5
Section 4.05.    Corporate Warrant Agent Required; Eligibility...............................      6
Section 4.06.    Resignation and Removal; Appointment of Successor...........................      6
Section 4.07.    Acceptance of Appointment by Successor......................................      8
Section 4.08.    Merger, Conversion, Consolidation or Succession to Business.................      8


                                    ARTICLE V

                CONSOLIDATION, MERGER, SALE, LEASE OR CONVEYANCE

Section 5.01.    Consolidations and Mergers of the Corporation and Sales, Leases and
                 Conveyances Permitted Subject to Certain Conditions.........................     29


                         ARTICLE VI

                   SUPPLEMENTAL AGREEMENTS

Section 6.01.    Amendment of Debt Warrant Agreement.........................................     30
Section 6.02.    Form of Approval of Supplemental Agreements by Owners or Holders............     32
Section 6.03.    Effect of Supplemental Agreements...........................................     32
Section 6.04.    Reference in Warrants to Supplemental Agreements............................     33




                                   ARTICLE VII

                          COVENANTS OF THE CORPORATION
                                                                                               
Section 7.01.    Delivery of Prospectus......................................................     33
Section 7.02.    Governmental Approvals......................................................     33
Section 7.03.    Delivery of Warrant Debt Securities.........................................     34
Section 7.04.    Maintenance of Office or Agency; Unclaimed Moneys...........................     34
Section 7.05.    Corporate Existence.........................................................     35


                                  ARTICLE VIII

                                  MISCELLANEOUS

Section 8.01.    Reopening of Issue of Warrants..............................................     35
Section 8.02.    Payment of Taxes............................................................     35
Section 8.03.    Notices and Demands to the Corporation and Warrant Agent....................     35
Section 8.04.    Addresses for Notices.......................................................     36
Section 8.05.    Notices to Owners and Holders...............................................     36
Section 8.05.    Governing Law...............................................................     36
Section 8.06.    Benefits of Debt Warrant Agreement..........................................     36
Section 8.07.    Successors and Assigns......................................................     37
Section 8.08.    Debt Warrant Agreement and Warrants Solely
                  Corporate Obligations .....................................................     37
Section 8.09.    Severability................................................................     37
Section 8.10.    Headings....................................................................     37
Section 8.11.    Counterparts................................................................     37
Section 8.12.    Inspection of Debt Warrant Agreement........................................     37




                                    EXHIBITS


              
Exhibit A        Form of Warrant Certificate
Exhibit B-1      Form of Exercise Notice from Depository Participant
Exhibit B-2      Form of Exercise Notice from Holder of Definitive
                 Warrant Certificate
Exhibit C        Form of Rejection Notice
Exhibit D        Form of Confirmation of Exercise


                             DEBT WARRANT AGREEMENT

                  DEBT WARRANT AGREEMENT, dated as of ________ __, 200__ (as
modified, amended or supplemented, this "Agreement"), between UBS AG, a
corporation organized and existing under the laws of Switzerland (the
"Corporation"), and [NAME OF WARRANT AGENT], a [banking association]
[corporation] organized and existing under the laws of ______________, as
Warrant Agent (the "Warrant Agent").

                              W I T N E S S E T H:

                  WHEREAS, the Corporation has entered into an Indenture, [dated
as of _______, 200__(the "Indenture"), between the Corporation and the
[TRUSTEE], providing for the issuance from time to time of its unsecured and
[unsubordinated] [subordinated] debentures, notes or other evidences of [senior]
[subordinated] indebtedness, to be issued in one or more series as provided in
the Indenture;

                  WHEREAS, the Corporation proposes to sell [[title of Debt
Securities being offered (if Debt Securities and Warrants are to be offered)]
(the "Offered Debt Securities") with] warrants (each, a "Warrant") representing
the right to purchase [title of Debt Securities purchasable through exercise of
Warrants] the "Warrant Debt Securities"); and

                  WHEREAS, the Corporation desires the Warrant Agent to act on
behalf of the Corporation, and the Warrant Agent is willing so to act, in
connection with the issuance, transfer, exchange, exercise and cancellation of
the [Offered Debt Securities and the] Warrants, and the Corporation desires to
set forth herein, among other things, the provisions of the Warrants and the
terms and conditions under which they may be issued, transferred, exchanged,
exercised and canceled;

                  NOW, THEREFORE, in consideration of the premises and of the
mutual agreements herein contained, the parties hereto agree as follows:



                                    ARTICLE I

                         ISSUANCE OF WARRANTS AND FORM,
                      EXECUTION, DELIVERY AND REGISTRATION
                             OF WARRANT CERTIFICATES

                  Section 1.01. The Warrants; Issuance of Warrants; Book-Entry
Procedures; Successor Depository. (a) Each Warrant shall represent the right,
subject to the provisions contained herein and therein, to purchase Warrant Debt
Securities in the aggregate principal amount of $_____________ at the Exercise
Price set forth in Section 2.01. [If Debt Securities and Warrants are to be
offered together -- Warrants shall [initially] be issued in units with the
Offered Debt Securities and shall not be separately transferable [before
_____________, 19__ (the "Detachable Date")]. Each such unit shall consist of
$_____ aggregate principal amount of the Offered Debt Securities and _______
Warrants.] No Warrant shall entitle any registered holder thereof (each, a
"Holder") or any Owner (as defined in Section 1.01(c)) to any of the rights of a
registered holder or owner of the Warrant Debt Securities, including, without
limitation, the right to receive the payment of principal of, premium, if any,
or interest, if any, on the Warrant Debt Securities or to enforce any of the
covenants in the Warrant Debt Securities or the Indenture[, except to the extent
that the consent of the Holders or Owners of Warrants is expressly required by
the terms of the Warrant Debt Securities for certain modifications of the
Warrant Debt Securities]. [No amendment or modification of the Indenture or the
forms of the Warrant Debt Securities that would adversely affect the rights of
the Holders or Owners of Warrants shall be made prior to the issuance of any
Warrant Debt Securities without the written consent of the Holders or Owners of
Warrants representing the right to purchase at least a majority of the maximum
principal amount of the Warrant Debt Securities that may be issued pursuant to
Warrants that may be issued pursuant to this Agreement.]

                  (b) The Warrants shall constitute direct, unconditional and
unsecured obligations of the Corporation.

                  (c) The Warrants shall initially be issued in book-entry form
and represented by one or more global certificates (each, a "Global Warrant
Certificate"). Owners of beneficial interests in a Global Warrant Certificate
(each, an "Owner") shall not be entitled to

                                      -2-

receive definitive certificates evidencing the Warrants; provided, however, that
the Corporation shall issue Warrants in definitive form (each, a "Definitive
Warrant Certificate", and with the Global Warrant Certificates, the "Warrant
Certificates") in exchange for a Global Warrant Certificate if (i) the
Depository (as defined in Section 1.01(d)) has notified the Corporation that it
is unwilling or unable to continue as Depository for such Global Warrant
Certificate or if at any time it has ceased to be a clearing agency registered
under the Securities Exchange Act of 1934, as amended, at a time when it is
required to be so registered in order to act as Depository, and a successor
Depository is not appointed by the Corporation within 90 days, (ii) the
Corporation at any time shall determine to have the Warrants represented by
Definitive Warrant Certificates and shall execute and deliver to the Warrant
Agent a written order signed in the name of the Corporation by its Chairman of
the Board, its Vice Chairman, its President or a Vice President, and by its
Treasurer, an Assistant Treasurer, its Secretary or an Assistant Secretary (each
such order, a "Corporation Order") stating that the Corporation wishes to issue
Warrants in definitive form in exchange for such Global Warrant Certificate, or
(iii) there shall have occurred and be continuing a default by the Corporation
in respect of its obligations with respect to the Warrants. In any such
instance, and in accordance with the provisions of this Agreement, each Owner
shall be entitled to have registered in its name the number of Warrants in
definitive form equivalent to such Owner's beneficial interest in such Global
Warrant Certificate and shall be entitled to physical delivery of Definitive
Warrant Certificates representing such Warrants by the Depository Participant or
Indirect Participant (each as defined in Section 1.01(d)) through which such
Owner's beneficial interest is reflected.

                  (d) Each Global Warrant Certificate shall initially be
registered in the name of, and the Holder of each Warrant represented by such
Global Warrant Certificate shall be, [The Depository Trust Company] or its agent
(the "Depository", which term shall include any nominee of the Depository and
any successor depository selected by the Corporation as provided in Section
1.01(e)), and shall be deposited with the Depository or its agent for credit to
the accounts of the Depository Participants as shown on the

                                      -3-

records of the Depository from time to time. The Warrant holdings of Depository
Participants shall be recorded on the books of the Depository. The Warrant
holdings of Indirect Participants and of Owners who are customers of Depository
Participants shall be reflected on the books and records of such Depository
Participants and shall not be known to the Warrant Agent, the Corporation or the
Depository. The Warrant holdings of Owners who are customers of Indirect
Participants shall be reflected on the books and records of such Indirect
Participants and shall not be known to the Warrant Agent, the Corporation, the
Depository Participants or the Depository. Neither the Corporation nor the
Warrant Agent shall have any responsibility or liability for any aspect of the
records relating to beneficial ownership interests in a Global Warrant
Certificate or for maintaining, supervising or reviewing any records relating to
any such beneficial ownership interest. As used herein, the term "Depository
Participant" shall include any participant in the Depository's system and, for
purposes of this Agreement, shall also mean any participant in the book-entry
system of any successor Depository. As used herein, the term "Indirect
Participant" shall include any other bank, securities dealer, trust company or
other Person (as defined below) that clears or maintains a custodial
relationship with a Depository Participant, either directly or indirectly. As
used herein, the term "Person" shall include any individual, corporation,
partnership, joint venture, association, joint-stock company, trust,
unincorporated organization or government or any agency or political subdivision
thereof.

                  (e) The Corporation may from time to time select a new Person
to act as Depository and, if such selection is made, the Corporation shall
promptly give the Warrant Agent and the existing Depository notice to such
effect identifying the new Depository. As promptly as practicable thereafter,
the Depository shall deliver each Global Warrant Certificate then held by it to
the Warrant Agent, and the Warrant Agent shall register the transfer of such
Global Warrant Certificate to the new Depository as provided in Section 1.04.
Appropriate changes may be made in each Global Warrant Certificate, and in the
notice of exercise and the related notices delivered in connection with an
exercise or deemed exercise of Warrants to reflect the selection of the new
Depository.

                                      -4-

                  Section 1.02. Form; Denominations; Execution,
Countersignature, Delivery and Dating of Global Warrant Certificates. (a) At any
time and from time to time after the execution and delivery of this Agreement,
the Corporation may deliver one or more Global Warrant Certificates, each
representing any integral number of Warrants [not exceeding ________________
Warrants originally issued,] executed by the Corporation as set forth in Section
1.02(b), to the Warrant Agent for countersignature, together with a Corporation
Order for the countersignature and delivery of such Warrants, and the Warrant
Agent shall manually countersign and deliver such Warrants in accordance with
such Corporation Order. During such time as Warrants shall be represented by
Global Warrant Certificates, the Corporation may issue additional Warrants in
accordance with the terms of this Agreement either by issuing an additional
Global Warrant Certificate or by issuing a new Global Warrant Certificate in
exchange for the existing Global Warrant Certificate, provided that any such
exchange shall conform to the requirements set forth in Section 1.04(f).

                  (b) Each Global Warrant Certificate, whenever issued, shall be
in registered form substantially in the form of Exhibit A, with such appropriate
insertions, omissions, substitutions and other variations as are required or
permitted by this Agreement. Each Global Warrant Certificate shall be printed,
lithographed, typewritten, mimeographed or engraved on steel engraved borders or
otherwise reproduced in any other manner as may be approved by the officers
executing the same (such execution to be conclusive evidence of such approval)
and may have imprinted or otherwise reproduced thereon such letters, numbers or
other marks of identification or designation and such legends or endorsements as
the officers of the Corporation executing the same may approve (such execution
to be conclusive evidence of such approval) and that are not inconsistent with
the provisions of this Agreement, or as may be required to comply with any law
or with any rule or regulation made pursuant thereto, or with any rule or
regulation of any securities exchange on which the Warrants may be listed, or of
the Depository, or to conform to usage. Each Global Warrant Certificate shall be
signed on behalf of the Corporation by its Chairman of the Board, its Vice
Chairman, its President or one of its Vice Presidents, under its corporate seal
reproduced thereon and

                                      -5-

attested by its Secretary or one of its Assistant Secretaries. The signature of
any such officer on any Global Warrant Certificate may be either manual or
facsimile. Typographical and other minor errors or defects in any such
reproduction of the seal or any such signature shall not affect the validity or
enforceability of any Global Warrant Certificate that has been duly
countersigned and delivered by the Warrant Agent.

                  (c) No Global Warrant Certificate shall be entitled to any
benefit under this Agreement or be valid or obligatory for any purpose, and no
Warrant evidenced thereby shall be exercisable, unless such Global Warrant
Certificate has been countersigned by the Warrant Agent. Such signature by the
Warrant Agent upon any Global Warrant Certificate executed by the Corporation
shall be conclusive evidence, and the only evidence, that such Global Warrant
Certificate so countersigned has been duly issued hereunder.

                  (d) Any Global Warrant Certificate bearing the manual or
facsimile signatures of individuals who were at the time of such signature the
proper officers of the Corporation shall bind the Corporation, notwithstanding
that such individuals or any of them have ceased to hold such offices prior to
the countersignature and delivery of such Global Warrant Certificate or did not
hold such offices at the date of such Global Warrant Certificate.

                  (e) Each Global Warrant Certificate shall be dated the date of
its countersignature.

                  Section 1.03. Definitive Warrant Certificates. (a) Any
Definitive Warrant Certificate issued in accordance with Section 1.01(c),
whenever issued, shall be in registered form substantially in the form of
Exhibit A, with such appropriate insertions, omissions, substitutions and other
variations as are required or permitted by this Agreement or necessary or
desirable for individual Definitive Warrant Certificates, provided that each
such Definitive Warrant Certificate shall have imprinted on the reverse thereof
the Exercise Notice substantially in the form of Exhibit B-2. Each Definitive
Warrant Certificate may represent any integral number of Warrants [not exceeding
________________ Warrants originally issued], shall be printed, lithographed,
typewritten, mimeographed

                                      -6-

or engraved on steel engraved borders or otherwise reproduced in any other
manner as may be approved by the officers executing the same (such execution to
be conclusive evidence of such approval), and may have imprinted or otherwise
reproduced thereon such letters, numbers or other marks of identification or
designation and such legends or endorsements as the officers of the Corporation
executing the same may approve (such execution to be conclusive evidence of such
approval) and that are not inconsistent with the provisions of this Agreement,
or as may be required to comply with any law or with any rule or regulation made
pursuant thereto, or with any rule or regulation of any securities exchange on
which the Warrants may be listed, or of the Depository, or to conform to usage.
Each Definitive Warrant Certificate shall be signed on behalf of the Corporation
upon the same conditions, in substantially the same manner and with the same
effect as set forth in Section 1.02 with respect to Global Warrant Certificates.

                  (b) Each Definitive Warrant Certificate, when so signed on
behalf of the Corporation, shall be delivered to the Warrant Agent together with
a Corporation Order for the countersignature and delivery of such Warrants, and
the Warrant Agent shall manually countersign and deliver such Warrants in
accordance with such Corporation Order upon the same conditions, in
substantially the same manner and with the same effect as set forth in Section
1.02 with respect to Global Warrant Certificates. Each Definitive Warrant
Certificate shall be dated the date of its countersignature.

                  (c) No Definitive Warrant Certificate shall be entitled to any
benefit under this Agreement or be valid or obligatory for any purpose, and no
Warrant evidenced thereby shall be exercisable, unless such Definitive Warrant
Certificate has been countersigned by the Warrant Agent. Such signature by the
Warrant Agent upon any Definitive Warrant Certificate executed by the
Corporation shall be conclusive evidence, and the only evidence, that such
Definitive Warrant Certificate so countersigned has been duly issued hereunder.

                  (d) Any Definitive Warrant Certificate bearing the manual or
facsimile signatures of individuals who were at the time of such signature the
proper officers of the


                                      -7-

Corporation shall bind the Corporation, notwithstanding that such individuals or
any of them have ceased to hold such offices prior to the countersignature and
delivery of such Definitive Warrant Certificate or did not hold such offices at
the date of such Definitive Warrant Certificate.

                  (e) Definitive Warrant Certificates delivered in exchange for
a Global Warrant Certificate shall be registered in such names and addresses
(including tax identification numbers) and in such denominations as shall be
requested in writing by the Depository or its nominee in whose name such Global
Warrant Certificate is registered, upon written certification to the Corporation
and the Warrant Agent, in form satisfactory to each of them, of the existing
beneficial ownership interests in such Global Warrant Certificate.

                  (f) The Holder of any Warrant represented by a Definitive
Warrant Certificate shall be [if Debt Securities and Warrants that are not
immediately detachable are offered -- , prior to the Detachable Date, the Person
in whose name the Offered Debt Security to which such Warrant Certificate was
initially attached shall be registered upon the register relating to such
Offered Debt Securities and, after such Detachable Date,] the Person in whose
name such Definitive Warrant Certificate is registered in the Warrant Register
(as defined in Section 1.04) at such time. [If Offered Debt Securities and
Warrants that are not immediately detachable are offered -- Prior to the
Detachable Date, the Corporation shall, or shall cause the registrar of the
Offered Debt Securities to, make available to the Warrant Agent such information
as may be necessary to permit the Warrant Agent to keep the Warrant Register up
to date regarding Holders of the Offered Debt Securities.]

                  Section 1.04. Maintenance of Warrant Register; Registration of
Transfers and Exchanges of Global Warrant Certificates. (a) [If Offered Debt
Securities and Warrants that are not immediately detachable are offered -- From
and after the Detachable Date,] the Corporation shall cause to be kept at the
Warrant Agent Office (as defined in Section 1.04(b)) a register (the "Warrant
Register"), which may be maintained electronically and in which, subject to such
reasonable regulations as it may prescribe, the Corporation shall provide for
the registration and registration of transfer, exchange, exercise and


                                      -8-

cancellation of Warrants. The Warrant Agent is hereby appointed "Warrant
Registrar" for the purpose of registering Warrant Certificates and transfers and
exchanges of Warrant Certificates as herein provided.

                  (b) [If Offered Debt Securities and Warrants that are not
immediately detachable are offered -- Prior to the Detachable Date, a Warrant
Certificate may be exchanged or transferred only together with the Offered Debt
Security to which such Warrant Certificate was initially attached, and only for
the purpose of effecting, or in conjunction with, an exchange or transfer of
such Offered Debt Security. Furthermore, on or prior to the Detachable Date,
each transfer of an Offered Debt Security on the register of the Offered Debt
Securities shall operate also to transfer the Warrant Certificate or
Certificates to which such Offered Debt Security was initially attached. From
and after the Detachable Date, a] [If Offered Debt Securities and Warrants that
are immediately detachable are offered -- A] Warrant Certificate may be
transferred at the option of the Holder thereof upon surrender of such Warrant
Certificate at the office or agency of the Warrant Agent maintained for the
purpose of transferring, exchanging, exercising and canceling the Warrants,
which [shall be south of Chambers Street in the Borough of Manhattan, The City
of New York] (the "Warrant Agent Office"), and which is, on the date of this
Agreement, _______________________, New York, New York, _____, Attention:
[Corporate Trust Department], or at the office of any successor Warrant Agent as
provided in Article IV. Upon any such registration of transfer, the Corporation
shall execute, and the Warrant Agent shall countersign and deliver, as provided
in Section 1.02 or 1.03, as the case may be, in the name of the designated
transferee a new Global Warrant Certificate or Definitive Warrant Certificate,
as the case may be, of like tenor, of any authorized denomination and
representing in the aggregate a like number of unexercised Warrants as evidenced
by such Warrant Certificate at the time of such registration of transfer, and
bearing a number not contemporaneously outstanding.

                  (c) A Warrant Certificate may be exchanged at the option of
the Holder thereof for other Global Warrant Certificates or Definitive Warrant
Certificates, as the case may be, of like tenor, of any authorized denomination
and representing in the aggregate a like number of

                                      -9-

unexercised Warrants, upon surrender of such Warrant Certificate at the Warrant
Agent Office. Whenever any Warrant Certificate is so surrendered for exchange,
the Corporation shall execute, and the Warrant Agent shall countersign and
deliver, as provided in Section 1.02 or 1.03, as the case may be, the Global
Warrant Certificates or Definitive Warrant Certificates, as the case may be,
that the Holder of such exchanged Warrant Certificate is entitled to receive and
bearing a number not contemporaneously outstanding.

                  (d) Any Warrant Certificate presented or surrendered for
registration of transfer or for exchange shall be duly endorsed or accompanied
by a written instrument or instruments of transfer in form satisfactory to the
Warrant Agent and the Corporation, duly signed by the registered Holder thereof
or by the duly appointed legal representative thereof or by a duly authorized
attorney, such signature to be guaranteed by a bank or trust company, by a
broker or dealer that is a member of the National Association of Securities
Dealers, Inc. or by a member of a national securities exchange.

                  (e) Except as otherwise provided herein or in a Global Warrant
Certificate, the Warrant Agent shall register the transfer of such Global
Warrant Certificate on the records of the Warrant Agent only to the Depository,
to a nominee of the Depository, to a successor Depository or to a nominee of the
successor Depository.

                  (f) A Global Warrant Certificate may be exchanged for a new
Global Warrant Certificate to reflect the issuance by the Corporation of
additional Warrants [; provided, however, that in no event shall the number of
Warrants represented by any Global Warrant Certificate exceed
___________________ originally issued]. To effect such an exchange, the
Corporation shall deliver to the Warrant Agent a new Global Warrant Certificate
duly executed on behalf of the Corporation as provided in Section 1.02, together
with a Corporation Order for the countersignature and delivery of such Warrants.
The Warrant Agent shall countersign such new Global Warrant Certificate as
provided in Section 1.02 and in accordance with such Corporation Order, and
shall deliver such new Global Warrant Certificate to the Depository in exchange
for, and upon receipt of, the Global Warrant Certificate


                                      -10-

then held by the Depository. The Warrant Agent shall cancel the Global Warrant
Certificate delivered to it by the Depository and return the canceled Global
Warrant Certificate to the Corporation.

                  (g) All Warrant Certificates issued upon any registration of
transfer or exchange of Global Warrant Certificates or Definitive Warrant
Certificates, as the case may be, shall be valid obligations of the Corporation,
evidencing the same obligations of the Corporation and entitled to the same
benefits under this Agreement, as the Warrant Certificates surrendered upon such
registration of transfer or exchange. The Warrant Agent shall not be required to
effect any exchange or transfer that would result in the issuance of a Warrant
Certificate evidencing a fraction of a Warrant or a number of full Warrants and
a fraction of a Warrant.

                  (h) No service charge shall be made for any registration of
transfer or exchange of Warrant Certificates, but the Corporation may require
payment of a sum sufficient to cover any stamp or other tax or other
governmental charge that may be imposed in connection with any such transfer or
exchange.

                  Section 1.05. Mutilated, Destroyed, Lost and Stolen Warrant
Certificates. (a) If any mutilated Warrant Certificate is surrendered to the
Warrant Agent, the Corporation shall execute, and the Warrant Agent shall
countersign and deliver in exchange therefor, as provided in Section 1.02 or
1.03, as the case may be, a new Warrant Certificate of like tenor representing a
like number of unexercised Warrants and bearing a number not contemporaneously
outstanding.

                  (b) If there shall be delivered by a Holder of a Warrant
Certificate to the Corporation and the Warrant Agent (i) evidence to their
satisfaction of the destruction, loss or theft of any Warrant Certificate, (ii)
such security or indemnity as may be required by them to save each of them and
any agent of either of them harmless, and (iii) funds sufficient to cover any
cost or expense to the Corporation (including any fees charged by the Warrant
Agent) relating to the issuance of a new Warrant Certificate, then, in the
absence of notice to the Corporation or the Warrant Agent that such Warrant


                                      -11-

Certificate has been acquired by a bona fide purchaser, the Corporation shall
execute, and the Warrant Agent shall countersign and deliver, as provided in
Section 1.02 or 1.03, as the case may be, in lieu of any such destroyed, lost or
stolen Warrant Certificate, a new Warrant Certificate of like tenor representing
a like number of unexercised Warrants and bearing a number not contemporaneously
outstanding.

                  (c) If the Warrants evidenced by any such mutilated,
destroyed, lost or stolen Warrant Certificate have been exercised, or have been
or are about to be deemed to be exercised, the Corporation in its discretion
may, instead of issuing a new Warrant Certificate, treat the same as if it had
received written irrevocable notice of exercise in good form in respect thereof,
as provided herein.

                  (d) Upon the issuance of any new Warrant Certificate under
this Section, the Corporation 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 Warrant
Agent) connected therewith.

                  (e) Every new Warrant Certificate issued pursuant to this
Section 1.05 in lieu of any mutilated, destroyed, lost or stolen Warrant
Certificate shall constitute an original additional contractual obligation of
the Corporation, whether or not the mutilated, destroyed, lost or stolen Warrant
Certificate shall be at any time enforceable by anyone, and shall be entitled to
all the benefits of this Agreement equally and proportionately with any and all
other Warrant Certificates duly issued hereunder.

                  (f) The provisions of this Section 1.05 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 Warrant
Certificates.

                  Section 1.06. Cancellation of Warrants. (a) If the Corporation
shall purchase or otherwise acquire Warrants represented by a Global Warrant
Certificate, such Warrants may, at the option of the Corporation and upon


                                      -12-

notification to the Warrant Agent, be surrendered free through a Depository
Participant for credit to the Warrant Account (as defined in Section 2.01(b))
and if so credited, the Warrant Agent shall promptly note the cancellation of
such Warrants by notation on the records of the Warrant Agent and on the Warrant
Register.

                  (b) When all of the Warrants represented by any Global Warrant
Certificate have been exercised by the Owner thereof, automatically exercised or
otherwise canceled, and upon receipt of the same by the Warrant Agent, the
Warrant Agent shall promptly cancel such Global Warrant Certificate.

                  (c) The Corporation may at any time deliver to the Warrant
Agent for cancellation any Definitive Warrant Certificates previously
countersigned and delivered hereunder that the Corporation may have acquired in
any manner whatsoever, and the Warrant Agent shall promptly cancel all
Definitive Warrant Certificates so delivered.

                  (d) All Warrant Certificates surrendered for exercise,
registration of transfer or exchange or cancellation, if surrendered to any
Person other than the Warrant Agent, shall be delivered to the Warrant Agent,
and the Warrant Agent shall promptly cancel all such Warrant Certificates and
all other Warrant Certificates surrendered to it for exercise, registration of
transfer or exchange or cancellation.

                  (e) No Warrant Certificate shall be countersigned in lieu of
or in exchange for any Warrant Certificate canceled as provided in this Section
1.06 except as expressly permitted by this Agreement. All canceled Warrant
Certificates held by the Warrant Agent shall be destroyed by it unless by
written order the Corporation requests their return to it.



                                   ARTICLE II

                EXERCISE PRICE, DURATION AND EXERCISE OF WARRANTS

                  Section 2.01. Exercise Price. [During the period from ________
__, 200__ through and including ________ __, 200__,] the exercise price of each
Warrant


                                      -13-

shall be [$_______] [____% of the principal amount of the Warrant Debt
Securities subject to such Warrant] plus [accrued amortization, if any, of the
original issue discount of the Warrant Debt Securities] [accrued interest, if
any, from the most recent date from which interest shall have been paid on the
Warrant Debt Securities or, if no interest shall have been paid on the Warrant
Debt Securities, from ________ __, 200__]. [During the period from ________ __,
200__ through and including ________ __, 200__, the exercise price of each
Warrant shall be [$_______] [____% of the principal amount of the Warrant Debt
Securities subject to such Warrant] plus [accrued amortization, if any, of the
original issue discount of the Warrant Debt Securities] [accrued interest, if
any, from the most recent date from which interest shall have been paid on the
Warrant Debt Securities or, if no interest shall have been paid on the Warrant
Debt Securities, from ________ __, 200__].] [In each case, the original issue
discount of $_______ for each $1,000 principal amount of Warrant Debt Securities
shall be amortized at a ___% annual rate, computed on a[n] [semi-]annual basis
[using a 360-day year consisting of twelve 30-day months].] The exercise price
of each Warrant `as set forth above is referred to in this Agreement as the
"Exercise Price."

                  Section 2.02. Duration of Warrants; Method of Exercise;
Minimum [and Maximum] Exercise Amounts; Notice of Exercise. (a) Subject to the
limitations described herein, each Warrant may be exercised in whole but not in
part on any New York Business Day (as defined in Section 2.02(f)) from [its date
of issuance (specify other date if applicable)] until [3:00 P.M.], New York City
time, on ________ __, 200__, or, if such date is not a New York Business Day, on
the next succeeding New York Business Day (the "Expiration Date"). Each Warrant
not exercised at or before [3:00 P.M.], New York City time, on the Expiration
Date shall become void, and all rights of the Owner or Holder of such Warrant
under this Agreement or otherwise shall cease.

                       (b) Each Warrant may be exercised by:

                       (i) in the case of any Warrant represented by a Global
         Warrant Certificate (each, a "Book-Entry Warrant"), (A) transfer of
         such Warrant on the records of the Depository free to the Warrant
         Agent's


                                      -14-

         Depository Participant account (entitled ____________________), or such
         other account of the Warrant Agent at the Depository as the Warrant
         Agent shall specify (the "Warrant Account"), (B) delivery to the
         Warrant Agent as provided in Section 2.02(d)(i)(C) of written notice
         (an "Exercise Notice") duly completed and executed by a Depository
         Participant acting on behalf of the Owner of such Warrant and (C)
         payment of the Exercise Price in U.S. dollars [in cash or by cashier's
         check or official bank check in New York Clearing House funds] [by bank
         wire transfer in immediately available funds] payable to the account of
         the Corporation; and

                       (ii) in the case of Warrants represented by a Definitive
         Warrant Certificate (each, a "Certificated Warrant"), (A) surrender of
         such Definitive Warrant Certificate to the Warrant Agent at the Warrant
         Agent Office, (B) delivery to the Warrant Agent as provided in Section
         2.02(d)(ii)(C) of an Exercise Notice duly completed and executed by the
         Holder of such Warrant and (C) payment of the Exercise Price in U.S.
         dollars [in cash or by cashier's check or official bank check in New
         York Clearing House funds] [by bank wire transfer in immediately
         available funds] payable to the account of the Corporation].

                  (c) Not fewer than [specify minimum exercise amount] [nor more
than [specify maximum exercise amount]] Warrants may be exercised by or on
behalf of any one Owner or, in the case of Certificated Warrants, any one Holder
at any one time, except that no such minimum [or maximum] exercise amount shall
apply in the case of the exercise of any Warrants on the Expiration Date.

                  (d) Each Exercise Notice shall be unconditional and
irrevocable and:

                       (i) in the case of any Book-Entry Warrant, shall (A) be
         in the form of Exhibit B-1 hereto, and (B) shall be sent to the Warrant
         Agent in writing at its address as set forth in such form of Exercise
         Notice or at such other address as the Warrant Agent may specify from
         time to time by notice given in accordance with Section 8.05; and

                                      -15-

                       (ii) in the case of any Certificated Warrant, shall (A)
         be in the form of Exhibit B-2 hereto and shall, unless otherwise agreed
         by the Corporation and the Warrant Agent, be set forth on the reverse
         of the Definitive Warrant Certificate representing such Certificated
         Warrant, and (B) shall be sent to the Warrant Agent in writing at its
         address as set forth in such form of Exercise Notice or at such other
         address as the Warrant Agent may specify from time to time by notice
         given in accordance with Section 8.05.

                  (e) Except as provided in Section 2.03(c), the Warrant Agent
and the Corporation shall be entitled to rely conclusively on any Exercise
Notice received by the Warrant Agent with no duty of inquiry by either of them.

                  (f) As used in this Agreement, "New York Business Day" means
any day other than a Saturday or Sunday or a day on which the [New York Stock
Exchange or American Stock Exchange (list any other relevant securities
exchanges)] is not open for securities trading or banking institutions generally
in The City of New York are authorized or required by law or executive order to
close.

                  Section 2.03. Exercise of Warrants. (a) Subject to Section
2.02(c)(ii), the exercise date (the "Exercise Date") for a Warrant shall be (i)
the New York Business Day on which the Warrant Agent receives delivery of such
Warrant to the Warrant Account, in the case of Book-Entry Warrants, or of the
Definitive Warrant Certificate representing such Warrant at the Warrant Agent
Office, in the case of Certificated Warrants, an Exercise Notice relating to
such Warrant in good order and payment of the Exercise Price in the manner
specified in Section 2.02(b), if such receipt occurs at or prior to [3:00] P.M.,
New York City time, on such New York Business Day, and (ii) otherwise the New
York Business Day next succeeding the day on which the Warrant Agent receives
such Warrant, the Exercise Price and such Exercise Notice, which next succeeding
New York Business Day shall be the day on which such Warrant, Exercise Price and
Exercise Notice shall be deemed to have been received. If any Exercise Notice,
the related Exercise Price or the Warrants to which such Exercise Notice relates
are received after [3:00] P.M., New York City time, on the Expiration Date, such
Exercise

                                      -16-

Notice shall be void and of no effect and shall be deemed not to have been
delivered.

                  (b) Following receipt of proper delivery of any Warrant, the
Exercise Price and the Exercise Notice related to such Warrant in accordance
with Section 2.02(b), the Warrant Agent shall:

                       (i) deposit all funds received by it in payment of the
         Exercise Price of such Warrant to the account of the Corporation
         maintained with it for such purpose (unless otherwise instructed in
         writing by the Corporation), and advise the Corporation by telephone
         and in writing, by facsimile transmission or otherwise, at the end of
         each day on which any such payment is received of the amount so
         deposited to its account;

                  (ii)(A) in the case of a Book-Entry Warrant, promptly
         determine whether such Exercise Notice has been duly completed and is
         in proper form and verify that the Person that executed such Exercise
         Notice is listed as a Depository Participant in the most recent
         published edition of the Depository's Eligible Corporate Securities
         Book (or the comparable publication of any successor Depository) and,
         if such Person is not listed therein, make reasonable efforts to obtain
         verbal verification from the Depository's Planning Department
         (telephone number 212-709-1000) (or the comparable department of a
         successor Depository) that such Person is a Depository Participant; and
         (B) in the case of a Certificated Warrant, promptly determine whether
         such Exercise Notice has been duly completed and is in proper form and
         whether the Definitive Warrant Certificate representing such Warrant is
         in proper form;

                  (iii)(A) in the case of a Book-Entry Warrant, if the Warrant
         Agent determines that such Exercise Notice has not been duly completed
         or is not in proper form, or is unable through the procedures described
         in clause (ii)(A) above to verify that the Person that submitted such
         Exercise Notice is a Depository Participant, then the Warrant Agent
         shall reject such Exercise Notice and shall send to the Depository
         Participant that submitted such Exercise


                                      -17-

         notice of rejection substantially in the form of Exhibit C hereto (a
         "Rejection Notice") and redeliver the Warrants to which such rejected
         Exercise Notice relates free through the facilities of the Depository
         to the account from which they were transferred; and (B) in the case of
         a Certificated Warrant, if the Warrant Agent determines that such
         Exercise Notice has not been duly completed or is not in proper form,
         or that the Definitive Warrant Certificate representing such Warrant is
         not in proper form, then the Warrant Agent shall reject such Exercise
         Notice and shall send a Rejection Notice to the Holder of such Warrants
         and return such Definitive Warrant Certificate to such Holder by first
         class mail at the expense of the Corporation;

                       (iv) by [5:00 P.M.], New York City time, on the New York
         Business Day on which such Exercise Notice is received (or deemed to
         have been received), notify the Corporation (and such other parties
         (not to exceed two) as the Corporation shall designate in writing) of
         (A) the total number of Warrants in respect of which Exercise Notices
         were received (or deemed to have been received) at or prior to [3:00
         P.M.], New York City time, on such date, (B) the number of such
         Exercise Notices that were rejected by the Warrant Agent pursuant to
         clause (iii) above and the aggregate number of Warrants to which such
         rejected Exercise Notices relate, and (C) the aggregate number of
         Warrants covered by Exercise Notices that have not been so rejected
         (the "Exercised Warrants");

                       (v) by [5:00 P.M.], New York City time, on the New York
         Business Day following the Exercise Date for such Exercised Warrants,
         send notice of confirmation of exercise in substantially the form of
         Exhibit D hereto to the appropriate Depository Participant or Holder,
         as the case may be; and

                       (vi) promptly deliver a copy of each Exercise Notice to
         the Corporation and advise the Corporation of such other matters
         relating to any of the Warrants covered thereby, whether or not they
         constitute Exercised Warrants, as the Corporation shall reasonably
         request.

                                      -18-

                  (c) At or before [3:00 P.M.], New York City time, on the
[fifth] New York Business Day following the Exercise Date for any Exercised
Warrant, the Corporation shall issue, and shall cause the Trustee to
authenticate and deliver, pursuant to the Indenture, in authorized
denominations, to or upon the order of the Holder of such Exercised Warrant, the
Warrant Debt Security or Warrant Debt Securities to which such Holder is
entitled, in fully registered form, registered in such name or names as may be
directed by such Holder in the Exercise Notice relating to such Exercised
Warrant.

                  (d) (i) The Warrant Agent shall cause its records, which may
be kept electronically, to be marked to reflect the reduction in the number of
Warrants evidenced by each Global Warrant Certificate by the number of such
Warrants in respect of which Warrant Debt Securities have been made available as
provided in Section 2.03(c) promptly after such payment has been made available.
In the absence of manifest error, the Warrant Agent's records shall be
conclusive evidence as to such matters.

                       (ii) If any Definitive Warrant Certificate shall be
         surrendered to the Warrant Agent for exercise of fewer than all the
         Warrants represented thereby, the Corporation shall execute, and the
         Warrant Agent shall countersign, as provided in Section 1.02 or 1.03,
         as the case may be, and deliver to the Holder of such Warrants by first
         class mail at the expense of the Corporation a new Definitive Warrant
         Certificate of like tenor representing all Warrants remaining
         unexercised after such exercise and bearing a number not
         contemporaneously outstanding.

                  (e) The Corporation shall not be required to pay any stamp or
other tax or other governmental charge required to be paid in connection with
any transfer involved in the issue of the Warrant Debt Securities, and the
Corporation shall not be required to issue or deliver any Warrant Debt
Securities until any such tax or other charge shall have been paid or it has
been established to the Corporation's satisfaction that no such tax or other
charge is due.

                  (f) Any notice to be given to the Corporation by the Warrant
Agent pursuant to this Section 2.03 shall be by


                                      -19-

telephone (promptly confirmed in writing) or telecopy (receipt to be promptly
confirmed by telephone).

                  Section 2.04. Designation of Agent for Receipt of Notice. The
Corporation may from time to time designate in writing to the Warrant Agent a
single designee for receipt of all notices required to be given by the Warrant
Agent to the Corporation pursuant to this Article II and all such notices
thereafter shall be given in the manner herein provided by the Warrant Agent to
such designee and each such notice shall be as effective as if given directly to
the Corporation.



                                   ARTICLE III

                          OTHER PROVISIONS RELATING TO
                                RIGHTS OF HOLDERS

                  Section 3.01. Treatment of Holders. (a) The Corporation, the
Warrant Agent and any agent of the Corporation or the Warrant Agent may deem and
treat the Person in whose name each Global Warrant Certificate shall be
registered in the records of the Warrant Agent as the absolute Holder of all
right, title and interest in such Global Warrant Certificate (notwithstanding
any notation of ownership or other writing thereon) for all purposes hereunder
and as the Person entitled to exercise the rights represented by the Warrants
evidenced thereby, whether or not such Warrants shall be exercised or deemed to
be exercised, and neither the Corporation nor the Warrant Agent, nor any agent
of the Corporation or the Warrant Agent shall be affected by any notice to the
contrary, except that the Warrant Agent and the Corporation shall be entitled to
rely on and act pursuant to instructions of Depository Participants as
contemplated by Article II of this Agreement.

                  (b) Prior to due presentment of a Definitive Warrant
Certificate for registration of transfer, the Corporation, the Warrant Agent and
any agent of the Corporation or the Warrant Agent may treat [if Debt Securities
and Warrants that are not immediately detachable are offered -- , prior to the
Detachable Date, the Person in whose name the Offered Debt Security to which
such Warrant Certificate was initially attached shall be

                                      -20-

registered upon the register relating to such Offered Debt Securities and, after
such Detachable Date,] the Person in whose name such Definitive Warrant
Certificate is registered as the absolute Holder of all right, title and
interest in such Definitive Warrant Certificate (notwithstanding any notation of
ownership or other writing thereon) for all purposes hereunder and as the Person
entitled to exercise the rights represented by the Warrants evidenced thereby,
whether or not such Warrants shall be exercised or deemed to be exercised, and
neither the Corporation, the Warrant Agent nor any agent of the Corporation or
the Warrant Agent shall be affected by notice to the contrary.

                  Section 3.02. Holder or Owner of Warrant May Enforce Rights.
Notwithstanding any other provision of this Agreement, any Owner, in the case of
Book-Entry Warrants, and any Holder, in the case of Certificated Warrants,
without the consent of the Warrant Agent, the Trustee, the holder of any Warrant
Debt Securities or the Owner or Holder of any other Warrant, may, in and for
such Owner's or Holder's own behalf, and for such Owner's or Holder's own
benefit, enforce, and may institute and maintain any suit, action or proceeding
against the Corporation suitable to enforce, or otherwise in respect of, such
Owner's or Holder's right to exercise, and to receive the Warrant Debt
Securities issuable upon exercise of, such Owner's or Holder's Warrants as
provided in such Warrants and in this Agreement.



                                   ARTICLE IV

                          CONCERNING THE WARRANT AGENT

                  Section 4.01. Warrant Agent. The Corporation hereby appoints
[name of Warrant Agent] as the Warrant Agent of the Corporation in respect of
the Warrants upon the terms and subject to the conditions set forth herein and
in the Warrants, and [name of Warrant Agent] hereby accepts such appointment.
The Warrant Agent shall have the powers and authority granted to and conferred
upon it herein and in the Warrants and such further powers and authority
acceptable to it to act on behalf of the Corporation as the Corporation may
hereafter grant to or


                                      -21-

confer upon it. All of the terms and provisions with respect to such powers and
authority contained in the Warrants are subject to and governed by the terms and
provisions hereof.

                  Section 4.02. Certain Duties of the Warrant Agent. (a) Except
during the continuation of a default in the performance by the Corporation of
its obligations in respect of the Warrants, the Warrant Agent undertakes to
perform such duties and only such duties as are specifically set forth in this
Agreement, and no implied covenants or obligations shall be read into this
Agreement against the Warrant Agent.

                  (b) No provision of this Agreement shall require the Warrant
Agent 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.

                  Section 4.03. Conditions of Warrant Agent's Obligations. The
Warrant Agent accepts its obligations set forth herein upon and subject to the
terms and conditions hereof and of the Warrants, including the following, to all
of which the Corporation agrees and to all of which the rights hereunder of the
Owners and Holders from time to time of the Warrants shall be subject:

                  (a) The Corporation agrees promptly to pay the Warrant Agent
         the compensation to be agreed upon with the Corporation for all
         services rendered by the Warrant Agent and to reimburse the Warrant
         Agent for its reasonable out-of-pocket expenses, disbursements and
         advances (including reasonable attorneys' fees and expenses and
         reasonable compensation, expenses and disbursements of its agents)
         incurred by the Warrant Agent without negligence, bad faith or breach
         of this Agreement on its part in connection with the services rendered
         by it hereunder. The Corporation also agrees to indemnify the Warrant
         Agent for, and to hold it harmless against, any loss, liability or
         expense (including reasonable attorneys' fees and expenses) incurred
         without negligence, bad faith or breach of

                                      -22-

         this Agreement on the part of the Warrant Agent, arising out of or in
         connection with its acting as such Warrant Agent hereunder or with
         respect to the Warrants, including the reasonable 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. The
         obligations of the Corporation under this subsection (a) shall survive
         the exercise of the Warrants and the resignation or removal of the
         Warrant Agent.

                  (b) The Warrant Agent shall be protected and shall incur no
         liability for or in respect of any action taken or omitted or thing
         suffered by it in reliance upon any Warrant, resolution, opinion,
         report, request, notice, direction, consent, certificate, affidavit,
         statement or other paper or document reasonably believed by it to be
         genuine and to have been presented or signed by the proper parties,
         provided that any request or direction of the Corporation shall be
         sufficiently evidenced by a Corporation Order delivered to the Warrant
         Agent, and any resolution of the Board of Directors shall be
         sufficiently evidenced by a copy of the resolution certified by the
         Secretary or an Assistant Secretary to have been duly adopted by the
         Board of Directors of the Corporation, or by a committee of such Board
         of Directors or an officer of the Corporation appointed by the Board of
         Directors of the Corporation for such purpose, and to be in full force
         and effect on the date of such certification and delivered to the
         Warrant Agent (any such resolution, a "Board Resolution").

                  (c) The Warrant Agent may consult with counsel satisfactory to
         it, which may include counsel to the Corporation, and the written
         opinion of such 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 accordance with such written opinion.

                  (d) The Warrant Agent shall not be bound to make any
         investigation into the facts or matters stated in any Corporation Order
         or Board Resolution, but the Warrant Agent, in its discretion, may make
         such

                                      -23-

         further inquiry or investigation into such facts or matters as it may
         see fit.

                  (e) The Warrant Agent, and any of its officers, directors and
         employees, in its individual or any other capacity, may become the
         Owner or Holder of, or acquire any interest in, any Warrants or other
         obligations of the Corporation, with the same rights that it or they
         would have if it were not the Warrant Agent hereunder, and, to the
         extent permitted by applicable law, it or they may engage or be
         interested in any financial or other transaction with the Corporation
         and may act on, or as depositary, trustee or agent for, any committee
         or body of Owners or Holders of Warrants or holders of [Offered Debt
         Securities or] Warrant Debt Securities or other obligations of the
         Corporation as freely as if it were not the Warrant Agent hereunder.
         Nothing in this Warrant Agreement shall be deemed to prevent the
         Warrant Agent from acting as Trustee under the Indenture.

                  (f) The Warrant Agent shall not be under any liability for
         interest on any monies at any time received by it pursuant to any of
         the provisions of this Agreement or of the Warrants except as otherwise
         agreed with the Corporation, nor shall it be obligated to segregate
         such monies from other monies held by it, except as required by law.

                  (g) The Warrant Agent shall not be under any liability with
         respect to the validity or sufficiency of this Agreement or the
         execution and delivery hereof (except the due execution and delivery
         hereof by the Warrant Agent) or with respect to the validity or
         execution of the Warrants or the Warrant Certificates (except the
         countersignature thereof).

                  (h) The recitals contained herein and in the Warrants (except
         as to the Warrant Agent's countersignature thereon) shall be taken as
         the statements of the Corporation, and the Warrant Agent assumes no
         responsibility for the correctness thereof.

                  (i) The Warrant Agent shall not be accountable or under any
         duty or responsibility for the use by the


                                      -24-

         Corporation of any of the Warrant Certificates countersigned by the
         Warrant Agent and delivered by it to the Corporation pursuant to this
         Agreement or for the application by the Corporation of any proceeds.

                  (j) The Warrant Agent shall have no duty or responsibility in
         case of any default by the Corporation in the performance of its
         covenants or agreements contained herein or in the Warrants or in the
         [Offered Debt Securities or] Warrant Debt Securities or in the case of
         the receipt of any written demand from an Owner or Holder of a Warrant
         with respect to such default, including, without limitation, any duty
         or responsibility to initiate or attempt to initiate any proceedings at
         law or otherwise or, except as provided in Section 8.03, to make any
         demand upon the Corporation.

                  (k) In acting under this Agreement and in connection with the
         Warrants, the Warrant Agent is acting solely as the agent of the
         Corporation and does not assume any obligation or relationship of
         agency or trust for or with any of the Owners or Holders of the
         Warrants.

                  Section 4.04. Compliance With Applicable Laws. The Warrant
Agent agrees to comply with all applicable federal and state laws imposing
obligations on it in respect of the services rendered by it under this Agreement
and in connection with the Warrants, including (but not limited to) the
provisions of United States federal income tax laws regarding information
reporting and backup withholding. The Warrant Agent expressly assumes all
liability for its failure to comply with any such laws imposing obligations on
it, including (but not limited to) any liability for its failure to comply with
any applicable provisions of United States federal income tax laws regarding
information reporting and backup withholding.

                  Section 4.05. Corporate Warrant Agent Required; Eligibility.
The Corporation agrees, for the benefit of the Owners or Holders from time to
time of the Warrants, that there shall at all times be a Warrant Agent hereunder
until all of the Warrants have been exercised or are no longer exercisable,
which shall be a banking institution organized under the laws of the United
States of America or

                                      -25-

one of the states thereof and having an office or an agent's office [south of
Chambers Street in the Borough of Manhattan, The City of New York].

                  Section 4.06. Resignation and Removal; Appointment of
Successor. (a) No resignation or removal of the Warrant Agent and no appointment
of a successor Warrant Agent pursuant to this Section 4.06 shall become
effective until the acceptance of appointment by the successor Warrant Agent
under Section 4.07.

                  (b) The Warrant Agent may resign at any time by giving written
notice of such resignation to the Corporation specifying such resignation and
the date on which it desires such resignation to become effective, provided
that, without the consent of the Corporation, such date shall not be less than
90 days after the date on which such notice is given. If an instrument of
acceptance by a successor Warrant Agent shall not have been delivered to the
Warrant Agent within 90 days after the giving of such notice of resignation, the
resigning Warrant Agent may petition any court of competent jurisdiction for the
appointment of a successor Warrant Agent with respect to the Warrants.

                  (c) The Corporation may remove the Warrant Agent at any time
by giving written notice thereof to the Warrant Agent specifying such removal
and the date on which the Corporation desires such removal to become effective.

                  (d)      If at any time:

                  (i) the Warrant Agent shall cease to be eligible to act as
         such under Section 4.05 and shall fail to resign after the Corporation
         shall have delivered a written request therefor, or

                  (ii) the Warrant Agent shall become incapable of acting as
         such, or shall be adjudged a bankrupt or insolvent, or shall file a
         voluntary petition in bankruptcy or make an assignment for the benefit
         of its creditors or consent to the appointment of a receiver or
         custodian of all or any


                                      -26-

         substantial part of its property, or shall admit in writing its
         inability to pay or meet its debts as they mature, or a receiver or
         custodian of it or of all or any substantial part of its property shall
         be appointed, or an order of any court shall be entered approving any
         petition filed by or against it under the provisions of any applicable
         bankruptcy or similar law, or any public officer shall take charge or
         control of the Warrant Agent or of its property or affairs, for the
         purpose of rehabilitation, conservation or liquidation, or

                  (iii) the Corporation shall elect to remove the Warrant Agent,
         provided that no default shall then exist with respect to the Warrants,

then in any such case, the Corporation by a Board Resolution may remove the
Warrant Agent with respect to all the Warrants.

                  (e) If the Warrant Agent shall resign or be removed, or if a
vacancy shall occur in the office of the Warrant Agent for any other reason, the
Corporation, by a Board Resolution, shall promptly appoint a successor Warrant
Agent with respect to the Warrants, it being understood that at any time there
shall be only one Warrant Agent with respect to the Warrants.

                  (f) The Corporation shall give notice to the Owners or Holders
of the Warrants of each resignation and each removal of the Warrant Agent and
each appointment of a successor Warrant Agent with respect to the Warrants in
accordance with Section 8.05. Each such notice shall include the name of the
successor Warrant Agent and the address of its Warrant Agent Office.

                  Section 4.07. Acceptance of Appointment by Successor. (a) If a
successor Warrant Agent is appointed hereunder, such successor Warrant Agent so
appointed shall execute, acknowledge and deliver to the Corporation and to the
retiring Warrant Agent an instrument accepting such appointment, and thereupon
the resignation or removal of the retiring Warrant Agent shall become effective
and such successor Warrant Agent, without any further act, deed or conveyance,
shall become vested with all the rights, powers and duties of the retiring
Warrant Agent; provided, however, that on the request of the Corporation or the
successor Warrant Agent, such retiring Warrant Agent shall, upon payment of its
charges and disbursements then unpaid,


                                      -27-

execute and deliver an instrument transferring to such successor Warrant Agent
all the rights and powers of the retiring Warrant Agent and shall duly assign,
transfer and deliver to such successor Warrant Agent all property and money held
by such retiring Warrant Agent hereunder.

                  (b) Upon the request of any such successor Warrant Agent, the
Corporation shall execute any and all instruments for more fully and certainly
vesting in and confirming to such successor Warrant Agent all such rights and
powers referred to in Section 4.07(a).

                  (c) No successor Warrant Agent shall accept its appointment,
and no such acceptance shall be effective, unless at the time of such acceptance
such successor Warrant Agent shall be qualified and eligible under this Article
IV.

                  Section 4.08. Merger, Conversion, Consolidation or Succession
to Business. Any corporation into which the Warrant 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 the Warrant Agent shall be
a party, or any corporation succeeding to all or substantially all of the
business of the Warrant Agent, shall be the successor of the Warrant Agent
hereunder, without the execution or filing of any paper or any further act on
the part of any of the parties hereto, provided that such corporation shall be
otherwise qualified and eligible under this Article IV. If any Warrant
Certificates shall have been countersigned, but not delivered, by the Warrant
Agent then in office, any successor by merger, conversion or consolidation to
such countersigning Warrant Agent may adopt such countersignature and deliver
the Warrant Certificates so countersigned with the same effect as if such
successor Warrant Agent had itself countersigned such Warrant Certificates.



                                    ARTICLE V

                CONSOLIDATION, MERGER, SALE, LEASE OR CONVEYANCE

                  Section 5.01. Consolidations and Mergers of the Corporation
and Sales, Leases and Conveyances Permitted

                                      -28-

Subject to Certain Conditions. (a) The Corporation may consolidate with, or
sell, lease or convey all or substantially all of its assets to, or merge with
or into any other corporation, provided that, in any such case, (i) either the
Corporation shall be the continuing corporation, or the successor corporation
shall be a corporation organized and existing under the laws of the United
States of America or a state thereof and such successor corporation shall
expressly assume, by Supplemental Agreement (as defined in Section 6.01(a))
satisfactory to the Warrant Agent and executed and delivered to the Warrant
Agent by such corporation, the due and punctual observance of the obligations of
the Corporation hereunder and under all unexercised Warrants, according to their
tenor, and (ii) the Corporation or such successor corporation, as the case may
be, shall not, immediately after such merger or consolidation, or such sale,
lease or conveyance, be in default in the performance of any such covenant or
condition. In case of any such consolidation, merger, sale, lease or conveyance
and upon such assumption by the successor corporation, such successor
corporation shall succeed to and be substituted for the Corporation, with the
same effect as if it had been named herein as such, and the predecessor
Corporation, except in the event of a lease, shall be relieved of any further
obligation hereunder or under the Warrants. Such successor corporation thereupon
may cause to be signed, and may issue either in its own name or in the name of
the Corporation, new Global Warrant Certificates or Definitive Warrant
Certificates, as the case may be, representing Warrants not theretofore
exercised, in exchange and substitution for the Global Warrant Certificates and
Definitive Warrant Certificates theretofore issued, and any or all of the
Warrant Debt Securities issuable pursuant to the terms of any such unexercised
Warrants; and upon the order of such successor corporation, instead of the
Corporation, and subject to all the terms, conditions and limitations in this
Agreement prescribed, the Warrant Agent shall countersign and shall deliver the
new Global Warrant Certificates or Definitive Warrant Certificates, as the case
may be, that such successor corporation shall have caused to be signed and
delivered to the Warrant Agent for countersignature. Such Global Warrant
Certificates or Definitive Warrant Certificates, as the case may be, shall in
all respects have the same legal rank and benefit under


                                      -29-

this Agreement as the Warrant Certificates theretofore issued in accordance with
the terms of this Agreement as though such new Warrant Certificates had been
issued at the date of issue of the Warrant Certificates for which they are
exchanged, and all the Warrant Debt Securities so issued shall in all respects
have the same legal rank and benefit under the Indenture as the Warrant Debt
Securities theretofore or thereafter issued in accordance with its terms of this
Agreement and the Indenture. In case of any such consolidation, merger, sale,
lease or conveyance, such changes in phraseology and form (but not in substance)
may be made in the new Warrant Certificates and Warrant Debt Securities
thereafter to be issued as may be appropriate.

                  (b) The Warrant Agent may receive a written opinion of counsel
(who may be an employee of the Corporation or other counsel acceptable to the
Warrant Agent) (an "Opinion of Counsel") as conclusive evidence that any such
consolidation, merger, sale, lease or conveyance, and any such assumption,
complies with the provisions of this Article V.



                                   ARTICLE VI

                             SUPPLEMENTAL AGREEMENTS

                  Section 6.01. Amendment of Debt Warrant Agreement. (a) This
Agreement and the Warrants may be amended by the Corporation, when authorized by
a Board Resolution, and the Warrant Agent (which amendment shall take the form
of a supplemental index warrant agreement) (each, a "Supplemental Agreement")),
without the consent of the Owners or Holders of the Warrants, for the purpose
of:

                       (i) curing any ambiguity or of curing, correcting or
         supplementing any defective or inconsistent provision contained herein
         or therein, or of making any other provisions with respect to matters
         or questions arising under this Agreement that shall not be
         inconsistent with the provisions of this Agreement or the Warrants; or

                       (ii) evidencing the succession of another corporation to
         the Corporation and the assumption by any such successor of the
         covenants of the Corporation

                                      -30-

         contained herein and in the Warrants in accordance with Article V; or

                       (iii) appointing a successor Depository in accordance
         with Section 1.01(e); or

                       (iv) evidencing and providing for the acceptance of
         appointment hereunder by a successor Warrant Agent in accordance with
         Section 4.07; or

                       (v) adding to the covenants of the Corporation for the
         benefit of the Owners or Holders of the Warrants or surrendering any
         right or power herein conferred upon the Corporation; or

                       (vi) issuing Warrants in the form of Definitive Warrant
         Certificates in accordance with Section 1.01(c); or

                       (vii) amending this Agreement and the Warrants in any
         manner that the Corporation may deem to be necessary or desirable and
         that will not materially and adversely affect the interests of the
         Owners or Holders of the Warrants.

                  (b) The Corporation and the Warrant Agent may amend this
Agreement and the Warrants (which amendment shall take the form of a
Supplemental Agreement), with the consent of the Owners or Holders, as the case
may be, of not fewer than 66-2/3% in number of the unexercised Warrants affected
by such amendment, for the purpose of adding any provisions to or changing in
any manner or eliminating any of the provisions of this Agreement or of
modifying in any manner the rights of the Owners or Holders of the Warrants
under this Agreement; provided, however, that, without the consent of each Owner
or Holder affected thereby, no such amendment may be made that changes the
determination of the Cash Settlement Value [or Cancellation Amount, as the case
may be,] of the Warrants (or any aspects of such determination) so as to reduce
the amount receivable upon exercise or deemed exercise of the Warrants, shortens
the period of time during which the Warrants may be exercised, or otherwise
materially and adversely affects the exercise rights of the Owners or Holders,
as the case may be, or reduces the number of unexercised Warrants the consent of
the Owners or Holders

                                      -31-

of which is required for amendment of this Agreement or the Warrants. The
Corporation and the Warrant Agent shall be entitled to rely upon certification
in form satisfactory to each of them that any requisite consent has been
obtained from the Owners of Warrants represented by a Global Warrant
Certificate. Such certification may be provided by Depository Participants
acting on behalf of such Owners of Warrants, provided that any such
certification is accompanied by a certification from the Depository as to the
Global Warrant Certificate holdings of such Depository Participants.

                  Section 6.02. Form of Approval of Supplemental Agreements by
Owners or Holders. It shall not be necessary for the Owners or Holders of the
Warrants to approve the particular form of any proposed Supplemental Agreement,
but it shall be sufficient if the Owners or Holders, as the case may be, shall
approve the substance of the Supplemental Agreement.

                  Section 6.03. Effect of Supplemental Agreements. Upon the
execution of any Supplemental Agreement under this Article, this Agreement shall
be modified in accordance therewith, such Supplemental Agreement shall form a
part of this Agreement for all purposes, and, subject to the proviso to the
first sentence of Section 6.01(b), every Owner or Holder of Warrants theretofore
or thereafter countersigned and delivered hereunder shall be bound thereby.

                  Section 6.04. Reference in Warrants to Supplemental
Agreements. Warrants countersigned and delivered after the execution of any
Supplemental Agreement pursuant to this Article may, and shall if required by
the Warrant Agent, bear a notation in form approved by the Warrant Agent as to
any matter provided for in such Supplemental Agreement. If the Corporation shall
so determine, new Warrants so modified as to conform, in the opinion of the
Warrant Agent and the Corporation, to any such Supplemental Agreement may be
prepared and executed by the Corporation and countersigned and delivered by the
Warrant Agent in exchange for unexercised Warrants.


                                      -32-

                                   ARTICLE VII

                          COVENANTS OF THE CORPORATION

                  Section 7.01. Delivery of Prospectus. The Corporation shall
furnish to the Warrant Agent sufficient copies of a prospectus, appropriately
supplemented, relating to the Warrant Debt Securities (the "Prospectus"), and
the Warrant Agent agrees that, upon the exercise of any Warrant Certificate, the
Warrant Agent shall deliver to the person designated to receive Warrant Debt
Securities, prior to or concurrently with the delivery of such Warrant Debt
Securities, a copy of such Prospectus, as so supplemented.

                  Section 7.02. Governmental Approvals. The Corporation shall
from time to time take all reasonable action necessary to obtain and keep
effective any and all permits, consents and approvals of governmental agencies
and authorities [and the [name of national securities exchange]] and shall make
all filings under United States federal and state laws (including, without
limitation, the maintenance of the effectiveness of a registration statement in
respect of the Warrant Debt Securities under the Securities Act of 1933), that
may be or become requisite in connection with the issuance, sale, trading,
transfer, delivery or exercise of the Warrants, each Global Warrant Certificate
and each Definitive Warrant Certificate or the issuance, sale, transfer and
delivery of the Warrant Debt Securities issued upon exercise of the Warrants or
upon the expiration of the period during which the Warrants are exercisable.

                  Section 7.03. Delivery of Warrant Debt Securities. The
Corporation agrees, for the benefit of the Owners or Holders of the Warrants,
that it will duly and punctually deliver the Warrant Debt Securities issuable
upon exercise of each Warrant in accordance with the terms of the Warrants and
this Agreement, and that the right of each such Owner or Holder, as the case may
be, to receive delivery of the Warrant Debt Securities issuable upon the
exercise of each such Warrant when such delivery is due shall be absolute and
unconditional.

                  Section 7.04. Maintenance of Office or Agency; Unclaimed
Moneys. (a) The Corporation shall maintain an office and agency at which the
Warrants may be presented or

                                      -33-

surrendered for exercise or registration of transfer or exchange or cancellation
and where notices and demands to or upon the Corporation in respect of the
Warrants and this Agreement may be served, which office and agency shall be the
same as the location of the Warrant Agent Office, and the Corporation hereby
appoints the Warrant Agent as its agent to receive all such presentations,
surrenders, notices and demands.

                  (b) The Corporation shall, on or prior to the date on which
delivery of the Warrant Debt Securities issuable upon exercise of any Warrants
is due, cause the Trustee to issue such Warrant Debt Securities, which Warrant
Debt Securities shall be held for the benefit of the Persons entitled to receive
such Warrant Debt Securities.

                  (c) Any money deposited with the Warrant Agent for the payment
of any amounts that may become due and payable with respect to any Warrant, and
any Warrant Debt Securities deposited with the Warrant Agent for delivery upon
exercise of any Warrant, and remaining unclaimed for three years after such
payment or delivery has become due, shall be paid or returned to the
Corporation, at the request of the Corporation, and the Person entitled to such
money or Warrant Debt Securities shall thereafter, as an unsecured general
creditor, look only to the Corporation for payment or delivery thereof, and all
liability of the Warrant Agent with respect to such money or Warrant Debt
Securities shall thereupon cease; provided, however, that the Warrant Agent,
before being required to make any such repayment or return, may at the expense
of the Corporation, cause notice to be given in accordance with Section 8.05 to
the Person entitled to such money or Warrant Debt Securities that such money or
Warrant Debt Securities remain unclaimed and that, after a date specified
therein, which shall be not less than 30 days from the date of such notice, any
unclaimed balance of such money or unclaimed Warrant Debt Securities then
remaining will be repaid or returned to the Corporation.

                  Section 7.05. Corporate Existence. Subject to Article V, the
Corporation shall do or cause to be done all things necessary to preserve and
keep in full force and effect its corporate existence, rights (charter and
statutory) and franchises; provided, however, that the


                                      -34-

Corporation shall not be required to preserve any right or franchise if its
Board of Directors or a committee thereof shall determine that the preservation
thereof is no longer desirable in the conduct of the business of the Corporation
and that the loss thereof is not disadvantageous in any material respect to the
Owners or Holders of the Warrants, as the case may be.



                                  ARTICLE VIII

                                  MISCELLANEOUS

                  Section 8.01. Reopening of Issue of Warrants. The Corporation
may, from time to time, issue additional Warrants under this Agreement. All
Warrants issued hereunder, from and after the date they are issued, shall be
identical.

                  Section 8.02. Payment of Taxes. The Corporation shall pay all
documentary stamp taxes attributable to the initial issuance of Warrants;
provided, however, that the Corporation shall not be required to pay any tax or
other governmental charge that may be payable in respect of any transfer
involving any beneficial or record interest in or ownership interest of any
Warrants.

                  Section 8.03. Notices and Demands to the Corporation and
Warrant Agent. If the Warrant Agent shall receive any notice or demand addressed
to the Corporation by any Owner or Holder pursuant to the provisions of the
Warrants, the Warrant Agent shall promptly forward such notice or demand to the
Corporation.

                  Section 8.04. Addresses for Notices. Any communications from
the Corporation to the Warrant Agent with respect to this Agreement shall be
addressed to [name of Warrant Agent], [address] (facsimile: (___) ___-____)
(telephone: (___) ___-____), Attention: [Corporate Trust Department]; and any
communications from the Warrant Agent to the Corporation with respect to this
Agreement shall be addressed to UBS AG, 299 Park Avenue, New York, New York
10017 (facsimile: (212) ___-____) (telephone: (212) ___-____), Attention:
[Robert Dinerstein] (or, in either case, at such other address as shall be
specified in

                                      -35-

writing to the other by the Warrant Agent or the Corporation, as the case may
be).

                  Section 8.05. Notices to Owners and Holders. The Corporation
or the Warrant Agent shall give any notice to be given to the Owners of
Book-Entry Warrants by providing the Depository with a form of notice to be
distributed by the Depository to Depository Participants in accordance with the
customs and practices of the Depository. The Corporation or the Warrant Agent
shall give notice to the Holders of Certificated Warrants by mailing written
notice by first class mail, postage prepaid, to such Holders as their names and
addresses appear in the Warrant Register [or, prior to the Detachable Date, on
the register of the Offered Debt Securities].

                  Section 8.05. GOVERNING LAW. THIS AGREEMENT AND EACH WARRANT
ISSUED HEREUNDER SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS
OF THE STATE OF NEW YORK.

                  Section 8.06. Benefits of Debt Warrant Agreement. Nothing in
this Agreement or in the Warrants expressed or implied and nothing that may be
inferred from any of the provisions hereof or thereof is intended, or shall be
construed, to confer upon, or give to, any Person other than the Corporation,
the Warrant Agent and their respective successors and assigns, and the Owners or
Holders of the Warrants, as the case may be, any right, remedy or claim under or
by reason of this Agreement or the Warrants or of any covenant, condition,
stipulation, promise or agreement hereof or thereof, and all covenants,
conditions, stipulations, promises and agreements contained in this Agreement or
in the Warrants shall be for the sole and exclusive benefit of the Corporation
and the Warrant Agent and their respective successors and assigns and of the
Owners or Holders of the Warrants, as the case may be.

                  Section 8.07. Successors and Assigns. All covenants and
agreements in this Agreement by the Corporation shall bind its successors and
assigns, whether so expressed or not.

                  Section 8.08. Debt Warrant Agreement and Warrants Solely
Corporate Obligations. No recourse for the payment of any amounts due in respect
of, or for the


                                      -36-

delivery of any Warrant Debt Securities issuable upon exercise of, any Warrant
or for any claim based on any Warrant or this Agreement shall be had against any
director or officer or stockholder, past, present or future, of the Corporation.
Any such claim against any such Person is expressly waived as a condition of,
and as consideration for, the execution and delivery of this Agreement and the
issue of the Warrants.

                  Section 8.09. Severability. If any provision in this Agreement
or in the Warrants shall be invalid, illegal, or unenforceable in any
jurisdiction, the validity, legality and enforceability of the remaining
provisions, or of such provisions in any other jurisdiction, shall not in any
way be affected or impaired thereby.

                  Section 8.10. Headings. The descriptive headings of the
several Articles and Sections and the Table of Contents of this Agreement are
for convenience only and shall not control or affect the meaning or construction
of any of the provisions hereof.

                  Section 8.11. Counterparts. This Agreement may be executed by
the parties hereto in any number of counterparts, each of which when so executed
and delivered shall be deemed to be an original, but all such counterparts shall
together constitute but one and the same instrument.

                  Section 8.12. Inspection of Debt Warrant Agreement. A copy of
this Agreement shall be available at all reasonable times at the Warrant Agent
Office for inspection by the Owners or Holders of the Warrants, as the case may
be, the Depository Participants and the Indirect Participants. In the case of
Certificated Warrants, the Warrant Agent may require the Holder of such Warrant
to submit such Holder's Warrant Certificate for inspection by the Warrant Agent.


                                      -37-

                  IN WITNESS WHEREOF, this Debt Warrant Agreement has been duly
executed by the parties hereto as of the day and year first above written.

                                                   UBS AG


                                                   By:__________________________
                                                      Name:
                                                      Title:



                                                   By:__________________________
                                                      Name:
                                                      Title:







                                                   [NAME OF WARRANT AGENT],
                                                   as Warrant Agent


                                                   By:__________________________
                                                      Name:
                                                      Title:

[SEAL]

Attest:



____________________________
[Assistant] Secretary


                                      -38-

                                                                       EXHIBIT A


[Form of Legend if Debt Securities with Warrants that are not immediately
detachable are offered: PRIOR TO  ____________, THIS WARRANT CERTIFICATE MAY BE
TRANSFERRED OR EXCHANGED IF AND ONLY IF THE [TITLE OF OFFERED DEBT SECURITY] TO
WHICH IT WAS INITIALLY ATTACHED IS SO TRANSFERRED OR EXCHANGED.]

                       [Form of Legend if Warrants are not
                        immediately exercisable: WARRANTS
                      EVIDENCED BY THIS WARRANT CERTIFICATE
                      CANNOT BE EXERCISED PRIOR TO ________
                                   __, 200__.]

                    EXERCISABLE ONLY IF COUNTERSIGNED BY THE
                        WARRANT AGENT AS PROVIDED HEREIN

                   VOID AFTER [3:00 P.M.], NEW YORK CITY TIME,
                              ON ________ __, 200__

No. _________                                          CUSIP No. ____________

                           GLOBAL WARRANT CERTIFICATE
                                  representing
                              Warrants to purchase
                       [Title of Warrant Debt Securities]

                                     UBS AG

                  This certifies that [______________] or registered assigns is
the registered holder of [insert number initially issued] Warrants to purchase
certain debt securities (the "Warrants"), or such lesser amount as is indicated
in the records of [name of Warrant Agent], as Warrant Agent. Each Warrant
entitles the [beneficial owner thereof (an "Owner")] [Holder (as defined below)
hereof], subject to the provisions contained herein and in the Debt Warrant
Agreement referred to below, to purchase from UBS AG, a New York corporation
(the "Corporation"), $_________ principal amount of the Corporation's [Title of
Warrant Debt Securities] (the "Warrant Debt Securities") of UBS AG (the
"Corporation"), issued or to be issued under the Indenture (as hereinafter
defined), at the Exercise Price set forth below. [During the period from
________ __, 200__ through and including ________ __, 200__,] the exercise price
of each Warrant shall be [$_______] [____% of the principal amount of the
Warrant Debt Securities

                                      A-1

subject to such Warrant] plus [accrued amortization, if any, of the original
issue discount of the Warrant Debt Securities] [accrued interest, if any, from
the most recent date from which interest shall have been paid on the Warrant
Debt Securities or, if no interest shall have been paid on the Warrant Debt
Securities, from ________ __, 200__]. [During the period from ________ __, 200__
through and including ________ __, 200__, the exercise price of each Warrant
shall be [$_______] [____% of the principal amount of the Warrant Debt
Securities subject to such Warrant] plus [accrued amortization, if any, of the
original issue discount of the Warrant Debt Securities] [accrued interest, if
any, from the most recent date from which interest shall have been paid on the
Warrant Debt Securities or, if no interest shall have been paid on the Warrant
Debt Securities, from ________ __, 200__].] [In each case, the original issue
discount of $_______ for each $1,000 principal amount of Warrant Debt Securities
shall be amortized at a ___% annual rate, computed on a[n] [semi-]annual basis
[using a 360-day year consisting of twelve 30-day months].] The exercise price
of each Warrant as set forth above is referred to in this Warrant Certificate as
the "Exercise Price."

                  The term "Holder" as used herein shall mean [if Debt
Securities with Warrants that are not immediately detachable are offered -- ,
prior to ________________, 19__ (the "Detachable Date"), the registered owner of
the Corporation's [title of Offered Debt Securities] to which such Warrant
Certificate was initially attached, and after such Detachable Date,] the person
in whose name at the time such Warrant Certificate shall be registered upon the
books to be maintained by the Warrant Agent for that purpose pursuant to Section
1.04 of the Debt Warrant Agreement.

                  Subject to the terms of the Debt Warrant Agreement, each
Warrant may be exercised in whole but not in part on any New York Business Day
(as defined below) from [the date of issuance (specify other date if
applicable)] until [3:00 P.M.], New York City time, on [_________ (specify date
upon which right to exercise Warrants expires)] or, if such date is not a New
York Business Day, on the next succeeding New York Business Day (the "Expiration
Date"). Each Warrant not exercised at or before [3:00 P.M.], New York City time,
on the Expiration Date shall become void, and all rights of the Owner or

                                      A-2

Holder of such Warrant under this Agreement or otherwise shall cease. Not fewer
than [(specify minimum exercise amount)] [nor more than [(specify maximum
exercise amount)] Warrants may be exercised by or on behalf of any one [Owner]
[Holder] at any one time. References herein to "U.S. dollars", "U.S.$" or "$"
are references to the currency of the United States of America. As used herein,
the term "New York Business Day" means any day other than a Saturday or Sunday
or a day on which the New York Stock Exchange or the American Stock Exchange [or
(list any other relevant securities exchanges)] is not open for securities
trading or banking institutions generally in The City of New York are authorized
or required by law or executive order to close.

                  This [Global] [Definitive] Warrant Certificate is issued under
and in accordance with the Debt Warrant Agreement, dated as of ________ __,
200__ (the "Debt Warrant Agreement"), between the Corporation and the Warrant
Agent, and is subject to the terms and provisions contained in the Debt Warrant
Agreement, to all of which terms and provisions all [Owners] [Holders] of the
Warrants represented by this [Global] [Definitive] Warrant Certificate [and the
Holder of this Global Warrant Certificate] consent by acceptance hereof [by the
Depository (as defined below)]. Copies of the Debt Warrant Agreement are on file
at the Warrant Agent Office at ______________, New York, New York, _____,
Attention: Corporate Trust Department, or at such other office as may be
specified in a notice given to the [Owners] [Holders] of the Warrants. [Except
as provided in the Debt Warrant Agreement, Owners will not be entitled to
receive definitive certificates evidencing their Warrants. Warrant holdings will
be held through a depository selected by the Corporation, which initially is
[The Depository Trust Company], or its agent (the "Depository", which term, as
used herein, includes any successor depository selected by the Corporation) as
further provided in the Debt Warrant Agreement.]

                  Capitalized terms included herein but not defined herein have
the meanings assigned to them in the Debt Warrant Agreement.

                  The Warrants evidenced by this Warrant Certificate may be
exercised at any time during the period

                                      A-3

specified above by delivering (i) [such Warrant on the records of the Depository
free to the Warrant Account] [this Warrant Certificate to the Warrant Agent at
the Warrant Agent Office], (ii) an Exercise Notice for such Warrant in good
order in the form of [Exhibit B-1] [Exhibit B-2] to the Debt Warrant Agreement,
and (iii) payment of the Exercise Price in U.S. dollars [in cash or by cashier's
check or official bank check in New York Clearing House funds] [by bank wire
transfer in immediately available funds] payable to the account of the
Corporation.

                  By [5:00 P.M.], New York City time, on the New York Business
Day on which such Exercise Notice is received (or deemed to have been received),
the Warrant Agent shall notify the Corporation (and such other parties (not to
exceed two) as the Corporation shall designate in writing) of the number of
Warrants in respect of which Exercise Notices, not rejected pursuant to the Debt
Warrant Agreement, were received (or deemed to have been received) at or prior
to [3:00 P.M.], New York City time, on such date, the number of such Exercise
Notices that were rejected by the Warrant Agent pursuant to the Debt Warrant
Agreement and the number of Warrants to which such rejected Exercise Notices
relate. By [5:00 P.M.], New York City Time, on the New York Business Day
following the Exercise Date for such Warrants the Warrant Agent shall send
notice of confirmation of exercise in substantially the form of Exhibit D to the
Debt Warrant Agreement to the appropriate [Depository Participant] [Holder].

                  At or before [3:00 P.M.], New York City time, on the [fifth]
New York Business Day following the Exercise Date for such Warrants, the
Corporation shall issue, and shall cause the Trustee to authenticate and
deliver, pursuant to the Indenture, in authorized denominations, to or upon the
order of the Holder of such Warrants, the Warrant Debt Security or Warrant Debt
Securities to which such Holder is entitled, in fully registered form,
registered in such name or names as may be directed by such Holder in the
Exercise Notice relating to such Exercised Warrant.

                  [The Warrant Agent will cause its records to be marked to
reflect the reduction in the number of Warrants represented by this Global
Warrant Certificate by the number of Warrants for which payment has been made in


                                      A-4

accordance with the Index Warrant Agreement.] [If this Definitive Warrant
Certificate shall be surrendered to the Warrant Agent for exercise of fewer than
all the Warrants represented hereby, the Warrant Agent shall issue and deliver
to the Holder of the Warrants represented hereby by first class mail at the
expense of the Corporation a Definitive Warrant Certificate representing all
Warrants remaining unexercised after such exercise.]

                  The Corporation, the Warrant Agent and any agent of the
Corporation or the Warrant Agent may deem and treat the registered Holder hereof
as the absolute Holder of all right, title and interest in the Warrants
evidenced hereby (notwithstanding any notation of ownership or other writing
hereon) for any purpose and as the Person entitled to exercise the rights
represented by the Warrants evidenced hereby, and neither the Corporation nor
the Warrant Agent nor any agent of the Corporation or the Warrant Agent shall be
affected by any notice to the contrary, except that the Corporation and the
Warrant Agent shall be entitled to rely on and act pursuant to instructions of
Depository Participants as contemplated herein and in the Index Warrant
Agreement.

                  The Warrant Debt Securities to be issued and delivered upon
the exercise of Warrants evidenced by this Warrant Certificate will be issued
under and in accordance with an Indenture, [dated as of_____, 200_ between the
Corporation and the [Trustee], and will be subject to the terms and provisions
contained in the Warrant Debt Securities and in the Indenture. Copies of the
Indenture, including the form of the Warrant Debt Securities, are on file at the
corporate trust office of the Trustee [and at __________].

                  [If Debt Securities with Warrants that are not immediately
detachable are offered -- Prior to the Detachable Date, this Warrant Certificate
may be exchanged or transferred only together with the [title of Offered Debt
Security] (the "Offered Debt Security") to which this Warrant Certificate was
initially attached, and only for the purpose of effecting, or in conjunction
with, an exchange or transfer of such Offered Debt Security. Additionally, on or
prior to the Detachable Date, each transfer of such Offered Debt Security on the
register of the Offered Debt Securities shall operate also to transfer

                                      A-5

this Warrant Certificate. After the Detachable Date, and subject to the terms of
the Debt Warrant Agreement,] [If Debt Securities with Warrants that are
immediately detachable or if Warrants alone are offered -- Subject to the terms
of the Debt Warrant Agreement,] upon due presentment for registration of
transfer or exchange of this [Global] [Definitive] Warrant Certificate at the
Warrant Agent Office, the Corporation shall execute and the Warrant Agent shall
countersign and deliver in the name of the designated transferee a new [Global]
[Definitive] Warrant Certificate or [Global] [Definitive] Warrant Certificates
of like tenor and representing in the aggregate a like number of unexercised
Warrants as evidenced by this [Global] [Definitive] Warrant Certificate at the
time of such registration of transfer, which shall be issued to the designated
transferee in exchange for this [Global] [Definitive] Warrant Certificate,
subject to the limitations provided in the Debt Warrant Agreement, without
charge.

                  The Warrants shall not entitle the Owner or Holder thereof to
any of the rights of a registered owner of the Warrant Debt Securities,
including, without limitation, the right to receive the payment of principal of,
premium, if any, or interest, if any, on the Warrant Debt Securities or to
enforce any of the covenants in the Warrant Debt Securities or the Indenture[,
except to the extent that the consent of the Owners or Holders of Warrant
Certificates is expressly required by the terms of the Warrant Debt Securities
for certain modifications of the Warrant Debt Securities]. [No amendment or
modification of the Indenture or the forms of the Warrant Debt Securities that
would adversely affect the rights of the Owners or Holders of Warrants shall be
made prior to the issuance of any Warrant Debt Securities without the written
consent of the Owners or Holders of Warrants representing the right to purchase
at least a majority of the maximum principal amount of the Warrant Debt
Securities that may be issued pursuant to Warrants that may be issued pursuant
to this Agreement.]

                  This [Global] [Definitive] Warrant Certificate and the Debt
Warrant Agreement are subject to amendment as provided in the Debt Warrant
Agreement.

                                      A-6

                  THIS [GLOBAL] [DEFINITIVE] WARRANT CERTIFICATE SHALL BE
GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

                  This [Global] [Definitive] Warrant Certificate shall not be
valid or obligatory for any purpose until countersigned by the Warrant Agent.



                                      A-7

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

Dated as of ________ __, 200__

                                                   UBS AG


                                                   By:__________________________
                                                   Name:
                                                   Title:



                                                   By:__________________________
                                                   Name:
                                                   Title:




Countersigned on the date
above written:

[NAME OF WARRANT AGENT],
as Warrant Agent

By:___________________________
   Name:
   Title:

                                      A-8

                                                                     EXHIBIT B-1


                             Form of Exercise Notice
            for Warrants Represented by a Global Warrant Certificate

[NAME OF WARRANT AGENT],
as Warrant Agent
[address]
Facsimile:  ________________
Telephone:  ________________

Attention:

      Re:   Exercise of UBS AG Debt Warrants Expiring ________ __, 200__ (the
"Warrants")

            1.    We refer to the Debt Warrant Agreement, dated as of ________
__, 200__ (the "Debt Warrant Agreement"), between UBS AG (the "Corporation") and
[Name of Warrant Agent], as Warrant Agent (the "Warrant Agent"). On behalf of
certain beneficial owners, each of whom is exercising no fewer than [__________]
Warrants covered by this Notice and whose Warrants are held through the
Depository in our name, we hereby irrevocably exercise [_____________] Warrants
(the "Exercised Warrants").

            2.    We have instructed the Depository to deliver the Exercised
Warrants free through the Depository to the Warrant Account [Account No.
_______________])[, and we have made payment of the Exercise Price as provided
in Section 2.01(b) of the Debt Warrant Agreement].

            3.    We hereby certify that we are a participant of [The Depository
Trust Company] (the "Depository") with the present right to use and receive its
services.

            4.    We hereby acknowledge that if you determine that this Exercise
Notice has not been duly completed, or is not in proper form, or you are unable
to verify that we are a participant of the Depository as provided above, this
Exercise Notice will be void and of no effect and will be deemed not to have
been delivered.

            5.    We hereby direct you to make payment to us of amounts payable
to the beneficial owners of the Tendered Warrants as a result of the exercise of
the Tendered Warrants hereunder as follows:

                  [ ]               By cashier's check or an official bank
                                    check;
or

                  [ ]               By wire transfer to the following U.S.
                                    dollar bank account in the United
                                    States:

                                    (Minimum payments of $100,000 only)

                                    Bank:________________________________

                                    Account No.:_________________________

                                    ABA Routing No.:_____________________

                                    Reference:___________________________

            Capitalized terms used herein and not defined have the meanings
assigned to them in the Debt Warrant Agreement.

Dated: ________ __, 200__

                                                     [NAME OF DEPOSITORY
                                                      PARTICIPANT]
                                                     [Participant Number]

                                                     By:_____________________
                                                        Name:
                                                        Title:

                                                        [Address]
                                                        Telephone:
                                                        Facsimile:


                                      B-1-2

                                                                     EXHIBIT B-2


                             Form of Exercise Notice
          for Warrants Represented by a Definitive Warrant Certificate

[NAME OF WARRANT AGENT],
 as Warrant Agent
[address]
Facsimile:  ________________
Telephone:  ________________

Attention:

      Re:   Exercise of UBS AG Debt Warrants Expiring ________ __, 200__ (the
"Warrants")

            1.    We refer to the Debt Warrant Agreement, dated as of ________
__, 200__ (the "Debt Warrant Agreement"), between UBS AG (the "Corporation") and
[Name of Warrant Agent], as Warrant Agent (the "Warrant Agent"). We hereby
irrevocably exercise [_____________] Warrants (the "Exercised Warrants") and
deliver to you herewith a Definitive Warrant Certificate or Certificates,
registered in the name of the undersigned, representing a number of Warrants at
least equal to the number of Exercised Warrants and payment of the Exercise
Price as provided in Section 2.01(b) of the Debt Warrant Agreement.

            2.    We hereby acknowledge that if you determine that this Exercise
Notice has not been duly completed or is not in proper form, this Exercise
Notice will be void and of no effect and will be deemed not to have been
delivered.

            3.    We hereby direct you to make payment of amounts payable to us
as a result of the exercise of the Warrants hereunder as follows:

                  [ ]               By cashier's check or an official bank
                                    check;
or

                  [ ]               By wire transfer to the following U.S.
                                    dollar bank account in the United
                                    States:

                                    (Minimum payments of $100,000 only)

                                    Bank:________________________________

                                    Account No.:_________________________

                                    ABA Routing No.:_____________________

                                    Reference:___________________________

            Capitalized terms used herein and not defined have the meanings
assigned to them in the Debt Warrant Agreement.

Dated: ________ __, 200__

                                                     [NAME OF HOLDER]


                                                     By:_____________________
                                                        Name:
                                                        Title:

                                                        [Address]
                                                        Telephone:
                                                        Facsimile:


                                      B-2-2

                                                                       EXHIBIT C


                            Form of Rejection Notice

[NAME OF DEPOSITORY PARTICIPANT OR HOLDER],
[address]
Facsimile:  ________________
Telephone:  ________________

Attention:

      Re:   Exercise of UBS AG Debt Warrants Expiring ________ __, 200__ (the
            "Warrants")

            We refer to the Debt Warrant Agreement, dated as of ________ __,
200__ (the "Debt Warrant Agreement"), between UBS AG (the "Corporation") and the
undersigned, as Warrant Agent (the "Warrant Agent").

            In the case of Exercised Warrants represented by a Global Warrant
Certificate and rejected pursuant to Section 2.02(c)(iv) of the Debt Warrant
Agreement: You are hereby notified that [the Exercise Notice delivered by you
was determined by us not to have been [duly completed] [in proper form]] [we
were not able to verify that you are a Depository Participant of [The Depository
Trust Company] in the manner, and pursuant to the procedures], as set forth in
the Debt Warrant Agreement. Accordingly, we have rejected your Exercise Notice
as being unsatisfactory as to form.

            In the case of Tendered Warrants represented by a Definitive Warrant
Certificate and rejected pursuant to Section 2.02(c)(ii) of the Debt Warrant
Agreement: You are hereby notified that [the Exercise Notice delivered by you
was determined by us not to have been [duly completed] [in proper form]] [the
Definitive Warrant Certificate delivered by you was determined by us not to have
been in proper form], as set forth in the Debt Warrant Agreement. Accordingly,
we have rejected your Exercise Notice as being unsatisfactory as to form.

            Capitalized terms used herein and not defined have the meanings
assigned to them in the Debt Warrant Agreement.

Dated: ________ __, 200__

                                                     [NAME OF WARRANT AGENT],
                                                      as Warrant Agent

                                                     By:________________________
                                                        Name:
                                                        Title:


                                       C-2

                                                                       EXHIBIT D



                        Form of Confirmation of Exercise

[NAME OF DEPOSITORY PARTICIPANT OR HOLDER],
[address]
Facsimile:  ________________
Telephone:  ________________

Attention:

      Re:   Exercise of UBS AG Warrants Expiring ________ __, 200__ (the
            "Warrants")

            We refer to the Debt Warrant Agreement, dated as of ________ __,
200__ (the "Debt Warrant Agreement"), between UBS AG (the "Corporation") and the
undersigned, as Warrant Agent (the "Warrant Agent").

            We hereby confirm receipt of your Exercise Notice with respect to
____________ Warrants (the "Exercised Warrants"), and the [Definitive Warrant
Certificates representing the] Warrants relating thereto, which Exercise Notice
[and Definitive Warrant Certificates] we have found to be duly completed and in
good order[, and we have verified, in the manner provided in the Debt Warrant
Agreement, that you are a Depository Participant].

            Capitalized terms used herein and not defined have the meanings
assigned to them in the Debt Warrant Agreement.

Dated: ________ __, 200__

                                                     [NAME OF WARRANT AGENT],
                                                      as Warrant Agent

                                                     By:________________________
                                                        Name:
                                                        Title: