EXHIBIT 10.4


                      SERVICE AND NONCOMPETITION AGREEMENT
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         THIS SERVICE AND NONCOMPETITION AGREEMENT (this "Agreement") is made
and entered into as of June 19, 2001, between CNB Financial Corp., a New York
corporation ("CNB"), NBT Bancorp Inc., a Delaware corporation (the "Company"),
and Donald L. Brass ("Executive"); and

         WHEREAS, upon the terms and subject to the conditions set forth in the
Agreement and Plan of Merger, dated as of the date hereof, by and between CNB
and the Company (the "Merger Agreement"), CNB will merge into the Company (the
"Merger"); and

         WHEREAS, CNB and the Company have determined that it is critical that
Executive continue to serve as Chief Executive Officer of CNB through the date
of the consummation of the Merger pursuant to the Merger Agreement (the
"Effective Time"); and

         WHEREAS, because of Executive's abilities and his knowledge of, and
reputation in, the markets where CNB conducts its business, the Company has
determined that it is essential to obtain a commitment from Executive not to
compete against the Company in those markets and not to solicit to employee the
Company's employees for a three year period after the Effective Time.

         NOW, THEREFORE, in consideration of the foregoing and of the mutual
covenants and agreements hereinafter set forth, it is hereby agreed as follows:

         1. Service as Chief Executive Officer. In recognition of the importance
of maintaining the current leadership of CNB through the Effective Time and in
light of the fact that the Company will terminate Executive's employment after
the Effective Time, Executive agrees that he shall continue to serve as Chief
Executive Officer of CNB until the earliest of (i) the Effective Time, (ii) the
date that the Merger Agreement is terminated in accordance with Section 12
thereof, and (iii) the date that CNB terminates Executive's employment for any
reason. Executive further agrees that, for the 30 day period prior to the
Effective Time, any vacation to be taken by Executive shall be scheduled in
consultation with the Company and shall be available only to the extent it does
not materially interfere with consummation of the Merger.

2.       Covenant Not to Compete.

         (a) The parties acknowledge: (i) that as a result of the Merger, the
Company will be engaged in the business of banking in those markets where CNB
currently conducts its banking business; (ii) that Executive has developed
special expertise and a recognized reputation in CNB's current markets; and
(iii) that if Executive were to undertake efforts in competition with the
Company in CNB's current market areas the result would be substantial and
irreparable damage to the Company.

         (b) For the three year period commencing at the Effective Time,
Executive shall not solicit or accept, directly or by assisting others, any
business (other than business in an area outside of twenty miles in which the
Company or any of its subsidiaries is competitively engaged) customers or
prospective customers of the Company whom Executive has served or solicited
during the course of his employment by CNB.

         (c) For the three year period commencing at the Effective Time,
Executive shall not, directly or indirectly, either for Executive's own benefit
or purpose or for the benefit or purpose of any person or entity other than the
Company or any of its subsidiaries, employ or offer to employ, call on, or
actively interfere with the Company's or any of its subsidiaries' relationship
with, or attempt to divert or entice away, any officer of the Company or any of
its subsidiaries who was an officer of CNB or any of its subsidiaries
immediately prior to the Effective Time.

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         (d) Executive recognizes that his obligations under Section 2 hereof
(the "Restrictive Covenant") is a reasonable means of protecting the Company
from competition by him and agrees that any breach of the Restrictive Covenant
may result in irreparable damage and injury to the Company, and that the Company
will be entitled to injunctive relief in any court of competent jurisdiction
without the necessity of posting any bond.

3.       Confidentiality.

         (a) Executive shall hold in strict confidence and shall not disclose,
directly or indirectly, to any third party, person, firm, corporation or other
entity, irrespective of whether such person or entity is a competitor of the
Company or is engaged in a business similar to that of the Company, any trade
secrets, customer lists or other proprietary information of the Company obtained
by Executive while serving as Chief Executive Officer of CNB.

         (b) Notwithstanding the foregoing  limitations,  Executive shall not be
required to keep  confidential  pursuant to this Section 3 any  confidential  or
proprietary  information  that:  (i) is known or available  through other lawful
sources,  (ii) is or becomes  publicly known or generally  known in the industry
through  no fault of  Executive  or his  agents,  or  (iii)  is  required  to be
disclosed pursuant to any statutes, laws, rules, regulations, ordinances, codes,
directives,   writs,   injunctions,   decrees,   judgments  and  orders  of  any
governmental body.

         Compensation. In consideration of Executive's continued service as
Chief Executive Officer, the Restrictive Covenant, and Executive's other
obligations hereunder, the Company agrees that:

         (c) The Company shall pay to Executive at the Effective Time a lump sum
amount, in cash, equal to $1,100,000.

         (d) For a period of three years after the Effective Time, the Company
shall provide to Executive, at no cost to him, life insurance and health
insurance (collectively, "Welfare Benefits") that are not less favorable in all
respects to those that Executive was receiving immediately prior to the
Effective Time; provided, however, that the medical coverage provided shall be
family medical coverage that also covers Executive's spouse and any dependents.
Executive will be entitled to elect to change his level of coverage and/or his
choice of coverage options with respect to the Welfare Benefits provided by the
Company to Executive to the same extent that actively employed senior executives
of the Company are permitted to make such changes.

         (e) Prior to the Effective Time, CNB shall take all necessary and
appropriate actions to (i) cause $28,000 to be contributed to the annuity
contract provided for under the terms of the Supplemental Retirement Annuity
Agreement (the "SRAA") between Executive and CNB, dated May 15, 2000, (ii) cause
the transfer of such annuity contract to a "rabbi trust," the terms of which
shall provide for the payment of benefits to Executive and his beneficiaries in
accordance with the terms of the SRAA, and (iii) amend the SRAA as necessary or
appropriate to reflect the terms of this Section 4(c).

4.       Other Plans and Benefits; Automobile Lease.

         (a) The Company agrees that in addition to any compensation and
benefits provided for in this Agreement, Executive shall be entitled to benefits
in accordance with the plans, practices, programs and policies of CNB which
covered Executive, or in which Executive participated, prior to the Effective
Time, including but not limited to the Deferred Compensation Plan for Certain
Executive Employees and Directors of Central National Bank, Canajoharie (the
"DCP") and the SRAA.

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         (b) Prior to the Effective Time, CNB shall take, or cause to be taken,
all such actions as may be necessary or appropriate to (i) relieve Executive of
all liability and obligation under Executive's existing lease of a 2001 Cadillac
and to cause Executive to be indemnified for any liability or obligation with
respect to such lease or automobile and (ii) amend the DCP to provide that
benefit payments to Executive under the DCP shall be made only upon at least one
year's advance, irrevocable, written notice by Executive to the Company pursuant
to which Executive shall specify the date and form of payment of his benefits
under the DCP.

         5. Office and Services. For a one-year period after the Effective Time,
the Company shall furnish Executive with office space, secretarial assistance
and such other reasonable facilities and services commensurate with Executive's
status as former Chief Executive Officer of CNB.

         6. Expenses. The Company shall pay to Executive all legal fees and
expenses (but not taxes, penalties or interest on taxes or penalties) incurred
by Executive (a) in seeking to obtain or enforce any provision of this Agreement
or (b) in connection with any tax audit or proceeding to the extent attributable
to the application of Section 4999 of the Code to any payment or benefit
provided hereunder or under other plans and programs of CNB, the Company or any
of their affiliates. Such payments shall be made within five (5) business days
after delivery of Executive's written requests for payment accompanied with such
evidence of fees and expenses incurred as the Company reasonably may require.

         7. Allocation. Prior to the Effective Time, Executive and the Company
shall agree to a mutually acceptable allocation of the compensation and benefits
provided to Executive hereunder to Executive's covenants hereunder.

         8. Payment Obligations Absolute. The Company's and CNB's obligation
hereunder to pay Executive the amounts and to make the benefit and other
arrangements provided for herein shall be absolute and unconditional and shall
not be affected by any circumstances, including, without limitation, any setoff,
counterclaim, recoupment, defense or other right which CNB or the Company or any
of their affiliates may have against him or anyone else. Except as provided in
Section 7 of this Agreement, all amounts payable by the Company hereunder shall
be paid without notice or demand. Each and every payment made hereunder by the
Company shall be final, and the Company will not seek to recover all or any part
of such payment from Executive, or from whomsoever may be entitled thereto, for
any reason whatsoever.

         9. Successors. In addition to any obligations imposed by law upon any
successor to the Company, the Company shall be obligated to require any
successor (whether direct or indirect and whether by purchase, merger,
consolidation, operation of law or otherwise) to all or substantially all of the
business, property and/or assets of the Company to expressly assume and agree to
perform this Agreement in the same manner and to the same extent that the
Company would be required to perform it if no such succession had taken place.
In the event of such a succession, references to the "Company" herein shall
thereafter be deemed to include such successor. Failure of the Company to obtain
such assumption and agreement prior to the effectiveness of any such succession
shall be a breach of this Agreement.

         10. Severability. The provisions of this Agreement shall be regarded as
divisible, and if any of said provisions or any part hereof are declared invalid
or unenforceable by a court of competent jurisdiction, the validity and
enforceability of the remainder of such provisions or parts hereof and the
applicability thereof shall not be affected thereby.

         11. Entire Agreement. This Agreement constitutes the entire agreement
of CNB, the Company and Executive with respect to the subject matter of this
agreement. No agreements or representations, oral or otherwise, express or
implied, with respect to the subject matter of this Agreement have been made by
either party which are not expressly set forth in this Agreement.

         12. Amendment. This Agreement may not be amended or modified at any
time except by written instrument executed by the Company, Executive and, if
prior to the Effective Time, CNB.

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         13. Taxes. The Company shall be entitled to withhold from amounts to be
paid hereunder any federal, state or local withholding or other taxes or charges
which it is from time-to-time required to withhold.

         14. Governing Law. This Agreement and the rights and obligations
hereunder shall be governed by and construed in accordance with the laws of the
State of New York without regard to the conflicts of laws principles thereof.

         15. Notice. Notices given pursuant to this Agreement shall be in
writing and shall be deemed given when actually received by Executive or
actually received by the Company's or CNB's Secretary, as the case may be. If
mailed, such notices shall be mailed by United States registered or certified
mail, return receipt requested, addressee only, postage prepaid, if to the
Company, to the Secretary of the Company at its headquarters (currently located
at 52 South Broad Street, Norwich, NY 13815), if to CNB, to the Secretary of CNB
at its headquarters (currently located at 24 Church Street, Canajoharie, NY
13317), or if to Executive, at the address set forth below Executive's signature
to this Agreement, or to such other address as the party to be notified shall
have theretofore given to the other party in writing.

         16. No Waiver. No waiver by either party at any time of any breach by
the other party of, or compliance with, any condition or provision of this
Agreement to be performed by the other party shall be deemed a waiver of similar
or dissimilar provisions or conditions at the same time or any prior or
subsequent time.

         17. Headings. The headings herein contained are for reference only and
shall not affect the meaning or interpretation of any provision of this
Agreement.

         18. Counterparts. This Agreement may be executed in counterparts, all
of which shall be considered the same hereunder.


         19. Termination. This Agreement shall terminate in the event that the
Merger Agreement terminates in accordance with Section 12 thereof.


         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
day and year first written above.


NBT Bancorp Inc.

By:   /s/ Daryl R. Forsythe                 /s/ Donald L. Brass
      ---------------------------------     ------------------------------------
      Daryl R. Forsythe                     Donald L. Brass
      President and Chief Executive         841 Greenthorne Blvd.
         Officer                            Schenectady, NY 12303


CNB Financial Corp.

By:   /s/ Peter J. Corso
      Peter J. Corso
      Title Executive Vice President and
         Chief Financial Officer

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