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                                                                  EXHIBIT 4.9




            [FORM OF DEBT WARRANT AGREEMENT FOR WARRANTS SOLD ALONE]



                     CREDIT SUISSE FIRST BOSTON (USA), INC.
                                 as the Company

                                       and

                              ---------------------
                              as the Warrant Agent

                             DEBT WARRANT AGREEMENT

                             Dated as of ___________

                       Warrants to Purchase ______________


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                                TABLE OF CONTENTS

                                                                            PAGE

                                    ARTICLE I

          ISSUANCE OF WARRANTS AND EXECUTION AND DELIVERY OF WARRANT
                                  CERTIFICATES

Section 1.01. Issuance of Warrants............................................1
Section 1.02. Execution and Delivery of Warrant Certificates..................1
Section 1.03. Issuance of Warrant Certificates................................2

                                   ARTICLE II

               WARRANT PRICE, DURATION AND EXERCISE OF WARRANTS

Section 2.01. Warrant Price...................................................4
Section 2.02. Duration of Warrants............................................4
Section 2.03. Exercise of Warrants............................................4

                                   ARTICLE III

          OTHER PROVISIONS RELATING TO RIGHTS OF HOLDERS OF WARRANT
                                  CERTIFICATES

Section 3.01. No Rights as Warrant Securityholder Conferred by Warrants
              or Warrant Certificates.........................................7
Section 3.02. Lost, Mutilated, Stolen, or Destroyed Warrant Certificates......7
Section 3.03. Enforcement of Rights...........................................8
Section 3.04. Merger, Consolidation, Conveyance or Transfer...................8

                                   ARTICLE IV

                              EXCHANGE AND TRANSFER

Section 4.01. Exchange and Transfer...........................................9
Section 4.02. Treatment of Holders of Warrant Certificates....................9
Section 4.03. Cancellation of Warrant Certificates...........................10

                                    ARTICLE V

                          CONCERNING THE WARRANT AGENT

Section 5.01. Warrant Agent..................................................10
Section 5.02. Conditions of Warrant Agent's Obligations......................11
Section 5.03. Resignation and Appointment of Successor.......................12

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                                TABLE OF CONTENTS

                                   (CONTINUED)

                                                                            PAGE


                                   ARTICLE VI

                                  MISCELLANEOUS

Section 6.01. Amendment......................................................14
Section 6.02. Notices and Demands to the Company and Warrant Agent...........14
Section 6.03. Addresses......................................................15
Section 6.04. Applicable Law.................................................15
Section 6.05. Delivery of Prospectus.........................................15
Section 6.06. Obtaining of Governmental Approval.............................15
Section 6.07. Persons Having Rights under Warrant Agreement..................15
Section 6.08. Headings.......................................................15
Section 6.09. Counterparts...................................................15
Section 6.10. Inspection of Agreement........................................15
Section 6.11. Notices to Holders of Warrants.................................16

EXHIBIT A: Form of Warrant Certificate......................................A-1


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                             DEBT WARRANT AGREEMENT

            THIS AGREEMENT dated as of _____ between CREDIT SUISSE FIRST BOSTON
(USA), INC., a corporation duly organized and existing under the laws of the
State of Delaware (the "Company"), and ________, a [bank] [trust company] duly
incorporated and existing under the laws of _______, as Warrant Agent (the
"Warrant Agent"),

                            W I T N E S S E T H :

            WHEREAS, the Company has entered into a senior indenture dated as of
June 1, 2001 (the "Senior Indenture") between the Company and The Chase
Manhattan Bank, as trustee (the "Senior Indenture Trustee") and a subordinated
indenture dated as of ___________ (the "Subordinated Indenture" and together
with the Senior Indenture, "Indentures" or "Indenture") between the Company and
The Chase Manhattan Bank, as trustee (the "Subordinated Indenture Trustee" and
together with the Senior Indenture Trustee, the "Trustee"), providing for the
issuance from time to time of its unsecured debt securities to be issued in one
or more series as provided in the Indenture; and

            WHEREAS, the Company proposes to sell [title of such debt securities
being offered] (the "Offered Securities") with one or more warrants (the
"Warrants") representing the right to purchase [title of such debt securities
purchasable through exercise of Warrants] (the "Warrant Securities"), the
Warrants to be evidenced by warrant certificates issued pursuant to this
Agreement (the "Warrant Certificates"); and

            WHEREAS, the Company desires the Warrant Agent to act on behalf of
the Company in connection with the issuance, transfer, exchange, exercise and
replacement of the Warrant Certificates, and in this Agreement wishes to set
forth, among other things, the form[s] and provisions of the Warrant
Certificates and the terms and conditions on which they may be issued,
transferred, exchanged, exercised and replaced;

            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 EXECUTION AND DELIVERY OF WARRANT CERTIFICATES

            Section 1.01. ISSUANCE OF WARRANTS. The Warrants shall be evidenced
by one or more Warrant Certificates. Each Warrant evidenced thereby shall
represent the right, subject to the provisions contained herein and therein, to
purchase a Warrant Security in the principal amount of _____________.

            Section 1.02. EXECUTION AND DELIVERY OF WARRANT CERTIFICATES. Each
Warrant, whenever issued, shall be evidenced by a Warrant Certificate in
registered form [or a global Warrant Certificate in bearer form (the "Global
Warrant Certificate")] [the form to be the same as that of the Warrant Security
in connection with which the Warrant Certificate is issued],

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substantially in the form[s] set forth in Exhibit A [and Exhibit B,
respectively,] hereto, shall be dated ______ and may have such letters, numbers
or other marks of identification or designation and such legends or endorsements
printed, lithographed or engraved thereon as the officers of the Company
executing the same may approve (execution thereof to be conclusive evidence of
such approval) and as 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 stock
exchange on which the Warrants may be listed, or to conform to usage. The
chairman of the board of directors, the chief executive officer, the president,
the chief financial officer, the chief administrative officer, the chief
accounting officer or any Managing Director and the treasurer or any assistant
treasurer or the secretary or any assistant secretary shall execute the Warrant
Certificates for the Company by facsimile or manual signature in the name and on
behalf of the Company. The seal of the Company, if any, shall be reproduced on
the Warrant Certificates. If an officer whose signature is on a Warrant
Certificate no longer holds that office at the time the Warrant Certificate is
authenticated, the Warrant Certificate shall nevertheless be valid.

            No Warrant Certificate shall be valid for any purpose, and no
Warrant evidenced thereby shall be exercisable, until such Warrant Certificate
has been countersigned by the Warrant Agent by manual signature. Such signature
by the Warrant Agent upon any Warrant Certificate executed by the Company shall
be conclusive evidence, and the only evidence, that the Warrant Certificate so
countersigned has been duly issued hereunder.

            [The Global Warrant Certificate shall be and remain subject to the
provisions of this Agreement until such time as all of the Warrants evidenced
thereby shall have been duly exercised or shall have expired or been cancelled
in accordance with the terms thereof.]

            In case any officer of the Company who shall have signed any of the
Warrant Certificates either manually or by facsimile signature shall cease to be
such officer before the Warrant Certificates so signed shall have been
countersigned and delivered by the Warrant Agent, such Warrant Certificates may
be countersigned and delivered notwithstanding that the person who signed such
Warrant Certificates ceased to be such officer of the Company; and any Warrant
Certificate may be signed on behalf of the Company by such persons as, at the
actual date of the execution of such Warrant Certificate, shall be the proper
officers of the Company, although at the date of the execution of this Agreement
any such person was not such officer.

            The term "Holder", when used with respect to any Warrant Certificate
[in registered form], shall mean any 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. [The term "Holder", when used with respect to
the Global Warrant Certificate, shall mean the bearer thereof.]

            Section 1.03. ISSUANCE OF WARRANT CERTIFICATES. Warrant Certificates
evidencing the right to purchase an aggregate principal amount not exceeding
_____ aggregate principal amount of Warrant Securities (except as provided in
Sections 2.03, 3.02 and 4.01) may be executed by the Company and delivered to
the Warrant Agent upon the execution of this

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Warrant Agreement or from time to time thereafter. The Warrant Agent shall, upon
receipt of Warrant Certificates duly executed on behalf of the Company,
countersign Warrant Certificates evidencing ____Warrants representing the right
to purchase up to _____ aggregate principal amount of Warrant Securities and
shall[, in the case of Warrant Certificates in registered form,] deliver such
Warrant Certificates to or upon the order of the Company [and, in the case of
the Global Warrant Certificate, upon the order of the Company, deposit the
Global Warrant Certificate with ____________, as common depositary (the "Common
Depositary") for Morgan Guaranty Trust Company of New York, Brussels office (or
any successor), as operator of the Euroclear System (the "Euroclear Operator"),
and for Clearstream Banking societe anonyme ("Clearstream") for credit to the
accounts of persons appearing from time to time on the records of the Euroclear
Operator or of Clearstream as being entitled to any portion thereof. [The Global
Warrant Certificate shall be held by the Common Depositary outside the United
Kingdom.]] Subsequent to such original issuance of the Warrant Certificates, the
Warrant Agent shall countersign a Warrant Certificate only if the Warrant
Certificate is issued in exchange or substitution for one or more previously
countersigned Warrant Certificates or [, with respect to Warrant Certificates in
registered form,] in connection with their transfer as hereinafter provided or
as provided in the antepenultimate paragraph of Section 2.03].

            Pending the preparation of definitive Warrant Certificates [in
registered form] evidencing Warrants, the Company may execute and the Warrant
Agent shall countersign and deliver temporary Warrant Certificates [in
registered form] evidencing such Warrants (printed, lithographed, typewritten or
otherwise produced, in each case in form satisfactory to the Warrant Agent).
Such temporary Warrant Certificates shall be issuable substantially in the form
of the definitive Warrant Certificates [in registered form] but with such
omissions, insertions and variations as may be appropriate for temporary Warrant
Certificates, all as may be determined by the Company with the concurrence of
the Warrant Agent. Such temporary Warrant Certificates may contain such
reference to any provisions of this Warrant Agreement as may be appropriate.
Every such temporary Warrant Certificate shall be executed by the Company and
shall be countersigned by the Warrant Agent upon the same conditions and in
substantially the same manner, and with like effect, as the definitive Warrant
Certificates [in registered form]. Without unreasonable delay, the Company shall
execute and shall furnish definitive Warrant Certificates [in registered form]
and thereupon such temporary Warrant Certificates may be surrendered in exchange
therefor without charge pursuant to and subject to the provisions of Section
4.01, and the Warrant Agent shall countersign and deliver in exchange for such
temporary Warrant Certificates definitive Warrant Certificates [in registered
form] of authorized denominations evidencing a like aggregate number of Warrants
evidenced by such temporary Warrant Certificates. Until so exchanged, such
temporary Warrant Certificates shall be entitled to the same benefits under this
Warrant Agreement as definitive Warrant Certificates [in registered form].

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                                   Article II

               WARRANT PRICE, DURATION AND EXERCISE OF WARRANTS

            Section 2.01. WARRANT PRICE. On _______, 20__ the exercise price of
each Warrant will be $___. During the period from _______, 20__, through and
including ____, 20__, the exercise price of each Warrant will be $___ plus
[accrued amortization of the original issue discount] [accrued interest] from
________, 20__. On _____, 20__, the exercise price of each Warrant will be $___.
During the period from _______, 20__ through and including _______, 20__, the
exercise price of each Warrant will be $___ plus [accrued amortization of the
original issue discount] [accrued interest] from ________, 20__ . [In each case,
the original issue discount will be amortized at a ___% annual rate, computed on
an annual basis using the "interest" method and using a 360-day year consisting
of twelve 30-day months]. Such exercise price of Warrant Securities is referred
to in this Agreement as the "Warrant Price". [The original issue discount for
each principal amount of Warrant Securities is ______].

            Section 2.02. DURATION OF WARRANTS. Subject to Section 4.03(b), each
Warrant may be exercised [in whole but not in part] [in whole or in part] [at
any time, as specified herein, on or after [the date thereof] [______, 20__] and
at or before [time, location] on _______, 20__ (each day during such period may
hereinafter be referred to as an "Exercise Date")] [on [list of specific dates]
(each, an "Exercise Date")], or such later date as the Company may designate by
notice to the Warrant Agent and the Holders of Warrant Certificates [in
registered form and to the beneficial owners of the Global Warrant Certificate]
(the "Expiration Date"). Each Warrant not exercised at or before [time,
location] on the Expiration Date shall become void, and all rights of the Holder
[and any beneficial owners] of the Warrant Certificate evidencing such Warrant
under this Agreement shall cease.

            Section 2.03. EXERCISE OF WARRANTS. [With respect to Warrants
evidenced by Warrant Certificates in registered form, during] [During] the
period specified in Section 2.02, any whole number of Warrants may be exercised
by providing certain information as set forth on the reverse side of the Warrant
Certificates evidencing such Warrants and by paying in full [in lawful money of
the United States of America] [in applicable currency] [in cash] [by certified
check or official bank check or by bank wire transfer, in each case,] [by bank
wire transfer] [in immediately available funds,] the Warrant Price for each
Warrant exercised (plus accrued interest, if any, on the Warrant Securities to
be issued upon exercise of such Warrant from and including the Interest Payment
Date (as defined in the Indenture), if any, in respect of such Warrant
Securities immediately preceding the Exercise Date to and including the Exercise
Date (unless the Exercise Date is after the Regular Record Date (as defined in
the Indenture), if any, for such Interest Payment Date, but on or before the
immediately succeeding Interest Payment Date for such Warrant Securities, in
which event no such accrued interest shall be payable)) to the Warrant Agent at
its corporate trust office at [address] [or at __________], provided that such
exercise is subject to receipt within five business days of such [payment] [wire
transfer] by the Warrant Agent of the Warrant Certificate evidencing each
Warrant exercised with the form of election to purchase Warrant Securities set
forth on the reverse side of the Warrant Certificate properly completed and duly
executed.

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            [With respect to Warrants evidenced by the Global Warrant
Certificate, during the period specified in Section 2.02, any whole number of
Warrants may be exercised by the Holder by presentation to the Warrant Agent at
its office at [address located outside the United States [and the United
Kingdom]], at or prior to [time], on any day on which the Warrants are
exercisable, of (i) the Global Warrant Certificate (or written confirmation
reasonably satisfactory to the Warrant Agent that the Global Warrant Certificate
is held by the Euroclear Operator and Clearstream and will be duly endorsed to
reflect the exercise of Warrants by the Euroclear Operator and Clearstream),
(ii) a duly executed certification from the Euroclear Operator or Clearstream,
as the case may be, substantially in the form set forth in Exhibit C hereto and
(iii) payment in full [in lawful money of the United States of America] [in
applicable currency] [in cash] [by certified check or official bank check or by
bank wire transfer, in each case,] [by bank wire transfer] [in immediately
available funds,] of the Warrant Price for each Warrant exercised (plus accrued
interest, if any, on the Warrant Securities to be issued upon exercise of such
Warrant from and including the Interest Payment Date, if any, in respect of such
Warrant Securities immediately preceding the Exercise Date to and including the
Exercise Date (unless the Exercise Date is after the Regular Record Date, if
any, for such Interest Payment Date, but on or before the immediately succeeding
Interest Payment Date for such Warrant Securities, in which event no such
accrued interest shall be payable in respect of Warrant Securities to be issued
in registered form)). Notwithstanding the foregoing, the Holder may exercise
Warrants as aforesaid on the Expiration Date at any time prior to [time] in
[city of Warrant Agent's office]. Any Warrants exercised as set forth in this
paragraph shall be deemed exercised at the [country] office of the Warrant
Agent.]

            [The Warrant Agent shall retain each certificate received by it from
the Euroclear Operator of Clearstream through the Expiration Date (or such
earlier date by which all of the Warrants may have been exercised or cancelled)
and thereafter shall dispose of them or deliver them to the Company pursuant to
the instructions of the Company.]

            [The delivery to the Warrant Agent by the Euroclear Operator or
Clearstream of any certification referred to above may be relied upon by the
Company, the Warrant Agent and the Trustee as conclusive evidence that a
corresponding certificate or certificates substantially in the form of Exhibit D
hereto has or have been delivered to the Euroclear Operator or Clearstream, as
the case may be.]

            [The Company will maintain in [location] (or in such other city [in
western Europe] as the Company may deem advisable), until the right to exercise
the Warrants shall expire or be earlier cancelled as hereinafter provided, an
agency where the Global Warrant Certificate may be presented for exercise of the
Warrants represented thereby and notices and demands to or upon the Company in
respect of the Warrants or of this Agreement may be made.]

            The date on which payment in full of the Warrant Price (plus any
such accrued interest) is received by the Warrant Agent shall, subject to
receipt of the Warrant Certificate [in registered form or, as the case may be,
the Global Warrant Certificate and the certification of Euroclear Operator or
Clearstream] as aforesaid, be deemed to be the date on which the Warrant is
exercised. The Warrant Agent shall deposit all funds received by it in payment
for the exercise

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of Warrants in an account of the Company maintained with it (or in such other
account as may be designated by the Company) and shall advise the Company, by
telephone or by facsimile transmission or other form of electronic communication
available to both parties, at the end of each day on which a payment for the
exercise of Warrants is received of the amount so deposited to its account. The
Warrant Agent shall promptly confirm such advice to the Company in writing.

            If a day on which Warrants may be exercised in the city in which
such Warrants are to be exercised shall be a Saturday or Sunday or a day on
which banking institutions in such city are authorized or required to be closed,
then, notwithstanding any other provision of this Agreement or the Warrant
Certificate evidencing such Warrants, but subject to the limitation that no
Warrant may be exercised after the Expiration Date, the Warrants shall be
exercisable on the next succeeding day which in such city is not a Saturday or
Sunday or a day on which banking institutions in such city are authorized or
required to be closed.

            The Warrant Agent shall, from time to time, as promptly as
practicable, advise the Company [and][,] the Trustee [and the Common Depositary
at [both] its London and [location] office[s]] in writing [(which, in the case
of exercised Warrants represented by the Global Warrant Certificate, shall be
tested telex with appropriate answerback received,)] of (i) the number of
Warrants exercised, (ii) the instructions of each Holder of the Warrant
Certificates [in registered form] evidencing such Warrants [or of the Euroclear
Operator or Clearstream, as the case may be,] with respect to delivery of the
Warrant Securities to be issued upon such exercise, (iii) delivery of any
Warrant Certificates [in registered form] evidencing the balance, if any, of the
Warrants remaining after such exercise, and (iv) such other information as the
Company or the Trustee shall reasonably require. [In addition, in the case of
exercised Warrants evidenced by the Global Warrant Certificate, the Warrant
Agent shall, as promptly as practicable, endorse, or cause the Common
Depositary, [location] office, or one of the Warrant Agent's agents to endorse,
Schedule A annexed to the Global Warrant Certificate to reflect the exercise of
such Warrants and, if applicable, return the Global Warrant Certificate to the
Common Depositary or to its order.]

            As soon as practicable after the exercise of any Warrant [evidenced
by a Warrant Certificate in registered form], but subject to receipt by the
Warrant Agent of the Warrant Certificate evidencing such Warrant as provided in
this Section, the Company shall issue, pursuant to the Indentures, in authorized
denominations to or upon the order of the Holder of the Warrant Certificate
evidencing each Warrant, the Warrant Securities to which such Holder is
entitled, in fully registered form, registered in such name or names as may be
directed by such Holder. If fewer than all of the Warrants evidenced by such
Warrant Certificate are exercised, the Company shall execute, and an authorized
officer of the Warrant Agent shall manually countersign and deliver, a new
Warrant Certificate [in registered form] evidencing the number of such Warrants
remaining unexercised.

            [As soon as practicable after the exercise of any Warrant evidenced
by the Global Warrant Certificate, the Company shall issue, pursuant to the
Indenture, the Warrant Securities issuable upon such exercise, in authorized
denominations (i) in fully registered form, registered

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in such name or names as may be directed by the Euroclear Operator or
Clearstream, as the case may be, to or upon order of the Euroclear Operator or
Clearstream, as the case may be, or (ii) in bearer form to the Common Depositary
to be held for the account of the Euroclear Operator or Clearstream, as the case
may be, together with a written confirmation substantially in form of Exhibit E
hereto; provided, however, that no Warrant Security in bearer form shall be
mailed or otherwise delivered to any location in the United States of America,
its territories or possessions or areas subject to its jurisdiction or the
Commonwealth of Puerto Rico.]

            The Company 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 issuance of the Warrant Securities, and in the event that any
such transfer is involved, the Company shall not be required to issue or deliver
any Warrant Security until such tax or other charge shall have been paid or it
has been established to the Company's satisfaction that no such tax or other
charge is due.

                                  Article III

    OTHER PROVISIONS RELATING TO RIGHTS OF HOLDERS OF WARRANT CERTIFICATES

            Section 3.01. NO RIGHTS AS WARRANT SECURITYHOLDER CONFERRED BY
WARRANTS OR WARRANT CERTIFICATES. No Warrant Certificate or Warrant evidenced
thereby shall entitle the Holder of any beneficial owner thereof to any of the
rights of a holder or beneficial owner of Warrant Securities, including, without
limitation, the right to receive the payment of principal of (premium, if any)
or interest, if any, on Warrant Securities or to enforce any of the covenants in
the Indenture.

            Section 3.02. LOST, MUTILATED, STOLEN, OR DESTROYED WARRANT
CERTIFICATES. Upon receipt by the Warrant Agent of evidence reasonably
satisfactory to it and the Company of the ownership of and the loss, mutilation,
theft or destruction of any Warrant Certificate and of such security or
indemnity as may be required by the Company and the Warrant Agent to hold each
of them and any agent of them harmless and, in the case of mutilation of a
Warrant Certificate, upon surrender thereof to the Warrant Agent for
cancellation, then, in the absence of notice to the Company or the Warrant Agent
that such Warrant Certificate has been acquired by a bona fide purchaser, the
Company shall execute, and an authorized officer of the Warrant Agent shall
manually countersign and deliver, in exchange for or in lieu of the lost,
mutilated, stolen or destroyed Warrant Certificate, a new Warrant Certificate of
the same tenor and evidencing a like number of Warrants[; provided, however,
that any Global Warrant Certificate shall be so delivered only to the Common
Depositary.] Upon the issuance of any new Warrant Certificate under this
Section, the Company may require the payment of a sum sufficient to cover any
stamp or other 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) in connection therewith. Every substitute Warrant Certificate executed
and delivered pursuant to this Section in lieu of any lost, mutilated, stolen or
destroyed Warrant

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Certificate shall represent an additional contractual obligation of the Company,
whether or not the lost, stolen or destroyed Warrant Certificate shall be at any
time enforceable by anyone, and shall be entitled to the benefits of this
Agreement equally and proportionately with any and all other Warrant
Certificates duly executed and delivered hereunder. The provisions of this
Section are exclusive and shall preclude (to the extent lawful) all other rights
and remedies with respect to the replacement of lost, mutilated, stolen or
destroyed Warrant Certificates.

            Section 3.03. ENFORCEMENT OF RIGHTS. Notwithstanding any of the
provisions of this Agreement, any Holder of a Warrant Certificate [in registered
form or the beneficial owner of any Warrant evidenced by the Global Warrant
Certificate], without the consent of [the Common Depositary,] the Warrant Agent,
the relevant Trustee, the holder of any Offered Securities of the Holder of any
other Warrant Certificate, may, in its own behalf and for its own benefit,
enforce, and may institute and maintain any suit, action or proceeding against
the Company suitable to enforce, or otherwise in respect of, its right to
exercise its Warrants in the manner provided in its Warrant Certificate [or the
Global Warrant Certificate, as the case may be,] and in this Agreement. [Neither
the Company nor the Warrant Agent shall be required to treat any person as a
beneficial owner of any Warrant evidenced by the Global Warrant Certificate
unless such person is so certified as such a beneficial owner by the Euroclear
Operator or Clearstream.]

            Section 3.04. MERGER, CONSOLIDATION, CONVEYANCE OR TRANSFER. (a) If
at any time there shall be a merger or consolidation of the Company or a
conveyance or transfer of its property and assets substantially as an entirety
as permitted under the Indentures, then in any such event the successor or
assuming corporation referred to therein shall succeed to and be substituted for
the Company, with the same effect, subject to the Indentures, as if it had been
named herein and in the Warrant Certificates as the Company; the Company shall
thereupon, except in the case of a transfer by way of lease, be relieved of any
further obligation hereunder and under the Warrants and the Warrant
Certificates, and the Company as the predecessor corporation, except in the case
of a transfer by way of lease, may thereupon or at any time thereafter be
dissolved, wound up or liquidated. Such successor or assuming corporation may
thereupon cause to be signed, and may issue either in its own name or in the
name of the Company, Warrant Certificates evidencing any or all of the Warrants
issuable hereunder which theretofore shall not have been signed by the Company,
and may execute and deliver Warrant Securities in its own name pursuant to the
Indentures, in fulfillment of its obligations to deliver Warrant Securities upon
exercise of the Warrants. All the Warrants so issued shall in all respects have
the same legal rank and benefit under this Agreement as the Warrants theretofore
or thereafter issued in accordance with the terms of this Agreement as though
all of such Warrants had been issued at the date of the execution hereof. In any
case of any such merger, consolidation, conveyance or transfer, such changes in
phraseology and form (but not in substance) may be made in the Warrant
Certificates representing the Warrants thereafter to be issued as may be
appropriate.

            (b) The Warrant Agent may receive a written opinion of legal counsel
      (who shall be acceptable to the Warrant Agent) as conclusive evidence that
      any such merger, consolidation, conveyance or transfer complies with the
      provisions of this Section and the Indentures.

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                                   Article IV

                              EXCHANGE AND TRANSFER

            Section 4.01. EXCHANGE AND TRANSFER. (a) Upon surrender at the
corporate trust office of the Warrant Agent at [address] [or ____], Warrant
Certificates [in registered form] evidencing Warrants may be exchanged for
Warrant Certificates [in registered form] in other authorized denominations
evidencing such Warrants or the transfer thereof may be registered in whole or
in part; provided, however, that such other Warrant Certificates shall evidence
the same aggregate number of Warrants as the Warrant Certificates so
surrendered.

            (b) The Warrant Agent shall keep, at its corporate trust office at
      [address] [and at _______], books in which, subject to such reasonable
      regulations as it may prescribe, it shall register Warrant Certificates
      [in registered form] and exchanges and transfers of outstanding Warrant
      Certificates [in registered form] upon surrender of such Warrant
      Certificates to the Warrant Agent at its corporate trust office at
      [address] or [_____] for exchange or registration of transfer, properly
      endorsed [or accompanied by appropriate instruments of registration of
      transfer and written instructions for transfer, all in form satisfactory
      to the Company and the Warrant Agent.]

            (c) No service charge shall be made for any exchange or registration
      of transfer of Warrant Certificates [in registered form], but the Company
      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
      exchange or registration of transfer.

            (d) Whenever any Warrant Certificates [in registered form], are so
      surrendered for exchange or registration of transfer, an authorized
      officer of the Warrant Agent shall manually countersign and deliver to the
      person or persons entitled thereto a Warrant Certificate or Warrant
      Certificates [in registered form], duly authorized and executed by the
      Company, as so requested. The Warrant Agent shall not effect any exchange
      or registration of transfer which will result in the issuance of a Warrant
      Certificate [in registered form], evidencing a fraction of a Warrant or a
      number of full Warrants and a fraction of a Warrant.

            (e) All Warrant Certificates [in registered form], issued upon any
      exchange or registration of transfer of Warrant Certificates shall be the
      valid obligations of the Company, evidencing the same obligations, and
      entitled to the same benefits under this Agreement, as the Warrant
      Certificates surrendered for such exchange or registration or transfer.

            Section 4.02. TREATMENT OF HOLDERS OF WARRANT CERTIFICATES. [With
respect to the Global Warrant Certificate, the Holder thereof may be treated by
the Company, the Warrant Agent and all other persons dealing with such Holder as
the absolute owner thereof for any purpose and as the person entitled to
exercise the rights represented by the Warrants evidenced thereby, any notice to
the contrary notwithstanding.] [With respect to Warrant Certificates in

                                       9
<Page>

registered form, each] [Each] Holder of a Warrant Certificate, by accepting the
same, consents and agrees with the Company, the Warrant Agent and every
subsequent Holder of such Warrant Certificate that until the transfer of such
Warrant Certificate is registered on the books of such Warrant Agent, the
Company and the Warrant Agent may treat the registered Holder of such Warrant
Certificate as the absolute owner thereof for any purpose and as the person
entitled to exercise the rights represented by the Warrants evidenced thereby,
any notice to the contrary notwithstanding.

            Section 4.03. CANCELLATION OF WARRANT CERTIFICATES. (a) Any Warrant
Certificate surrendered for exchange or registration of transfer or exercise of
the Warrants evidenced thereby shall, if surrendered to the Company, be
delivered to the Warrant Agent, and all Warrant Certificates surrendered or so
delivered to the Warrant Agent shall be promptly cancelled by the Warrant Agent
and shall not be reissued and, except as expressly permitted by this Agreement,
no Warrant Certificate shall be issued hereunder in exchange therefor or in lieu
thereof. The Warrant Agent shall cause all cancelled Warrant Certificates to be
destroyed and shall deliver a certificate of such destruction to the Company.

            (b) If the Company notifies the relevant Trustee of its election to
      redeem [, as a whole but not in part,] the Warrant Securities pursuant to
      the Indenture or the terms thereof, the Company may elect, and shall give
      notice to the Warrant Agent of its election, to cancel the unexercised
      Warrants, the Warrant Certificates and the rights evidenced thereby.
      Promptly after receipt of such notice by the Warrant Agent, the Company
      shall, or, at the Company's request, the Warrant Agent shall in the name
      of and at the expense of the Company, give notice of such cancellation to
      the Holders of the Warrant Certificates [in registered form and to the
      beneficial owners of the Global Warrant Certificate (except that such
      notice shall be required to be published only once)], such notice to be so
      given not less than 30 nor more than 60 days prior to the date fixed for
      the redemption of the Warrant Securities pursuant to Indenture or the
      terms thereof. The unexercised Warrants, the Warrant Certificates and the
      rights evidenced thereby shall be cancelled and become void on the 15th
      day prior to such date fixed for redemption.

                                   Article V

                          CONCERNING THE WARRANT AGENT

            Section 5.01. WARRANT AGENT. The Company hereby appoints ______ as
Warrant Agent of the Company in respect of the Warrants and the Warrant
Certificates upon the terms and subject to the conditions herein and in the
Warrant Certificates set forth; and _______ hereby accepts such appointment. The
Warrant Agent shall have the powers and authority granted to and conferred upon
it in the Warrant Certificates and herein and such further powers and authority
to act on behalf of the Company as the Company may hereafter grant to or confer
upon it. All of the terms and provisions with respect to such powers and
authority contained in the Warrant Certificates are subject to and governed by
the terms and provisions hereof.

                                       10
<Page>

            Section 5.02. CONDITIONS OF WARRANT AGENT'S OBLIGATIONS. The Warrant
Agent accepts its obligations herein set forth upon the terms and conditions
hereof, including the following, to all of which the Company agrees and to all
of which the rights hereunder of the Holders from time to time of the Warrant
Certificates shall be subject:

            (a) COMPENSATION AND INDEMNIFICATION. The Company agrees promptly to
      pay the Warrant Agent the compensation to be agreed upon with the Company
      for all services rendered by the Warrant Agent and to reimburse the
      Warrant Agent for reasonable out-of-pocket expenses (including reasonable
      attorneys' fees) incurred by the Warrant Agent without negligence, bad
      faith or breach of this Agreement on its part in connection with the
      services rendered hereunder by the Warrant Agent. The Company also agrees
      to indemnify the Warrant Agent for, and to hold it harmless against, any
      loss, liability or expense incurred without negligence or bad faith on the
      part of the Warrant Agent, arising out of or in connection with its acting
      as Warrant Agent hereunder, as well as the reasonable costs and expenses
      of defending against any claim of such liability.

            (b) AGENT FOR THE COMPANY. In acting under this Agreement and in
      connection with the Warrants and the Warrant Certificates, the Warrant
      Agent is acting solely as agent of the Company and does not assume any
      obligation or relationship of agency or trust for or with any of the
      Holders of Warrant Certificates or beneficial owners of Warrants.

            (c) COUNSEL. The Warrant Agent may consult with counsel satisfactory
      to it in its reasonable judgment, and the advice 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 the advice of such counsel.

            (d) DOCUMENTS. The Warrant Agent shall be protected and shall incur
      no liability for or in respect of any action taken or thing suffered by it
      in reliance upon any Warrant Certificate, 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.

            (e) CERTAIN TRANSACTIONS. The Warrant Agent, and its officers,
      directors and employees, may become the owner of, or acquire any interest
      in, Warrants, 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 Company and may act on, or as depositary,
      trustee or agent for, any committee or body of holders of Warrant
      Securities or other obligations of the Company 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.

                                       11
<Page>

            (f) NO LIABILITY FOR INTEREST. The Warrant Agent shall have no
      liability for interest on any monies at any time received by it pursuant
      to any of the provisions of this Agreement or of the Warrant Certificates.

            (g) NO LIABILITY FOR INVALIDITY. The Warrant Agent shall not be
      under any responsibility with respect to the validity or sufficiency of
      this Agreement or the execution and delivery hereof (except the due
      authorization to execute this Agreement and the due execution and delivery
      hereof by the Warrant Agent) or with respect to the validity or execution
      of any Warrant Certificates (except its countersignature thereof).

            (h) NO LIABILITY FOR RECITALS. The recitals contained herein shall
      be taken as the statements of the Company and the Warrant Agent assumes no
      liability for the correctness of the same.

            (i) NO IMPLIED OBLIGATIONS. The Warrant Agent shall be obligated to
      perform only such duties as are herein and in the Warrant Certificates
      specifically set forth and no implied duties or obligations shall be read
      into this Agreement or the Warrant Certificates against the Warrant Agent.
      The Warrant Agent shall not be under any obligation to take any action
      hereunder which may tend to involve it in any expense or liability, the
      payment of which within a reasonable time is not, in its reasonable
      opinion, assured to it. The Warrant Agent shall not be accountable or
      under any duty or responsibility for the use by the Company of any of the
      Warrant Certificates countersigned by the Warrant Agent and delivered by
      it to the Company pursuant to this Agreement or for the application by the
      Company of the proceeds of the Warrant Certificates. The Warrant Agent
      shall have no duty or responsibility in case of any default by the Company
      in the performance of its covenants or agreements contained herein or in
      the Warrant Certificates or in the case of the receipt of any written
      demand from a Holder of a Warrant Certificate with respect to such
      default, including, without limiting the generality of the foregoing, any
      duty or responsibility to initiate or attempt to initiate any proceedings
      at law or otherwise or, except as provided in Section 6.02, to make any
      demand upon the Company.

            Section 5.03. RESIGNATION AND APPOINTMENT OF SUCCESSOR. (a) The
Company agrees, for the benefit of the Holders from time to time of the Warrant
Certificates, that there shall at all times be a Warrant Agent hereunder until
all the Warrants have been exercised or are no longer exercisable.

            (b) The Warrant Agent may at any time resign as such by giving
      written notice of its resignation to the Company, specifying the desired
      date on which its resignation shall become effective; provided, however,
      that such date shall be not less than 90 days after the date on which such
      notice is given unless the Company agrees to accept shorter notice. Upon
      receiving such notice of resignation, the Company shall promptly appoint a
      successor Warrant Agent (which shall be a bank or trust company in good
      standing, authorized under the laws of the jurisdiction of its
      organization to exercise corporate trust powers) by written instrument in
      duplicate signed on behalf of the

                                       12
<Page>

      Company, one copy of which shall be delivered to the resigning Warrant
      Agent and one copy to the successor Warrant Agent. The Company may, at any
      time and for any reason, remove the Warrant Agent and appoint a successor
      Warrant Agent (qualified as aforesaid) by written instrument in duplicate
      signed on behalf of the Company and specifying such removal and the date
      when it is intended to become effective, one copy of which shall be
      delivered to the Warrant Agent being removed and one copy to the successor
      Warrant Agent. Any resignation or removal of the Warrant Agent and any
      appointment of a successor Warrant Agent shall become effective upon
      acceptance of appointment by the successor Warrant Agent as provided in
      this subsection (b). In the event a successor Warrant Agent has not been
      appointed and accepted its duties within 90 days of the Warrant Agent's
      notice of resignation, the Warrant Agent may apply to any court of
      competent jurisdiction for the designation of a successor Warrant Agent.
      Upon its resignation or removal, the Warrant Agent shall be entitled to
      the payment by the Company of the compensation and to the reimbursement of
      all reasonable out-of-pocket expenses (including reasonable attorneys'
      fees) incurred by it hereunder as agreed to in Section 5.02(a).

            (c) The Company shall remove the Warrant Agent and appoint a
      successor Warrant Agent if the Warrant Agent (i) shall become incapable of
      acting, (ii) shall be adjudged bankrupt or insolvent, (iii) shall commence
      a voluntary case or other proceeding seeking liquidation, reorganization
      or other relief with respect to it or its debts under any bankruptcy,
      insolvency or other similar law now or hereafter in effect or seeking the
      appointment of a trustee, receiver, liquidator, custodian or other similar
      official of it or any substantial part of its property, (iv) shall consent
      to, or shall have had entered against it a court order for, any such
      relief or to the appointment of or taking possession by any such official
      in any involuntary case or other proceedings commenced against it, (v)
      shall make a general assignment for the benefit of creditors or (vi) shall
      fail generally to pay its debts as they become due. Upon the appointment
      as aforesaid of a successor Warrant Agent and acceptance by it of such
      appointment, the predecessor Warrant Agent shall, if not previously
      disqualified by operation of law, cease to be Warrant Agent hereunder.

            (d) Any successor Warrant Agent appointed hereunder shall execute,
      acknowledge and deliver to its predecessor and the Company an instrument
      accepting such appointment hereunder, and thereupon such successor Warrant
      Agent, without any further act, deed or conveyance, shall become vested
      with all the authority, rights, powers, immunities, duties and obligations
      of such predecessor with like effect as if originally named as Warrant
      Agent hereunder, and such predecessor shall thereupon become obligated to
      transfer, deliver and pay over, and such successor Warrant Agent shall be
      entitled to receive, all monies, securities and other property on deposit
      with or held by such predecessor as Warrant Agent hereunder.

            (e) Any corporation into which the Warrant Agent hereunder may be
      merged or converted or any corporation with which the Warrant Agent may be
      consolidated, or any corporation resulting from any merger, conversion or
      consolidation to which the

                                       13
<Page>

      Warrant Agent shall be a party, or any corporation to which the Warrant
      Agent shall sell or otherwise transfer all or substantially all the assets
      and business of the Warrant Agent, provided that it shall be qualified as
      aforesaid, shall be the successor Warrant Agent under this Agreement
      without the execution or filing of any paper or any further act on the
      part of any of the parties hereto.

                                   Article VI

                                  MISCELLANEOUS

            Section 6.01. AMENDMENT. (a) This Agreement and the terms of the
Warrants and the Warrant Certificates may be amended by the parties hereto,
without the consent of the Holder of any Warrant Certificate or the beneficial
owner of any Warrant, for the purpose of curing any ambiguity, or of curing,
correcting or supplementing any defective or inconsistent provision contained
herein or in the Warrant Certificates, or making any other provisions with
respect to matters or questions arising under this Agreement as the Company and
the Warrant Agent may deem necessary or desirable, provided that such action
shall not affect adversely the interests of the Holders of the Warrant
Certificates or the beneficial owners of Warrants in any material respect.

            (b) The Company and the Warrant Agent may modify or amend this
      Agreement (by means of an agreement supplemental hereto or otherwise) with
      the consent of Warrantholders holding not less than a majority in number
      of the then outstanding Warrants of all series affected by such
      modification or amendment, for any purpose; provided, however, that no
      such modification or amendment that changes the exercise price of the
      Warrants of any series, reduces the amount receivable upon exercise,
      cancellation or expiration of the Warrants other than in accordance with
      the antidilution provisions or other similar adjustment provisions
      included in the terms of the Warrants, shortens the period of time during
      which the Warrants of such series may be exercised, or otherwise
      materially and adversely affects the exercise rights of the affected
      Warrantholders or reduces the percentage of the number of outstanding
      Warrants of such series, the consent of whose holders is required for
      modification or amendment of this Agreement, may be made without the
      consent of each Warrantholder affected thereby. In the case of Warrants
      evidenced by one or more Global Warrant Certificates, the Company 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 holders of beneficial ownership interests in the relevant Global
      Warrant Certificate. Such certification may be provided by participants of
      the Depositary acting on behalf of such beneficial owners of Warrants,
      provided that any such certification is accompanied by a certification
      from the Depositary as to the Warrant holdings of such participants.

            Section 6.02. NOTICES AND DEMANDS TO THE COMPANY AND WARRANT AGENT.
If the Warrant Agent shall receive any notice or demand addressed to the Company
by the Holder of a Warrant Certificate pursuant to the provisions of the Warrant
Certificates, the Warrant Agent shall promptly forward such notice or demand to
the Company.

                                       14
<Page>

            Section 6.03. ADDRESSES. Any communication from the Company to the
Warrant Agent with respect to this Agreement shall be addressed to
______________________, Attention: _________, and any communication from the
Warrant Agent to the Company with respect to this Agreement shall be addressed
to Credit Suisse First Boston (USA), Inc., Eleven Madison Avenue, New York, New
York 10010, Attention: Corporate Treasury Department (or such other address as
shall be specified in writing by the Warrant Agent or by the Company).

            Section 6.04. APPLICABLE LAW. The validity, interpretation and
performance of this Agreement and each Warrant Certificate issued hereunder and
of the respective terms and provisions hereof and thereof shall be governed by,
and construed in accordance with, the laws of the State of New York.

            Section 6.05. DELIVERY OF PROSPECTUS. The Company will furnish to
the Warrant Agent sufficient copies of a prospectus relating to the Warrant
Securities deliverable upon exercise of Warrants (the "Prospectus"), and the
Warrant Agent agrees that upon the exercise of any Warrant, the Warrant Agent
will deliver to the Holder of the Warrant Certificate evidencing such Warrant,
prior to or concurrently with the delivery of the Warrant Securities issued upon
such exercise, a Prospectus. The Warrant Agent shall not, by reason of any such
delivery, assume any responsibility for the accuracy or adequacy of such
Prospectus.

            Section 6.06. OBTAINING OF GOVERNMENTAL APPROVAL. The Company will
from time to time take all action which may be necessary to obtain and keep
effective any and all permits, consents and approvals of governmental agencies
and authorities and securities acts filings under United States federal and
state laws (including without limitation a registration statement in respect of
the Warrants and Warrant Securities under the Securities Act of 1933), which may
be or become requisite in connection with the issuance, sale, transfer and
delivery of the Warrant Certificates, the exercise of the Warrants, the
issuance, sale, transfer and delivery of the Warrant Securities issued upon
exercise of the Warrants or upon the expiration of the period during which the
Warrants are exercisable.

            Section 6.07. PERSONS HAVING RIGHTS UNDER WARRANT AGREEMENT. [Except
as otherwise provided in Section 3.03, nothing] [Nothing] in this Agreement
shall give to any person other than the Company, the Warrant Agent and the
Holders of the Warrant Certificates any right, remedy or claim under or by
reason of this Agreement.

            Section 6.08. HEADINGS. The descriptive headings of the several
Articles and Sections of this Agreement are inserted for convenience only and
shall not control or affect the meaning or construction of any of the provisions
hereof.

            Section 6.09. COUNTERPARTS. This Agreement may be executed in any
number of counterparts, each of which as so executed shall be deemed to be an
original, but such counterparts shall together constitute but one and the Same
instrument.

            Section 6.10. INSPECTION OF AGREEMENT. A copy of this Agreement
shall be available at all reasonable times at the principal corporate trust
office of the Warrant Agent for

                                       15
<Page>

inspection by the Holder of any Warrant Certificate. The Warrant Agent may
require such Holder to submit his Warrant Certificate for inspection by it.

            Section 6.11. NOTICES TO HOLDERS OF WARRANTS. Any notice to Holders
of Warrants evidenced by Warrant Certificates [in registered form] which by any
provisions of this Warrant Agreement is required or permitted to be given shall
be given by first class mail prepaid at such Holder's address as it appears on
the books of the Warrant Agent. [Any notice to beneficial owners of Warrants
evidenced by the Global Warrant Certificate which by any provisions of this
Warrant Agreement is required or permitted to be given shall be given in the
manner provided with respect to Warrant Securities in bearer form in Section
1.06 of the Indenture].



                                       16
<Page>

            IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed and their respective corporate seals to be hereunto affixed and
attested, all as of the date first above written.

                                    CREDIT SUISSE FIRST BOSTON (USA), INC.



[SEAL]                              By:
                                       ---------------------------------
                                       Name:
                                       Title:

Attest:


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


                                    [WARRANT AGENT]



[SEAL]                              By:
                                       ---------------------------------
                                       Name:
                                       Title:

Attest:


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


                                       17
<Page>

                                    EXHIBIT A

                           FORM OF WARRANT CERTIFICATE

                          [FACE OF WARRANT CERTIFICATE]

[Form of Legend if Warrants are not      Prior to __________________, Warrants
immediately exercisable                  evidenced by this Warrant Certificate
                                         cannot be exercised.]


               EXERCISABLE ONLY IF COUNTERSIGNED BY THE WARRANT
                            AGENT AS PROVIDED HEREIN

                    CREDIT SUISSE FIRST BOSTON (USA), INC.
                              WARRANTS TO PURCHASE
                          [Title of Warrant Securities]

                 VOID AFTER [TIME, LOCATION], ON ____________

No.                                                          Warrants
   ---------------                        ------------------

            This certifies that ____________ or registered assigns is the
registered owner of the above indicated number of Warrants, each Warrant
entitling such owner [2:, subject to the registered owner qualifying as a
"Holder" of this Warrant Certificate, as hereinafter defined) to purchase, at
any time [after [time, location] on __________ and] on or before [time,
location], on _____________, _________ shares of [Title of Warrant Securities]
(the "Warrant Securities"), of Credit Suisse First Boston (USA), Inc. (the
"Company") on the following basis: during the period from _____________, through
and including _____________, the exercise price of each Warrant will be
____________; during the period from ____________, through and including
____________, the exercise price of each Warrant will be _________ (the "Warrant
Price"). No adjustment shall be made for any dividends or other distributions,
if any, on any Warrant Securities issuable upon exercise of any Warrant. The
holder may exercise the Warrants evidenced hereby by providing certain
information set forth on the back hereof and by paying in full [in lawful money
of the United States of America][in applicable currency] [in cash] [by certified
check or official bank check or by bank wire transfer, in each case,] [by bank
wire transfer] [in immediately available funds], the Warrant Price for each
Warrant exercised to the Warrant Agent (as hereinafter defined) and by
surrendering this Warrant Certificate, with the purchase form on the back hereof
duly executed, at the corporate trust office of [name of Warrant Agent], or its
successor as warrant agent (the "Warrant Agent"), [or ________], which is, on
the date hereof, at the address specified on the reverse hereof, and upon
compliance with and subject to the conditions set forth herein and in the
Warrant Agreement (as hereinafter defined).

            The term "Holder" as used herein shall mean the person in whose name
at the time this Warrant Certificate shall be registered upon the books to be
maintained by the Warrant Agent for that purpose pursuant to Section 4.01 of the
Warrant Agreement.

                                      A-1
<Page>

            [Any whole number of] [The] Warrants evidenced by this Warrant
Certificate may be exercised to purchase Warrant Securities in registered form.
[Upon any exercise of fewer than all of the Warrants evidenced by this Warrant
Certificate, there shall be issued to the holder hereof a new Warrant
Certificate evidencing the number of Warrants remaining unexercised.]

            This Warrant Certificate is issued under and in accordance with the
Warrant Agreement dated as of ___________ (the "Warrant Agreement") between the
Company and the Warrant Agent and is subject to the terms and provisions
contained in the Warrant Agreement, to all of which terms and provisions the
holder of this Warrant Certificate consents by acceptance hereof. Copies of the
Warrant Agreement are on file at the above-mentioned office of the Warrant Agent
[and at ____________].

            Transfer of this Warrant Certificate may be registered when this
Warrant Certificate is surrendered at the corporate trust office of the Warrant
Agent [or _________] by the registered owner or such owner's assigns, in person
or by an attorney duly authorized in writing, in the manner and subject to the
limitations provided in the Warrant Agreement.

            After countersignature by the Warrant Agent and prior to the
expiration of this Warrant Certificate, this Warrant Certificate may be
exchanged at the corporate trust office of the Warrant Agent [or _________] for
Warrant Certificates representing the same aggregate number of Warrants.

            This Warrant Certificate shall not entitle the holder hereof to any
of the rights of a holder of the Warrant Securities, including, without
limitation, the right to receive payments of dividends or distributions, if any,
on the Warrant Securities or the exercise of any voting rights.

            This Warrant Certificate shall not be valid or binding for any
purpose until countersigned by the Warrant Agent.

                                      A-2
<Page>

            IN WITNESS WHEREOF, Credit Suisse First Boston (USA), Inc. has
caused this instrument to be duly executed.


Dated as of ______________

                                      CREDIT SUISSE FIRST BOSTON (USA), INC.


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


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


Countersigned:


----------------------------------,
as Warrant Agent

By:
   -------------------------------
   Authorized Signatory






                                      A-3
<Page>

                        [REVERSE OF WARRANT CERTIFICATE]

                      Instructions for Exercise of Warrant

            To exercise the Warrants evidenced hereby, the holder must pay [in
United States dollars][in applicable currency] [in cash] [by certified check or
official bank check or by bank wire transfer, in each case] [by bank wire
transfer] [in immediately available funds], the Warrant Price in full for
Warrants exercised to [insert of name of Warrant Agent] [corporate trust
department] [insert address of Warrant Agent], Attention: ______________________
[or ________________], which [payment] [wire transfer] must specify the name of
the Holder and the number of Warrants exercised by such Holder. In addition, the
Holder must complete the information required below and present this Warrant
Certificate in person or by mail (certified or registered mail is recommended)
to the Warrant Agent at the appropriate address set forth below. This Warrant
Certificate, completed and duly executed, must be received by the Warrant Agent
within five business days of the [payment] [wire transfer].

                   To be Executed Upon Exercise of Warrant

            The undersigned hereby irrevocably elects to exercise __________
Warrants, evidenced by this Warrant Certificate, to purchase ________ shares of
the [Title of Warrant Securities] (the "Warrant Securities") of the Company and
represents that he has tendered payment for such Warrant Securities [in United
States dollars] [in applicable currency] [in cash] [by certified check or
official bank check or by bank wire transfer, in each case] [by bank wire
transfer] [in immediately available funds] to the order of Credit Suisse First
Boston (USA), Inc., c/o [insert name and address of Warrant Agent], in the
amount of ___________ in accordance with the terms hereof. The undersigned
requests that said principal amount of Warrant Securities be in fully registered
form in the authorized denominations, registered in such names and delivered all
as specified in accordance with the instructions set forth below.

            [If the number of Warrants exercised is less than all of the
Warrants evidenced hereby, the undersigned requests that a new Warrant
Certificate representing the remaining Warrants evidenced hereby be issued and
delivered to the undersigned unless otherwise specified in the instructions
below.]

                                      A-4
<Page>


Date: ___________________                Name:_________________
                                         Address_______________
_________________________                ______________________
(Insert Social Security or Other
Identifying Number of Holder)


Signature Guaranteed                     Signature

--------------------------               ---------------------------------------
                                         (Signature must conform in all respects
                                         to name of holder as specified on the
                                         face of this Warrant Certificate and
                                         must bear a signature guarantee by a
                                         bank, trust company or member broker of
                                         the New York, Midwest or Pacific Stock
                                         Exchange)

            The Warrants evidenced hereby may be exercised at the following
addresses:

By hand at
          ----------------------------------------------------------------------

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

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

By mail at
          ----------------------------------------------------------------------

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

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

            [Instructions as to form and delivery of Warrant Securities and, if
applicable, Warrant Certificates evidencing unexercised Warrants - complete as
appropriate.]

                                      A-5