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                                                                     EXHIBIT 4.8

                                   $16,000,000

                            Floating Rate MMCapS(SM)

                         TBC CAPITAL STATUTORY TRUST III

                               PLACEMENT AGREEMENT

                                                              New York, New York
                                                                   June 28, 2001

SANDLER O'NEILL & PARTNERS, L.P.
Two World Trade Center
New York, New York 10048

Ladies and Gentlemen:

         TBC Capital Statutory Trust III (the "Trust"), a statutory business
trust organized under the Delaware Business Trust Act, 12 Del. C. ss. 3801 et
seq. (the "Delaware Act"), and The Banc Corporation, a Delaware corporation (the
"Company" and together with the Trust, the "Offerors"), confirm their agreement
(the "Agreement") with Sandler O'Neill & Partners, L.P., as agent of the
Offerors (the "Placement Agent"), with respect to the issue and sale by the
Trust and the placement by the Placement Agent of $16,000,000 Floating Rate
MMCapS(SM) (liquidation amount of $1,000 per security) of the Trust bearing a
variable distribution rate per annum, reset semi-annually, equal to LIBOR (as
defined in the Indenture) plus 3.75% (the "Capital Securities"). The Capital
Securities will be guaranteed by the Company to the extent provided in the
Guarantee Agreement, to be dated as of the Closing Time (as defined in Section 2
hereof) (the "Guarantee Agreement"), between the Company and The Bank of New
York, as trustee (the "Guarantee Trustee"), with respect to distributions and
payments upon liquidation, redemption and otherwise.

         The entire proceeds from the sale of the Capital Securities will be
combined with the entire proceeds from the sale by the Trust to the Company of
its common securities (the "Common Securities"), and will be used by the Trust
to purchase $16,495,000 aggregate principal amount of Floating Rate Junior
Subordinated Deferrable Interest Debt Securities due July 25, 2031 (the
"Subordinated Debt Securities") issued by the Company. The Capital Securities
and the Common Securities will be issued pursuant to the Amended and Restated
Declaration of Trust, to be dated as of the Closing Time (the "Declaration"),
among the Company, as sponsor, the Administrators named therein (the
"Administrators"), The Bank of New York, as institutional trustee (the
"Institutional Trustee"), The Bank of New York, as Delaware trustee (the
"Delaware Trustee") and the holders, from time to time, of undivided beneficial
interests in the assets of the Trust. The Subordinated Debt Securities will be
issued pursuant to the Indenture, to be dated as of the Closing Time (the
"Indenture"), between the Company and The Bank of New York, as indenture Trustee
(the "Indenture Trustee"). The



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Indenture, the Guarantee Agreement, the Declaration, this Agreement and the
Subscription Agreement (as defined in Section 2(a) hereof) are hereinafter
referred to collectively as the "Operative Documents."

         Section 1.        Representations and Warranties.

         (a)      The Trust and the Company, jointly and severally, represent
and warrant to the Placement Agent and the Purchaser (as defined in Section 2(a)
hereof) of Capital Securities as of the date hereof and as of the Closing Time,
and agree with the Placement Agent and the Purchaser, as follows:

                  (i)      Similar Offerings. The Offerors have not, directly or
         indirectly, solicited any offer to buy or offered to sell, and will
         not, directly or indirectly, solicit any offer to buy or offer to sell,
         in the United States or to any United States citizen or resident, any
         security which is or would be integrated with the sale of the Capital
         Securities in a manner that would require the Capital Securities to be
         registered under the Securities Act of 1933, as amended (the "Act").

                  (ii)     Incorporated Documents. The documents of the Company
         filed with the Securities and Exchange Commission (the "Commission") in
         accordance with the Securities Exchange Act of 1934, as amended (the
         "1934 Act"), from and including the commencement of the fiscal year
         covered by the Company's most recent Annual Report on Form 10-K, at the
         time they were or hereafter are filed by the Company with the
         Commission (collectively, the "1934 Act Reports"), complied and will
         comply in all material respects with the requirements of the 1934 Act
         and the rules and regulations of the Commission thereunder (the "1934
         Act Regulations"), and, at the date of this Agreement and at the
         Closing Time, do not and will not include an untrue statement of a
         material fact or omit to state a material fact required to be stated
         therein or necessary to make the statements therein, in the light of
         the circumstances under which they were made, not misleading; and other
         than such instruments, agreements, contracts and other documents as are
         filed as exhibits to the Company's annual report on Form 10-K,
         quarterly reports on Form 10-Q or current reports on Form 8-K, there
         are no instruments, agreements, contracts or documents of a character
         described in Item 601 of Regulation S-K promulgated by the Commission
         to which the Company or any of its subsidiaries is a party.

                  (iii)    Independent Accountants. The accountants of the
         Company who certified the financial statements included in the 1934 Act
         Reports are independent public accountants of the Company and its
         subsidiaries within the meaning of the 1933 Act and the rules and
         regulations of the Commission thereunder (the " 1933 Act
         Regulations").

                  (iv)     Financial Statements and Information. The
         consolidated historical financial statements of the Company, together
         with the related schedules and notes, included in the 1934 Act Reports
         present fairly, in all material respects, the respective consolidated
         financial positions of the Company and its consolidated


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         subsidiaries at the respective dates indicated, and the consolidated
         statements of income, changes in stockholders' equity and cash flows of
         the Company and its consolidated subsidiaries for the respective
         periods specified; said financial statements have been prepared in
         conformity with generally accepted accounting principles in the United
         States applied on a consistent basis throughout the periods involved,
         except as disclosed in the notes to such financial statements; the
         supporting schedules, if any, included in the 1934 Act Reports present
         fairly, in all material respects, the information required to be stated
         therein and any pro forma financial statements and the related notes
         thereto included in the 1934 Act Reports present fairly the information
         shown therein, have been prepared in accordance with the Commission's
         rules and guidelines with respect to pro forma financial statements and
         have been properly compiled on the bases described therein, and the
         assumptions used in the preparation thereof are reasonable and the
         adjustments used therein are appropriate to give effect to the
         transactions and circumstances referred to therein.

                  (v)      No Material Adverse Change. Since the respective
         dates as of which information is given in the 1934 Act Reports, there
         has not been (A) any material adverse change in the condition,
         financial, regulatory or otherwise, or in the earnings, business
         affairs or business prospects of the Trust or of the Company and its
         subsidiaries considered as one enterprise, whether or not arising in
         the ordinary course of business (a "Material Adverse Effect") or (B)
         any dividend or distribution of any kind declared, paid or made by the
         Company on any class of its capital stock other than regular quarterly
         dividends on the Company's common stock.

                  (vi)     Regulatory Enforcement Matters. Neither the Company
         or any of its subsidiaries is subject or is party to, or has received
         any notice or advice that any of them may become subject or party to,
         any investigation with respect to, any cease-and-desist order,
         agreement, consent agreement, memorandum of understanding or other
         regulatory enforcement action, proceeding or order with or by, or is a
         party to any commitment letter or similar undertaking to, or is subject
         to any directive by, or has been, a recipient of any supervisory letter
         from, or has adopted any board resolutions at the request of, any
         Regulatory Agency (as defined below) that currently restricts in any
         material respect the conduct of their business or that in any material
         manner relates to their capital adequacy, their credit policies, their
         management or their business (each, a "Regulatory Agreement"), nor has
         the Company or any of its subsidiaries been advised by any Regulatory
         Agency that it is considering issuing or requesting any such Regulatory
         Agreement; and there is no unresolved violation, criticism or exception
         by any Regulatory Agency with respect to any report or statement
         relating to any examinations of the Company or any of its subsidiaries
         which, in the reasonable judgment of the Company, is expected to result
         in a Material Adverse Effect. As used herein, the term "Regulatory
         Agency" means any federal or state agency charged with the supervision
         or regulation of depositary institutions or holding companies of
         depositary institutions, or engaged in the insurance of depositary
         institution deposits, or any court, administrative agency or


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         commission or other governmental agency, authority or instrumentality
         having supervisory or regulatory authority with respect to the Company
         or any of its subsidiaries.

                  (vii)    No Undisclosed Liabilities. Neither the Company nor
         any of its subsidiaries has any material liability, whether known or
         unknown, whether asserted or unasserted, whether absolute or
         contingent, whether accrued or unaccrued, whether liquidated or
         unliquidated, and whether due or to become due, including any liability
         for taxes (and there is no past or present fact, situation,
         circumstance, condition or other basis for any present or future
         action, suit, proceeding, hearing, charge, complaint, claim or demand
         against the Company or its subsidiaries giving rise to any such
         liability), except (i) for liabilities set forth in the financial
         statements referred to in section 1 (a)(iv) above; (ii) normal
         fluctuations in the amount of the liabilities referred to in clause (i)
         above occurring in the ordinary course of business of the Company and
         all of its subsidiaries since the date of the most recent balance sheet
         included in such financial statements; and (iii) except as set forth in
         Schedule 1 (a)(vii).

                  (viii)   Good Standing of the Company. The Company has been
         duly organized and is validly existing as a corporation in good
         standing under the laws of the State of Delaware and has full power and
         authority under such laws to own, lease and operate its properties and
         to conduct its business and to enter into and perform its obligations
         under each of the Operative Documents to which it is a party; and the
         Company is duly registered as a financial holding company under the
         Gramm-Leach-Bliley Act.

                  (ix)     Good Standing of the Subsidiaries. Each "significant
         subsidiary" (as defined in Rule 1-02 of Regulation S-X) of the Company
         (a "Significant Subsidiary") has been duly organized and is validly
         existing as an entity in good standing under the laws of the
         jurisdiction in which it is chartered and has full power and authority
         under such laws to own, lease and operate its properties and to conduct
         its current and contemplated business; and the deposit accounts of each
         of the Company's subsidiary banks are insured up to the applicable
         limits by the Bank Insurance Fund of the Federal Deposit Insurance
         Corporation (the "FDIC") to the fullest extent permitted by law and the
         rules and regulations of the FDIC, and no proceeding for the revocation
         or termination of such insurance is pending or, to the knowledge of the
         Company, threatened.

                  (x)      Foreign Qualifications. The Company and its
         subsidiaries are each duly qualified as a foreign corporation to
         transact business and are each in good standing in each jurisdiction in
         which such qualification is required, whether by reason of the
         ownership or leasing of property or the conduct of business, except
         where the failure to so qualify or be in good standing, in the
         reasonable judgment of the Company, is not expected to result in a
         Material Adverse Effect.

                  (xi)     Capital Stock Duly Authorized and Validly Issued. All
         of the issued and outstanding capital stock of the Company has been
         duly authorized and


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         validly issued and is fully paid and nonassessable; except as set forth
         in Schedule I(a)(xi) all of the issued and outstanding capital stock of
         each subsidiary of the Company has been duly authorized and validly
         issued, is fully paid and nonassessable and is owned by the Company,
         directly or through subsidiaries, free and clear of any security
         interest, mortgage, pledge, lien, encumbrance, claim or equitable
         right; and none of the issued and outstanding capital stock of the
         Company or its Significant Subsidiaries was issued in violation of any
         preemptive or similar rights arising by operation of law, under the
         charter, by-laws or code of regulations of the Company or any of its
         Significant Subsidiaries or under any agreement to which the Company or
         any of its Significant Subsidiaries is a party.

                  (xii)    Good Standing of the Trust. The Trust has been duly
         created and is validly existing in good standing as a business trust
         under the Delaware Act with the power and authority to own property and
         to conduct its business as provided in the Declaration, to enter into
         and perform its obligations under the Operative Documents to which it
         is a party, as applicable, and to issue the Capital Securities and the
         Common Securities; the Trust is not a party to or otherwise bound by
         any agreement other than the Operative Documents to which it is a
         party; and the Trust is, and will be, under current law, classified for
         United States federal income tax purposes as a grantor trust and not as
         an association taxable as a corporation.

                  (xiii)   Authorization of Common Securities. At the Closing
         Time, the Common Securities will have been duly authorized for issuance
         by the Trust pursuant to the Declaration and, when duly issued and
         executed in accordance with the Declaration and delivered by the Trust
         to the Company against payment therefor in accordance with the
         subscription agreement therefor, will be validly issued and fully paid
         and nonassessable undivided common beneficial ownership interests in
         the assets of the Trust; the issuance of the Common Securities is not
         subject to preemptive or other similar rights; and at the Closing Time,
         all of the issued and outstanding Common Securities of the Trust will
         be owned directly by the Company, free and clear of any security
         interest, mortgage, pledge, lien, encumbrance, claim or equitable
         right.

                  (xiv)    Authorization of Capital Securities. At the Closing
         Time, the Capital Securities will have been duly authorized for
         issuance by the Trust pursuant to the Declaration, and when duly
         issued, executed and authenticated in accordance with the Declaration
         and delivered by the Trust against payment therefor as provided herein
         and in the Subscription Agreement, will be validly issued and fully
         paid and nonassessable undivided preferred beneficial ownership
         interests in the assets of the Trust; the issuance of the Capital
         Securities will not be subject to preemptive or other similar rights;
         and the Capital Securities will be in the form contemplated by, and
         entitled to the benefits of, the Declaration.

                  (xv)     Authorization of Agreement. This Agreement has been
         duly authorized, executed and delivered by each of the Offerors.


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                  (xvi)    Authorization of Declaration. The Declaration has
         been duly authorized by the Company and, at the Closing Time, will have
         been duly executed and delivered by the Company and the Administrators,
         and assuming due authorization, execution and delivery of the
         Declaration by the Institutional Trustee and the Delaware Trustee, the
         Declaration will be, at the Closing Time, a valid, legal and binding
         agreement of the Company, enforceable against the Company in accordance
         with its terms, except to the extent that enforceability may be limited
         by (a) bankruptcy, insolvency, reorganization, moratorium, fraudulent
         conveyance or other similar laws now or hereafter in effect relating to
         creditors' rights generally and (b) general principles of equity
         (regardless of whether enforceability is considered in a proceeding at
         law or in equity) (collectively, the "Enforceability Exceptions").

                  (xvii)   Authorization of Guarantee Agreement. The Guarantee
         Agreement has been duly authorized by the Company; and, at the Closing
         Time, the Guarantee Agreement will have been duly executed and
         delivered by the Company and will constitute a valid, legal and binding
         agreement of the Company, enforceable against the Company in accordance
         with its terms, except to the extent that enforceability may be limited
         by the Enforceability Exceptions.

                  (xviii)  Authorization of Indenture. The Indenture has been
         duly authorized by the Company and, at the Closing Time, will have been
         duly executed and delivered by the Company and will constitute a valid,
         legal and binding agreement of the Company, enforceable against the
         Company in accordance with its terms, except to the extent that
         enforceability may be limited by the Enforceability Exceptions.

                  (xix)    Authorization of Subordinated Debt Securities. The
         Subordinated Debt Securities have been duly authorized by the Company;
         at the Closing Time, the Subordinated Debt Securities will have been
         duly executed by the Company and, when authenticated in the manner
         provided for in the Indenture and delivered by the Company to the Trust
         against payment therefor as contemplated in the subscription agreement
         therefor, will constitute valid, legal and binding obligations of the
         Company, enforceable against the Company in accordance with their
         terms, except to the extent that enforceability may be limited by the
         Enforceability Exceptions; the Subordinated Debt Securities will be in
         the form contemplated by, and entitled to the benefits of, the
         Indenture; and the Company has no present intention to exercise its
         option to defer payments of interest on the Subordinated Debt
         Securities as provided in the Indenture.

                  (xx)     Authorization of Administrators. Each of the
         Administrators of the Trust is an officer or employee of the Company
         and has been duly authorized by the Company to execute and deliver the
         Declaration.

                  (xxi)    Not an Investment Company. Neither the Trust nor the
         Company is, and immediately following consummation of the transactions
         contemplated hereby and the application of the net proceeds therefrom
         neither the Trust nor the


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         Company will be, an "investment company" required to be registered
         under the Investment Company Act of 1940, as amended (the "1940 Act").

                  (xxii)   Absence of Defaults and Conflicts. The Trust is not
         in violation of the trust certificate of the Trust filed with the State
         of Delaware (the "Trust Certificate") or the Declaration, and neither
         the Company nor any of its Significant Subsidiaries is in violation of
         its charter, by-laws or code of regulations; none of the Trust, the
         Company or any subsidiary of the Company is in default in the
         performance or observance of any obligation, agreement, covenant or
         condition contained in any contract, indenture, mortgage, deed of
         trust, loan or credit agreement, note, lease or other agreement or
         instrument to which it is a party or by which it or any of them may be
         bound or to which any of its properties or assets is subject
         (collectively, "Agreements and Instruments"), except for such defaults
         under Agreements and Instruments that, in the reasonable judgment of
         the Company, are not expected to result in a Material Adverse Effect;
         and the execution, delivery and performance of the Operative Documents
         by the Trust or the Company, as the case may be, the issuance, sale and
         delivery of the Capital Securities and the Subordinated Debt
         Securities, the consummation of the transactions contemplated by the
         Operative Documents, and compliance by the Offerors with the terms of
         the Operative Documents to which they are a party have been duly
         authorized by all necessary corporate action on the part of the Company
         and, at the Closing Time, will have been duly authorized by all
         necessary action on the part of the Trust, and do not and will not,
         whether with or without the giving of notice or passage of time or
         both, violate, conflict with or constitute a breach of, or default or
         Repayment Event (as defined below) under, or result in the creation or
         imposition of any, security interest, mortgage, pledge, lien, charge,
         encumbrance, claim or equitable right upon any properties or assets of
         the Trust, the Company or any of its Significant Subsidiaries pursuant
         to, any of the Agreements and Instruments, nor will such action result
         in any violation of the provisions of the charter, by-laws or code of
         regulations of the Company or any of its Significant Subsidiaries or
         the Declaration or the Trust Certificate, or violation by the Company
         or any of its Significant Subsidiaries of any applicable law, statute,
         rule, regulation, judgment, order, writ or decree of any government,
         government authority, agency or instrumentality or court, domestic or
         foreign, having jurisdiction over the Trust or the Company or any of
         its Significant Subsidiaries or their respective properties or assets
         (collectively, "Governmental Entities"). As used herein, a "Repayment
         Event" means any event or condition which gives the holder of any note,
         debenture or other evidence of indebtedness (or any person acting on
         such holder's behalf) the right to require the repurchase, redemption
         or repayment of all or a portion of such indebtedness by the Trust or
         the Company or any of its Significant Subsidiaries prior to its
         scheduled maturity.

                  (xxiii)  Absence of Labor Dispute. No labor dispute with the
         employees of the Company or any of its subsidiaries exists or, to the
         knowledge of the executive officers of the Company, is imminent, which,
         in the reasonable judgment of the Company, is expected to result in a
         Material Adverse Effect.


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                  (xxiv)   Absence of Proceedings. Except as set forth in
         Schedule 1 (a)(vii), there is no action, suit, proceeding, inquiry or
         investigation before or brought by any Governmental Entity, now
         pending, or, to the knowledge of the Trust or the Company, threatened,
         against or affecting the Trust or the Company or any of its
         subsidiaries, which, in the reasonable judgment of the Trust or the
         Company, is expected to result in a Material Adverse Effect or
         materially and adversely affect the consummation of the transactions
         contemplated by the Operative Documents or the performance by the Trust
         or the Company of its obligations hereunder or thereunder; and the
         aggregate of all pending legal or governmental proceedings to which the
         Trust or the Company or any of its subsidiaries is a party or of which
         any of their respective properties or assets is the subject, including
         ordinary routine litigation incidental to the business, are not, in the
         reasonable judgment of the Company or the Trust, expected to result in
         a Material Adverse Effect.

                  (xxv)    Absence of Further Requirements. No filing with, or
         authorization, approval, consent, license, order, registration,
         qualification or decree of, any Governmental Entity, other than those
         that have been made or obtained, is necessary or required for the
         performance by the Trust or the Company of their obligations under the
         Operative Documents, as applicable, or the consummation by the Trust
         and the Company of the transactions contemplated by the Operative
         Documents.

                  (xxvi)   Possession of Licenses and Permits. Each of the
         Trust, the Company and the subsidiaries of the Company possesses such
         permits, licenses, approvals, consents and other authorizations
         (collectively, "Governmental Licenses") issued by the appropriate
         Governmental Entities necessary to conduct the business now operated by
         them that is material to the Trust or the Company and its subsidiaries
         considered as one enterprise; each of the Trust, the Company and the
         subsidiaries of the Company is in compliance with the terms and
         conditions of all of its Governmental Licenses, except where the
         failure so to comply, in the reasonable judgment of the Company, is not
         expected to, singularly or in the aggregate, have a Material Adverse
         Effect-, all of the Governmental Licenses are valid and in full force
         and effect, except when the invalidity of such Governmental Licenses or
         the failure of such Governmental Licenses to be in full force and
         effect, in the reasonable judgment of the Company, is not expected to
         have a Material Adverse Effect; and none of the Trust, the Company or
         any subsidiary of the Company has received any notice of proceedings
         relating to the revocation or modification of any such Governmental
         Licenses which, singularly or in the aggregate, in the reasonable
         judgment of the Company or the Trust, is expected to result in a
         Material Adverse Effect.

                  (xxvii)  Title to Property. Each of the Trust, the Company and
         the subsidiaries of the Company has good and marketable title to all of
         their respective real and personal properties, in each case free and
         clear of all liens, encumbrances and defects, except such as, in the
         reasonable judgment of the Trust or the Company, singularly or in the
         aggregate, are not expected to result in a Material Adverse Effect; and
         all of the leases and subleases under which the


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         Trust, the Company or any subsidiary of the Company holds properties,
         are in full force and effect, except when the failure of such leases
         and subleases to be in full force and effect, in the reasonable
         judgment of the Company, singularly or in the aggregate, is not
         expected to have a Material Adverse Effect, and none of the Trust, the
         Company or any subsidiary of the Company has any notice of any claim of
         any sort that has been asserted by anyone adverse to the rights of the
         Trust, the Company or any subsidiary of the Company under any of the
         leases or subleases under which the Trust, the Company or any
         subsidiary of the Company holds properties, or affecting or questioning
         the rights of such entity to the continued possession of the leased or
         subleased premises under any such lease or sublease, except when such
         claim, in the reasonable judgment of the Company, singularly or in the
         aggregate, is not expected to have a Material Adverse Effect.

                  (xxviii) Stabilization. The Company has not taken and will not
         take, directly or indirectly, any action designed to, or that might be
         reasonably expected to, cause or result in stabilization or
         manipulation of the price of the Capital Securities.

                  (xxix)   No General Solicitation. Neither the Trust or the
         Company nor any of their Affiliates (as defined in Rule 501(b) under
         the 1933 Act) or any person acting on its or any of their behalf (other
         than the Placement Agent, as to whom the Offerors make no
         representation) has engaged or will engage, in connection with the
         offering of the Capital Securities, in any form of general solicitation
         or general advertising within the meaning of Rule 502(c) under the 1933
         Act.

                  (xxx)    No Directed Selling Efforts. Neither the Trust or the
         Company nor any of their Affiliates or any person acting on its or any
         of their behalf (other than the Placement Agent, as to whom the
         Offerors make no representation) has engaged or will engage in any
         directed selling efforts within the meaning of Regulation S under the
         1933 Act ("Regulation S") with respect to the offering of the Capital
         Securities.

                  (xxxi)   No Registration. Subject to compliance by the
         Placement Agent with the relevant provisions of Section 6 hereof, it is
         not necessary in connection with the offer, sale and delivery of the
         Capital Securities by the Trust in the manner contemplated by this
         Agreement to register the Capital Securities, the guarantee as
         described in the Guarantee Agreement or the Subordinated Debt
         Securities under the 1933 Act or to qualify the Declaration, the
         Guarantee Agreement or the Indenture under the Trust Indenture Act of
         1939, as amended.

                  (xxxii)  No Integration. Within the period of the preceding
         six months prior to the date hereof, neither the Company or the Trust
         nor any other person acting on behalf of the Company or the Trust has
         offered or sold to any person any Capital Securities, or any securities
         of the same or a similar class as the Capital Securities, other than
         the Capital Securities referred to herein.


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         (b)      Any certificate signed by any Trustee of the Trust or any duly
authorized officer of the Company or any of its subsidiaries and delivered to
you or to counsel for the Placement Agent shall be deemed a representation and
warranty by the Trust or the Company, as the case may be, to the Placement Agent
as to the matters covered thereby.

         Section 2.        Sale and Delivery through Placement Agent; Closing.

         (a)      The Offerors propose to issue and sell the Capital Securities
on July 16, 2001 (or such other time mutually agreed to by the Offerors and the
Placement Agent) (the "Closing Time") to MM Community Funding Ltd, a newly
formed company with limited liability incorporated under the laws of the Cayman
Islands (the "Purchaser"), pursuant to the terms of the Capital Securities
Subscription Agreement, to be entered into on or prior to the Closing Time (the
"Subscription Agreement"), between the Offerors and the Purchaser. The Offerors
agree to execute the Subscription Agreement with the Purchaser and to return the
same to the Placement Agent. In addition, the Offerors agree that the Purchaser
shall be entitled to the benefit of, and to rely on, the provisions of this
Agreement to the extent such provisions address or relate to the Purchaser or
the Capital Securities to be purchased by the Purchaser.

         (b)      The Offerors hereby grant to the Placement Agent the exclusive
right to arrange the placement of the Capital Securities with the Purchaser on
their behalf. The Placement Agent accepts such right and agrees to use its best
efforts, on and prior to the Closing Time, to effect such placement.

         (c)      Deliveries of certificates for the Capital Securities shall be
made by the Trust to or on behalf of the Purchaser at the offices of Cleary,
Gottlieb, Steen & Hamilton in The City of New York, and payment of the purchase
price for the Capital Securities shall be made by the Purchaser to the Trust by
wire transfer of immediately available funds to a bank designated by the Company
contemporaneous with closing at the Closing Time.

         Certificates for the Capital Securities in the aggregate liquidation
amount thereof shall be registered in the name of the Purchaser.

         (d)      As compensation to the Placement Agent for its placement of
the Capital Securities and in view of the fact that the proceeds of the sale of
the Capital Securities will be used to purchase the Subordinated Debt Securities
of the Company, the Company hereby agrees to pay at the Closing Time to the
Placement Agent in immediately available funds a commission of $30.00 per
Capital Security to be delivered by the Trust hereunder at the Closing Time.

         (e)      In performing its duties under this Agreement, the Placement
Agent shall be entitled to rely upon any notice, signature or writing which the
Placement Agent shall in good faith believe to be genuine and to be signed or
presented by a proper party or parties. The Placement Agent may rely upon any
opinions or certificates or other documents delivered by the Offerors or their
counsel or designees either to it or the Purchaser. In addition, in connection
with the performance of its duties under this Agreement, the Placement Agent
shall not be liable for any error of judgment or any action taken or omitted to
be taken unless it was grossly negligent or engaged in willful misconduct in
connection with such performance or nonperformance. No provision of this
Agreement shall require the Placement Agent to expend or


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<PAGE>   11
risk its own funds or otherwise incur any financial liability on behalf of the
Purchaser in connection with the performance of any of its duties hereunder. The
Placement Agent shall be under no obligation to exercise any of the rights or
powers vested in it by this Agreement.

         Section 3.        Notice of Material Events. The Offerors covenant
with the Placement Agent and the Purchaser that prior to the completion of the
initial placement of the Capital Securities through the Placement Agent, the
Offerors will immediately notify the Placement Agent, and confirm such notice in
writing, of any event or development that, in the reasonable judgment of the
Company, is expected to result in a Material Adverse Effect.

         Section 4.        Payment of Expenses. Whether or not this Agreement or
the Subscription Agreement is terminated or the sale of the Capital Securities
is consummated, the Company, as borrower under the Subordinated Debt Securities,
will pay all expenses incident to the performance of its obligations under this
Agreement, including (i) the preparation, issuance and delivery of the
certificates for the Capital Securities and Subordinated Debt Securities, (ii)
the fees and disbursements of the Company's counsel, accountants and other
advisors, and (iii) the fees and expenses of any trustee appointed under any of
the Operative Documents, including the fees and disbursements of counsel for
such trustees.

         Section 5.        Conditions of Placement Agent's Obligations. The
obligations of the Placement Agent and the Purchaser at the Closing Time are
subject to the accuracy of the representations and warranties of the Offerors
contained in Section 1 hereof or in certificates of any Administrator of the
Trust or any officer of the Company or any of its subsidiaries delivered
pursuant to the provisions hereof, to the performance by the Offerors of their
obligations hereunder, and to the following further conditions:

         (a)      Opinion of Counsel for Offerors. At the Closing Time, the
Placement Agent shall have received the favorable opinion, dated as of the
Closing Time, of Thacher Proffitt & Wood, special counsel to the Offerors, in
substantially the form set out in Annex A hereto, in form and substance
reasonably satisfactory to counsel for the Placement Agent. Such counsel may
state that, insofar as such opinion involves factual matters, they have relied,
to the extent they deem proper, upon certificates of Administrators of the
Trust, officers of the Company or any of its subsidiaries and public officials.

         (b)      Opinion of Special Delaware Counsel for the Trust. At the
Closing Time, the Placement Agent shall have received the favorable opinion,
dated as of the Closing Time, of Richards, Layton & Finger, P.A., special
Delaware counsel the Trust, in substantially the form set out in Annex B hereto,
in form and substance reasonably satisfactory to counsel for the Placement
Agent.

         (c)      Opinion of Special Tax Counsel for the Offerors. At the
Closing Time, the Placement Agent shall have received an opinion, dated as of
the Closing Time, of Thacher Proffitt & Wood, special tax counsel to the
Offerors that (i) the Trust will be classified for United States federal income
tax purposes as a grantor trust and not as an association taxable as a
corporation and (ii) the Subordinated Debt Securities will constitute
indebtedness of the Company for United States federal income tax purposes, in
substantially the form set out in Annex C hereto. Such opinion may be
conditioned on, among other things, the initial and


                                       11
<PAGE>   12

continuing accuracy of the facts, financial and other information, covenants and
representations set forth in certificates of officers of the Company and other
documents deemed necessary for such opinion.

         (d)      Opinion of Counsel to the Guarantee Trustee, the Institutional
Trustee and the Indenture Trustee. At the Closing Time, the Placement Agent
shall have received the favorable opinion, dated as of the Closing Time, of
White & Case, LLP, counsel for the Guarantee Trustee, the Institutional Trustee
and the Indenture Trustee, in substantially the form set out in Annex D hereto,
in form and substance reasonably satisfactory to counsel for the Placement
Agent.

         (e)      Opinion of Counsel for the Delaware Trustee. At the Closing
Time, the Placement Agent shall have received the favorable opinion, dated as of
the Closing Time, of Richards, Layton & Finger, P.A., counsel for the Delaware
Trustee, in substantially the form set out in Annex E hereto, in form and
substance reasonably satisfactory to counsel for the Placement Agent.

         (f)      Certificates. At the Closing Time, there shall not have been,
since the date hereof or since the respective dates as of which information is
given in the 1934 Act Reports, any Material Adverse Effect, and the Placement
Agent shall have received a certificate of the Chairman, the Chief Executive
Officer, the President, any Executive Vice President or any Vice President of
the Company and of the Chief Financial Officer or Chief Accounting Officer of
the Company and a certificate of an Administrator of the Trust, dated as of the
Closing Time, to the effect that (i) there has been no such Material Adverse
Effect, (ii) the representations and warranties in Section 1 hereof were true
and correct when made and are true and correct with the same force and effect as
though expressly made at and as of the Closing Time, and (iii) the Offerors have
complied with all agreements and satisfied all conditions on their part to be
performed or satisfied at or prior to the Closing Time.

         (g)      Maintenance of Ratings. Between the date of this Agreement and
the Closing Time, there shall not have occurred a downgrading in or withdrawal
of the rating assigned to the Company's debt securities or preferred stock by
any nationally recognized statistical rating organization, and no such
organization shall have publicly announced that it has under surveillance or
review its rating of the Company's debt securities or preferred stock.

         (h)      Sale of Securities. The Purchaser shall have sold securities
issued by it in such an amount that the net proceeds therefrom shall be
available at the Closing Time and shall be sufficient to purchase the Capital
Securities and all other capital securities contemplated in agreements similar
to this Agreement and the Subscription Agreement.

         (i)      Additional Documents. At the Closing Time, the Placement Agent
and the Purchaser shall have been furnished such documents and opinions as they
may reasonably request in connection with issue, sale and placement of the
Capital Securities; and all proceedings taken by the Offerors in connection with
the issuance, sale and placement of the Capital Securities shall be satisfactory
in form and substance to the Placement Agent and the Purchaser.


                                       12
<PAGE>   13

         (j)      Termination of Agreement. If any condition specified in this
Section shall not have been fulfilled when and as required to be fulfilled, this
Agreement may be terminated by the Placement Agent by notice to the Offerors at
any time at or prior to the Closing Time, and such termination shall be without
liability of any party to any other party except as provided in Section 4 hereof
and except that Sections 7 and 8 hereof shall survive any such termination and
remain in full force and effect.

         Section 6.        Offers and Sales of the Capital Securities.

         (a)      Offer and Sale Procedures. The Placement Agent and the
Offerors hereby establish and agree to observe the following provisions with
respect to the offer, issue, sale and placement of the Capital Securities:

                  (i)      Offers and Sales only to the Purchaser. Offers and
         sales of the Capital Securities will be made in the United States or
         pursuant to Regulation S outside the United States only to the
         Purchaser in a transaction not requiring registration under the 193 3
         Act.

                  (ii)     No General Solicitation. No general solicitation or
         general advertising (within the meaning of Rule 502(c) under the 1933
         Act) will be used in connection with the offering of the Capital
         Securities.

                  (iii)    No Directed Selling Efforts. No directed selling
         efforts (within the meaning of Regulation S) will be used with respect
         to the offering of the Capital Securities.

                  (iv)     Purchaser Notification. Prior to or contemporaneously
         with the purchase of the Capital Securities by the Purchaser, the
         Placement Agent will take reasonable steps to inform the Purchaser that
         the Capital Securities (A) have not been and will not be registered
         under the 1933 Act, (B) are being sold to them without registration
         under the 1933 Act in accordance with an exemption from registration
         under the 1933 Act and (C) may not be offered, sold or otherwise
         transferred except (1) to the Company or (2) in accordance with (x)
         Rule 144A to a person whom the seller reasonably believes is a
         Qualified Institutional Buyer (as defined in Rule 144A under the
         Securities Act ("Rule 144A")) that is purchasing such Securities for
         its own account or for the account of a Qualified Institutional Buyer
         to whom notice is given that the offer, sale or transfer is being made
         in reliance on Rule 144A, (y) Regulation S to a non-U.S. person in an
         offshore transaction or (z) any other available exemption from
         registration under the 1933 Act (including the exemption provided by
         Rule 144).

         (b)      Covenants of the Offerors. Each of the Offerors, jointly and
severally, covenant with the Placement Agent and the Purchaser as follows:

                  (i)      Due Diligence. In connection with the initial
         placement of the Capital Securities, the Offerors agree that, prior to
         any offer or sale of the Capital Securities through the Placement
         Agent, the Placement Agent and the Purchaser shall have the right to
         make reasonable inquiries into the business of the Trust, the


                                       13
<PAGE>   14

         Company and the subsidiaries of the Company. The Offerors also agree to
         provide answers to the Placement Agent and the Purchaser, if requested,
         concerning the Trust, the Company and the subsidiaries of the Company
         (to the extent that such information is available or can be acquired
         and made available without unreasonable effort or expense and to the
         extent the provision thereof is not prohibited by applicable law) and
         the terms and conditions of the offering of the Capital Securities and
         the Subordinated Debt Securities.

                  (ii)     Integration. The Offerors agree that they will not,
         and will cause their Affiliates not to, make any offer or sale of
         securities of the Offerors of any class if, as a result of the doctrine
         of "integration" referred to in Rule 502 under the 1933 Act, such offer
         or sale would render invalid the exemption from the registration
         requirements of the 1933 Act provided by Section 4(2) thereof or by
         Rule 144A or otherwise.

                  (iii)    Restriction on Repurchases. Until the expiration of
         two (2) years (or such shorter period as may hereafter be referred to
         in Rule 144(k) (or similar successor rule)) after the original issuance
         of the Capital Securities, the Offerors will not, and will cause their
         Affiliates not to, purchase or agree to purchase or otherwise acquire
         any Capital Securities which are "restricted securities" (as such term
         is defined under Rule 144(a)(3) under the 1933 Act), whether as
         beneficial owner or otherwise unless, immediately upon any such
         purchase, the Offerors or any Affiliate shall submit such Capital
         Securities to the Institutional Trustee for cancellation.

         Section 7.        Indemnification.

         (a)      Indemnification of the Placement Agent and the Purchaser. The
Offerors agree, jointly and severally, to indemnify and hold harmless: (x) the
Placement Agent and the Purchaser, (y) each person, if any, who controls (within
the meaning of Section 15 of the 1933 Act or Section 20 of the 1934 Act the
Placement Agent or the Purchaser (each such person, a "controlling person") and
(z) the respective partners, directors, officers, employees and agents of the
Placement Agent and the Purchaser or any such controlling person, as follows:

                  (i)      against any and all loss, liability, claim, damage
         and expense whatsoever, as incurred, relating to or arising out of, or
         based upon, in whole or in part, (A) any untrue statement or alleged
         untrue statement of a material fact included in the 1934 Act Reports,
         or the omission or alleged omission therefrom of a material fact
         necessary in order to make the statements therein, in the light of the
         circumstances under which they were made, not misleading; (B) any
         untrue statement or alleged untrue statement of material fact contained
         in any information (whether written or oral) or documents executed in
         favor of or furnished or made available to the Placement Agent or the
         Purchaser by the Offerors; (C) any omission or alleged omission to
         state in any information (whether written or oral) or documents
         executed in favor of or furnished or made available to the Placement
         Agent or the Purchaser by the Offerors a material fact necessary to
         make the statements therein not misleading; or (D) the breach or


                                       14
<PAGE>   15

         alleged breach of any representation, warranty and agreement of any
         Offeror contained herein or in the Subscription Agreement;

                  (ii)     against any and all loss, liability, claim, damage
         and expense whatsoever, as incurred, to the extent of the aggregate
         amount paid in settlement of any litigation, or any investigation or
         proceeding by any governmental agency or body, commenced or threatened,
         or of any claim whatsoever based upon any such untrue statement or
         omission, or any such alleged untrue statement or omission or breach or
         alleged breach of any such representation, warranty or agreement;
         provided that (subject to Section 7(c) hereof) any such settlement is
         effected with the written consent of the Offerors; and

                  (iii)    against any and all expense whatsoever, as incurred
         (including the fees and disbursements of counsel chosen by the
         Placement Agent), reasonably incurred in investigating, preparing or
         defending against any litigation, or any investigation or proceeding by
         any governmental agency or body, commenced or threatened, or any claim
         whatsoever based upon any such untrue statement or omission, or any
         such alleged untrue statement or omission, or breach or alleged breach
         of any such representation, warranty or agreement, to the extent that
         any such expense is not paid under (i) or (ii) above;

      provided, however, that the Company shall indemnify and hold harmless the
Trust against any and all loss, liability, claim, damage and expense whatsoever,
as incurred, which is due from the Trust pursuant to the foregoing.

         (b)      Actions against Parties; Notification. Each indemnified party
shall give notice as promptly as reasonably practicable to each indemnifying
party of any action commenced against it in respect of which indemnity may be
sought hereunder, but failure to so notify an indemnifying party shall not
relieve such indemnifying party from any liability hereunder to the extent it is
not materially prejudiced as a result thereof, and in any event shall not
relieve it from any liability which it may have otherwise than on account of
this indemnity agreement. Counsel to the indemnified parties shall be selected
by the Placement Agent. An indemnifying party may participate at its own expense
in the defense of any such action; provided, however, that counsel to the
indemnifying party shall not (except with the consent of the indemnified party)
also be counsel to the indemnified party. In no event shall the indemnifying
parties be liable for fees and expenses of more than one counsel (in addition to
any local counsel) separate from their own counsel for all indemnified parties
in connection with any one action or separate but similar or related actions in
the same jurisdiction arising out of the same general allegations or
circumstances. No indemnifying party shall, without the prior written consent of
the indemnified parties, settle or compromise or consent to the entry of any
judgment with respect to any litigation, or any investigation or proceeding by
any governmental agency or body, commenced or threatened, or any claim
whatsoever in respect of which indemnification or contribution could be sought
under this Section 7 or Section 8 hereof (whether or not the indemnified parties
are actual or potential parties thereto), unless such settlement, compromise or
consent (i) includes an unconditional release of each indemnified party from all
liability arising out of such litigation, investigation, proceeding or claim and
(ii)


                                       15
<PAGE>   16

does not include a statement as to or an admission of fault, culpability or a
failure to act by or on behalf of any indemnified party.

         (c)      Settlement without Consent if Failure to Reimburse. If at any
time an indemnified party shall have validly requested an indemnifying party to
reimburse the indemnified party for fees and expenses of counsel, such
indemnifying party agrees that it shall be liable for any settlement of the
nature contemplated by Section 7(a)(ii) effected without its written consent if
(i) such settlement is entered into more than 45 days after receipt by such
indemnifying party of the aforesaid request, (ii) such indemnifying party shall
have received notice of the terms of such settlement at least 30 days prior to
such settlement being entered into and (iii) such indemnifying party shall not
have reimbursed such indemnified party in accordance with such request prior to
the date of such settlement, provided, however, that an indemnifying party shall
not be liable for any such settlement effected without its consent if such
indemnifying party (1) reimburses such indemnified party with respect to those
fees and expenses of counsel that it determines in good faith are reasonable and
(2) provides written notice within ten (10) days after receipt of the request
for reimbursement to the indemnified party substantiating the unpaid balance as
unreasonable, in each case prior to the date of such settlement.

         Section 8.        Contribution. In order to provide for just and
equitable contribution in circumstances under which the indemnification provided
for in Section 7 hereof is for any reason held to be unenforceable by an
indemnified party in respect of any losses, liabilities, claims, damages or
expenses referred to therein, then each indemnifying party shall contribute to
the aggregate amount of such losses, liabilities, claims, damages and expenses
incurred by such indemnified party, as incurred, (i) in such proportion as is
appropriate to reflect the relative benefits received by the Offerors, on the
one hand, and the Placement Agent, on the other hand, from the offering of the
Capital Securities pursuant to this Agreement or (ii) if the allocation provided
by clause (i) is not permitted by applicable law, in such proportion as is
appropriate to reflect not only the relative benefits referred to in clause (i)
above but also the relative fault of the Offerors, on the one hand, and the
Placement Agent, on the other hand, in connection with the statements, omissions
or breaches which resulted in such losses, liabilities, claims, damages or
expenses, as well as any other relevant equitable considerations.

         The relative benefits received by the Offerors, on the one hand, and
the Placement Agent, on the other hand, in connection with the offering of the
Capital Securities pursuant to this Agreement shall be deemed to be in the same
respective proportions as the total net proceeds from the offering of the
Capital Securities pursuant to this Agreement (before deducting expenses)
received by the Offerors and the total commission received by the Placement
Agent bear to the aggregate of such net proceeds and commissions.

         The Offerors and the Placement Agent agree that it would not be just
and equitable if contribution pursuant to this Section 8 were determined by pro
rata allocation or by any other method of allocation which does not take account
of the equitable considerations referred to above in this Section 8. The
aggregate amount of losses, liabilities, claims, damages and expenses incurred
by an indemnified party and referred to above in this Section 8 shall be deemed
to include any legal or other expenses reasonably incurred by such indemnified
party in investigating, preparing or defending against any litigation, or any
investigation or proceeding by


                                       16

<PAGE>   17

any governmental agency or body, commenced or threatened, or any claim
whatsoever based upon any such untrue or alleged untrue statement, omission or
alleged omission or breach or alleged breach.

         Notwithstanding the provisions of this Section 8, the Placement Agent
shall not be required to contribute any amount in excess of the total
commissions received by it.

         No person guilty of fraudulent misrepresentation (within the meaning of
Section 11(f) of the 1933 Act) shall be entitled to contribution from any
person who was not guilty of such fraudulent misrepresentation.

         For purposes of this Section 8, the Purchaser, each person, if any, who
controls the Placement Agent or the Purchaser within the meaning of Section 15
of the 1933 Act or Section 20 of the 1934 Act and the respective partners,
directors, officers, employees and agents of the Placement Agent, the Purchaser
or any such controlling person shall have the same rights to contribution as the
Placement Agent, while each officer and director of the Company, each Trustee of
the Trust and each person, if any, who controls the Company within the meaning
of Section 15 of the 1933 Act or Section 20 of the 1934 Act shall have the same
rights to contribution as the Offerors.

         Section 9.        Representations, Warranties and Agreements to Survive
Delivery. All representations, warranties and agreements contained in this
Agreement or in certificates of officers of the Company or Trustees of the Trust
submitted pursuant hereto shall remain operative and in full force and effect,
and shall survive delivery of the Capital Securities by the Trust.

         Section 10.       Termination of Agreement.

         (a)      Termination; General. The Placement Agent may terminate this
Agreement, by notice to the Offerors, at any time at or prior to the Closing
Time if, since the time of execution of this Agreement or since the respective
dates as of which information is given in the 1934 Act Reports, (i) there has
occurred any Material Adverse Effect, or (ii) there has occurred any material
adverse change in the financial markets in the United States, any outbreak of
hostilities or escalation thereof or any other calamity or crisis, or any change
or development involving political, financial or economic conditions, in each
case the effect of which is such as to make it, in the judgment of the Placement
Agent, impracticable to market the Capital Securities or to enforce contracts
for the sale of the Capital Securities, or (iii) trading in any securities of
the Company has been suspended or limited by the Commission or any national
stock exchange or market on or in which such securities are traded or quoted, or
if trading generally on the American Stock Exchange, the New York Stock Exchange
or the Nasdaq National Market has been suspended or limited, or minimum or
maximum prices for trading have been fixed, or maximum ranges for prices have
been required, by any of said exchanges or by such system or by order of the
Commission, the National Association of Securities Dealers or any other
governmental authority, or (iv) a banking moratorium has been declared by United
States federal, Delaware or New York authorities.


                                       17

<PAGE>   18

         (b)      Liabilities. If this Agreement is terminated pursuant to this
Section, such termination shall be without liability of any party to any other
party except as provided in Section 4 hereof, and provided further that Sections
1, 7 and 8 hereof shall survive such termination and remain in full force and
effect.

         Section 11.       Notices. All notices and other communications
hereunder shall be in writing and shall be deemed to have been duly given if
mailed or transmitted by any standard form of telecommunication. Notices to the
Placement Agent shall be directed to Sandler O'Neill & Partners, L.P., Two World
Trade Center, New York, New York 10048, Attention: Thomas W. Killian, Principal,
with a copy to Cleary, Gottlieb, Steen & Hamilton, 2000 Pennsylvania Avenue,
N.W., Washington, D.C. 20006, Attention: Kenneth L. Bachman, Esq.; and notices
to the Offerors shall be directed to The Banc Corporation, 17 North 20th Street,
Birmingham, Alabama 35203, Attention: James A. Taylor, Jr., with copies to The
Banc Corporation, 17 North 20th Street, Birmingham, Alabama 35203, Attention: F.
Hampton McFadden, Jr., Esq. and Thacher Proffitt & Wood, Two World Trade Center,
New York, New York 10048, Attention: Robert C. Azarow, Esq.

         Section 12.       Parties. This Agreement shall inure to the benefit of
and be binding upon each of the Placement Agent and the Offerors and their
respective successors. Nothing expressed or mentioned in this Agreement is
intended or shall be construed to give any person, firm or corporation, other
than the Placement Agent, the Purchaser and the Offerors, and their respective
successors and the controlling persons and other persons referred to in Sections
1, 7 and 8 hereof and their heirs and legal representatives, any legal or
equitable right, remedy or claim under or in respect of this Agreement or any
provision herein contained. This Agreement and all conditions and provisions
hereof are intended to be for the sole and exclusive benefit of the Placement
Agent, the Purchaser and the Offerors and their respective successors, and said
controlling persons and other persons and their heirs and legal representatives,
and for the benefit of no other person, firm or corporation.

         Section 13.       GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY
AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT
REGARD TO CONFLICT OF LAW PRINCIPLES.

         EACH OF THE TRUST AND THE COMPANY, ON BEHALF OF ITSELF AND ITS
SUBSIDIARIES (INCLUDING, WITHOUT LIMITATION, THE TRUST), HEREBY IRREVOCABLY
SUBMITS TO THE EXCLUSIVE JURISDICTION OF THE FEDERAL AND NEW YORK STATE COURTS
LOCATED IN THE CITY OF NEW YORK IN CONNECTION WITH ANY SUIT, ACTION OR
PROCEEDING RELATED TO THIS AGREEMENT OR ANY OF THE MATTERS CONTEMPLATED HEREBY,
IRREVOCABLY WAIVES ANY DEFENSE OF LACK OF PERSONAL JURISDICTION AND IRREVOCABLY
AGREES THAT ALL CLAIMS IN RESPECT OF ANY SUIT, ACTION OR PROCEEDING MAY BE HEARD
AND DETERMINED IN ANY SUCH COURT. EACH OF THE TRUST AND THE COMPANY, ON BEHALF
OF ITSELF AND ITS SUBSIDIARIES (INCLUDING, WITHOUT LIMITATION, THE TRUST),
IRREVOCABLY WAIVES, TO THE FULLEST EXTENT IT MAY EFFECTIVELY DO SO UNDER
APPLICABLE LAW, ANY OBJECTION WHICH IT MAY NOW OR HEREAFTER HAVE TO THE LAYING
OF VENUE OF ANY SUCH SUIT, ACTION OR PROCEEDING BROUGHT IN ANY SUCH COURT AND
ANY CLAIM THAT ANY SUCH SUIT, ACTION OR PROCEEDING BROUGHT IN ANY SUCH COURT HAS
BEEN BROUGHT IN AN INCONVENIENT FORUM.

         Section 14.       Effect of Headings. The Article and Section headings
herein are for convenience only and shall not affect the construction hereof.


                                       18
<PAGE>   19

         If the foregoing is in accordance with your understanding of our
agreement, please sign and return to the Company a counterpart hereof, whereupon
this instrument, along with all counterparts, will become a binding agreement
among the Placement Agent and the Offerors in accordance with its terms.

                                    Very truly yours,

                                    THE BANC CORPORATION


                                    By: /s/ DAVID R. CARTER
                                       --------------------------------------
                                       Name:  David R. Carter
                                       Title: Executive Vice President & CFO



                                    TBC CAPITAL STATUTORY TRUST III


                                    By: /s/ JAMES A. TAYLOR, JR.
                                       --------------------------------------
                                       Name:  James A. Taylor, Jr.
                                       Title: Administrator



CONFIRMED AND ACCEPTED,
as of the date first above written:

SANDLER O'NEILL & PARTNERS, L.P.

By:    Sandler O'Neill & Partners Corp.,
       the sole general partner


By: /s/ CATHERINE A. LAWTON
   ---------------------------------------
   Name:  Catherine A. Lawton
   Title: Vice President

                                                                             PA
<PAGE>   20
                                                                         ANNEX A


Pursuant to Section 5(a) of the Placement Agreement, counsel to the Company
shall deliver an opinion in substantially the following form:

         1.       The Company is incorporated and is validly existing as a
corporation in good standing under the laws of the State of (STATE OF
INCORPORATION).

         2.       The Company has corporate power and authority to (i) execute
and deliver, and to perform its obligations under, the Operative Documents to
which it is a party and (ii) issue and perform its obligations under the
Subordinated Debt Securities.

         3.       The Company is registered as [a bank holding company under the
Bank Holding Company Act of 1956, as amended][a financial holding company under
the Gramm-Leach-Bliley Act] [as a savings and loan holding company under the
Home Owners' Loan Act of 1933, as amended].

         4.       (i) [The][Each] Bank is validly existing and in good standing
under the laws of the jurisdiction of its organization, and (ii) to the best of
our knowledge, all of the issued and outstanding shares of capital stock of the
Bank are owned of record by the Company, directly or through subsidiaries.

         5.       The deposit accounts of [the) [each] Bank are insured by the
Federal Deposit Insurance Company up to the maximum amount allowable under
applicable law.

         6.       No consent, approval, authorization or order of or filing,
registration or qualification with any Governmental Entity is required in
connection with the execution and delivery by the Company of the Operative
Documents and the consummation of the transactions contemplated thereby except
as have already been obtained or made.

         7.       The Trust has been created and is validly existing and in good
standing as a business trust under the Delaware Business Trust Act.

         8.       Under the Delaware Business Trust Act and the Amended
Declaration, the Trust has the requisite power and authority to (i) own its
current properties and conduct its current business (all as described in the
Amended Declaration), (ii) execute and deliver, and to perform its obligations
under, the Operative Documents to which it is a party, (iii) issue and perform
its obligations under the Capital Securities and the Common Securities and (iv)
purchase and hold the Subordinated Debt Securities.

         9.       Under the Delaware Business Trust Act and the Amended
Declaration, the execution and delivery by the Trust of the Operative Documents
to which it is a party, and the performance by the Trust of its obligations
thereunder, have been duly authorized by the requisite trust action on the part
of the Trust.

         10.      The issuance and sale by the Trust of the Capital Securities
and Common Securities, the execution, delivery and performance by the Trust of
the Operative Documents to which it is a party, the consummation by the Trust of
the transactions contemplated thereby and


                                   Annex A-1
<PAGE>   21

compliance by the Trust with its obligations thereunder are not prohibited by
(i) the Amended Declaration or (ii) any applicable statute, governmental rule or
regulation of the State of Delaware.

         11.      No authorization, approval, consent or order of any Delaware
court or Delaware governmental authority or Delaware agency is required to be
obtained by the Trust solely as a result of the issuance and sale of the Capital
Securities and the Common Securities or the performance by the Trust of its
obligations under the Operative Documents to which it is a party.

         12.      Assuming that the Trust derives no income from or in
connection with sources within the State of Delaware and has no assets,
activities (other than maintaining the Delaware Trustee and the filing of
documents with the Secretary of State of the State of Delaware) or employees in
the State of Delaware, the holders of the Capital Securities (other than those
holders of Capital Securities who reside or are domiciled in the State of
Delaware) will have no liability for income taxes imposed by the State of
Delaware solely as a result of their participation in the Trust, and the Trust
will not be liable for any income tax imposed by the State of Delaware.

         13.      Each of the Placement Agreement and the Capital Securities
Subscription Agreement has been duly authorized, executed and delivered by each
of the Company and the Trust.

         14.      The Amended Declaration has been duly authorized, executed and
delivered by the Company and constitutes a valid and binding agreement of the
Company and the Administrative Trustees, enforceable against each such party in
accordance with its terms.

         15.      The Capital Securities and the Common Securities have been
duly authorized for issuance by the Amended Declaration; and the Capital
Securities, when duly issued, executed and authenticated in the manner provided
for in the Amended Declaration and delivered against payment therefor in
accordance with the Capital Securities Subscription Agreement and the Amended
Declaration, will be validly issued and, subject to the qualifications set forth
in paragraph 16 below, fully paid and nonassessable undivided beneficial
interests in the assets of the Trust and will entitle the holders thereof to the
benefits of the Amended Declaration.

         16.      The holders of the Capital Securities, as beneficial owners of
the Trust, will be entitled to the same limitation of personal liability
extended to stockholders of private corporations for profit organized under the
General Corporation Law of the State of Delaware; it being understood, however,
that the holders of the Capital Securities may be obligated, pursuant to the
Amended Declaration, to provide (i) indemnity and/or security in connection with
and pay taxes or governmental charges arising from transfers or exchanges of
certificates evidencing such capital securities ("Capital Security
Certificates") and the issuance of replacement Capital Security Certificates,
and (ii) security or indemnity in connection with requests of or directions to
the Institutional Trustee to exercise its rights and powers under the Amended
Declaration.


                                    Annex A-2
<PAGE>   22

         17.      Under the Delaware Business Trust Act and the Amended
Declaration, the issuance of the Capital Securities and the Common Securities by
the Trust will not be subject to preemptive rights.

         18.      The Common Securities, when duly issued and executed in
accordance with the Amended Declaration and delivered against payment therefor
in accordance with the Amended Declaration and the Common Securities
Subscription Agreement, will be validly issued undivided beneficial interests in
the assets of the Trust.

         19.      Each of the Operative Documents to which the Trust is a party
(other than the Placement Agreement and the Capital Securities Subscription
Agreement, as to which we have opined in paragraph 13 above) has been duly
authorized, executed and delivered by the Trust and constitutes a valid and
binding agreement of the Trust, enforceable against the Trust in accordance with
its terms.

         20.      The Guarantee Agreement has been duly authorized, executed,
and delivered by the Company and, assuming the due authorization, execution and
delivery by the Trustee, constitutes a valid and binding instrument of the
Company, enforceable against the Company in accordance with its terms.

         21.      Each of the Operative Documents to which the Company is a
party (other than the Placement Agreement and the Capital Securities
Subscription Agreement, the Amended Declaration and the Guarantee Agreement, as
to which we have opined in paragraphs 13, 14 and 20 above) has been duly
authorized, executed and delivered by the Company and constitutes a valid and
binding agreement of the Company, enforceable against the Company in accordance
with its terms.

         22.      The Subordinated Debt Securities have been duly authorized for
issuance by the Company pursuant to the Indenture and, when executed,
authenticated and delivered in the manner provided for in the Indenture and paid
for in accordance with the Debenture Subscription Agreement, will constitute
valid and binding obligations of the Company and will entitle the holders
thereof to the benefits of the Indenture, enforceable against the Company in
accordance with their terms.

         23.      The execution, delivery and performance of the Operative
Documents, as applicable, by the Company and the Trust and the consummation by
the Company and the Trust of the transactions contemplated by the Operative
Documents, as applicable, will not result in any violation of the charter or
bylaws of the Company or the Bank[s] or the Amended Declaration or the
Certificate of Trust.

         24.      Assuming (i) the accuracy of the representations and
warranties, and compliance with the agreements, contained in the Placement
Agreement and the Capital Securities Subscription Agreement and (ii) that the
Capital Securities are sold in the manner contemplated by, and in accordance
with, the Placement Agreement, the Capital Securities Subscription Agreement and
the Amended Declaration, it is not necessary in connection with the offer, sale
and delivery of the Capital Securities by the Trust to the Purchaser to register
the


                                    Annex A-3
<PAGE>   23

Capital Securities, the Guarantee Agreement or the Subordinated Debt Securities
under the 1933 Act or to qualify an indenture under the Trust Indenture Act of
1939, as amended.

         25.      Neither the Company nor the Trust is, and, following the
issuance of the Capital Securities and the consummation of the transactions
contemplated by the Operative Documents and the application of the proceeds
therefrom, neither the Company nor the Trust will be, an "investment company"
required to be registered under the Investment Company Act of 1940, as amended.

         In rendering such opinions, such counsel may (A) state that its opinion
is limited to the laws of New York, the corporate laws of the State of Delaware
and the Federal laws of the United States and (B) rely as to matters involving
the application of laws of any jurisdiction other than New York and Delaware or
the United States, to the extent deemed proper and specified in such opinion,
upon the opinion of other counsel of good standing believed to be reliable and
who are satisfactory to you and as to matters of fact, to the extent deemed
proper, on certificates of responsible officers of the Company and public
officials.


                                    Annex A-4

<PAGE>   24

                                                                         ANNEX B


         Pursuant to Section 5(b) of the Placement Agreement, Richards, Layton &
Finger, P.A. shall deliver an opinion in the following form.

         (i)      The Trust is a duly formed and validly existing statutory
business trust in good standing under the Business Trust Act of the State of
Delaware with the business trust power and authority to enter into and perform
its obligations under this Agreement, the Securities and the Declaration and to
own property and conduct its business as described in the Declaration.

         (ii)     Under the Delaware Business Trust Act and the Declaration, the
execution and delivery by the Trust of this Agreement, and the performance by
the Trust of its obligations hereunder, have been duly authorized by all
necessary business trust action on the part of the Trust.

         (iii)    The Declaration constitutes a valid and binding obligation of
the Company and the Trustees, enforceable against the Company and the Trustees,
in accordance with its terms, subject, as to enforcement, to the effect upon the
Declaration of (a) bankruptcy, insolvency, moratorium, receivership,
liquidation, fraudulent conveyance and transfer, reorganization and other
similar laws relating to or affecting the remedies and rights of creditors, (b)
general principles of equity (regardless of whether considered or applied in a
proceeding in equity or at law), (c) considerations of public policy or the
effect of applicable law relating to fiduciary duties, and (d) principles of
course of dealing or course of performance and standards of good faith, fair
dealing, materiality or reasonableness that may be applied by a court to the
exercise of rights or remedies.

         (iv)     The Common Securities have been duly authorized for issuance
by the Trust and upon issuance and delivery by the Trust to the Company against
payment therefor as described in the Declaration, will be duly and validly
issued and will represent duly issued beneficial interests in the Trust. The
issuance of the Common Securities is not subject to preemptive or other similar
rights under the Declaration or the Business Trust Act; provided, that such
counsel may note that the holders of Common Securities may be required to make
payment or provide indemnity or security as set forth in the Declaration.

         (v)      The Capital Securities have been duly authorized for issuance
by the Trust, and, when issued and delivered against payment therefor as
provided herein, will be duly and validly issued and, subject to the
qualifications set forth herein, fully paid and non-assessable beneficial
interests in the Trust; the issuance of the Capital Securities is not subject to
preemptive or other similar rights under the Declaration or the Business Trust
Act; and the holders of the Capital Securities will be entitled to the same
limitation of personal liability extended to stockholders of private
corporations for profit organized under the General Corporation Law of the State
of Delaware; provided that such counsel need express no opinion as to any holder
of a Capital Security that is, was or becomes a named Trustee of the Trust. Such
counsel may note that the holders of the Capital Securities may be required to
make payment or provide indemnity or security as set forth in the Declaration.


                                    Annex B-1
<PAGE>   25

         (vi)     The issuance and sale by the Trust of the Securities, the
execution, delivery and performance by the Trust of the Agreement, the
consummation by the Trust of the transactions contemplated therein and the
compliance by the Trust with its obligations thereunder do not violate (a) any
of the provisions of the Certificate of Trust of the Trust or the Declaration or
(b) any Delaware law or Delaware administrative regulation applicable to the
Trust.

         (vii)    Assuming that the Trust derives no income from or connected
with sources within the State of Delaware and has no assets, activities (other
than having a Delaware trustee as required by the Delaware Business Trust Act
and the filing of documents with the Secretary of State of the State of
Delaware) or employees in the State of Delaware, no authorization, approval,
consent or order of any Delaware court or Delaware governmental authority or
Delaware agency is required to be obtained by the Trust solely as a result of
the issuance and sale of the Capital Securities, the consummation by the Trust
of the transactions contemplated herein or the compliance by the Trust with its
obligations hereunder.

         (viii)   Assuming that the Trust derives no income from or connected
with sources within the State of Delaware and has no assets, activities (other
than having a Delaware trustee as required by the Delaware Business Trust Act
and the filing of documents with the Secretary of State of the State of
Delaware) or employees in the State of Delaware, and assuming that the Trust is
treated as a grantor trust for federal income tax purposes and that the holders
of the Capital Securities are viewed for federal income tax purposes as owners
of either all of, or their liquidation and accrued but unpaid share of, the
Subordinated Debt Securities held by the Trust, the holders of Capital
Securities (other than those holders of Capital Securities, or persons who are
partners or S corporation shareholders for federal income tax purposes in such
holders of Capital Securities, who reside or are domiciled in the State of
Delaware or who are otherwise subject to income taxation in the State of
Delaware) will have no liability for income taxes imposed by the State of
Delaware solely as a result of their participation in the Trust, and the Trust
will not be liable for any income tax imposed by the State of Delaware (in
rendering the opinion expressed in this paragraph (viii), such counsel need
express no opinion concerning the securities laws of the State of Delaware).


                                    Annex B-2
<PAGE>   26

                                                                         ANNEX C


Pursuant to Section 5(c) of the Placement Agreement, counsel to the Company
shall deliver an opinion in substantially the following form:

Sandler O'Neill & Partners, L.P.
Two World Trade Center
104th Floor
New York, NY 10048


Ladies and Gentlemen:

         We have acted as special tax counsel to [Company], a [___________]
corporation (the "Company"), in connection with the offering by [Trust] (the
"Trust") of $[____] [[____]% Fixed Rate][Floating Rate] MMCapS[SM] (liquidation
amount $1,000 per capital security) (the "Capital Securities"). The Capital
Securities represent undivided beneficial ownership interests in
$[_____________] in aggregate principal amount of [[___]% Fixed Rate)[Floating
Rate] Junior Subordinated Debt Securities of the Company (the "Subordinated Debt
Securities"). This opinion letter is furnished pursuant to Section 5(c) of the
Placement Agreement dated [______], 2001, between the Company, the Trust and
you.

         In arriving at the opinions expressed below we have examined executed
copies of (i) the Amended and Restated Trust Agreement of the Trust dated the
date hereof (the "Declaration") and (ii) the Indenture relating to the issuance
of the Subordinated Debt Securities dated the date hereof (the "Indenture")
(together, the "Operative Documents"). In addition, we have made such
investigations of law and fact as we have deemed appropriate as a basis for the
opinion expressed below.

         It is our opinion that, under current law and assuming the performance
of the Operative Documents in accordance with the terms described therein, the
Subordinated Debt Securities will be treated for United States federal income
tax purposes as indebtedness of the Company.

         It is our opinion that the Trust will be classified for United States
federal income tax purposes as a grantor trust and not as an association taxable
as a corporation.

         Our opinion is based on the U.S. Internal Revenue Code of 1986, as
amended, Treasury regulations promulgated thereunder, and administrative and
judicial interpretations thereof, all as of the date hereof and all of which are
subject to change, possibly on a retroactive basis. In rendering this opinion,
we are expressing our views only as to the federal income tax laws of the United
States of America.


                                   Annex C-1
<PAGE>   27

                                                                         ANNEX D


         Pursuant to Section 5(d) of the Placement Agreement, counsel to The
Bank of New York (the "Trustee") shall deliver an opinion to the effect that:

                  (i)      The Trustee is a national banking association with
         trust powers duly organized and validly existing in good standing under
         the laws of the United States of America with all necessary corporate
         power and authority to execute, deliver and carry out and perform its
         obligations under the terms of the Guarantee Agreement, the Declaration
         and the Indenture;

                  (ii)     the execution, delivery and performance by the
         Trustee of the Guarantee Agreement, the Declaration and the Indenture
         have been duly authorized by all necessary corporate action on the part
         of the Trustee and each of the Guarantee Agreement, the Declaration and
         the Indenture has been duly executed and delivered by the Trustee, and
         constitutes the legal, valid and binding obligation of the Trustee,
         enforceable against it in accordance with its terms (subject to
         Bankruptcy and Equity);

                  (iii)    the execution, delivery and performance of the
         Guarantee Agreement, the Declaration and the Indenture by the Trustee
         do not conflict with or constitute a breach of the charter or by-laws
         of the Trustee; and

                  (iv)     no consent, approval or authorization of, or
         registration with or notice to, any governmental authority or agency of
         the United States of America governing the banking or trust powers of
         the Trustee is required for the execution, delivery or performance by
         it of the Guarantee Agreement, the Declaration and the Indenture.


                                    Annex D-1
<PAGE>   28

                                                                         ANNEX E


                  Pursuant to Section 5(e) of the Placement Agreement, Richards,
Layton & Finger, P.A. shall deliver an opinion to the following form.

         1.       The Delaware Trustee has been duly incorporated and is validly
existing in good standing as a banking corporation under the laws of the State
of Delaware.

         2.       The Delaware Trustee has the requisite corporate power and
authority to execute and deliver each Declaration of Trust, and has taken all
necessary corporate action to authorize the execution and delivery of each
Declaration of Trust.

         3.       Neither the execution, delivery and performance by the
Delaware Trustee of each Declaration of Trust, nor the consummation of any of
the transactions by the Delaware Trustee contemplated thereby, are in violation
of the charter or by-laws of the Delaware Trustee or of any law, governmental
rule or regulation of the State of Delaware or the United States governing the
banking or trust powers of the Delaware Trustee or, to our knowledge, without
independent investigation, of any indenture, mortgage, bank credit agreement,
note or bond purchase agreement, long-term lease, license or other agreement or
instrument to which the Delaware Trustee is a party or by which it is bound or,
to our knowledge, without independent investigation, of any judgment or order
applicable to the Delaware Trustee.

         4.       Neither the execution, delivery and performance by the
Delaware Trustee of each Declaration of Trust, nor the consummation of any of
the transactions by the Delaware Trustee contemplated thereby, requires the
consent or approval of, the withholding of objection on the part of, the giving
of notice to, the filing, registration or qualification with, or the taking of
any other action in respect of, any governmental authority or agency of the
State of Delaware or the United States of America governing the banking or trust
powers of the Delaware Trustee, except for the filing of the certificate of
trust for each Trust with the Office of the Secretary of State of the State of
Delaware pursuant to the Delaware Business Trust Act, 12 Del C. ss. 3801, et
seq.


                                    Annex E-1
<PAGE>   29

                               SCHEDULE 1(A)(VII)
 TO THE PLACEMENT AGREEMENT BETWEEN THE BANC CORPORATION, TBC CAPITAL STATUTORY
                 TRUST III AND SANDLER O'NEILL & PARTNERS, L.P.

         The Bank is currently a defendant in various legal proceedings pending
in state court arising out of certain losses that occurred in its Decatur branch
in late 1999, as discussed in "Item 3. Legal Proceedings" in the Company's
Annual Report on Form 10-K for the fiscal year ended December 31, 2000 and in
"Item 1. Legal Proceedings" in the Company's Quarterly Report on Form 10-Q for
the quarter ended March 31, 2001, copies of which are attached hereto.

         On Friday, July 6, 2001, The Bank and the plaintiffs in the Steenson
case successfully mediated their dispute. The parties expect to file a consent
order dismissing the lawsuit within approximately 14 days. The Bank believes
that the settlement will not have a material adverse impact on The Bank.

         The Bank has placed its Errors and Omissions/Directors and Officers,
and Fidelity Bond and general liability insurance carriers on notice regarding
the losses and the litigation discussed in the Company's '34 Act filings listed
above. The Fidelity Bond insurance carrier has tentatively denied The Bank's
proof of loss pending further investigation, which is on-going. The Bank does
not believe that there will be a material adverse effect on its financial
condition or results of operations, but there can be no assurance or guarantee
to that effect. With respect to the Errors and Omissions/Directors and Officers
insurance, the carrier has agreed that certain claims brought by the plaintiffs
in the listed litigation are covered claims, and the carrier has reserved its
rights with respect to certain other claims. Discussions between The Bank and
its insurance carriers are continuing. The Bank does not believe that the
outcome of the pending litigation will have a material adverse affect on its
financial condition or results of operations, but there can be no assurance or
guarantee to that effect.