Document:

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                                                                    EXHIBIT 4(c)

                          FIRST SUPPLEMENTAL INDENTURE

                                     between

                        FLEETBOSTON FINANCIAL CORPORATION

                                       and

                              THE BANK OF NEW YORK

                            Dated as of June 30, 2000

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                               Table of Contents*

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                                                    ARTICLE I
                                                   DEFINITIONS

SECTION 1.1   Definition of Terms.......................................................................2

                                                   ARTICLE II
                                  GENERAL TERMS AND CONDITIONS OF THE DEBENTURES

SECTION 2.1   Designation and Principal Amount..........................................................4
SECTION 2.2   Maturity..................................................................................4
SECTION 2.3   Form and Payment..........................................................................4
SECTION 2.4   Global Debenture..........................................................................4
SECTION 2.5   Interest..................................................................................5
SECTION 2.6   Denomination..............................................................................6

                                                  ARTICLE III
                                          REDEMPTION OF THE DEBENTURES

SECTION 3.1   Optional Redemption.......................................................................6
SECTION 3.2   Redemption Procedures.....................................................................7
SECTION 3.3   No Sinking Fund...........................................................................7
SECTION 3.4   Required Approval.........................................................................7

                                                  ARTICLE IV
                                   EXTENSION OF INTEREST PAYMENT PERIOD

SECTION 4.1   Extension of Interest Payment Period......................................................7
SECTION 4.2   Notice of Extension.......................................................................8
SECTION 4.3   Limitation of Transactions................................................................8

                                                  ARTICLE V
                                                  EXPENSES

SECTION 5.1   Payment of Expenses.......................................................................9
SECTION 5.2   Payment Upon Resignation or Removal......................................................10

                                                ARTICLE VI
                                       COVENANT TO LIST ON EXCHANGE

SECTION 6.1   Listing on an Exchange...................................................................10
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                                                ARTICLE VII
                                             FORM OF DEBENTURE

SECTION 7.1   Form of Debenture........................................................................10

                                               ARTICLE VIII
                                      ORIGINAL ISSUE OF DEBENTURES

SECTION 8.1   Original Issue of Debentures.............................................................16

                                                ARTICLE IX
                                              MISCELLANEOUS

SECTION 9.1   Ratification of Indenture................................................................16
SECTION 9.2   Trustee Not Responsible for Recitals.....................................................16
SECTION 9.3   Governing Law............................................................................16
SECTION 9.4   Separability.............................................................................17
SECTION 9.5   Counterparts.............................................................................17

* THIS TABLE OF CONTENTS SHALL NOT, FOR ANY PURPOSE, BE DEEMED TO BE A PART OF
  THIS FIRST SUPPLEMENTAL INDENTURE.
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     FIRST SUPPLEMENTAL INDENTURE, dated as of June 30, 2000 (the "First
Supplemental Indenture"), between FleetBoston Financial Corporation, a Rhode
Island corporation (the "Company"), and The Bank of New York, a New York banking
corporation, as trustee (the "Trustee") under the Indenture dated as of June 30,
2000 between the Company and the Trustee (the "Indenture").

     WHEREAS, the Company executed and delivered the Indenture to the Trustee to
provide for the future issuance of the Company's unsecured junior subordinated
debt securities to be issued from time to time in one or more series as might be
determined by the Company under the Indenture, in an unlimited aggregate
principal amount which may be authenticated and delivered as provided in the
Indenture;

     WHEREAS, pursuant to the terms of the Indenture, the Company desires to
provide for the establishment of a new series of such securities to be known as
its 8.80% Junior Subordinated Deferrable Interest Debentures due 2030 (the
"Debentures"), the form and substance of such Debentures and the terms,
provisions and conditions thereof to be set forth as provided in the Indenture
and this First Supplemental Indenture;

     WHEREAS, the Company and Fleet Capital Trust VI, a Delaware statutory
business trust (the "Trust"), has offered to the public up to $316,250,000
aggregate liquidation amount of its 8.80% Trust Originated Preferred
Securities(SM) ("TOPrS(SM)") (the "Preferred Securities"), representing
preferred undivided beneficial interests in the assets of the Trust, and
proposes to invest the proceeds from such offering, together with the proceeds
of the issuance and sale by the Trust to the Company of up to $9,781,000
aggregate liquidation amount of its 8.80% Common Securities (the "Common
Securities"), in up to $326,031,000 aggregate principal amount of the
Debentures; and

     WHEREAS, the Company has requested that the Trustee execute and deliver
this First Supplemental Indenture and all requirements necessary to make this
First Supplemental Indenture a valid instrument in accordance with its terms,
and to make the Debentures, when executed by the Company and authenticated and
delivered by the Trustee, the valid obligations of the Company, have been
performed, and the execution and delivery of this First Supplemental Indenture
has been duly authorized in all respects.

     NOW THEREFORE, in consideration of the purchase and acceptance of the
Debentures by the Holders thereof, and for the purpose of setting forth, as
provided in the Indenture, the form and substance of the Debentures and the
terms, provisions and conditions thereof, the Company covenants and agrees with
the Trustee as follows:

----------------------
     SM "Trust Originated Preferred Securities and "TOPrS" are service marks of
Merrill Lynch & Co., Inc.

                                       1

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                                    ARTICLE I
                                   DEFINITIONS

     SECTION 1.1 Definition of Terms.

     Unless the context otherwise requires:

     (a) a term defined in the Indenture has the same meaning when used in this
First Supplemental Indenture;

     (b) a term defined anywhere in this First Supplemental Indenture has the
same meaning throughout;

     (c) the singular includes the plural and vice versa;

     (d) a reference to a Section or Article is to a Section or Article of this
First Supplemental Indenture;

     (e) headings are for convenience of reference only and do not affect
interpretation;

     (f) the following terms have the meanings given to them in the Declaration:
(i) Purchase Agreement; (ii) Delaware Trustee; (iii) Distributions; (iv)
Institutional Trustee; (v) Preferred Securities Guarantee; (vi) Preferred
Security Certificate; and (vii) Regular Trustee; and

     (g) the following terms have the meanings given to them in this Section
1.1(g):

     "Additional Interest" shall have the meaning set forth in Section 2.5(c).

     "Compound Interest" shall have the meaning set forth in Section 4.1.

     "Coupon Rate" shall have the meaning set forth in Section 2.5(a).

     "Creditor" shall have the meaning set forth in Section 5.1.

     "Declaration" means the Amended and Restated Declaration of Trust of Fleet
Capital Trust VI, a Delaware statutory business trust, dated as of June 30,
2000.

     "Deferred Interest" shall have the meaning set forth in Section 4.1.

     "Dissolution Event" means the dissolution of the Trust and distribution of
the Debentures held by the Institutional Trustee pro rata to the holders of the
Trust Securities in accordance with the Declaration, such event to occur at the
option of the Company at any time.

     "Extended Interest Payment Period" shall have the meaning set forth in
Section 4.1.

     "Federal Reserve Board" means the Board of Governors of the Federal Reserve
System.

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     "Global Debenture" shall have the meaning set forth in Section 2.4(a).

     "Holder" means any person in whose name at the time a Debenture is
registered on the Security Register.

     "Interest Payment Date" shall have the meaning set forth in Section 2.5(a).

     "Non Book-Entry Preferred Securities" shall have the meaning set forth in
Section 2.4(a).

     "Prepayment Price" shall have the meaning set forth in Section 3.1.

     "Regulatory Capital Event" means that the Company shall have received an
opinion of independent bank regulatory counsel experienced in such matters to
the effect that, as a result of (a) any amendment to, or change (including any
announced prospective change) in, the laws (or any regulations thereunder) of
the United States or any rules, guidelines or policies of the Federal Reserve
Board or (b) any official administrative pronouncement or judicial decision
interpreting or applying such laws or regulations, which amendment or change is
effective or such pronouncement or decision is announced on or after the date of
original issuance of the Preferred Securities, the Preferred Securities do not
constitute, or within 90 days of the date thereof, will not constitute, Tier 1
capital (or its equivalent) for purposes of the Federal Reserve Board's capital
guidelines for bank holding companies; provided, however, that the distribution
of the Debentures in connection with the liquidation of the Trust by the Company
and the treatment thereafter of the Debentures as other than Tier 1 capital
shall not in and of itself constitute a Regulatory Capital Event unless such
liquidation shall have occurred in connection with a Tax Event.

     "Special Event" means a Tax Event or a Regulatory Capital Event, as the
case may be.

     "Stated Maturity" means the date on which the Debentures mature and on
which the principal shall be due and payable, together with all accrued and
unpaid interest thereon including Compound Interest and Additional Interest, if
any, which date shall be June 30, 2030.

     "Tax Event" means that the Regular Trustees shall have received an opinion
of a nationally recognized independent tax counsel experienced in such matters
to the effect that, as a result of (a) any amendment to, or change (including
any announced prospective change) in, the laws or any regulations thereunder of
the United States or any political subdivision or taxing authority thereof or
therein, or (b) any official administrative pronouncement or judicial decision
interpreting or applying such laws or regulations, which amendment or change is
effective or such pronouncement or decision is announced on or after the date of
the original issuance of the Debentures, there is more than an insubstantial
risk that (i) the Trust is, or will be within 90 days of the date of such
opinion, subject to United States federal income tax with respect to income
received or accrued on the Debentures, (ii) interest payable by the Company on
the Debentures is not, or within 90 days of the date thereof will not be,
deductible by the Company, in whole or in part, for United States federal income
tax purposes, or (iii) the Trust is, or will be within 90 days of the date of
such opinion, subject to more than a de minimis amount of other taxes, duties or
other governmental charges.

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                                   ARTICLE II
                 GENERAL TERMS AND CONDITIONS OF THE DEBENTURES

     SECTION 2.1 Designation and Principal Amount.

     There is hereby authorized a series of Securities designated as the "8.80%
Junior Subordinated Deferrable Interest Debentures due 2030", in aggregate
principal amount of up to $326,031,000 which amount shall be as set forth in any
written order of the Company for the authentication and delivery of Debentures
pursuant to Section 2.04 of the Indenture.

     SECTION 2.2 Maturity.

     The Debentures shall mature on June 30, 2030 (the "Stated Maturity").

     SECTION 2.3 Form and Payment.

     Except as provided in Section 2.4, the Debentures shall be issued in fully
registered certificated form without interest coupons. Principal and interest on
the Debentures issued in certificated form will be payable, the transfer of such
Debentures will be registrable and such Debentures will be exchangeable for
Debentures bearing identical terms and provisions at the office or agency of the
Trustee in New York, New York; provided, however, that payment of interest may
be made at the option of the Company by check mailed to the Holder entitled
thereto at such address as shall appear in the Security Register or by wire
transfer to an account appropriately designated by the Holder, entitled thereto.
Notwithstanding the foregoing, so long as the Holder of any Debentures is the
Institutional Trustee, the payment of the principal of and interest (including
Compound Interest and Additional Interest, if any) on such Debentures held by
the Institutional Trustee will be made at such place and to such account as may
be designated by the Institutional Trustee.

     SECTION 2.4 Global Debenture.

     (a) In connection with a Dissolution Event,

          (i) the Debentures in certificated form may be presented to the
     Trustee by the Institutional Trustee in exchange for a global Debenture in
     an aggregate principal amount equal to the aggregate principal amount of
     all outstanding Debentures (a "Global Debenture"), to be registered in the
     name of the Depository Institution, or its nominee, and delivered by the
     Trustee to the Depository Institution for crediting to the accounts of its
     participants pursuant to the instructions of the Regular Trustees. The
     Company upon any such presentation shall execute a Global Debenture in such
     aggregate principal amount and deliver the same to the Trustee for
     authentication and delivery in accordance with the Indenture and this First
     Supplemental Indenture. Payments on the Debentures issued as a Global
     Debenture will be made to the Depository Institution; and

          (ii) if any Preferred Securities are held in non book-entry
     certificated form, the Debentures in certificated form may be presented to
     the Trustee by the Institutional Trustee and any Preferred Security
     Certificate which represents Preferred Securities other than Preferred
     Securities held by the Depository Institution or its nominee ("Non
     Book-

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     Entry Preferred Securities") will be deemed to represent beneficial
     interests in Debentures presented to the Trustee by the Institutional
     Trustee having an aggregate principal amount equal to the aggregate
     liquidation amount of the Non Book-Entry Preferred Securities until such
     Preferred Security Certificates are presented to the Security registrar for
     transfer or reissuance, at which time such Preferred Security Certificates
     will be canceled and a Debenture, registered in the name of the holder of
     the Preferred Security Certificate or the transferee of the holder of such
     Preferred Security Certificate, as the case may be, with an aggregate
     principal amount equal to the aggregate liquidation amount of the Preferred
     Security Certificate canceled, will be executed by the Company and
     delivered to the Trustee for authentication and delivery in accordance with
     the Indenture and this First Supplemental Indenture. On issue of such
     Debentures, Debentures with an equivalent aggregate principal amount that
     were presented by the Institutional Trustee to the Trustee will be deemed
     to have been canceled.

          (b) A Global Debenture may be transferred, in whole but not in part,
     only to another nominee of the Depository Institution, or to a successor
     Depository Institution selected or approved by the Company or to a nominee
     of such successor Depository Institution.

          (c) If (i) at any time the Depository Institution notifies the Company
     that it is unwilling or unable to continue as Depository Institution or if
     at any time the Depository Institution for such series shall no longer be
     registered or in good standing under the Securities Exchange Act of 1934,
     as amended, or other applicable statute or regulation, and a successor
     Depository Institution for such series is not appointed by the Company
     within 90 days after the Company receives such notice or becomes aware of
     such condition, as the case may be, (ii) the Company at any time determines
     that the Debentures shall no longer be solely represented by a Global
     Debenture or (iii) there shall have occurred an Event of Default, then the
     Company shall execute, and, subject to Article II of the Indenture, the
     Trustee, upon written notice from the Company, shall authenticate and
     deliver the Debentures in definitive registered form without coupons, in
     authorized denominations, and in an aggregate principal amount equal to the
     principal amount of the Global Debenture in exchange for such Global
     Debenture. In such event the Company shall execute, and, subject to Section
     2.07 of the Indenture, the Trustee, upon receipt of an Officers'
     Certificate evidencing such determination by the Company, shall
     authenticate and deliver the Debentures in definitive registered form
     without coupons, in authorized denominations, and in an aggregate principal
     amount equal to the principal amount of the Global Debenture in exchange
     for such Global Debenture. Upon the exchange of the Global Debenture for
     such Debentures in definitive registered form without coupons, in
     authorized denominations, the Global Debenture shall be canceled by the
     Trustee. Such Debentures in definitive registered form issued in exchange
     for the Global Debenture shall be registered in such names and in such
     authorized denominations as the Depository Institution, pursuant to
     instructions from its direct or indirect participants or otherwise, shall
     instruct the Trustee. The Trustee shall deliver such Securities to the
     Depository Institution for delivery to the Persons in whose names such
     Securities are so registered.

          SECTION 2.5 Interest.

     (a) Each Debenture will bear interest at the rate of 8.80% per annum (the
"Coupon Rate") from June 30, 2000 until the principal thereof becomes due and
payable, and on any

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overdue principal and, to the extent that payment of such interest is
enforceable under applicable law, on any overdue installment of interest at the
Coupon Rate, compounded quarterly, payable quarterly in arrears on March 31,
June 30, September 30 and December 31 of each year (each, an "Interest Payment
Date"), commencing on September 30, 2000, to the Person in whose name such
Debenture or any predecessor Debenture is registered at the close of business on
the relevant record date, which will be, as long as the Preferred Securities
remain in book-entry form (or if no Preferred Securities remain outstanding, as
long as the Debentures remain in book entry form), one Business Day prior to the
relevant Interest Payment Date and, in the event the Preferred Securities are
not in book-entry form (or if no Preferred Securities remain outstanding, in the
event the Debentures are not in book entry form), the 15th day of the month in
which the relevant Interest Payment Date date occurs, except as otherwise
provided pursuant to the provisions of Article IV hereof.

     (b) The amount of interest payable for any period will be computed on the
basis of a 360-day year of twelve 30-day months. Except as provided in the
following sentence, the amount of interest payable for any period shorter than a
full quarterly period for which interest is computed, will be computed on the
basis of the actual number of days elapsed per calendar month (but not to exceed
30 days in any month). In the event that any date on which interest is payable
on the Debentures is not a Business Day, then payment of interest payable on
such date will be made on the next succeeding day which is a Business Day (and
without any interest or other payment in respect of any such delay), except
that, if such Business Day is in the next succeeding calendar year, such payment
shall be made on the immediately preceding Business Day, in each case with the
same force and effect as if made on the date that such interest otherwise would
have been payable.

     (c) If, at any time while the Institutional Trustee is the holder of any
Junior Subordinated Debentures, the Trust or the Institutional Trustee is
required to pay any taxes, duties, assessments or governmental charges of
whatever nature (other than withholding taxes) imposed by the United States, or
any other taxing authority, then, in any such case, the Company will pay as
additional interest ("Additional Interest") on the Debentures held by the
Institutional Trustee, such additional amounts as shall be required so that the
net amounts received and retained by the Trust and by the Institutional Trustee
after paying such taxes, duties, assessments or other governmental charges will
be equal to the amounts the Trust and the Institutional Trustee would have
received had no such taxes, duties, assessments or other governmental charges
been imposed.

     SECTION 2.6 Denomination.

     The Debentures shall be issued in denominations of $25 and integral
multiples thereof.

                                  ARTICLE III
                          REDEMPTION OF THE DEBENTURES

     SECTION 3.1 Optional Redemption.

     The Junior Subordinated Debentures are prepayable prior to the Stated
Maturity at the option of the Company (i) in whole or in part, from time to
time, on or after June 30, 2005

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or (ii) at any time prior to June 30, 2005, in whole but not in part, upon the
occurrence and continuation of a Special Event, in either case at a prepayment
price (the "Prepayment Price") equal to 100% of the principal amount thereof,
plus accrued and unpaid interest thereon (including Additional Interest and
Compound Interest, if any) to the date of prepayment.

     SECTION 3.2 Redemption Procedures.

     Notice of any redemption will be mailed at least 30 days but not more than
60 days before the redemption date to each Holder of Debentures to be prepaid at
its registered address. Unless the Company defaults in payment of the prepayment
price, on and after the redemption date interest shall cease to accrue on such
Debentures called for redemption. If the Debentures are only partially redeemed
pursuant to Section 3.1, the Debentures will be redeemed pro rata or by lot or
by any other method utilized by the Trustee; provided, that if at the time of
redemption the Debentures are registered as a Global Debenture, the Depository
Institution shall determine, in accordance with its procedures, the principal
amount of such Debentures held by each Depository Institution participant to be
redeemed. The Prepayment Price shall be paid prior to 12:00 noon, New York time,
on the date of such prepayment or at such earlier time as the Company
determines; provided that the Company shall deposit with the Trustee an amount
sufficient to pay the Prepayment Price by 10:00 a.m., New York time, on the date
such prepayment price is to be paid.

     SECTION 3.3 No Sinking Fund.

     The Debentures are not entitled to the benefit of any sinking fund.

     SECTION 3.4 Required Approval.

     Any redemption of the Debentures in accordance with the foregoing Sections
may require the prior approval of the Federal Reserve Board if such approval is
then required under applicable law, rules, guidelines or policies.

                                   ARTICLE IV
                      EXTENSION OF INTEREST PAYMENT PERIOD

     SECTION 4.1 Extension of Interest Payment Period.

     So long as the Company shall not be in default in the payment of interest
on the Debentures, the Company shall have the right, at any time and from time
to time during the term of the Debentures, to defer payments of interest by
extending the interest payment period of such Debentures for a period not
exceeding 20 consecutive quarters (the "Extended Interest Payment Period"),
during which Extended Interest Payment Period no interest shall be due and
payable; provided that no Extended Interest Payment Period may extend beyond the
Stated Maturity. To the extent permitted by applicable law, interest, the
payment of which has been deferred because of the extension of the interest
payment period pursuant to this Section 4.1, will bear interest thereon at the
Coupon Rate compounded quarterly for each quarter of the Extended Interest
Payment Period ("Compound Interest"). At the end of the Extended Interest
Payment Period, the Company shall pay all interest accrued and unpaid on the
Debentures, including any Additional Interest and Compound Interest (together,
"Deferred Interest") that shall be payable to the

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Holders in whose names the Debentures are registered in the Security Register on
the record date for the first Interest Payment Date after the end of the
Extended Interest Payment Period. Before the termination of any Extended
Interest Payment Period, the Company may further extend such period, provided
that such period together with all such further extensions thereof shall not
exceed 20 consecutive quarters, or extend beyond the Stated Maturity of the
Debentures. Upon the termination of any Extended Interest Payment Period and
upon the payment of all Deferred Interest then due, the Company may commence a
new Extended Interest Payment Period, subject to the foregoing requirements. No
interest shall be due and payable during an Extended Interest Payment Period,
except at the end thereof, but the Company may prepay at any time all or any
portion of the interest accrued during an Extended Interest Payment Period.

     SECTION 4.2 Notice of Extension.

     (a) If the Institutional Trustee is the only registered Holder at the time
the Company selects an Extended Interest Payment Period, the Company shall give
written notice to the Regular Trustees, the Institutional Trustee and the
Trustee of its selection of such Extended Interest Payment Period one Business
Day before the earlier of (i) the next succeeding date on which Distributions on
the Trust Securities issued by the Trust are payable, or (ii) the date the Trust
is required to give notice of the record date, or the date such Distributions
are payable, to the New York Stock Exchange or other applicable self-regulatory
organization or to holders of the Preferred Securities issued by the Trust, but
in any event at least one Business Day before such record date.

     (b) If the Institutional Trustee is not the only Holder at the time the
Company selects an Extended Interest Payment Period, the Company shall give the
Holders of the Debentures and the Trustee written notice of its selection of
such Extended Interest Payment Period at least ten Business Days before the
earlier of (i) the next succeeding Interest Payment Date, or (ii) the date the
Company is required to give notice of the record date or the Interest Payment
Date to the New York Stock Exchange or other applicable self-regulatory
organization or to Holders of the Debentures.

     (c) The quarter in which any notice is given pursuant to paragraphs (a) or
(b) of this Section 4.2 shall be counted as one of the 20 quarters permitted in
the maximum Extended Interest Payment Period permitted under Section 4.1.

     SECTION 4.3 Limitation of Transactions.

     If (i) the Company shall exercise its right to defer payment of interest as
provided in Section 4.1 and the Extended Interest Payment Period is continuing,
or (ii) there shall have occurred any Event of Default, as defined in the
Indenture, or (iii) there shall have occurred any Event of Default, as defined
in the Preferred Securities Guarantee, then (a) the Company shall not declare or
pay any dividend on, make any distribution with respect to, or redeem, purchase,
acquire or make a liquidation payment with respect to, any of its capital stock
(other than (1) purchases or acquisitions of shares of its common stock in
connection with the satisfaction by the Company of its obligations under any
employee benefit plans or any other contractual obligation of the Company (other
than a contractual obligation ranking pari passu with or junior to the
Debentures), (2) as a result of a reclassification of the Company's capital
stock or the

                                       8

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exchange or conversion of one class or series of the Company's capital stock for
another class or series of the Company's capital stock or (3) the purchase of
fractional interests in shares of the Company's capital stock pursuant to the
conversion or exchange provisions of such capital stock or the security being
converted or exchanged), (b) the Company shall not make any payment of interest,
principal or premium, if any, on or repay, repurchase or redeem any debt
securities issued by the Company that rank pari passu with or junior to the
Debentures and (c) the Company shall not make any guarantee payments with
respect to the foregoing (other than pursuant to the Preferred Securities
Guarantee).

                                   ARTICLE V
                                    EXPENSES

     SECTION 5.1 Payment of Expenses.

     In connection with the offering, sale and issuance of the Debentures to the
Institutional Trustee and in connection with the sale of the Trust Securities by
the Trust, the Company, in its capacity as borrower with respect to the
Debentures, shall:

     (a) pay all costs and expenses relating to the offering, sale and issuance
of the Debentures, including commissions to the underwriter payable pursuant to
the Purchase Agreement and compensation of the Trustee under the Indenture in
accordance with the provisions of Section 6.06 of the Indenture;

     (b) be responsible for and shall pay all debts and obligations (other than
with respect to the Trust Securities) and all costs and expenses of the Trust
(including, but not limited to, costs and expenses relating to the organization,
maintenance and dissolution of the Trust, the offering, sale and issuance of the
Trust Securities (including commissions to the underwriters in connection
therewith), the fees and expenses (including reasonable counsel fees and
expenses) of the Institutional Trustee, the Delaware Trustee and the Regular
Trustees (including any amounts payable under Article 10 of the Declaration),
the costs and expenses relating to the operation of the Trust, including without
limitation, costs and expenses of accountants, attorneys, statistical or
bookkeeping services, expenses for printing and engraving and computing or
accounting equipment, paying agent(s), registrar(s), transfer agent(s),
duplicating, travel and telephone and other telecommunications expenses and
costs and expenses incurred in connection with the acquisition, financing, and
disposition of Trust assets and the enforcement by the Institutional Trustee of
the rights of the holders of the Preferred Securities);

     (c) be liable for any indemnification obligations arising with respect to
the Declaration; and

     (d) pay any and all taxes (other than United States withholding taxes
attributable to the Trust or its assets) and all liabilities, costs and expenses
with respect to such taxes of the Trust.

     The Company's obligations under this Section 5.1 shall be for the benefit
of, and shall be enforceable by, any Person to whom such debts, obligations,
costs, expenses and taxes are owed (a "Creditor") whether or not such Creditor
has received notice hereof. Any such Creditor may enforce the Company's
obligations under this Section 5.1 directly against the Company and the

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Company irrevocably waives any right of remedy to require that any such Creditor
take any action against the Trust or any other Person before proceeding against
the Company. The Company agrees to execute such additional agreements as may be
necessary or desirable in order to give full effect to the provisions of this
Section 5.1.

     The provisions of this Section shall survive the termination of this
Supplemental Indenture.

     SECTION 5.2 Payment Upon Resignation or Removal.

     Upon termination of this First Supplemental Indenture or the Indenture or
the removal or resignation of the Trustee, unless otherwise stated, the Company
shall pay to the Trustee all amounts accrued to the date of such termination,
removal or resignation that are payable pursuant to Section 6.06 of the
Indenture. Upon termination of the Declaration or the removal or resignation of
the Delaware Trustee or the Institutional Trustee, as the case may be, pursuant
to Section 5.6 of the Declaration, the Company shall pay to the Delaware Trustee
or the Institutional Trustee, as the case may be, all amounts accrued to the
date of such termination, removal or resignation.

                                   ARTICLE VI
                          COVENANT TO LIST ON EXCHANGE

     SECTION 6.1 Listing on an Exchange.

     If the Debentures are distributed to the holders of the Securities issued
by the Trust, and the Preferred Securities are then so listed, the Company will
use its best efforts to list such Debentures on the New York Stock Exchange,
Inc. or on such other exchange as the Preferred Securities are then listed.

                                  ARTICLE VII
                                FORM OF DEBENTURE

     SECTION 7.1 Form of Debenture.

     The Debentures and the Trustee's Certificate of Authentication to be
endorsed thereon are to be substantially in the following forms:

                           (FORM OF FACE OF DEBENTURE)

     IF THE DEBENTURE IS TO BE A GLOBAL DEBENTURE, INSERT - This Debenture is a
Global Debenture within the meaning of the Indenture hereinafter referred to and
is registered in the name of a Depositary or a nominee of a Depositary. This
Debenture is exchangeable for Debentures registered in the name of a person
other than the Depositary or its nominee only in the limited circumstances
described in the Indenture, and no transfer of this Debenture (other than a
transfer of this Debenture as a whole by the Depositary to a nominee of the
Depositary or by a nominee of the Depositary to the Depositary or another
nominee of the Depositary) may be registered except in limited circumstances.

                                       10

<PAGE>   14

     Unless this Debenture is presented by an authorized representative of The
Depository Trust Company (55 Water Street, New York, New York) to the issuer or
its agent for registration of transfer, exchange or payment, and any Debenture
issued is registered in the name of Cede & Co. or such other name as requested
by an authorized representative of The Depository Trust Company and any payment
hereon is made to Cede & Co., ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE
OR OTHERWISE BY A PERSON IS WRONGFUL since the registered owner hereof, Cede &
Co., has an interest herein.

                                      No. 1
                        FLEETBOSTON FINANCIAL CORPORATION
             8.80% JUNIOR SUBORDINATED DEFERRABLE INTEREST DEBENTURE
                                    DUE 2030
$                                                               CUSIP#__________

     FLEETBOSTON FINANCIAL CORPORATION, a Rhode Island corporation (the
"Company", which term includes any successor corporation under the Indenture
hereinafter referred to), for value received, hereby promises to pay to The Bank
of New York, as Institutional Trustee of Fleet Capital Trust VI under that
certain Amended and Restated Declaration of Trust dated as of June 30, 2000, or
registered assigns, the principal sum of [ ] ($__________) on June 30, 2030,
(the "Stated Maturity"), and to pay interest on said principal sum from June 30,
2000, or from the most recent interest payment date (each such date, an
"Interest Payment Date") to which interest has been paid or duly provided for,
quarterly (subject to deferral as set forth herein) in arrears on March 31, June
30, September 30 and December 31 of each year commencing September 30, 2000, at
the rate of 8.80% per annum (the "Coupon Rate") until the principal hereof shall
have become due and payable, and on any overdue principal and premium, and
(without duplication and to the extent that payment of such interest is
enforceable under applicable law) on any overdue installment of interest at the
same rate per annum compounded quarterly. The amount of interest payable on any
Interest Payment Date shall be computed on the basis of a 360-day year of twelve
30-day months and, except as provided in the following sentences, the amount of
interest payable for any period shorter than a full quarterly period for which
interest is computed, will be computed on the basis of the actual number of days
elapsed per calendar month (but not to exceed 30 days in any month). In the
event that any date on which interest is payable on this Debenture is not a
Business Day, then payment of interest payable on such date will be made on the
next succeeding day that is a Business Day (and without any interest or other
payment in respect of any such delay), except that, if such Business Day is in
the next succeeding calendar year, such payment shall be made on the immediately
preceding Business Day, in each case with the same force and effect as if made
on the date such payment otherwise would have been payable. The interest
installment so payable, and punctually paid or duly provided for, on any
Interest Payment Date will, as provided in the Indenture, be paid to the person
in whose name this Debenture (or one or more Predecessor Securities, as defined
in said Indenture) is registered at the close of business on the relevant record
dates, which will be, as long as this Debenture remains in book-entry form, one
Business Day prior to the relevant Interest Payment Date and, in the event this
Debenture is not in book-entry form, the 15th day of the month in which the
relevant Interest Payment Date occurs. Payments of interest may be deferred by
the Company pursuant to the provisions of Article IV of the First Supplemental
Indenture to the Indenture (as defined herein). Any such interest installment
not punctually paid or duly provided for shall forthwith cease to be payable

                                       11

<PAGE>   15

to the registered Holders on such regular record date and may be paid to the
Person in whose name this Debenture (or one or more Predecessor Securities) is
registered at the close of business on a special record date to be fixed by the
Trustee for the payment of such defaulted interest, notice whereof shall be
given to the registered Holders of this series of Debentures not less than 10
days prior to such special record date, or may be paid at any time in any other
lawful manner not inconsistent with the requirements of any securities exchange
on which the Debentures may be listed, and upon such notice as may be required
by such exchange, all as more fully provided in the Indenture. The principal of
(and premium, if any) and the interest on this Debenture shall be payable at the
office or agency of the Trustee maintained for that purpose in any coin or
currency of the United States of America that at the time of payment is legal
tender for payment of public and private debts; provided, however, that payment
of interest may be made at the option of the Company by check mailed to the
registered Holder at such address as shall appear in the Security Register.
Notwithstanding the foregoing, so long as the Holder of this Debenture is the
Institutional Trustee, the payment of the principal of (and premium, if any) and
interest on this Debenture will be made at such place and to such account as may
be designated by the Institutional Trustee.

     The indebtedness evidenced by this Debenture is, to the extent provided in
the Indenture, subordinate and junior in right of payment to the prior payment
in full of all Senior Indebtedness and Other Financial Obligations (each as
defined in the Indenture) and this Debenture is issued subject to the provisions
of the Indenture with respect thereto. Each Holder of this Debenture, by
accepting the same, (a) agrees to and shall be bound by such provisions, (b)
authorizes and directs the Trustee on his or her behalf to take such action as
may be necessary or appropriate to acknowledge or effectuate the subordination
so provided and (c) appoints the Trustee his or her attorney-in-fact for any and
all such purposes. Each Holder hereof, by his or her acceptance hereof, hereby
waives all notice of the acceptance of the subordination provisions contained
herein and in the Indenture by each holder of Senior Indebtedness and Other
Financial Obligations, whether now outstanding or hereafter incurred, and waives
reliance by each such holder upon said provisions.

     This Debenture shall not be entitled to any benefit under the Indenture
hereinafter referred to, be valid or become obligatory for any purpose until the
Certificate of Authentication hereon shall have been signed by or on behalf of
the Trustee.

     THIS DEBENTURE IS NOT A SAVINGS OR DEPOSIT ACCOUNT OR OTHER OBLIGATION OF A
BANK AND IS NOT INSURED BY THE FEDERAL DEPOSIT INSURANCE CORPORATION OR ANY
OTHER GOVERNMENTAL AGENCY.

     The provisions of this Debenture are continued on the reverse side hereof
and such continued provisions shall for all purposes have the same effect as
though fully set forth at this place.

                                       12

<PAGE>   16

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

                                     FLEETBOSTON FINANCIAL CORPORATION

                                     By:____________________________________
                                     Name:
                                     Title:
Attest:

By:______________________________________
Name:
Title:

                     (FORM OF CERTIFICATE OF AUTHENTICATION)
                          CERTIFICATE OF AUTHENTICATION

Dated: [    ]

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

The Bank of New York,
as Trustee

By:_______________________________________
             Authorized Signatory

                         (FORM OF REVERSE OF DEBENTURE)

     This Debenture is one of a duly authorized series of Debentures of the
Company (herein sometimes referred to as the "Debentures"), specified in the
Indenture, all issued or to be issued in one or more series under and pursuant
to an Indenture dated as of June 30, 2000, duly executed and delivered between
the Company and The Bank of New York, as trustee (the "Trustee"), as
supplemented by the First Supplemental Indenture dated as of June 30, 2000
between the Company and the Trustee (the Indenture as so supplemented, the
"Indenture"), to which Indenture and all indentures supplemental thereto
reference is hereby made for a description of the rights, limitations of rights,
obligations, duties and immunities thereunder of the Trustee, the Company and
the Holders of the Debentures. By the terms of the Indenture, the Debentures are
issuable in series that may vary as to amount, date of maturity, rate of
interest and in other respects as provided in the Indenture. This series of
Debentures is limited in aggregate principal amount as specified in said First
Supplemental Indenture.

                                     13

<PAGE>   17

     The Debenture is redeemable by the Company (i) in whole but not in part at
any time prior to June 30, 2005 upon the occurrence and continuation of a
Special Event (as defined in the Indenture) or (ii) in whole or in part on or
after June 30, 2005. Any redemption pursuant to this paragraph will be made upon
not less than 30 days nor more than 60 days notice, at a redemption price equal
to 100% of the principal amount plus any accrued but unpaid interest thereon
(including Additional Interest and Compound Interest, if any) to the date of
such redemption (the "Prepayment Price"). The Prepayment Price shall be paid
prior to 12:00 noon, New York time, on the date of such redemption or at such
earlier time as the Company determines. If the Debentures are only partially
redeemed by the Company pursuant to an Optional Redemption, the Debentures will
be redeemed pro rata or by lot or by any other method utilized by the Trustee
(in integral multiples of $25); provided that if, at the time of redemption, the
Debentures are registered as a Global Debenture, the Depositary shall determine
the principal amount of such Debentures held by each Debenture holder to be
redeemed in accordance with its procedures.

     In the event of redemption of this Debenture in part only, a new Debenture
or Debentures of this series for the unredeemed portion hereof will be issued in
the name of the Holder hereof upon the cancellation hereof.

     In case an Event of Default, as defined in the Indenture, shall have
occurred and be continuing, the principal of all of the Debentures may be
declared, and upon such declaration shall become, due and payable, in the
manner, with the effect and subject to the conditions provided in the Indenture.

     The Indenture contains provisions permitting the Company and the Trustee,
with the consent of the Holders of not less than a majority in aggregate
principal amount of the Debentures of each series affected at the time
outstanding, as defined in the Indenture, to execute supplemental indentures for
the purpose of adding any provisions to or changing in any manner or eliminating
any of the provisions of the Indenture or of any supplemental indenture or of
modifying in any manner the rights of the Holders of the Debentures; provided,
however, that no such supplemental indenture shall (i) extend the fixed maturity
of any Debentures of any series, or reduce the principal amount thereof or any
premium thereon, or reduce the rate or extend the time of payment of interest
thereon, or reduce any amount payable on redemption thereof or make the
principal thereon or any interest or premium thereon payable in any coin or
currency other than that provided in this Debenture, or impair or affect the
right of any Holder of a Debenture to institute suit for payment thereof or the
right of repayment, if any, at the option of the Holder, without the consent of
the Holder of each Debenture so affected, or (ii) reduce the aforesaid
percentage of Debentures, the Holders of which are required to consent to any
such supplemental indenture, without the consent of the Holders of each
Debenture then outstanding and affected thereby. The Indenture also contains
provisions permitting the Holders of a majority in aggregate principal amount of
the Debentures of any series at the time outstanding affected thereby, on behalf
of all of the Holders of the Debentures of such series, to waive any past
default in the performance of any of the covenants contained in the Indenture,
or established pursuant to the Indenture with respect to such series, and its
consequences, except a default in the payment of the principal of or premium, if
any, or interest on any of the Debentures of such series. Any such consent or
waiver by the registered Holder of this Debenture (unless revoked as provided in
the Indenture) shall be conclusive and binding upon such Holder and upon all
future Holders and owners of this Debenture and of any Debenture issued in
exchange hereof or in

                                       14

<PAGE>   18

place hereof (whether by registration of transfer or otherwise), irrespective of
whether or not any notation of such consent or waiver is made upon this
Debenture.

     No reference herein to the Indenture and no provision of this Debenture or
of the Indenture shall alter or impair the obligation of the Company, which is
absolute and unconditional, to pay the principal of and premium, if any, and
interest on this Debenture at the time and place and at the rate and in the
money herein prescribed.

     The Company shall have the right at any time during the term of the
Debentures and from time to time to extend the interest payment period of such
Debentures for up to 20 consecutive quarters (an "Extended Interest Payment
Period"), at the end of which period the Company shall pay all interest then
accrued and unpaid (together with interest thereon at the rate specified for the
Debentures to the extent that payment of such interest is enforceable under
applicable law); provided that no Extended Interest Payment Period may last
beyond the Stated Maturity of the Debentures. Before the termination of any such
Extended Interest Payment Period, the Company may further extend such Extended
Interest Payment Period, provided that such Extended Interest Payment Period
together with all such further extensions thereof shall not exceed 20
consecutive quarters or last beyond the Stated Maturity date of the Debentures.
At the termination of any such Extended Interest Payment Period and upon the
payment of all accrued and unpaid interest, including any Additional Interest
and Compound Interest, the Company may commence a new Extended Interest Payment
Period.

     As provided in the Indenture and subject to certain limitations therein set
forth, this Debenture is transferable by the registered Holder hereof on the
Security Register, upon surrender of this Debenture for registration of transfer
at the office or agency of the Trustee in the City and State of New York,
accompanied by a written instrument or instruments of transfer in form
satisfactory to the Company or the Trustee duly executed by the registered
Holder hereof or his attorney duly authorized in writing, and thereupon one or
more new Debentures of authorized denominations and for the same aggregate
principal amount and series will be issued to the designated transferee or
transferees. No service charge will be made for any such transfer, but the
Company may require payment of a sum sufficient to cover any tax or other
governmental charge payable in relation thereto.

     Prior to due presentment for registration of transfer of this Debenture,
the Company, the Trustee, any paying agent, any transfer agent and any security
registrar may deem and treat the registered holder hereof as the absolute owner
hereof (whether or not this Debenture shall be overdue and notwithstanding any
notice of ownership or writing hereon made by anyone other than a security
registrar) for the purpose of receiving payment of or on account of the
principal hereof and premium, if any, and interest due hereon and for all other
purposes, and none of the Company, the Trustee, any paying agent, any transfer
agent or any security registrar shall be affected by any notice to the contrary.

     No recourse shall be had for the payment of the principal of or the
interest on this Debenture, or for any claim based hereon, or otherwise in
respect hereof, or based on or in respect of the Indenture, against any
incorporator, stockholder, officer or director, past, present or future, as
such, of the Company or of any predecessor or successor corporation, whether by
virtue of any constitution, statute or rule of law, or by the enforcement of any
assessment or

                                       15

<PAGE>   19

penalty or otherwise, all such liability being, by the acceptance hereof and as
part of the consideration for the issuance hereof, expressly waived and
released.

     The Debentures of this series are issuable only in registered form without
coupons in denominations of $25 and any integral multiple thereof. As provided
in the Indenture and subject to certain limitations herein and therein set
forth, Debentures of this series so issued are exchangeable for a like aggregate
principal amount of Debentures of this series of a different authorized
denomination, as requested by the Holder surrendering the same.

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

     This Debenture shall be governed by the internal laws of the State of New
York, and for all purposes shall be construed in accordance with the laws of
said State.

                                  ARTICLE VIII
                          ORIGINAL ISSUE OF DEBENTURES

     SECTION 8.1 Original Issue of Debentures.

     Debentures in the aggregate principal amount of up to $326,031,000, may,
upon execution of this First Supplemental Indenture or upon any written order of
the Company setting forth the amount therefor, be executed by the Company and
delivered to the Trustee for authentication, and the Trustee shall thereupon
authenticate and deliver said Debentures to or upon the written order of the
Company, signed by its Chairman, its President, or any Vice President and its
Treasurer, its Secretary, any Assistant Treasurer, or any Assistant Secretary,
without any further action by the Company.

                                   ARTICLE IX
                                  MISCELLANEOUS

     SECTION 9.1 Ratification of Indenture.

     The Indenture, as supplemented by this First Supplemental Indenture, is in
all respects ratified and confirmed, and this First Supplemental Indenture shall
be deemed part of the Indenture in the manner and to the extent herein and
therein provided.

     SECTION 9.2 Trustee Not Responsible for Recitals.

     The recitals herein contained are made by the Company and not by the
Trustee, and the Trustee assumes no responsibility for the correctness thereof.
The Trustee makes no representation as to the validity or sufficiency of this
First Supplemental Indenture.

     SECTION 9.3 Governing Law.

     This First Supplemental Indenture and each Debenture shall be deemed to be
a contract made under the internal laws of the State of New York, and for all
purposes shall be construed in accordance with the laws of such State.

                                       16

<PAGE>   20

     SECTION 9.4 Separability.

     In case any one or more of the provisions contained in this First
Supplemental Indenture or in the Debentures shall for any reason be held to be
invalid, illegal or unenforceable in any respect, such invalidity, illegality or
unenforceability shall not affect any other provisions of this First
Supplemental Indenture or of the Debentures, but this First Supplemental
Indenture and the Debentures shall be construed as if such invalid or illegal or
unenforceable provision had never been contained herein or therein.

     SECTION 9.5 Counterparts.

     This First Supplemental Indenture may be executed in any number of
counterparts each of which shall be an original; but such counterparts shall
together constitute but one and the same instrument.

                                       17

<PAGE>   21

     IN WITNESS WHEREOF, the parties hereto have caused this First Supplemental
Indenture to be duly executed by their respective officers thereunto duly
authorized as of the day and year first above written.

[Seal]                                 FLEETBOSTON FINANCIAL CORPORATION

Attest:

By: /s/ JANICE B. LIVA                 By: /s/ DOUGLAS L. JACOBS
   -------------------------------         -----------------------------------
   Name: Janice B. Liva                    Name: Douglas L. Jacobs
   Title: Assistant Secretary              Title: Senior Vice President and
                                                  Treasurer

                                       THE BANK OF NEW YORK,
                                       as Trustee

                                       By: /s/ MICHAEL CULHANE
                                           -----------------------------------
                                           Name: Michael Culhane
                                           Title: Vice President

                                       18

<PAGE>   22

STATE OF MASSACHUSETTS  )
COUNTY OF SUFFOLK       )     ss.:

On the 29th day of June, 2000 before me personally came Douglas L. Jacobs, to me
known, who, being by me duly sworn, did depose and say that he resides in
Providence, Rhode Island; that he is Senior Vice President and Treasurer of
FleetBoston Financial Corporation, one of the corporations described in and
which executed the above instrument; that he knows the corporate seal of said
corporation; that the seal affixed to the said instrument is such corporate
seal; that it was so affixed by authority of the Board of Directors of said
corporation; and that he signed his name thereto by like authority.

/s/ PATRICK D. GANNON
----------------------------------
Notary Public

[seal] Commission expires: October 11, 2002

                                       19<PAGE>   1

                                                                    EXHIBIT 4(f)

                    PREFERRED SECURITIES GUARANTEE AGREEMENT

                             Fleet Capital Trust VI

                            Dated as of June 30, 2000

<PAGE>   2

                                Table of Contents

<TABLE>
<CAPTION>
                                                                                                        Page
                                                                                                        ----
<S>              <C>                                                                                   <C>

                                                     ARTICLE I
                                          DEFINITIONS AND INTERPRETATION

SECTION 1.1       Definitions and Interpretation.........................................................1

                                                    ARTICLE II
                                                TRUST INDENTURE ACT

SECTION 2.1       Trust Indenture Act; Application.......................................................4
SECTION 2.2       Lists of Holders of Securities.........................................................5
SECTION 2.3       Reports by the Preferred Guarantee Trustee.............................................5
SECTION 2.4       Periodic Reports to Preferred Guarantee Trustee........................................5
SECTION 2.5       Evidence of Compliance with Conditions Precedent.......................................5
SECTION 2.6       Events of Default; Waiver..............................................................6
SECTION 2.7       Event of Default; Notice...............................................................6
SECTION 2.8       Conflicting Interests..................................................................6

                                                   ARTICLE III
                              POWERS, DUTIES AND RIGHTS OF PREFERRED GUARANTEE TRUSTEE

SECTION 3.1       Powers and Duties of the Preferred Guarantee Trustee...................................6
SECTION 3.2       Certain Rights of Preferred Guarantee Trustee..........................................8
SECTION 3.3       Not Responsible for Recitals or Issuance of Preferred Securities Guarantee............10

                                                   ARTICLE IV
                                           PREFERRED GUARANTEE TRUSTEE

SECTION 4.1       Preferred Guarantee Trustee; Eligibility..............................................10
SECTION 4.2       Appointment, Removal and Resignation of Preferred Guarantee Trustee...................11

                                                    ARTICLE V
                                                    GUARANTEE

SECTION 5.1       Guarantee.............................................................................12
SECTION 5.2       Waiver of Notice and Demand...........................................................12
SECTION 5.3       Obligations Not Affected..............................................................12
SECTION 5.4       Enforcement of Guarantee; Rights of Holders...........................................13
SECTION 5.5       Guarantee of Payment..................................................................13
SECTION 5.6       Subrogation...........................................................................13
SECTION 5.7       Independent Obligations...............................................................14

</TABLE>

                                       i
<PAGE>   3

<TABLE>
<CAPTION>
                                                                                                       Page
                                                                                                       ----
<S>              <C>                                                                                   <C>

                                                  ARTICLE VI
                                  LIMITATION OF TRANSACTIONS; SUBORDINATION

SECTION 6.1       Limitation of Transactions.............................................................14
SECTION 6.2       Ranking................................................................................15

                                                 ARTICLE VII
                                                 TERMINATION

SECTION 7.1       Termination............................................................................15

                                                ARTICLE VIII
                                              INDEMNIFICATION

SECTION 8.1       Exculpation............................................................................15
SECTION 8.2       Indemnification........................................................................16

                                                 ARTICLE IX
                                               MISCELLANEOUS

SECTION 9.1       Successors and Assigns.................................................................16
SECTION 9.2       Amendments.............................................................................16
SECTION 9.3       Notices................................................................................16
SECTION 9.4       Benefit................................................................................17
SECTION 9.5       Governing Law..........................................................................17
SECTION 9.6       Genders................................................................................17
SECTION 9.7       Counterparts...........................................................................17

</TABLE>

                                       ii

<PAGE>   4

                    PREFERRED SECURITIES GUARANTEE AGREEMENT

     This GUARANTEE AGREEMENT (the "Preferred Securities Guarantee"), dated as
of June 30, 2000, is executed and delivered by FleetBoston Financial
Corporation, a Rhode Island corporation (the "Guarantor"), and The Bank of New
York, a New York banking corporation, as trustee (the "Preferred Guarantee
Trustee"), for the benefit of the Holders (as defined herein) of Fleet Capital
Trust VI, a Delaware statutory business trust (the "Issuer").

     WHEREAS, pursuant to an Amended and Restated Declaration of Trust (the
"Declaration"), dated as of June 30, 2000, among the trustees of the Issuer
named therein, the Guarantor, as sponsor, and the holders from time to time of
undivided beneficial interests in the assets of the Issuer, the Issuer is
issuing on the Closing Date up to 12,650,000 preferred securities, having an
aggregate liquidation amount of up to $316,250,000 designated as the 8.80% Trust
Originated Preferred Securities(SM)" ("TOPrS(SM)") (the "Preferred Securities");
and

     WHEREAS, as incentive for the Holders to purchase the Preferred Securities,
the Guarantor desires irrevocably and unconditionally to agree, to the extent
set forth in this Preferred Securities Guarantee, to pay to the Holders the
Guarantee Payments (as defined herein) and to make certain other payments on the
terms and conditions set forth herein.

     WHEREAS, the Guarantor is also executing and delivering a guarantee
agreement (the "Common Securities Guarantee") in substantially identical terms
to this Preferred Securities Guarantee for the benefit of the holders of the
Common Securities (as defined herein), except that if an Event of Default (as
defined in the Indenture), has occurred and is continuing, the rights of holders
of the Common Securities to receive Guarantee Payments under the Common
Securities Guarantee are subordinated to the rights of Holders to receive
Guarantee Payments under this Preferred Securities Guarantee.

     NOW, THEREFORE, in consideration of the purchase by each Holder, which
purchase the Guarantor hereby agrees shall benefit the Guarantor, the Guarantor
executes and delivers this Preferred Securities Guarantee for the benefit of the
Holders.

                                   ARTICLE I

                         DEFINITIONS AND INTERPRETATION

     SECTION 1.1 Definitions and Interpretation

     In this Preferred Securities Guarantee, unless the context otherwise
requires:

     (a) capitalized terms used in this Preferred Securities Guarantee but not
defined in the preamble above have the respective meanings assigned to them in
this Section 1.1;

     (b) any capitalized term not defined in either the preamble above or this
Section 1.1 shall have the respective meaning assigned to it in the Declaration
in effect as of the date hereof;

-------------
(SM) "Trust Originated Preferred Securities" and "TOPrS" are service marks of
Merrill Lynch & Co., Inc.

<PAGE>   5

     (c) a term defined anywhere in this Preferred Securities Guarantee has the
same meaning throughout;

     (d) all references to "the Preferred Securities Guarantee" or "this
Preferred Securities Guarantee" are to this Preferred Securities Guarantee as
modified, supplemented or amended from time to time;

     (e) all references in this Preferred Securities Guarantee to Articles and
Sections are to Articles and Sections of this Preferred Securities Guarantee,
unless otherwise specified;

     (f) a term defined in the Trust Indenture Act of 1939, as amended has the
same meaning when used in this Preferred Securities Guarantee, unless otherwise
defined in this Preferred Securities Guarantee or unless the context otherwise
requires; and

     (g) a reference to the singular includes the plural and vice versa.

     "Affiliate" has the same meaning as given to that term in Rule 405 of the
Securities Act of 1933, as amended, or any successor rule thereunder.

     "Authorized Officer" of a Person means any executive officer, president,
vice-president, assistant vice-president, treasurer, assistant treasurer,
secretary, assistant secretary or other officer of such Person generally
authorized to bind such Person.

     "Business Day" means any day other than a day on which federal or state
banking institutions in the Borough of Manhattan or The City of New York are
authorized or obligated by any law, executive order or regulation to close.

     "Closing Date" means the Closing Time and each Date of Delivery as defined
in the Purchase Agreement.

     "Common Securities" means the securities representing common undivided
beneficial interests in the assets of the Issuer.

     "Corporate Trust Office" means the office of the Preferred Guarantee
Trustee at which the corporate trust business of the Preferred Guarantee Trustee
shall, at any particular time, be principally administered, which office at the
date of execution of this Agreement is located at 101 Barclay Street, Floor 21
West, New York, New York 10286.

     "Covered Person" means any Holder or beneficial owner of Preferred
Securities.

     "Debentures" means the 8.80% Junior Subordinated Deferrable Interest
Debentures due 2030 issued by the Guarantor to the Issuer.

     "Event of Default" means a default by the Guarantor on any of its payment
or other obligations under this Preferred Securities Guarantee.

     "Guarantee Payments" means the following payments or distributions, without
duplication, with respect to the Preferred Securities, to the extent not paid or
made by the Issuer:

                                       2

<PAGE>   6

(i) any accrued and unpaid Distributions (as defined in the Declaration) that
are required to be paid on such Preferred Securities, to the extent the Issuer
shall have funds available therefor, (ii) the redemption price, including all
accrued and unpaid Distributions to the date of redemption (the "Redemption
Price"), to the extent the Issuer has funds available therefor, with respect to
any Preferred Securities called for redemption by the Issuer, and (iii) upon a
voluntary or involuntary dissolution, winding-up or termination of the Issuer
(other than in connection with the distribution of Debentures to the Holders or
the redemption of all of the Preferred Securities as provided in the
Declaration), the lesser of (a) the aggregate of the liquidation amount and all
accrued and unpaid Distributions on the Preferred Securities to the date of
payment, to the extent the Issuer shall have funds available therefor, and (b)
the amount of assets of the Issuer remaining available for distribution to
Holders in liquidation of the Issuer (in either case, the "Liquidation
Distribution"). If an event of default under the Indenture has occurred and is
continuing, the rights of holders of the Common Securities to receive payments
under the Common Securities Guarantee Agreement are subordinated to the rights
of Holders to receive Guarantee Payments.

     "Holder" means any holder, as registered on the books and records of the
Issuer, of any Preferred Securities; provided, however, that, in determining
whether the holders of the requisite percentage of Preferred Securities have
given any request, notice, consent or waiver hereunder, "Holder" shall not
include the Guarantor or any Affiliate of the Guarantor, but only to the extent
that the Issuer has actual knowledge of such ownership.

     "Indemnified Person" means the Preferred Guarantee Trustee, any Affiliate
of the Preferred Guarantee Trustee, or any officers, directors, shareholders,
members, partners, employees, representatives, nominees, custodians or agents of
the Preferred Guarantee Trustee.

     "Indenture" means the Indenture dated as of June 30, 2000, among the
Guarantor (the "Debenture Issuer") and The Bank of New York, as trustee, and any
indenture supplemental thereto pursuant to which certain subordinated debt
securities of the Debenture Issuer are to be issued to the Institutional Trustee
of the Issuer.

     "Majority in liquidation amount of the Securities" means, except as
provided by the Trust Indenture Act, a vote by Holder(s), voting separately as a
class, of more than 50% of the liquidation amount (including the stated amount
that would be paid on redemption, liquidation or otherwise, plus accrued and
unpaid Distributions to the date upon which the voting percentages are
determined) of all outstanding Preferred Securities.

     "Officers' Certificate" means, with respect to any Person, a certificate
signed by two Authorized Officers of such Person. Any Officers' Certificate
delivered with respect to compliance with a condition or covenant provided for
in this Preferred Securities Guarantee shall include:

     (a) a statement that each Authorized Officer signing the Officers'
Certificate has read the covenant or condition and the definition relating
thereto;

     (b) a brief statement of the nature and scope of the examination or
investigation undertaken by each Authorized Officer in rendering the Officers'
Certificate;

                                       3

<PAGE>   7

     (c) a statement that each such Authorized Officer has made such examination
or investigation as, in such officer's opinion, is necessary to enable such
Authorized Officer to express an informed opinion as to whether or not such
covenant or condition has been complied with; and

     (d) a statement as to whether, in the opinion of each such Authorized
Officer, such condition or covenant has been complied with.

     "Person" means a legal person, including any individual, corporation,
estate, partnership, joint venture, association, joint stock company, limited
liability company, trust, unincorporated association, or government or any
agency or political subdivision thereof, or any other entity of whatever nature.

     "Preferred Guarantee Trustee" means The Bank of New York, a New York
banking corporation, until a Successor Preferred Guarantee Trustee has been
appointed and has accepted such appointment pursuant to the terms of this
Preferred Securities Guarantee and thereafter means each such Successor
Preferred Guarantee Trustee.

     "Purchase Agreement" means the Purchase Agreement for the offer and sale of
Preferred Securities in the form of Exhibit C to the Declaration.

     "Resignation Request" has the meaning set forth in Section 4.2(c).

     "Responsible Officer" means, with respect to the Preferred Guarantee
Trustee, any officer within the Corporate Trust Office of the Preferred
Guarantee Trustee, including any vice president, any assistant vice president,
any assistant secretary, the treasurer, any assistant treasurer or other officer
of the Corporate Trust Office of the Preferred Guarantee Trustee customarily
performing functions similar to those performed by any of the above designated
officers and also means, with respect to a particular corporate trust matter,
any other officer to whom such matter is referred because of that officer's
knowledge of and familiarity with the particular subject.

     "Successor Preferred Guarantee Trustee" means a successor Preferred
Guarantee Trustee possessing the qualifications to act as Preferred Guarantee
Trustee under Section 4.1.

     "Trust Indenture Act" means the Trust Indenture Act of 1939, as amended.

                                   ARTICLE II

                               TRUST INDENTURE ACT

     SECTION 2.1 Trust Indenture Act; Application

     (a) This Preferred Securities Guarantee is subject to the provisions of the
Trust Indenture Act that are required to be part of this Preferred Securities
Guarantee and shall, to the extent applicable, be governed by such provisions.

                                       4

<PAGE>   8

     (b) If and to the extent that any provision of this Preferred Securities
Guarantee limits, qualifies or conflicts with the duties imposed by Sections 310
to 317, inclusive, of the Trust Indenture Act, such imposed duties shall
control.

     (c) The application of the Trust Indenture Act to this Preferred Securities
Guarantee shall not affect the nature of the Preferred Securities as equity
securities representing undivided beneficial interests in the assets of the
Issuer.

     SECTION 2.2 Lists of Holders of Securities

     (a) The Guarantor shall provide the Preferred Guarantee Trustee with a
list, in such form as the Preferred Guarantee Trustee may reasonably require, of
the names and addresses of the Holders ("List of Holders") as of such date, (i)
within one Business Day after January 1 and June 30 of each year, and (ii) at
any other time within 30 days of receipt by the Guarantor of a written request
for a List of Holders. Such list shall be as of a date no more than 14 days
before such List of Holders is given to the Preferred Guarantee Trustee. The
Guarantor shall not be obligated to provide such List of Holders if at any time
the List of Holders does not differ from the most recent List of Holders given
to the Preferred Guarantee Trustee by the Guarantor. The Preferred Guarantee
Trustee may destroy any List of Holders previously given to it on receipt of a
new List of Holders.

     (b) The Preferred Guarantee Trustee shall comply with its obligations under
Sections 311(a), 311(b) and Section 312(b) of the Trust Indenture Act.

     SECTION 2.3 Reports by the Preferred Guarantee Trustee

     (a) Within 60 days after April 15 of each year, the Preferred Guarantee
Trustee shall provide to the Holders such reports as are required by Section 313
of the Trust Indenture Act, if any, in the form and in the manner provided by
Section 313 of the Trust Indenture Act. The Preferred Guarantee Trustee shall
also comply with the requirements of Section 313(d) of the Trust Indenture Act.

     SECTION 2.4 Periodic Reports to Preferred Guarantee Trustee

     (a) The Guarantor shall provide to the Preferred Guarantee Trustee such
documents, reports and information as required by Section 314 (if any) and the
compliance certificate required by Section 314 of the Trust Indenture Act in the
form, in the manner and at the times required by Section 314 of the Trust
Indenture Act.

     SECTION 2.5 Evidence of Compliance with Conditions Precedent

     The Guarantor shall provide to the Preferred Guarantee Trustee such
evidence of compliance with any conditions precedent, if any, provided for in
this Preferred Securities Guarantee that relate to any of the matters set forth
in Section 314(c) of the Trust Indenture Act. Any certificate or opinion
required to be given by an officer pursuant to Section 314(c)(1) may be given in
the form of an Officers' Certificate.

                                       5

<PAGE>   9

     SECTION 2.6 Events of Default; Waiver

     (a) The Holders of a Majority in liquidation amount of Preferred Securities
may, by vote, on behalf of all of the Holders waive any past Event of Default
and its consequences. Upon such waiver, any such Event of Default shall cease to
exist, and any Event of Default arising therefrom shall be deemed to have been
cured, for every purpose of this Preferred Securities Guarantee, but no such
waiver shall extend to any subsequent or other default or Event of Default or
impair any right consequent thereon.

     (b) Notwithstanding the provisions of subsection (a) of this Section 2.6,
the right of any Holder of Preferred Securities to receive payment of the
Guarantee Payments in accordance with this Preferred Securities Guarantee, or to
institute suit for the enforcement of any such payment, shall not be impaired
without the consent of each such Holder.

     SECTION 2.7 Event of Default; Notice

     (a) The Preferred Guarantee Trustee shall, within 90 days after the
occurrence of an Event of Default, transmit by mail, first class postage
prepaid, to the Holders, notices of all Events of Default actually known to a
Responsible Officer of the Preferred Guarantee Trustee, unless such defaults
have been cured before the giving of such notice, provided, that, the Preferred
Guarantee Trustee shall be protected in withholding such notice if and so long
as a Responsible Officer in good faith determines that the withholding of such
notice is in the interests of the Holders of the Preferred Securities.

     (b) The Preferred Guarantee Trustee shall not be deemed to have actual
knowledge of any Event of Default unless the Preferred Guarantee Trustee shall
have received written notice, or of which a Responsible Officer charged with the
administration of this Preferred Securities Guarantee shall have obtained actual
knowledge.

     SECTION 2.8 Conflicting Interests

     The Declaration shall be deemed to be specifically described in this
Preferred Securities Guarantee for the purposes of clause (i) of the first
proviso contained in Section 310(b) of the Trust Indenture Act.

                                  ARTICLE III

                     POWERS, DUTIES AND RIGHTS OF PREFERRED
                                GUARANTEE TRUSTEE

     SECTION 3.1 Powers and Duties of the Preferred Guarantee Trustee

     (a) This Preferred Securities Guarantee shall be held by the Preferred
Guarantee Trustee in trust for the benefit of the Holders, and the Preferred
Guarantee Trustee shall not transfer its right, title and interest in this
Preferred Securities Guarantee to any Person except a Holder exercising his or
her rights pursuant to Section 5.4(d) or to a Successor Preferred Guarantee
Trustee on acceptance by such Successor Preferred Guarantee Trustee of its
appointment to act as Successor Preferred Guarantee Trustee. The right, title
and interest of the

                                       6

<PAGE>   10

Preferred Guarantee Trustee shall automatically vest in any Successor Preferred
Guarantee Trustee, and such vesting and cessation of title shall be effective
whether or not conveyancing documents have been executed and delivered pursuant
to the appointment of such Successor Preferred Guarantee Trustee.

     (b) If an Event of Default actually known to a Responsible Officer has
occurred and is continuing, the Preferred Guarantee Trustee shall enforce this
Preferred Securities Guarantee for the benefit of the Holders.

     (c) This Preferred Securities Guarantee and all moneys received by the
Preferred Guarantee Trustee hereunder in respect of the Guarantee Payments will
not be subject to any right, charge, security interest, lien or claim of any
kind in favor of, or for the benefit of, the Preferred Guarantee Trustee or its
agents or their creditors.

     (d) The Preferred Guarantee Trustee, before the occurrence of any Event of
Default and after the curing of all Events of Default that may have occurred,
shall undertake to perform only such duties as are specifically set forth in
this Preferred Securities Guarantee, and no implied covenants shall be read into
this Preferred Securities Guarantee against the Preferred Guarantee Trustee. In
case an Event of Default has occurred (that has not been cured or waived
pursuant to Section 2.6) and is actually known to a Responsible Officer of the
Preferred Guarantee Trustee, the Preferred Guarantee Trustee shall exercise such
of the rights and powers vested in it by this Preferred Securities Guarantee,
and use the same degree of care and skill in its exercise thereof, as a prudent
person would exercise or use under the circumstances in the conduct of his or
her own affairs.

     (e) No provision of this Preferred Securities Guarantee shall be construed
to relieve the Preferred Guarantee Trustee from liability for its own negligent
action, its own negligent failure to act, or its own willful misconduct, except
that:

          (i) prior to the occurrence of any Event of Default and after the
     curing or waiving of all such Events of Default that may have occurred:

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

               (B) in the absence of bad faith on the part of the Preferred
          Guarantee Trustee, the Preferred Guarantee Trustee may conclusively
          rely, as to the truth of the statements and the correctness of the
          opinions expressed therein, upon any certificates or opinions
          furnished to the Preferred Guarantee Trustee and conforming to the
          requirements of this Preferred Securities Guarantee; but in the case
          of any such certificates or opinions that by any provision hereof are
          specifically required to be furnished to the Preferred Guarantee
          Trustee, the

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<PAGE>   11

          Preferred Guarantee Trustee shall be under a duty to examine the same
          to determine whether or not they conform to the requirements of this
          Preferred Securities Guarantee;

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

          (iii) the Preferred Guarantee Trustee shall not be liable with respect
     to any action taken or omitted to be taken by it in good faith in
     accordance with the direction of the Holders of not less than a Majority in
     liquidation amount of the Preferred Securities relating to the time, method
     and place of conducting any proceeding for any remedy available to the
     Preferred Guarantee Trustee, or exercising any trust or power conferred
     upon the Preferred Guarantee Trustee under this Preferred Securities
     Guarantee; and

          (iv) no provision of this Preferred Securities Guarantee shall require
     the Preferred Guarantee Trustee to expend or risk its own funds or
     otherwise incur personal financial liability in the performance of any of
     its duties or in the exercise of any of its rights or powers, if the
     Preferred Guarantee Trustee shall have reasonable grounds for believing
     that the repayment of such funds or liability is not reasonably assured to
     it under the terms of this Preferred Securities Guarantee or indemnity,
     reasonably satisfactory to the Preferred Guarantee Trustee, against such
     risk or liability is not reasonably assured to it.

     SECTION 3.2 Certain Rights of Preferred Guarantee Trustee

     (a)  Subject to the provisions of Section 3.1:

          (i) The Preferred Guarantee Trustee may conclusively rely, and shall
     be fully protected in acting or refraining from acting upon, any
     resolution, certificate, statement, instrument, opinion, report, notice,
     request, direction, consent, order, bond, debenture, note, other evidence
     of indebtedness or other paper or document believed by it in good faith to
     be genuine and to have been signed, sent or presented by the proper party
     or parties.

          (ii) Any direction or act of the Guarantor contemplated by this
     Preferred Securities Guarantee shall be sufficiently evidenced by an
     Officers' Certificate.

          (iii) Whenever, in the administration of this Preferred Securities
     Guarantee, the Preferred Guarantee Trustee shall deem it desirable that a
     matter be proved or established before taking, suffering or omitting any
     action hereunder, the Preferred Guarantee Trustee (unless other evidence is
     herein specifically prescribed) may, in the absence of bad faith on its
     part, request and conclusively rely upon an Officers' Certificate which,
     upon receipt of such request, shall be promptly delivered by the Guarantor.

                                       8

<PAGE>   12

          (iv) The Preferred Guarantee Trustee shall have no duty to see to any
     recording, filing or registration of any instrument (or any rerecording,
     refiling or registration thereof).

          (v) The Preferred Guarantee Trustee may consult with counsel, and the
     written advice or opinion of such counsel with respect to legal matters
     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 advice or opinion. Such counsel may be counsel to the
     Guarantor or any of its Affiliates and may include any of its employees.
     The Preferred Guarantee Trustee shall have the right at any time to seek
     instructions concerning the administration of this Preferred Securities
     Guarantee from any court of competent jurisdiction.

          (vi) The Preferred Guarantee Trustee shall be under no obligation to
     exercise any of the rights or powers vested in it by this Preferred
     Securities Guarantee at the request or direction of any Holder, unless such
     Holder shall have provided to the Preferred Guarantee Trustee such security
     and indemnity, reasonably satisfactory to the Preferred Guarantee Trustee,
     against the costs, expenses (including attorneys' fees and expenses and the
     expenses of the Preferred Guarantee Trustee's agents, nominees or
     custodians) and liabilities that might be incurred by it in complying with
     such request or direction, including such reasonable advances as may be
     requested by the Preferred Guarantee Trustee; provided that, nothing
     contained in this Section 3.2(a)(vi) shall relieve the Preferred Guarantee
     Trustee, upon the occurrence of an Event of Default which has not been
     cured or waived, of its obligation to exercise the rights and powers vested
     in it by this Preferred Securities Guarantee and to use the same degree of
     care and skill in this exercise, as a prudent person would exercise or use
     under the circumstances in the conduct of his or her own affairs.

          (vii) The Preferred Guarantee Trustee shall not be bound to make any
     investigation into the facts or matters stated in any resolution,
     certificate, statement, instrument, opinion, report, notice, request,
     direction, consent, order, bond, debenture, note, other evidence of
     indebtedness or other paper or document, but the Preferred Guarantee
     Trustee, in its discretion, may make such further inquiry or investigation
     into such facts or matters as it may see fit.

          (viii) The Preferred Guarantee Trustee may execute any of the trusts
     or powers hereunder or perform any duties hereunder either directly or
     through agents, nominees, custodians or attorneys, and the Preferred
     Guarantee Trustee shall not be responsible for any misconduct or negligence
     on the part of any agent or attorney appointed with due care by it
     hereunder.

          (ix) Any action taken by the Preferred Guarantee Trustee or its agents
     hereunder shall bind the Holders, and the signature of the Preferred
     Guarantee Trustee or its agents alone shall be sufficient and effective to
     perform any such action. No third party shall be required to inquire as to
     the authority of the Preferred Guarantee Trustee to so act or as to its
     compliance with any of the terms and provisions of this Preferred

                                       9
<PAGE>   13

     Securities Guarantee, both of which shall be conclusively evidenced by the
     Preferred Guarantee Trustee's or its agent's taking such action.

          (x) Whenever in the administration of this Preferred Securities
     Guarantee the Preferred Guarantee Trustee shall deem it desirable to
     receive instructions with respect to enforcing any remedy or right or
     taking any other action hereunder, the Preferred Guarantee Trustee (i) may
     request instructions from the Holders of a Majority in liquidation amount
     of the Preferred Securities, (ii) may refrain from enforcing such remedy or
     right or taking such other action until such instructions are received, and
     (iii) shall be protected in conclusively relying on or acting in accordance
     with such instructions.

     (b)      No provision of this Preferred Securities Guarantee shall be
deemed to impose any duty or obligation on the Preferred Guarantee Trustee to
perform any act or acts or exercise any right, power, duty or obligation
conferred or imposed on it in any jurisdiction in which it shall be illegal, or
in which the Preferred Guarantee Trustee shall be unqualified or incompetent in
accordance with applicable law, to perform any such act or acts or to exercise
any such right, power, duty or obligation. No permissive power or authority
available to the Preferred Guarantee Trustee shall be construed to be a duty.

     SECTION 3.3 Not Responsible for Recitals or Issuance of Preferred
Securities Guarantee

     The recitals contained in this Preferred Securities Guarantee shall be
taken as the statements of the Guarantor, and the Preferred Guarantee Trustee
does not assume any responsibility for their correctness. The Preferred
Guarantee Trustee makes no representation as to the validity or sufficiency of
this Preferred Securities Guarantee.

                                   ARTICLE IV

                           PREFERRED GUARANTEE TRUSTEE

     SECTION 4.1 Preferred Guarantee Trustee; Eligibility

     (a)  There shall at all times be a Preferred Guarantee Trustee which shall:

          (i)  not be an Affiliate of the Guarantor; and

          (ii) be a corporation organized and doing business under the laws of
     the United States of America or any State or territory thereof or of the
     District of Columbia, or a corporation or Person permitted by the
     Securities and Exchange Commission to act as an institutional trustee under
     the Trust Indenture Act, authorized under such laws to exercise corporate
     trust powers, having a combined capital and surplus of at least 50 million
     U.S. dollars ($50,000,000), and subject to supervision or examination by
     federal, state, territorial or District of Columbia authority. If such
     corporation publishes reports of condition at least annually, pursuant to
     law or to the requirements of the supervising or examining authority
     referred to above, then, for the purposes of this Section 4.1(a)(ii), the
     combined capital and surplus of such corporation shall be deemed to be its
     combined capital and surplus as set forth in its most recent report of
     condition so published.

                                       10

<PAGE>   14

     (b)  If at any time the Preferred Guarantee Trustee shall cease to be
eligible to so act under Section 4.1(a), the Preferred Guarantee Trustee shall
immediately resign in the manner and with the effect set out in Section 4.2(c).

     (c)  If the Preferred Guarantee Trustee has or shall acquire any
"conflicting interest" within the meaning of Section 310(b) of the Trust
Indenture Act, the Preferred Guarantee Trustee and Guarantor shall in all
respects comply with the provisions of Section 310(b) of the Trust Indenture
Act.

     SECTION 4.2 Appointment, Removal and Resignation of Preferred Guarantee
Trustee

     (a)  Subject to Section 4.2(b), the Preferred Guarantee Trustee may be
appointed or removed without cause at any time by the Guarantor.

     (b)  The Preferred Guarantee Trustee shall not be removed in accordance
with Section 4.2(a) until a Successor Preferred Guarantee Trustee has been
appointed and has accepted such appointment by written instrument executed by
such Successor Preferred Guarantee Trustee and delivered to the Guarantor and to
the Preferred Guarantee Trustee being removed.

     (c)  The Preferred Guarantee Trustee appointed to office shall hold office
until a Successor Preferred Guarantee Trustee shall have been appointed or until
its removal or resignation. The Preferred Guarantee Trustee may resign from
office (without need for prior or subsequent accounting) by an instrument (a
"Resignation Request") in writing executed by the Preferred Guarantee Trustee
and delivered to the Guarantor which resignation shall take effect upon such
delivery or upon such later date as is specified therein; provided, however,
that no such resignation of the Preferred Guarantee Trustee shall be effective
until a Successor Preferred Guarantee Trustee has been appointed and has
accepted such appointment by instrument in writing executed by such Successor
Preferred Guarantee Trustee and delivered to the Guarantor and the resigning
Preferred Guarantee Trustee.

     (d)  If no Successor Preferred Guarantee Trustee shall have been appointed
and accepted appointment as provided in this Section 4.2 within 60 days after
delivery to the Guarantor of a Resignation Request, the resigning Preferred
Guarantee Trustee may petition at the expense of the Company any court of
competent jurisdiction for appointment of a Successor Preferred Guarantee
Trustee. Such court may thereupon, after prescribing such notice, if any, as it
may deem proper, appoint a Successor Preferred Guarantee Trustee.

     (e)  No Preferred Guarantee Trustee shall be liable for the acts or
omissions to act of any Successor Preferred Guarantee Trustee.

     (f)  Upon termination of this Preferred Securities Guarantee or removal or
resignation of the Preferred Guarantee Trustee pursuant to this Section 4.2, the
Guarantor shall pay to the Preferred Guarantee Trustee all amounts accrued to
the date of such termination, removal or resignation.

                                       11

<PAGE>   15

                                   ARTICLE V

                                   GUARANTEE

     SECTION 5.1 Guarantee

     The Guarantor irrevocably and unconditionally agrees to pay in full to the
Holders the Guarantee Payments (without duplication of amounts theretofore paid
by the Issuer), as and when due, regardless of any defense, right of set-off or
counterclaim that the Issuer may have or assert. The Guarantor's obligation to
make a Guarantee Payment may be satisfied by direct payment of the required
amounts by the Guarantor to the Holders or by causing the Issuer to pay such
amounts to the Holders.

     SECTION 5.2 Waiver of Notice and Demand

     The Guarantor hereby waives notice of acceptance of this Preferred
Securities Guarantee and of any liability to which it applies or may apply,
presentment, demand for payment, any right to require a proceeding first against
the Issuer or any other Person before proceeding against the Guarantor, protest,
notice of nonpayment, notice of dishonor, notice of redemption and all other
notices and demands.

     SECTION 5.3 Obligations Not Affected

     The obligations, covenants, agreements and duties of the Guarantor under
this Preferred Securities Guarantee shall in no way be affected or impaired by
reason of the happening from time to time of any of the following:

     (a)  the release or waiver, by operation of law or otherwise, of the
performance or observance by the Issuer of any express or implied agreement,
covenant, term or condition relating to the Preferred Securities to be performed
or observed by the Issuer;

     (b)  the extension of time for the payment by the Issuer of all or any
portion of the Distributions, Redemption Price, Liquidation Distribution or any
other sums payable under the terms of the Preferred Securities or the extension
of time for the performance of any other obligation under, arising out of, or in
connection with, the Preferred Securities (other than an extension of time for
payment of Distributions, Redemption Price, Liquidation Distribution or other
sum payable that results from the extension of any interest payment period on
the Debentures or any extension of the maturity date of the Debentures permitted
by the Indenture);

     (c)  any failure, omission, delay or lack of diligence on the part of the
Holders to enforce, assert or exercise any right, privilege, power or remedy
conferred on the Holders pursuant to the terms of the Preferred Securities, or
any action on the part of the Issuer granting indulgence or extension of any
kind;

     (d)  the voluntary or involuntary liquidation, dissolution, sale of any
collateral, receivership, insolvency, bankruptcy, assignment for the benefit of
creditors, reorganization, arrangement, composition or readjustment of debt of,
or other similar proceedings affecting, the Issuer or any of the assets of the
Issuer;

                                       12

<PAGE>   16

     (e)  any invalidity of, or defect or deficiency in, the Preferred
Securities;

     (f)  the settlement or compromise of any obligation guaranteed hereby or
hereby incurred; or

     (g)  any other circumstance whatsoever that might otherwise constitute a
legal or equitable discharge or defense of a guarantor, it being the intent of
this Section 5.3 that the obligations of the Guarantor hereunder shall be
absolute and unconditional under any and all circumstances.

     There shall be no obligation of the Holders to give notice to, or obtain
consent of, the Guarantor with respect to the happening of any of the foregoing.

     SECTION 5.4 Enforcement of Guarantee; Rights of Holders

     The Guarantor and the Preferred Guarantee Trustee expressly acknowledge
that:

     (a)  this Preferred Securities Guarantee will be deposited with the
Preferred Guarantee Trustee to be held for the benefit of the Holders;

     (b)  the Preferred Guarantee Trustee has the right to enforce this
Preferred Securities Guarantee on behalf of the Holders;

     (c)  the Holders of a Majority in liquidation amount of the Securities have
the right to direct the time, method and place of conducting any proceeding for
any remedy available to the Preferred Guarantee Trustee in respect of this
Preferred Securities Guarantee or exercising any trust or power conferred upon
the Preferred Guarantee Trustee under this Preferred Securities Guarantee; and

     (d)  any Holder may institute a legal proceeding directly against the
Guarantor to enforce the Preferred Guarantee Trustee's rights and the
obligations of the Guarantor under this Preferred Securities Guarantee, without
first instituting a legal proceeding against the Issuer, the Preferred Guarantee
Trustee or any other person or entity, and the Guarantor waives any right or
remedy to require that any action be brought first against the Issuer or any
other person or entity before proceeding directly against the Guarantor.

     SECTION 5.5 Guarantee of Payment

     This Preferred Securities Guarantee creates a guarantee of payment and not
of collection. This Preferred Securities Guarantee will not be discharged except
by payment of the Guarantee Payments in full (without duplication of amounts
therefor paid by the Issuer).

     SECTION 5.6 Subrogation

     The Guarantor shall be subrogated to all (if any) rights of the Holders
against the Issuer in respect of any amounts paid to such Holders by the
Guarantor under this Preferred Securities Guarantee; provided, however, that the
Guarantor shall not (except to the extent required by mandatory provisions of
law) be entitled to enforce or exercise any right that it may acquire by

                                       13

<PAGE>   17

way of subrogation or any indemnity, reimbursement or other agreement, in all
cases as a result of payment under this Preferred Securities Guarantee, if, at
the time of any such payment, any amounts are due and unpaid under this
Preferred Securities Guarantee. If any amount shall be paid to the Guarantor in
violation of the preceding sentence, the Guarantor agrees to hold such amount in
trust for the Holders and to pay over such amount to the Holders.

     SECTION 5.7 Independent Obligations

     The Guarantor acknowledges that its obligations hereunder are independent
of the obligations of the Issuer with respect to the Preferred Securities, and
that the Guarantor shall be liable as principal and as debtor hereunder to make
Guarantee Payments pursuant to the terms of this Preferred Securities Guarantee
notwithstanding the occurrence of any event referred to in subsections (a)
through (g), inclusive, of Section 5.3 hereof.

                                   ARTICLE VI

                    LIMITATION OF TRANSACTIONS; SUBORDINATION

     SECTION 6.1 Limitation of Transactions

     So long as any Preferred Securities remain outstanding, if (a) there shall
have occurred an Event of Default, (b) there shall have occurred an Event of
Default (as defined under the Indenture) or (c) the Guarantor has exercised its
option to defer interest payments on the Debentures by extending the interest
payment period as provided in Article IV of the First Supplemental Indenture to
the Indenture, and such period or extension thereof shall be continuing, then
(i) the Guarantor shall not declare or pay any dividend on, make any
distribution with respect to, or redeem, purchase, acquire, or make a
liquidation payment with respect to, any of its capital stock (other than (A)
purchases or acquisitions of shares of Guarantor's common stock in connection
with the satisfaction by the Guarantor of its obligations under any employee
benefit plans or any other contractual obligation of the Guarantor (other than a
contractual obligation ranking pari passu with or junior to the Debentures), (B)
as a result of a reclassification of the Guarantor's capital stock or the
exchange or conversion of one class or series of the Guarantor's capital stock
for another class or series of the Guarantor's capital stock or (C) the purchase
of fractional interests in shares of the Guarantor's capital stock pursuant to
the conversion or exchange provisions of such capital stock or the security
being converted or exchanged), (ii) the Guarantor shall not make any payment of
interest, principal or premium, if any, on or repay, repurchase or redeem any
debt securities issued by the Guarantor that rank pari passu with or junior to
the Debentures and (iii) the Guarantor shall not make any guarantee payments
with respect to the foregoing (other than pursuant to this Preferred Securities
Guarantee).

     In addition, so long as any Preferred Securities remain outstanding, the
Guarantor (i) will remain the sole direct or indirect owner of all of the
outstanding Common Securities; provided that any permitted successor of the
Guarantor under the Indenture may succeed to the Guarantor's ownership of the
Common Securities and (ii) will not take any action which would cause the Issuer
to cease to be treated as a grantor trust for United States federal income tax
purposes except in connection with a distribution of Debentures as provided in
the Declaration.

                                       14

<PAGE>   18

     SECTION 6.2 Ranking

     This Preferred Securities Guarantee will constitute an unsecured obligation
of the Guarantor and will rank (i) subordinate and junior in right of payment to
all other liabilities of the Guarantor, except those made pari passu or
subordinate by their terms, (ii) pari passu with the most senior preferred or
preference stock now or hereafter issued by the Guarantor and with any guarantee
now or hereafter entered into by the Guarantor in respect of any preferred or
preference stock of any Affiliate of the Guarantor, and (iii) senior to the
Guarantor's common stock.

                                  ARTICLE VII

                                  TERMINATION

     SECTION 7.1 Termination

     This Preferred Securities Guarantee shall terminate and be of no further
force and effect upon (i) full payment of the Redemption Price of all Preferred
Securities, (ii) upon the distribution of the Debentures to all of the Holders
or (iii) upon full payment of the amounts payable in accordance with the
Declaration upon liquidation of the Issuer. Notwithstanding the foregoing, this
Preferred Securities Guarantee will continue to be effective or will be
reinstated, as the case may be, if at any time any Holder must restore payment
of any sums paid under the Preferred Securities or under this Preferred
Securities Guarantee.

                                  ARTICLE VIII

                                 INDEMNIFICATION

     SECTION 8.1 Exculpation

     (a)  No Indemnified Person shall be liable, responsible or accountable in
damages or otherwise to the Guarantor or any Covered Person for any loss, damage
or claim incurred by reason of any act or omission performed or omitted by such
Indemnified Person in good faith in accordance with this Preferred Securities
Guarantee and in a manner that such Indemnified Person reasonably believed to be
within the scope of the authority conferred on such Indemnified Person by this
Preferred Securities Guarantee or by law, except that an Indemnified Person
shall be liable for any such loss, damage or claim incurred by reason of such
Indemnified Person's negligence or willful misconduct with respect to such acts
or omissions.

     (b)  An Indemnified Person shall be fully protected in relying in good
faith upon the records of the Guarantor and upon such information, opinions,
reports or statements presented to the Guarantor by any Person as to matters the
Indemnified Person reasonably believes are within such other Person's
professional or expert competence and who has been selected with reasonable care
by or on behalf of the Guarantor, including information, opinions, reports or
statements as to the value and amount of the assets, liabilities, profits,
losses, or any other facts pertinent to the existence and amount of assets from
which Distributions to Holders might properly be paid.

                                       15

<PAGE>   19

     SECTION 8.2 Indemnification

     To the fullest extent permitted by applicable law, the Guarantor agrees to
indemnify each Indemnified Person for, and to hold each Indemnified Person
harmless against, any loss, liability or expense incurred by such Indemnified
Person by reason of any act or omission performed or omitted by such Indemnified
Person without negligence or bad faith on its part, arising out of or in
connection with the acceptance or administration of the trust or trusts
hereunder, including the costs and expenses (including reasonable legal fees and
expenses) of defending itself against, or investigating, any claim or liability
in connection with the exercise or performance of any of its powers or duties
hereunder. The obligation to indemnify as set forth in this Section 8.2 shall
survive the resignation or removal of the Preferred Guarantee Trustee and the
termination of this Preferred Securities Guarantee.

                                   ARTICLE IX

                                  MISCELLANEOUS

     SECTION 9.1 Successors and Assigns

     All guarantees and agreements contained in this Preferred Securities
Guarantee shall bind the successors, assigns, receivers, trustees and
representatives of the Guarantor and shall inure to the benefit of the Holders
of the Preferred Securities then outstanding. Except in connection with any
merger or consolidation of the Guarantor with or into another entity or any
sale, transfer or lease of the Guarantor's assets to another entity, each as
permitted by the Indenture, the Guarantor may not assign its rights or delegate
its obligations under this Preferred Securities Guarantee without the prior
approval of the Holders of at least a Majority in liquidation amount of the
Preferred Securities then outstanding.

     SECTION 9.2 Amendments

     Except with respect to any changes that do not adversely affect the rights
of Holders (in which case no consent of Holders will be required), this
Preferred Securities Guarantee may only be amended with the prior approval of
the Holders of at least a Majority in liquidation amount of all the outstanding
Preferred Securities. The provisions of Section 12.2 of the Declaration with
respect to meetings of Holders apply to the giving of such approval.

     SECTION 9.3 Notices

     All notices provided for in this Preferred Securities Guarantee shall be in
writing, duly signed by the party giving such notice, and shall be delivered,
telecopied or mailed by first class mail, as follows:

     (a) If given to the Preferred Guarantee Trustee, at the Preferred Guarantee
Trustee's mailing address set forth below (or such other address as the
Preferred Guarantee Trustee may give notice of to the Holders):

                           The Bank of New York
                           101 Barclay Street

                                       16

<PAGE>   20

                           Floor 21 West
                           New York, New York 10286
                           Attention:  Corporate Trust Trustee Administration

     (b) If given to the Guarantor, at the Guarantor's mailing address set forth
below (or such other address as the Guarantor may give notice of to the
Holders):

                           FleetBoston Financial Corporation
                           100 Federal Street
                           Boston, Massachusetts 02110
                           Attention:  General Counsel

     (c) If given to any Holder, at the address set forth on the books and
records of the Issuer.

     All such notices shall be deemed to have been given when received in
person, telecopied with receipt confirmed, or mailed by first class mail,
postage prepaid except that if a notice or other document is refused delivery or
cannot be delivered because of a changed address of which no notice was given,
such notice or other document shall be deemed to have been delivered on the date
of such refusal or inability to deliver.

     SECTION 9.4 Benefit

     This Preferred Securities Guarantee is solely for the benefit of the
Holders and, subject to Section 3.1(a), is not separately transferable from the
Preferred Securities.

     SECTION 9.5 Governing Law

     THIS PREFERRED SECURITIES GUARANTEE SHALL BE GOVERNED BY, AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK AND ALL RIGHTS
AND REMEDIES SHALL BE GOVERNED BY SUCH LAWS WITHOUT REGARD TO PRINCIPLES OF
CONFLICT OF LAWS.

     SECTION 9.6 Genders

     The masculine, feminine and neuter genders used herein shall include the
masculine, feminine and neuter genders.

     SECTION 9.7 Counterparts

     This Preferred Securities Guarantee may be executed in counterparts, each
of which shall be an original, but such counterparts shall together constitute
one and the same instrument.

                                       17

<PAGE>   21

THIS PREFERRED SECURITIES GUARANTEE is executed as of the day and year first
above written.

FLEETBOSTON FINANCIAL CORPORATION,
as Guarantor

By:  /s/ DOUGLAS L. JACOBS
     ---------------------------------------------------
     Name: Douglas L. Jacobs
     Title:  Senior Vice President and Treasurer

THE BANK OF NEW YORK,
as Preferred Guarantee Trustee

By:  /s/ MICHAEL CULHANE
     ---------------------------------------------------
     Name: Michael Culhane
     Title:  Vice President

                                       18

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