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                                                                    EXHIBIT 4.25

                          SECOND SUPPLEMENTAL INDENTURE

THIS SECOND SUPPLEMENTAL INDENTURE ("Second Supplemental Indenture") dated as of
February 28, 2003, by and between M&T Bank Corporation, a corporation organized
and existing under the laws of the State of New York ("M&T"), having its
principal executive office at One M&T Plaza, Buffalo, New York 14203, and
Deutsche Bank Trust Company Americas f/k/a Bankers Trust Company, a banking
corporation organized and existing under the laws of the State of New York (the
"Trustee"), having its Corporate Trust Office at 60 Wall Street, MS NYC60-2515,
New York, NY 10005.

                                    RECITALS

WHEREAS, Keystone Financial Mid-Atlantic Funding Corp., had been a corporation
organized and existed under the laws of the Commonwealth of Pennsylvania
("Keystone Funding"), Keystone Financial, Inc., a corporation organized and
existing under the laws of the Commonwealth of Pennsylvania ("Keystone"), and
the Trustee entered into an Indenture, dated as of May 1, 1997 (the "Original
Indenture"), pursuant to which Senior Debt Securities (the "Securities") had
been issued by Keystone Funding and guaranteed by the Guarantor; and

WHEREAS, M&T and Olympia Financial Corp ("Olympia" or the "Guarantor") entered
into an Agreement and Plan of Reorganization, dated as of May 16, 2000 with
Keystone; and

WHEREAS, Olympia and Keystone entered into an Agreement and Plan of Merger,
dated as of May 16, 2000, providing for, among other things, the merger of
Keystone with and into Olympia, with Olympia as the surviving entity; and

WHEREAS, the Guarantor and the Trustee entered into the First Supplemental
Indenture, dated as of October 6, 2000 (the "First Supplemental Indenture,"
together with the Original Indenture, the "Indenture"); and

WHEREAS, on the date of this Second Supplemental Indenture, the Guarantor has
been merged with and into M&T, with M&T being the surviving corporation (the
"Merger"), whereupon the separate corporate existence of the Guarantor has
ceased; and

WHEREAS, M&T has delivered to the Trustee an Officers' Certificate stating that
the Merger and this Second Supplemental Indenture comply with Article Nine and
Article Ten of the Indenture and that all conditions precedent therein provided
for relating to the Merger have been complied with, and an Opinion of Counsel to
the same effect; and

NOW, THEREFORE, in compliance with Article Nine and Article Ten of the Indenture
and in consideration of the covenants contained herein and intending to be
legally bound hereby, M&T and the Trustee, for the equal and proportionate
benefit of all the Holders of the Securities, agree as follows:

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1.       ASSUMPTION OF PAYMENT AND PERFORMANCE. M&T hereby expressly assume all
of the rights and obligations of the Guarantor and the performance of every
covenant and condition of the Indenture of the Guarantor (as defined therein)
thereunder to be performed or observed.

2.       PARTICULAR REPRESENTATIONS OF OLYMPIA.

The M&T represents the following:

(a)      It is a corporation organized and existing under the laws of the State
of New York; and

(b)      Immediately after the effective date of the Merger, no Event of Default
or Default, and no event which, after notice or lapse of time or both, would
become an Event of Default or Default, has happened and is continuing.

3.       SUCCESSION; EFFECT OF SECOND SUPPLEMENTAL INDENTURE.

(a)      As of the date of this Second Supplemental Indenture, M&T has succeeded
to and been substituted for, and does, hereby succeed to and become substituted
for, and may exercise every right and power of, the Guarantor under the
Indenture, with the same effect as if Olympia had been named as the "Guarantor"
therein.

(b)      Upon the execution of this Second Supplemental Indenture, the Indenture
has been and hereby is modified in accordance herewith, and this Second
Supplemental Indenture forms a part of the Indenture for all purposes; and every
Holder of a Security heretofore or hereafter authenticated and delivered under
the Indenture shall be bound hereby.

(c)      The recitals contained herein shall be taken as statements of M&T and
the Trustee assumes no responsibility for their correctness. The Trustee makes
no representations as to the validity or the sufficiency of this Second
Supplemental Indenture.

(d)      All terms used in this Second Supplemental Indenture which are defined
in the Indenture shall, for all purposes hereof, have the respective meanings
specified in the Indenture, unless the context otherwise specifies or requires.

(e)      Securities authenticated and delivered on and after the date hereof
shall bear the following notation, which may be printed or typewritten thereon:

                  "Effective February 28, 2003, Olympia Financial Corp.
                  ("Olympia"), a Delaware corporation, was merged with and into
                  M&T Bank Corporation ("M&T"), a New York corporation. Pursuant
                  to the Second Supplemental Indenture, dated as of February 28,
                  2003, M&T has assumed the obligations of Olympia as guarantor
                  of the Securities and the performance of every covenant and
                  condition of the Indenture on the part of Olympia to be
                  performed or observed."

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If M&T shall so determine, new Securities so modified as to conform to the
Indenture as hereby supplemented, in form satisfactory to the Trustee, may at
any time hereafter be prepared and executed by M&T and authenticated and
delivered by the Trustee in exchange for the Securities then Outstanding, and
thereafter the notation herein provided shall no longer be required. Anything
herein or in the Indenture to the contrary notwithstanding, the failure to affix
the notation herein provided to any Security or to exchange any Security for a
new Security modified as herein provided shall not affect any of the rights of
the Holder of such Security.

4.       GOVERNING LAW. This Second Supplemental Indenture shall be governed by
and construed in accordance with the laws of the jurisdiction that govern the
Indenture and its construction.

5.       ACCEPTANCE OF TRUSTEE. The Trustee hereby accepts the trusts in this
Second Supplemental Indenture declared and provided, upon the terms and
conditions herein set forth.

6.       COUNTERPARTS. This Second 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.

       [Remainder of this page left intentionally blank, signatures appear
                            on the following page.]

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

[Corporate Seal]                   M&T BANK CORPORATION

Attest:

/s/ Marie King                     By: /s/ Michael P. Pinto
-----------------------------          ----------------------------------
Marie King                             Michael P. Pinto
Corporate Secretary                    Executive Vice President and
                                       Chief Financial Officer

                                   Deutsche Bank Trust Company Americas
                                   f/k/a Bankers Trust Company

[Corporate Seal]

Attest:

/s/ Jason Burstock                 By: /s/ Michele H. Y. Voon
-----------------------------          ----------------------------------
                                       Michele H. Y. Voon
                                       Associate

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STATE OF NEW YORK               )
                                ) ss:
COUNTY OF ERIE                  )

On this 28th day of February, 2003 before me personally appeared Michael P.
Pinto, to me known, who, being by me duly sworn, did depose and say that he is
an Executive Vice President and the Chief Financial Officer of M&T Bank
Corporation, one of the corporations described in and which executed the
foregoing instrument; that he knows the seal of said corporation; that the seal
affixed to 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/ Brian R. Yoshida
                                  ------------------------------
                                  Notary Public

[Notary Seal]

My commission expires: 3/29/2007

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STATE OF NEW YORK               )
                                ) ss:
COUNTY OF NEW YORK              )

On this 5th day of March, 2003 before me personally appeared Michele H. Y. Voon,
to me known, who, being by me duly sworn, did depose and say that she is a
Associate of Deutsche Bank Trust Company Americas f/k/a Bankers Trust Company,
one of the corporations described in and which executed the foregoing
instrument; that she knows the seal of said corporation; that the seal affixed
to said instrument is such corporate seal; that it was so affixed by authority
of the Board of Directors of said corporation; and that she signed her name
thereto by like authority.

                                /s/ Annie Jaghatspanyan
                                -----------------------------
                                Notary Public

[Notary Seal]

My commission expires: 7/30/2005

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