<PAGE>   1
                                                                    EXHIBIT 4.6

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



                             SUBORDINATED INDENTURE



                           ENTERBANK HOLDINGS, INC.,
                                   AS ISSUER



                                       TO

                           WILMINGTON TRUST COMPANY,
                                   AS TRUSTEE






                      ___% JUNIOR SUBORDINATED DEBENTURES




                        DATED AS OF ______________, 1999



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


<PAGE>   2
                               TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                           Page

<S>                                                                        <C>
ARTICLE I - DEFINITIONS.......................................................1
         1.01     DEFINITIONS.................................................1

ARTICLE II - DESCRIPTION, TERMS, CONDITIONS, REGISTRATION
         AND EXCHANGE OF THE JUNIOR SUBORDINATED DEBENTURES...................9
         2.01     DESIGNATION AND PRINCIPAL AMOUNT............................9
         2.02     MATURITY....................................................9
         2.03     FORM AND PAYMENT...........................................10
         2.04     GLOBAL SUBORDINATED DEBENTURE..............................10
         2.05     INTEREST...................................................12
         2.06     EXECUTION, AUTHENTICATION, DELIVERY AND DATING.............13
         2.07     REGISTRATION AND TRANSFER..................................13
         2.08     MUTILATED, DESTROYED, LOST AND STOLEN JUNIOR SUBORDINATED
                  DEBENTURES.................................................14

ARTICLE III - REDEMPTION OF JUNIOR SUBORDINATED DEBENTURES...................15
         3.01     REDEMPTION.................................................15
         3.02     SPECIAL EVENT REDEMPTION...................................15
         3.03     OPTIONAL REDEMPTION BY COMPANY.............................16
         3.04     NOTICE OF REDEMPTION.......................................16
         3.05     PAYMENT UPON REDEMPTION....................................17
         3.06     NO SINKING FUND............................................18

ARTICLE IV - EXTENSION OF INTEREST PAYMENT PERIOD............................18
         4.01     EXTENSION OF INTEREST PAYMENT PERIOD.......................18
         4.02     NOTICE OF EXTENSION........................................19
         4.03     LIMITATION OF TRANSACTIONS DURING EXTENSION................19

ARTICLE V - PARTICULAR COVENANTS OF THE COMPANY..............................19
         5.01     PAYMENT OF PRINCIPAL AND INTEREST..........................19
         5.02     MAINTENANCE OF AGENCY......................................20
         5.03     PAYING AGENTS..............................................20
         5.04     APPOINTMENT TO FILL VACANCY IN OFFICE OF TRUSTEE...........21
         5.05     COMPLIANCE WITH CONSOLIDATION PROVISIONS...................21
         5.06     RESTRICTIONS ON CERTAIN PAYMENTS...........................21
         5.07     COVENANTS AS TO THE TRUST..................................22

ARTICLE VI - SECURITYHOLDERS' LISTS AND REPORTS BY THE COMPANY AND THE
         TRUSTEE.............................................................22
</TABLE>


                                       ii
<PAGE>   3

<TABLE>
<S>                                                                         <C>
         6.01     COMPANY TO FURNISH TRUSTEE NAMES AND ADDRESSES OF
                  SECURITYHOLDERS............................................22
         6.02     PRESERVATION OF INFORMATION; COMMUNICATIONS WITH
                  SECURITYHOLDERS............................................23
         6.03     REPORTS BY THE COMPANY.....................................23
         6.04     REPORTS BY THE TRUSTEE.....................................24

ARTICLE VII - REMEDIES OF THE TRUSTEE AND SECURITYHOLDERS ON EVENT OF
                  DEFAULT....................................................24
         7.01     EVENTS OF DEFAULT..........................................24
         7.02     COLLECTION OF INDEBTEDNESS AND SUITS FOR ENFORCEMENT BY
                  TRUSTEE....................................................26
         7.03     APPLICATION OF MONEYS COLLECTED............................27
         7.04     LIMITATION ON SUITS........................................28
         7.05     RIGHTS AND REMEDIES CUMULATIVE; DELAY OR OMISSION NOT
                  WAIVER.....................................................29
         7.06     CONTROL BY SECURITYHOLDERS.................................29
         7.07     UNDERTAKING TO PAY COSTS...................................30

ARTICLE VIII - FORM OF JUNIOR SUBORDINATED DEBENTURE AND ORIGINAL ISSUE......30
         8.01     FORM OF JUNIOR SUBORDINATED DEBENTURE......................30
         8.02     ORIGINAL ISSUE OF JUNIOR SUBORDINATED DEBENTURES...........30

ARTICLE IX - CONCERNING THE TRUSTEE..........................................31
         9.01     CERTAIN DUTIES AND RESPONSIBILITIES OF THE TRUSTEE.........31
         9.02     CERTAIN RIGHTS OF TRUSTEE..................................32
         9.03     TRUSTEE NOT RESPONSIBLE FOR RECITALS OR ISSUANCE OF THE
                  JUNIOR SUBORDINATED DEBENTURES.............................33
         9.04     MAY HOLD JUNIOR SUBORDINATED DEBENTURES....................34
         9.05     MONEYS HELD IN TRUST.......................................34
         9.06     COMPENSATION AND REIMBURSEMENT.............................34
         9.07     RELIANCE ON OFFICERS' CERTIFICATE..........................35
         9.08     DISQUALIFICATION; CONFLICTING INTERESTS....................35
         9.09     CORPORATE TRUSTEE REQUIRED; ELIGIBILITY....................35
         9.10     RESIGNATION AND REMOVAL; APPOINTMENT OF SUCCESSOR..........35
         9.11     ACCEPTANCE OF APPOINTMENT BY SUCCESSOR.....................37
         9.12     MERGER, CONVERSION, CONSOLIDATION OR SUCCESSION TO
                  BUSINESS...................................................37
         9.13     PREFERENTIAL COLLECTION OF CLAIMS AGAINST THE COMPANY......37
         9.14     APPOINTMENT OF AUTHENTICATING AGENT........................38
</TABLE>


                                      iii
<PAGE>   4

<TABLE>
<S>                                                                         <C>
ARTICLE X - CONCERNING THE SECURITYHOLDERS...................................39
         10.01    EVIDENCE OF ACTION BY SECURITYHOLDERS......................39
         10.02    PROOF OF EXECUTION BY SECURITYHOLDERS......................40
         10.03    WHO MAY BE DEEMED OWNERS...................................40
         10.04    CERTAIN JUNIOR SUBORDINATED DEBENTURES OWNED BY COMPANY
                  DISREGARDED................................................40
         10.05    ACTIONS BINDING ON FUTURE SECURITYHOLDERS..................41

ARTICLE XI - SUPPLEMENTAL INDENTURES.........................................41
         11.01    SUPPLEMENTAL INDENTURES WITHOUT THE CONSENT OF
                  SECURITYHOLDERS............................................41
         11.02    SUPPLEMENTAL INDENTURES WITH CONSENT OF SECURITYHOLDERS....42
         11.03    EFFECT OF SUPPLEMENTAL INDENTURES..........................43
         11.04    JUNIOR SUBORDINATED DEBENTURES AFFECTED BY SUPPLEMENTAL
                  INDENTURES.................................................43
         11.05    EXECUTION OF SUPPLEMENTAL INDENTURES.......................43

ARTICLE XII - SUCCESSOR CORPORATION..........................................44
         12.01    COMPANY MAY CONSOLIDATE, ETC...............................44
         12.02    SUCCESSOR SUBSTITUTED......................................44
         12.03    EVIDENCE OF CONSOLIDATION, ETC., TO TRUSTEE................44

ARTICLE XIII - SATISFACTION AND DISCHARGE....................................45
         13.01    SATISFACTION AND DISCHARGE OF INDENTURE....................45
         13.02    DISCHARGE OF OBLIGATIONS...................................45
         13.03    DEPOSITED MONEYS TO BE HELD IN TRUST.......................45
         13.04    PAYMENT OF MONEYS HELD BY PAYING AGENTS....................46
         13.05    REPAYMENT TO COMPANY.......................................46

ARTICLE XIV - IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS AND
                DIRECTORS....................................................46
         14.01    NO RECOURSE................................................46

ARTICLE XV - MISCELLANEOUS PROVISIONS........................................47
         15.01    EFFECT ON SUCCESSORS AND ASSIGNS...........................47
         15.02    ACTIONS BY SUCCESSOR.......................................47
         15.03    SURRENDER OF COMPANY POWERS................................47
         15.04    NOTICES....................................................47
         15.05    GOVERNING LAW..............................................47
         15.06    TREATMENT OF JUNIOR SUBORDINATED DEBENTURES AS DEBT........47
         15.07    COMPLIANCE CERTIFICATES AND OPINIONS.......................48
</TABLE>


                                       iv
<PAGE>   5

<TABLE>
<S>                                                                         <C>
         15.08    PAYMENTS ON BUSINESS DAYS..................................48
         15.09    CONFLICT WITH TRUST INDENTURE ACT..........................48
         15.10    COUNTERPARTS...............................................48
         15.11    SEPARABILITY...............................................48
         15.12    ASSIGNMENT.................................................49
         15.13    ACKNOWLEDGMENT OF RIGHTS...................................49

ARTICLE XVI - SUBORDINATION OF JUNIOR SUBORDINATED DEBENTURES................49
         16.01    AGREEMENT TO SUBORDINATE...................................49
         16.02    DEFAULT ON SENIOR AND SUBORDINATED DEBT....................49
         16.03    LIQUIDATION; DISSOLUTION; BANKRUPTCY.......................50
         16.04    SUBROGATION................................................51
         16.05    TRUSTEE TO EFFECTUATE SUBORDINATION........................52
         16.06    NOTICE BY THE COMPANY......................................52
         16.07    RIGHTS OF THE TRUSTEE; HOLDERS OF SENIOR AND SUBORDINATED
                  DEBT.......................................................53
         16.08    SUBORDINATION MAY NOT BE IMPAIRED..........................53

EXHIBIT A...................................................................A-1
</TABLE>


                                       v
<PAGE>   6

                            ENTERBANK HOLDINGS, INC.
          RECONCILIATION AND TIE BETWEEN TRUST INDENTURE ACT OF 1939,
                    AS AMENDED, AND SUBORDINATED INDENTURE,
                        DATED AS OF ______________, 1999


<TABLE>
<CAPTION>
TRUST INDENTURE ACT SECTION                 SUBORDINATED INDENTURE SECTION

<S>                                         <C>
Section 310                                                     15.09
Section 310(b)                                                   9.08
Section 311                                                     15.09
Section 311(a)                                                   9.13
           (b)                                                   9.13
Section 312                                                     15.09
Section 312(b)                                                   6.02
Section 313                                                     15.09
Section 313(a)                                                   6.04
           (b)                                                   6.04
           (c)                                                   6.04
Section 314                                                     15.09
Section 315                                                     15.09
Section 316                                                     15.09
Section 317                                                     15.09
</TABLE>

NOTE: This reconciliation and tie shall not, for any purpose, be deemed to be a
part of the Subordinated Indenture.


                                       vi
<PAGE>   7

                             SUBORDINATED INDENTURE

         SUBORDINATED INDENTURE (the "Indenture"), dated as of ____________,
1999, between ENTERBANK HOLDINGS, INC., a Delaware corporation (the "Company")
and WILMINGTON TRUST COMPANY, a Delaware banking corporation, as trustee (the
"Trustee");

         WHEREAS, for its lawful corporate purposes, the Company has duly
authorized the execution and delivery of this Indenture to provide for the
issuance of its securities to be known as its __% Junior Subordinated
Debentures due _____________, 2029 (hereinafter referred to as the "Junior
Subordinated Debentures"), the form and substance of such Junior Subordinated
Debentures and the terms, provisions and conditions thereof to be set forth as
provided in this Indenture; and

         WHEREAS, EBH Capital Trust I, a Delaware statutory business trust (the
"Trust"), has offered to the public $_____[A]_____ aggregate liquidation amount
of its ___% Cumulative Trust Preferred Securities (the "Preferred Securities"),
representing undivided beneficial interests in the assets of the Trust and
proposes to invest the proceeds from such offering, together with the proceeds
of the issuance and sale by the Trust to the Company of $____[B]____ aggregate
liquidation amount of its __% Common Securities, in $_[A]+[B]__ aggregate
principal amount of the Junior Subordinated Debentures; and

         WHEREAS, the Company has requested that the Trustee execute and
deliver this Indenture and all requirements necessary to make this Indenture a
valid instrument in accordance with its terms, and to make the Junior
Subordinated Debentures, when executed by the Company and authenticated and
delivered by the Trustee, the valid obligations of the Company; and

         WHEREAS, to provide the terms and conditions upon which the Junior
Subordinated Debentures are to be authenticated, issued and delivered, the
Company has duly authorized the execution and delivery of this Indenture; and

         WHEREAS, all things necessary to make this Indenture a valid agreement
of the Company, in accordance with its terms, have been done.

         NOW, THEREFORE, in consideration of the premises and the purchase of
the Junior Subordinated Debentures by the holders thereof, it is mutually
covenanted and agreed as follows for the equal and ratable benefit of the
holders of Junior Subordinated Debentures:

                                   ARTICLE I
                                  DEFINITIONS

         1.01 DEFINITIONS. The terms defined in this Section (except as in this
Indenture otherwise expressly provided or unless the context otherwise
requires) for all purposes of this Indenture and of any indenture supplemental
hereto shall have the respective meanings specified in this Section and shall
include the plural as well as the singular. All other terms used in this
Indenture that are defined in the Trust Indenture Act of 1939, as amended, or
that are by reference in said Trust Indenture Act defined in the Securities Act
of 1933, as amended (except as herein otherwise

<PAGE>   8

expressly provided or unless the context otherwise requires), shall have the
meanings assigned to such terms in said Trust Indenture Act and in said
Securities Act as in force at the date of the execution of this Indenture.

         "Accelerated Maturity Date" means, if the Company elects to accelerate
the Maturity Date in accordance with Section 2.02, the date selected by the
Company which is prior to the Scheduled Maturity Date, but is after
____________, 2004.

         "Additional Sums" shall have the meaning set forth in Section 2.05(c).

         "Administrative Trustees" has the meaning set forth in the Trust
Agreement.

         "Affiliate" means, with respect to a specified Person, (a) any Person
directly or indirectly owning, controlling or holding with power to vote 10% or
more of the outstanding voting securities or other ownership interests of the
specified Person, (b) any Person 10% or more of whose outstanding voting
securities or other ownership interests are directly or indirectly owned,
controlled or held with power to vote by the specified Person, (c) any Person
directly or indirectly controlling, controlled by, or under common control with
the specified Person, (d) a partnership in which the specified Person is a
general partner, (e) any officer or director of the specified Person, and (f)
if the specified Person is an individual, any entity of which the specified
Person is an officer, director or general partner.

         "Authenticating Agent" means an authenticating agent with respect to
the Junior Subordinated Debentures appointed by the Trustee pursuant to Section
9.14.

         "Bankruptcy Law" means Title 11, U.S. Code, or any similar federal or
state law for the relief of debtors.

         "Board of Directors" means the Board of Directors of the Company or
any duly authorized committee of such Board.

         "Board Resolution" means a copy of a resolution certified by the
Secretary or an Assistant Secretary of the Company to have been duly adopted by
the Board of Directors and to be in full force and effect on the date of such
certification.

         "Business Day" means any day other than a day on which federal or
state banking institutions in the State of Missouri or Delaware are authorized
or obligated by law, executive order or regulation to close or a day on which
the Trustee is closed.

         "Capital Treatment Event" means the reasonable determination by the
Company that, as a result of any amendment to, or change (including any
proposed change) in, the laws (or any regulations thereunder) of the United
States or any political subdivision thereof or therein, or as a result of any
official or administrative pronouncement or action or judicial decision
interpreting or


                                       2
<PAGE>   9

applying such laws or regulations, which amendment or change is effective or
such proposed change, pronouncement or decision is announced on or after the
date of issuance of the Preferred Securities under the Trust Agreement, there
is more than an insubstantial risk of impairment of the Company's ability to
treat the Preferred Securities (or any substantial portion thereof) as Tier I
Capital for purposes of any then applicable capital adequacy guidelines of the
Federal Reserve, as then in effect and applicable to the Company.

         "Certificate" means a certificate signed by the principal executive
officer, the principal financial officer or the principal accounting officer of
the Company. The Certificate need not comply with the provisions of Section
15.07.

         "Commission" means the Securities and Exchange Commission, as from
time to time constituted, created under the Exchange Act, or, if at any time
after the execution of this Indenture such Commission is not existing and
performing the duties now assigned to it under the Trust Indenture Act, then
the body performing such duties at such time.

         "Common Securities" means undivided beneficial interests in the assets
of the Trust which rank pari passu with Preferred Securities issued by the
Trust; provided, however, that upon the occurrence of an Event of Default, the
rights of holders of Common Securities to payment in respect of Distributions
and payments upon liquidation, redemption and otherwise are subordinated to the
rights of holders of Preferred Securities.

         "Company" means Enterbank Holdings, Inc., a corporation duly organized
and existing under the laws of the State of Delaware, and, subject to the
provisions of Article XII, shall also include its successors and assigns.

         "Compounded Interest" shall have the meaning set forth in Section
4.01.

         "Corporate Trust Office" means the office of the Trustee at which, at
any particular time, its corporate trust business shall be principally
administered, which office at the date hereof is located at 1100 North Market
Street, Wilmington, Delaware 19890-0001, Attention: Corporate Trust
Administration.

         "Coupon Rate" shall have the meaning set forth in Section 2.05(a).

         "Custodian" means any receiver, trustee, assignee, liquidator, or
similar official under any Bankruptcy Law.

         "Debt" means with respect to any Person, whether recourse is to all or
a portion of the assets of such Person and whether or not contingent, (a) every
obligation of such Person for money borrowed; (b) every obligation of such
Person evidenced by bonds, debentures, notes or other similar instruments,
including obligations incurred in connection with the acquisition of property,
assets or businesses; (c) every reimbursement obligation of such Person with
respect to letters of credit,


                                       3
<PAGE>   10

bankers' acceptances or similar facilities issued for the account of such
Person; (d) every obligation of such Person issued or assumed as the deferred
purchase price of property or services (but excluding trade accounts payable or
accrued liabilities arising in the ordinary course of business); (e) every
capital lease obligation of such Person; and (f) every obligation of the type
referred to in clauses (a) through (e) of another Person and all dividends of
another Person the payment of which, in either case, such Person has guaranteed
or for which such Person is responsible or liable, directly or indirectly, as
obligor or otherwise.

         "Default" means any event, act or condition that with notice or lapse
of time, or both, would constitute an Event of Default.

         "Deferred Interest" shall have the meaning set forth in Section 4.01.

         "Depositary" means, with respect to Junior Subordinated Debentures
issued as a Global Subordinated Debenture, The Depository Trust Company, New
York, New York, another clearing agency, or any successor registered as a
clearing agency under the Exchange Act, or other applicable statute or
regulation, which, in each case, shall be designated by the Company pursuant to
either Section 2.01 or 2.04.

         "Dissolution Event" means that as a result of the occurrence and
continuation of a Special Event, the Trust is to be dissolved in accordance
with the Trust Agreement and the Junior Subordinated Debentures held by the
Property Trustee are to be distributed to the holders of the Trust Securities
issued by the Trust pro rata in accordance with the Trust Agreement.

         "Distributions" shall have the meaning set forth in the Trust
Agreement.

         "Event of Default" means any event specified in Section 7.01,
continued for the period of time, if any, therein designated.

         "Exchange Act" means the Securities Exchange Act of 1934, as amended.

         "Extended Interest Payment Period" shall have the meaning set forth in
Section 4.01.

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

         "Global Subordinated Debenture" means a Junior Subordinated Debenture
executed by the Company and delivered by the Trustee to the Depositary or
pursuant to the Depositary's instruction, all in accordance with this
Indenture, which shall be registered in the name of the Depositary or its
nominee.

         "Governmental Obligations" means securities that are (a) direct
obligations of the United States of America for the payment of which its full
faith and credit is pledged or (b) obligations of a Person controlled or
supervised by and acting as an agency or instrumentality of the United States


                                       4
<PAGE>   11

of America, the payment of which is unconditionally guaranteed as a full faith
and credit obligation by the United States of America that, in either case, are
not callable or redeemable at the option of the issuer thereof, and shall also
include a depositary receipt issued by a bank (as defined in Section 3(a)(2) of
the Securities Act of 1933, as amended) as custodian with respect to any such
Governmental Obligation or a specific payment of principal of or interest on
any such Governmental Obligation held by such custodian for the account of the
holder of such depositary receipt; provided, however, that (except as required
by law) such custodian is not authorized to make any deduction from the amount
payable to the holder of such depositary receipt from any amount received by
the custodian in respect of the Governmental Obligation or the specific payment
of principal of or interest on the Governmental Obligation evidenced by such
depositary receipt.

         "Herein," "hereof" and "hereunder," and other words of similar import,
refer to this Indenture as a whole and not to any particular Article, Section
or other subdivision.

         "Indenture" means this instrument as originally executed or as it may
from time to time be supplemented or amended by one or more indentures
supplemental hereto entered into in accordance with the terms hereof.

         "Interest Payment Date," when used with respect to any installment of
interest on the Junior Subordinated Debentures, means the date specified in the
Junior Subordinated Debenture as the fixed date on which an installment of
interest with respect to the Junior Subordinated Debentures is due and payable.

         "Investment Company Act" means the Investment Company Act of 1940, as
amended.

         "Investment Company Event" means the receipt by the Company and the
Trust of an Opinion of Counsel experienced in such matters to the effect that,
as a result of the occurrence of a change in law or regulation or a change in
interpretation or application of law or regulation by any legislative body,
court, governmental agency or regulatory authority (a "Change in Investment
Company Act Law"), the Trust is or will be considered an "investment company"
that is required to be registered under the Investment Company Act, which
Change in Investment Company Act Law becomes effective on or after the date of
original issuance of the Preferred Securities under the Trust Agreement.

         "Junior Subordinated Debentures" means the __% Junior Subordinated
Debentures due 2029 authenticated and delivered under this Indenture.

         "Liquidation Amount" means the stated amount of $8.00 per Trust
Security.

         "Maturity Date" shall have the meaning set forth in Section 2.02.

         "Non Book-Entry Preferred Securities" shall have the meaning set forth
in Section 2.04(a).


                                       5
<PAGE>   12

         "Officers' Certificate" means a certificate signed by the Chief
Executive Officer, the President or a Vice President and by the Chief
Accounting Officer or the Controller or an Assistant Controller or the
Secretary or an Assistant Secretary of the Company that is delivered to the
Trustee in accordance with the terms hereof. Each such certificate shall
include the statements provided for in Section 15.07, if and to the extent
required by the provisions thereof.

         "Opinion of Counsel" means an opinion in writing of legal counsel, who
may be an employee of or counsel for the Company, that is delivered to the
Trustee in accordance with the terms hereof. Each such opinion shall include the
statements provided for in Section 15.07, if and to the extent required by the
provisions thereof.

         "Outstanding," when used with reference to Junior Subordinated
Debentures means, subject to the provisions of Section 10.04, as of any
particular time, all Junior Subordinated Debentures theretofore authenticated
and delivered by the Trustee under this Indenture, except (a) Junior
Subordinated Debentures theretofore canceled by the Trustee or any paying
agent, or delivered to the Trustee or any paying agent for cancellation or that
have previously been canceled; (b) Junior Subordinated Debentures or portions
thereof for the payment or redemption of which moneys or Governmental
Obligations in the necessary amount shall have been deposited in trust with the
Trustee or with any paying agent (other than the Company) or shall have been
set aside and segregated in trust by the Company (if the Company shall act as
its own paying agent); provided, however, that if such Junior Subordinated
Debentures or portions of such Junior Subordinated Debentures are to be
redeemed prior to the maturity thereof, notice of such redemption shall have
been given as provided in Article III, or provision satisfactory to the Trustee
shall have been made for giving such notice; and (c) Junior Subordinated
Debentures in lieu of or in substitution for which other Junior Subordinated
Debentures shall have been authenticated and delivered pursuant to the terms of
Section 2.08.

         "Person" means any individual, corporation, partnership, joint
venture, joint-stock company, unincorporated organization or government or any
agency or political subdivision thereof.

         "Predecessor Junior Subordinated Debenture" means every previous
Junior Subordinated Debenture evidencing all or a portion of the same debt as
that evidenced by such particular Junior Subordinated Debenture; and, for the
purposes of this definition, any Junior Subordinated Debenture authenticated
and delivered under Section 2.08 in lieu of a lost, destroyed or stolen Junior
Subordinated Debenture shall be deemed to evidence the same debt as the lost,
destroyed or stolen Junior Subordinated Debenture.

         "Preferred Securities" means undivided beneficial interests in the
assets of the Trust which rank pari passu with Common Securities issued by the
Trust; provided, however, that upon the occurrence of an Event of Default, the
rights of holders of Common Securities to payment in respect of Distributions
and payments upon liquidation, redemption and otherwise are subordinated to the
rights of holders of Preferred Securities.


                                       6
<PAGE>   13

         "Preferred Securities Certificate" has the meaning set forth in the
Trust Agreement.

         "Preferred Securities Guarantee" means any guarantee that the Company
may enter into with the Property Trustee or other Persons that operates
directly or indirectly for the benefit of holders of Preferred Securities of
the Trust.

         "Property Trustee" has the meaning set forth in the Trust Agreement.

         "Redemption Price" means the amount equal to 100% of the principal
amount of Junior Subordinated Debentures to be redeemed plus any accrued and
unpaid interest thereon to the date of the redemption of such Junior
Subordinated Debentures.

         "Responsible Officer" when used with respect to the Trustee means any
Vice President or any corporate trust officer with direct responsibility for
the administration of this Indenture or any other officer or assistant officer
of the Trustee customarily performing functions similar to those performed by
the Persons who at the time shall be such officers, respectively, or to whom
any corporate trust matter is referred because of his or her knowledge of and
familiarity with the particular subject.

         "Scheduled Maturity Date" means ______________, 2029.

         "Securities Register" and "Securities Registrar" have the respective
meanings specified in Section 2.07.

         "Securityholder," "Holder," "Registered Holder," or other similar
term, means the Person or Persons in whose name or names particular Junior
Subordinated Debentures shall be registered in the Securities Register.

         "Senior and Subordinated Debt" means the principal of (and premium, if
any) and interest, if any (including interest accruing on or after the filing
of any petition in bankruptcy or for reorganization relating to the Company
whether or not such claim for post-petition interest is allowed in such
proceeding), on Debt of the Company, whether incurred on or prior to the date
of this Indenture or thereafter incurred, unless, in the instrument creating or
evidencing the same or pursuant to which the same is outstanding, it is
provided that such obligations are not superior in right of payment to the
Junior Subordinated Debentures or to other Debt which is pari passu with, or
subordinated to, the Junior Subordinated Debentures; provided, however, that
Senior and Subordinated Debt shall not be deemed to include (a) any Debt of the
Company which when incurred and without respect to any election under section
1111(b) of the United States Bankruptcy Code of 1978, as amended, was without
recourse to the Company, (b) any Debt of the Company to any of its
Subsidiaries, (c) any Debt to any employee of the Company, (d) any Debt which
by its terms is subordinated to any trade accounts payable or accrued
liabilities arising in the ordinary course of business but only to the extent
that payments made to the holders of such Debt by the Holders of the Junior
Subordinated Debentures as a result of the subordination provisions of this
Indenture would


                                       7
<PAGE>   14

be greater than they otherwise would have been as a result of any obligation of
such Holders to pay amounts over to the obligees on such trade accounts payable
or accrued liabilities arising in the ordinary course of business as a result
of subordination provisions to which such Debt is subject, (e) the Preferred
Securities Guarantee, and (f) any other debt securities issued pursuant to this
Indenture.

         "Special Event" means a Tax Event, an Investment Company Event or a
Capital Treatment Event.

         "Subsidiary" means, with respect to any Person, (a) any corporation at
least a majority of whose outstanding Voting Stock shall at the time be owned,
directly or indirectly, by such Person, or by one or more of its Subsidiaries,
or by such Person and one or more of its Subsidiaries, (b) any general
partnership, joint venture or similar entity, at least a majority of whose
outstanding partnership or similar interests shall at the time be owned by such
Person, or by one or more of its Subsidiaries, or by such Person and one or
more of its Subsidiaries, and (c) any limited partnership of which such Person
or any of its Subsidiaries is a general partner.

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

         "Trust" means EBH Capital Trust I, a Delaware statutory business trust
created for the purpose of issuing Trust Securities in connection with the
issuance of Junior Subordinated Debentures under this Indenture.

         "Trust Agreement" means the Amended and Restated Trust Agreement,
dated as of _______________, 1999, of the Trust.

         "Trustee" means Wilmington Trust Company and, subject to the
provisions of Article IX, shall also include its successors and assigns, and,
if at any time there is more than one Person acting in such capacity hereunder,
"Trustee" shall mean each such Person.


                                       8
<PAGE>   15

         "Trust Indenture Act" means the Trust Indenture Act of 1939 as in
force at the date of execution of this Indenture; provided, however, that in
the event the Trust Indenture Act of 1939 is amended after such date, "Trust
Indenture Act" means, to the extent required by any such amendment, the Trust
Indenture Act of 1939 as so amended.

         "Trust Securities" means Common Securities and Preferred Securities of
the Trust.

         "Voting Stock" as applied to stock of any Person, means shares,
interests, participations or other equivalents in the equity interest (however
designated) in such Person having ordinary voting power for the election of a
majority of the directors (or the equivalent) of such Person, other than
shares, interests, participations or other equivalents having such power only
by reason of the occurrence of a contingency.

                                   ARTICLE II
                  DESCRIPTION, TERMS, CONDITIONS, REGISTRATION
               AND EXCHANGE OF THE JUNIOR SUBORDINATED DEBENTURES

         2.01 DESIGNATION AND PRINCIPAL AMOUNT. There is hereby authorized a
series of Securities designated the "__% Junior Subordinated Debentures due
2029," limited in aggregate principal amount to $__________, which amount shall
be as set forth in any written order of the Company for the authentication and
delivery of Junior Subordinated Debentures pursuant to Section 8.02 of this
Indenture.

         2.02     MATURITY.

                  (a) The Maturity Date will be either:

                      (i)  the Scheduled Maturity Date; or

                      (ii) if the Company elects to accelerate the Maturity
                  Date to be a date prior to the Scheduled Maturity Date in
                  accordance with Section 2.02(b), the Accelerated Maturity
                  Date.

                  (b) The Company may, at any time before the day which is 90
         days before the Scheduled Maturity Date, elect to shorten the Maturity
         Date only once to the Accelerated Maturity Date, provided that the
         Company has received the prior approval of the Federal Reserve if then
         required under applicable capital guidelines or policies of the
         Federal Reserve, but in no case shall such Accelerated Maturity Date
         be a date before ____________, 2004.

                  (c) If the Company elects to accelerate the Maturity Date in
         accordance with Section 2.02(b), the Company shall give notice to the
         Registered Holders of the Junior Subordinated Debentures, the Property
         Trustee and the Trustee of the acceleration of the


                                       9
<PAGE>   16

         Maturity Date and the Accelerated Maturity Date at least 90 days
         before the Accelerated Maturity Date.

         2.03 FORM AND PAYMENT. Except as provided in Section 2.04, the Junior
Subordinated Debentures shall be issued in fully registered certificated form
without interest coupons. Principal and interest on the Junior Subordinated
Debentures issued in certificated form will be payable, the transfer of such
Junior Subordinated Debentures will be registrable and such Junior Subordinated
Debentures will be exchangeable for Junior Subordinated Debentures bearing
identical terms and provisions at the office or agency of the Trustee;
provided, however, that payment of interest may be made at the option of the
Company by check mailed to the Holder at such address as shall appear in the
Securities Register. Notwithstanding the foregoing, so long as the Holder of
any Junior Subordinated Debentures is the Property Trustee, the payment of the
principal of and interest (including Compounded Interest and Additional Sums,
if any) on such Junior Subordinated Debentures held by the Property Trustee
will be made at such place and to such account as may be designated by the
Property Trustee.

         2.04     GLOBAL SUBORDINATED DEBENTURE.

                  (a)      In connection with a Dissolution Event:

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

                           (ii) if any Preferred Securities are held in non
                  book-entry certificated form, the Junior Subordinated
                  Debentures in certificated form may be presented to the
                  Trustee by the Property Trustee and any Preferred Securities
                  Certificate which represents Preferred Securities other than
                  Preferred Securities held by the Depositary or its nominee
                  ("Non Book-Entry Preferred Securities") will be deemed to
                  represent beneficial interests in Junior Subordinated
                  Debentures presented to the Trustee by the Property Trustee
                  having an aggregate principal amount equal to the aggregate
                  Liquidation Amount of the Non Book-Entry Preferred Securities
                  until such Preferred Securities Certificates are presented to
                  the Securities Registrar for transfer or reissuance at which
                  time such Preferred Securities Certificates will be canceled
                  and


                                       10
<PAGE>   17

                  a Junior Subordinated Debenture, registered in the name of
                  the holder of the Preferred Securities Certificate or the
                  transferee of the holder of such Preferred Securities
                  Certificate, as the case may be, with an aggregate principal
                  amount equal to the aggregate Liquidation Amount of the
                  Preferred Securities Certificate canceled, will be executed
                  by the Company and delivered to the Trustee for
                  authentication and delivery in accordance with this
                  Indenture. On issue of such Junior Subordinated Debentures,
                  Junior Subordinated Debentures with an equivalent aggregate
                  principal amount that were presented by the Property Trustee
                  to the Trustee will be deemed to have been canceled.

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

                  (c) If at any time the Depositary notifies the Company that
         it is unwilling or unable to continue as Depositary or if at any time
         the Depositary for such series shall no longer be registered or in
         good standing under the Exchange Act or other applicable statute or
         regulation, and a successor Depositary for such series is not
         appointed by the Company within 90 days after the Company receives
         such notice or becomes aware of such condition, as the case may be,
         the Company will execute, and the Trustee, upon written notice from
         the Company, will authenticate and deliver the Junior Subordinated
         Debentures in definitive registered form without coupons, in
         authorized denominations, and in an aggregate principal amount equal
         to the principal amount of the Global Subordinated Debenture in
         exchange for such Global Subordinated Debenture. In addition, the
         Company may at any time determine that the Junior Subordinated
         Debentures shall no longer be represented by a Global Subordinated
         Debenture. In such event the Company will execute, and the Trustee,
         upon receipt of an Officers' Certificate evidencing such determination
         by the Company, will authenticate and deliver the Junior Subordinated
         Debentures in definitive registered form without coupons, in
         authorized denominations, and in an aggregate principal amount equal
         to the principal amount of the Global Subordinated Debenture in
         exchange for such Global Subordinated Debenture. Upon the exchange of
         the Global Subordinated Debenture for such Junior Subordinated
         Debentures in definitive registered form without coupons, in
         authorized denominations, the Global Subordinated Debenture shall be
         canceled by the Trustee. Such Junior Subordinated Debentures in
         definitive registered form issued in exchange for the Global
         Subordinated Debenture shall be registered in such names and in such
         authorized denominations as the Depositary, pursuant to instructions
         from its direct or indirect participants or otherwise, shall instruct
         the Trustee. The Trustee shall deliver such Junior Subordinated
         Debentures to the Depositary for delivery to the Persons in whose
         names such Junior Subordinated Debentures are so registered.


                                       11
<PAGE>   18

         2.05     INTEREST.

                  (a) Each Junior Subordinated Debenture will bear interest at
         the rate of __% per annum (the "Coupon Rate") from the original date
         of issuance until the principal thereof becomes due and payable, and
         on any overdue principal and (to the extent that payment of such
         interest is enforceable under applicable law) on any overdue
         installment of interest at the Coupon Rate, compounded quarterly,
         payable (subject to the provisions of Article IV) quarterly in arrears
         on the fifteenth day of March, June, September and December in each
         year (each, an "Interest Payment Date"), commencing on December 15,
         1999, to the Person in whose name such Junior Subordinated Debenture
         or any Predecessor Junior Subordinated Debenture is registered at the
         close of business on the regular record date for such interest
         installment, which, in respect of (i) Junior Subordinated Debentures
         of which the Property Trustee is the Holder and the Preferred
         Securities are in book-entry-only form or (ii) a Global Subordinated
         Debenture, shall be the close of business on the Business Day next
         preceding that Interest Payment Date. Notwithstanding the foregoing
         sentence, if (A) the Junior Subordinated Debentures are held by the
         Property Trustee and the Preferred Securities are no longer in
         book-entry only form or (B) the Junior Subordinated Debentures are not
         represented by a Global Subordinated Debenture, the record date for
         such interest installment shall be the first day of the month in which
         such payment is to be made. The amount of each interest payment due
         with respect to the Junior Subordinated Debentures will include
         amounts accrued through the date the interest payment is due.

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

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


                                       12
<PAGE>   19

         2.06     EXECUTION, AUTHENTICATION, DELIVERY AND DATING.  The Junior
Subordinated Debentures shall be executed on behalf of the Company by its Chief
Executive Officer, its President or any Vice President and attested by its
Secretary or Assistant Secretary. The signature of any of these officers on the
Junior Subordinated Debentures may be manual or facsimile.

         Junior Subordinated Debentures bearing the manual or facsimile
signatures of individuals who were at any time the proper officers of the
Company shall bind the Company, notwithstanding that such individuals or any of
them have ceased to hold such offices prior to the authentication and delivery
of such Junior Subordinated Debentures or did not hold such offices at the date
of such Junior Subordinated Debentures.

         At any time and from time to time after the execution and delivery of
this Indenture, the Company may deliver Junior Subordinated Debentures executed
by the Company to the Trustee for authentication, together with a Company order
for the authentication and delivery of such Junior Subordinated Debentures. The
Trustee in accordance with such Company order shall authenticate and deliver
such Junior Subordinated Debentures as provided in this Indenture and not
otherwise.

         Upon the initial issuance, each Junior Subordinated Debenture shall be
dated ______________, 1999, and thereafter Junior Subordinated Debentures
issued hereunder shall be dated the date of their authentication.

         No Junior Subordinated Debenture shall be entitled to any benefit
under this Indenture or be valid or obligatory for any purpose unless there
appears on such Junior Subordinated Debenture a certificate of authentication
substantially in the form provided for herein executed by the Trustee by manual
signature, and such certificate upon any Junior Subordinated Debenture shall be
conclusive evidence, and the only evidence, that such Junior Subordinated
Debenture has been duly authenticated and delivered hereunder and is entitled
to the benefits of this Indenture.

         2.07 REGISTRATION AND TRANSFER. The Company shall cause to be kept at
the Corporate Trust Office of the Trustee a register (the register maintained
in such office or any other office or agency pursuant to Section 5.02 being
herein sometimes referred to as the "Securities Register") in which, subject to
such reasonable regulations as it may prescribe, the Company shall provide for
the registration of the Junior Subordinated Debentures and transfers of the
Junior Subordinated Debentures. The Trustee is hereby appointed "Securities
Registrar" for the purpose of registering the Junior Subordinated Debentures
and transfers of the Junior Subordinated Debentures as herein provided.

         Upon surrender for registration of transfer of any Junior Subordinated
Debenture at an office or agency of the Company designated pursuant to Section
5.02 for such purpose, the Company shall execute, and the Trustee shall
authenticate and deliver, in the name of the designated transferee or
transferees, a new Junior Subordinated Debenture of the authorized
denomination.


                                       13
<PAGE>   20

         All Junior Subordinated Debentures issued upon any registration of
transfer of Junior Subordinated Debentures shall be valid obligations of the
Company, evidencing the same debt and entitled to the same benefits under this
Indenture as the Junior Subordinated Debentures surrendered upon such
registration of transfer.

         Every Junior Subordinated Debenture presented or surrendered for
registration of transfer shall be duly endorsed for transfer (if so required by
the Company or the Trustee), or shall be accompanied by a written instrument of
transfer in form satisfactory to the Company and the Securities Registrar duly
executed by the Holder thereof or such Holder's attorney duly authorized in
writing.

         No service charge shall be made for any registration of transfer of
Junior Subordinated Debentures, but the Company may require payment of a sum
sufficient to cover any tax or other governmental charge that may be imposed in
connection with any registration of transfer of Junior Subordinated Debentures.

         The Company shall not be required to issue or register the transfer of
any Junior Subordinated Debenture during a period beginning at the opening of
business 15 days before the day of the mailing of a notice of redemption of
Junior Subordinated Debentures selected for redemption pursuant to Article III
and ending at the close of business on the day of such mailing.

         2.08     MUTILATED, DESTROYED, LOST AND STOLEN JUNIOR
SUBORDINATED DEBENTURES.  If any mutilated Junior Subordinated Debenture is
surrendered to the Trustee, the Company shall execute and the Trustee shall
authenticate and deliver in exchange therefor a new Junior Subordinated
Debenture of like tenor and principal amount and bearing a number not
contemporaneously outstanding.

         If there shall be delivered to the Company and the Trustee (a)
evidence to their satisfaction of the destruction, loss or theft of any Junior
Subordinated Debenture and (b) such security or indemnity as may be required by
them to save each of them harmless, then, in the absence of notice to the
Company or the Trustee that such Junior Subordinated Debenture has been
acquired by a protected purchaser, the Company shall execute and upon its
request the Trustee shall authenticate and deliver, in lieu of any such
destroyed, lost or stolen Junior Subordinated Debenture, a new Junior
Subordinated Debenture of like tenor and principal amount and bearing a number
not contemporaneously outstanding.

         In case any such mutilated, destroyed, lost or stolen Junior
Subordinated Debenture has become or is about to become due and payable, the
Company in its discretion may, instead of issuing a new Junior Subordinated
Debenture, pay such Junior Subordinated Debenture.

         Upon the issuance of any new Junior Subordinated Debenture under this
Section, the Company may require the payment of a sum sufficient to cover any
tax or other governmental charge


                                       14
<PAGE>   21

that may be imposed in relation thereto and any other expenses (including the
fees and expenses of the Trustee) connected therewith.

         Every new Junior Subordinated Debenture issued pursuant to this
Section in lieu of any destroyed, lost or stolen Junior Subordinated Debenture
shall constitute an original additional contractual obligation of the Company,
whether or not the destroyed, lost or stolen Junior Subordinated Debenture
shall be at any time enforceable by anyone, and shall be entitled to all of the
benefits of this Indenture.

         The provisions of this Section are exclusive and shall preclude (to
the extent lawful) all other rights and remedies with respect to the
replacement or payment of mutilated, destroyed, lost or stolen Junior
Subordinated Debentures.

                                  ARTICLE III
                  REDEMPTION OF JUNIOR SUBORDINATED DEBENTURES

         3.01 REDEMPTION. Subject to the Company having received prior approval
of the Federal Reserve, if then required under the applicable capital
guidelines or policies of the Federal Reserve, the Company may redeem the
Junior Subordinated Debentures in accordance with this Article III.

         3.02 SPECIAL EVENT REDEMPTION. Subject to the Company having received
the prior approval of the Federal Reserve, if then required under the
applicable capital guidelines or policies of the Federal Reserve, if a Special
Event has occurred and is continuing, then, notwithstanding Section 3.03, the
Company shall have the right upon not less than 30 days' nor more than 60 days'
notice to the Holders of the Junior Subordinated Debentures to redeem the
Junior Subordinated Debentures, in whole but not in part, for cash within 90
days following the occurrence of such Special Event (the "90-Day Period") at
the Redemption Price, provided that if at the time there is available to the
Company the opportunity to eliminate, within the 90-Day Period, the Tax Event
by taking some ministerial action ("Ministerial Action"), such as filing a form
or making an election, or pursuing some other similar reasonable measure which
has no adverse effect on the Company, the Trust or the Holders of the Trust
Securities issued by the Trust, the Company shall pursue such Ministerial
Action in lieu of redemption, and, provided, further, that the Company shall
have no right to redeem the Junior Subordinated Debentures while the Trust is
pursuing any Ministerial Action to eliminate the Tax Event. The Redemption
Price shall be paid prior to 2:00 p.m., St. Louis, Missouri time, on the date
of such redemption or such earlier time as the Company determines, provided
that the Company shall deposit with the Trustee an amount sufficient to pay the
Redemption Price by 12:00 noon, St. Louis, Missouri time, on the date such
Redemption Price is to be paid.


                                       15
<PAGE>   22

         3.03     OPTIONAL REDEMPTION BY COMPANY.

                  (a) Except as otherwise may be specified in this Indenture,
         the Company shall have the right to redeem the Junior Subordinated
         Debentures, in whole or in part, from time to time, on or after
         _____________, 2004, at the Redemption Price. Any redemption pursuant
         to this Section 3.03 will be made upon not less than 30 days' nor more
         than 60 days' notice to the Holders of the Junior Subordinated
         Debentures, at the Redemption Price. If the Junior Subordinated
         Debentures are only partially redeemed pursuant to this Section 3.03,
         the Junior Subordinated Debentures will be redeemed pro rata or by lot
         or by any other method utilized by the Trustee; provided, that if at
         the time of redemption the Junior Subordinated Debentures are
         registered as a Global Subordinated Debenture, the Depositary shall
         determine, in accordance with its procedures, the principal amount of
         such Junior Subordinated Debentures held by each Holder of Junior
         Subordinated Debentures to be redeemed. The Redemption Price shall be
         paid prior to 2:00 p.m., St. Louis, Missouri time, on the date of such
         redemption or at such earlier time as the Company determines provided
         that the Company shall deposit with the Trustee an amount sufficient
         to pay the Redemption Price by 12:00 noon, St. Louis, Missouri time,
         on the date such Redemption Price is to be paid.

                  (b) If a partial redemption of the Junior Subordinated
         Debentures would result in the delisting of the Preferred Securities
         issued by the Trust from the NASDAQ National Market or any national
         securities exchange or other organization on which the Preferred
         Securities may then be listed, if any, the Company shall not be
         permitted to effect such partial redemption and may only redeem the
         Junior Subordinated Debentures in whole or in part to such extent as
         would not cause such delisting.

         3.04     NOTICE OF REDEMPTION.

                  (a) In case the Company shall desire to exercise such right
         to redeem all or, as the case may be, a portion of the Junior
         Subordinated Debentures in accordance with the right reserved so to
         do, the Company shall, or shall cause the Trustee to, give notice of
         such redemption to Holders of the Junior Subordinated Debentures to be
         redeemed by mailing, first class postage prepaid, a notice of such
         redemption not less than 30 days and not more than 60 days before the
         date fixed for redemption to such Holders at their last addresses as
         they shall appear upon the Securities Register. Any notice that is
         mailed in the manner herein provided shall be conclusively presumed to
         have been duly given, whether or not the Registered Holder receives
         the notice. In any case, failure duly to give such notice to the
         Holder of any Junior Subordinated Debenture designated for redemption
         in whole or in part, or any defect in the notice, shall not affect the
         validity of the proceedings for the redemption of any other Junior
         Subordinated Debentures. In the case of any redemption of Junior
         Subordinated Debentures prior to the expiration of any restriction on
         such redemption provided elsewhere in this Indenture, the Company
         shall furnish the Trustee with an Officers' Certificate evidencing
         compliance with any such restriction.


                                       16
<PAGE>   23

                  Each such notice of redemption shall specify the date fixed
         for redemption and the Redemption Price, and shall state that payment
         of the Redemption Price of such Junior Subordinated Debentures to be
         redeemed will be made at the office or agency of the Property Trustee
         in Wilmington, Delaware upon presentation and surrender of such Junior
         Subordinated Debentures, that interest accrued to the date fixed for
         redemption will be paid as specified in said notice, that from and
         after said date interest will cease to accrue. If less than all the
         Junior Subordinated Debentures are to be redeemed, the notice to the
         Holders of Junior Subordinated Debentures to be redeemed in whole or
         in part shall specify the particular Junior Subordinated Debentures to
         be so redeemed. In case any Junior Subordinated Debenture is to be
         redeemed in part only, the notice that relates to such Junior
         Subordinated Debenture shall state the portion of the principal amount
         thereof to be redeemed, and shall state that on and after the
         redemption date, upon surrender of such Junior Subordinated Debenture,
         a new Junior Subordinated Debenture or Junior Subordinated Debentures
         in principal amount equal to the unredeemed portion thereof shall be
         issued to the Holder.

                  (b) If less than all the Junior Subordinated Debentures are
         to be redeemed, the Company shall give the Trustee at least 45 days'
         notice in advance of the date fixed for redemption as to the aggregate
         principal amount of Junior Subordinated Debentures to be redeemed, and
         thereupon the Trustee shall select, by lot or in such other manner as
         it shall deem appropriate and fair in its discretion and that may
         provide for the selection of a portion or portions (equal to ten
         dollars U.S. ($10) or any integral multiple thereof), the Junior
         Subordinated Debentures to be redeemed and shall thereafter promptly
         notify the Company in writing of the numbers of the Junior
         Subordinated Debentures to be redeemed, in whole or in part.

                  The Company may, if and whenever it shall so elect, by
         delivery of instructions signed on its behalf by its Chief Executive
         Officer, its President or any Vice President, instruct the Trustee or
         any paying agent to call all or any part of the Junior Subordinated
         Debentures for redemption and to give notice of redemption in the
         manner set forth in this Section, such notice to be in the name of the
         Company or in the name of the Trustee or the paying agent, as the
         Trustee or such paying agent may deem advisable. In any case in which
         notice of redemption is to be given by the Trustee or any such paying
         agent, the Company shall deliver or cause to be delivered to, or
         permit to remain with, the Trustee or such paying agent, as the case
         may be, such Securities Register, transfer books or other records, or
         suitable copies or extracts therefrom, sufficient to enable the
         Trustee or such paying agent to give any notice by mail that may be
         required under the provisions of this Section.

         3.05     PAYMENT UPON REDEMPTION.

                  (a) If the giving of notice of redemption shall have been
         completed as above provided, the Junior Subordinated Debentures or
         portions of Junior Subordinated Debentures to be redeemed specified in
         such notice shall become due and payable on the date and at the


                                       17
<PAGE>   24

         place stated in such notice at the Redemption Price (which includes
         interest accrued to the date fixed for redemption) and interest on
         such Junior Subordinated Debentures or portions of Junior Subordinated
         Debentures shall cease to accrue on and after the date fixed for
         redemption, unless the Company shall default in the payment of such
         Redemption Price with respect to any such Junior Subordinated
         Debentures or portions thereof. On presentation and surrender of such
         Junior Subordinated Debentures on or after the date fixed for
         redemption at the place of payment specified in the notice, such
         Junior Subordinated Debentures shall be paid and redeemed at the
         Redemption Price (which includes the interest accrued thereon to the
         date fixed for redemption) (but if the date fixed for redemption is an
         Interest Payment Date, the interest installment payable on such date
         shall be payable to the Registered Holder at the close of business on
         the applicable record date pursuant to Section 2.05(a)).

                  (b) Upon presentation of any Junior Subordinated Debenture
         that is to be redeemed in part only, the Company shall execute and the
         Trustee shall authenticate and the office or agency where the Junior
         Subordinated Debenture is presented shall deliver to the Holder
         thereof, at the expense of the Company, a new Junior Subordinated
         Debenture or Junior Subordinated Debentures of authorized
         denominations in principal amount equal to the unredeemed portion of
         the Junior Subordinated Debenture so presented.

         3.06 NO SINKING FUND. The Junior Subordinated Debentures are not
entitled to the benefit of any sinking fund.

                                   ARTICLE IV
                      EXTENSION OF INTEREST PAYMENT PERIOD

         4.01 EXTENSION OF INTEREST PAYMENT PERIOD. So long as no Event of
Default has occurred and is continuing, the Company shall have the right, at
any time and from time to time during the term of the Junior Subordinated
Debentures, to defer payments of interest by extending the interest payment
period of such Junior Subordinated Debentures for a period not exceeding 20
consecutive quarters (the "Extended Interest Payment Period"), during which
Extended Interest Payment Period no interest shall be due and payable; provided
that no Extended Interest Payment Period may extend beyond the Maturity Date.
To the extent permitted by applicable law, interest, the payment of which has
been deferred because of the extension of the interest payment period pursuant
to this Section 4.01, will bear interest thereon at the Coupon Rate compounded
quarterly for each quarter of the Extended Interest Payment Period ("Compounded
Interest"). At the end of the Extended Interest Payment Period, the Company
shall pay all interest accrued and unpaid on the Junior Subordinated
Debentures, including any Additional Sums and Compounded Interest (together,
"Deferred Interest") that shall be payable to the Holders of the Junior
Subordinated Debentures in whose names the Junior Subordinated Debentures are
registered in the Securities Register on the record date for the Interest
Payment Date coinciding with the end of the Extended Interest Payment Period.
Before the termination of any Extended Interest Payment Period, the Company may
further extend such period, provided that such period together with all such
further extensions thereof shall not exceed 20 consecutive quarters, or extend
beyond the Maturity Date.


                                       18
<PAGE>   25

Upon the termination of any Extended Interest Payment Period and upon the
payment of all Deferred Interest then due, the Company may commence a new
Extended Interest Payment Period, subject to the foregoing requirements. No
interest shall be due and payable during an Extended Interest Payment Period,
except at the end thereof, but the Company may prepay at any time all or any
portion of the interest accrued during an Extended Interest Payment Period.

         4.02     NOTICE OF EXTENSION.

                  (a) If the Property Trustee is the only Registered Holder of
         the Junior Subordinated Debentures at the time the Company selects an
         Extended Interest Payment Period, the Company shall give written
         notice to the Administrative Trustees, the Property Trustee and the
         Trustee of its selection of such Extended Interest Payment Period one
         Business Day before the earlier of (i) the next succeeding date on
         which Distributions are payable, or (ii) the date the Trust is
         required to give notice of the record date, or the date such
         Distributions are payable, to the Preferred Securities holders or to
         the NASDAQ National Market or other applicable self-regulatory
         organization, if any, but in any event at least one Business Day
         before such record date.

                  (b) If the Property Trustee is not the only Holder of the
         Junior Subordinated Debentures at the time the Company selects an
         Extended Interest Payment Period, the Company shall give the Holders
         of the Junior Subordinated Debentures and the Trustee written notice
         of its selection of such Extended Interest Payment Period at least one
         Business Day before the earlier of (i) the next succeeding Interest
         Payment Date, or (ii) the date the Company is required to give notice
         of the record or payment date of such interest payment to the Holders
         of the Junior Subordinated Debentures or to the NASDAQ National Market
         or other applicable self-regulatory organization, if any.

                  (c) The quarter in which any notice is given pursuant to
         paragraph (a) or paragraph (b) of this Section 4.02 shall be counted
         as one of the 20 quarters permitted in the maximum Extended Interest
         Payment Period permitted under Section 4.01.

         4.03     LIMITATION OF TRANSACTIONS DURING EXTENSION.  If (a) the
Company shall exercise its right to defer payment of interest as provided in
Section 4.01; or (b) there shall have occurred any Event of Default, then the
Company shall be subject to the restrictions on payments set forth under
Section 5.06.

                                   ARTICLE V
                      PARTICULAR COVENANTS OF THE COMPANY

         5.01 PAYMENT OF PRINCIPAL AND INTEREST. The Company will duly and
punctually pay or cause to be paid the principal of and interest on the Junior
Subordinated Debentures at the time and place and in the manner provided herein
and established with respect to such Junior Subordinated Debentures.


                                       19
<PAGE>   26

         5.02 MAINTENANCE OF AGENCY. So long as any Junior Subordinated
Debentures remain Outstanding, the Company agrees to maintain an office or
agency in Wilmington, Delaware, or at such other location or locations as may
be designated as provided in this Section 5.02, where (a) Junior Subordinated
Debentures may be presented for payment, (b) Junior Subordinated Debentures may
be presented as hereinabove authorized for registration of transfer and
exchange, and (c) notices and demands to or upon the Company in respect of the
Junior Subordinated Debentures and this Indenture may be given or served, such
designation to continue with respect to such office or agency until the Company
shall, by written notice signed by its Chief Executive Officer, its President
or a Vice President and delivered to the Trustee, designate some other office
or agency for such purposes or any of them. If at any time the Company shall
fail to maintain any such required office or agency or shall fail to furnish
the Trustee with the address thereof, such presentations, notices and demands
may be made or served at the Corporate Trust Office of the Trustee, and the
Company hereby appoints the Trustee as its agent to receive all such
presentations, notices and demands.

         5.03     PAYING AGENTS.

                  (a) If the Company shall appoint one or more paying agents
         for the Junior Subordinated Debentures, other than the Trustee, the
         Company will cause each such paying agent to execute and deliver to
         the Trustee an instrument in which such agent shall agree with the
         Trustee, subject to the provisions of this Section:

                           (i) that it will hold all sums held by it as such
                  agent for the payment of the principal of or interest on the
                  Junior Subordinated Debentures (whether such sums have been
                  paid to it by the Company or by any other obligor) in trust
                  for the benefit of the Persons entitled thereto;

                           (ii) that it will give the Trustee notice of any
                  failure by the Company (or by any other obligor) to make any
                  payment of the principal of or interest on the Junior
                  Subordinated Debentures when the same shall be due and
                  payable;

                           (iii) that it will, at any time during the
                  continuance of any failure referred to in the preceding
                  paragraph (a)(ii) above, upon the written request of the
                  Trustee, forthwith pay to the Trustee all sums so held in
                  trust by such paying agent; and

                           (iv) that it will perform all other duties of paying
                  agent as set forth in this Indenture.

                  (b) If the Company shall act as its own paying agent with
         respect to the Junior Subordinated Debentures, it will on or before
         each due date of the principal of or interest on Junior Subordinated
         Debentures, set aside, segregate and hold in trust for the benefit of
         the Persons entitled thereto a sum sufficient to pay such principal or
         interest so becoming due until such sums shall be paid to such Persons
         or otherwise disposed of as herein provided and


                                       20
<PAGE>   27

         will promptly notify the Trustee of such action, or any failure (by it
         or any other obligor) to take such action. Whenever the Company shall
         have one or more paying agents for the Junior Subordinated Debentures,
         it will, prior to each due date of the principal of or interest on the
         Junior Subordinated Debentures, deposit with the paying agent a sum
         sufficient to pay the principal or interest so becoming due, such sum
         to be held in trust for the benefit of the Persons entitled to such
         principal or interest, and (unless such paying agent is the Trustee)
         the Company will promptly notify the Trustee of this action or failure
         so to act.

                  (c) Notwithstanding anything in this Section to the contrary,
         (i) the agreement to hold sums in trust as provided in this Section is
         subject to the provisions of Section 13.05, and (ii) the Company may
         at any time, for the purpose of obtaining the satisfaction and
         discharge of this Indenture or for any other purpose, pay, or direct
         any paying agent to pay, to the Trustee all sums held in trust by the
         Company or such paying agent, such sums to be held by the Trustee upon
         the same terms and conditions as those upon which such sums were held
         by the Company or such paying agent; and, upon such payment by any
         paying agent to the Trustee, such paying agent shall be released from
         all further liability with respect to such money.

         5.04     APPOINTMENT TO FILL VACANCY IN OFFICE OF TRUSTEE.  The
Company, whenever necessary to avoid or fill a vacancy in the office of
Trustee, will appoint, in the manner provided in Section 9.10, a Trustee, so
that there shall at all times be a Trustee hereunder.

         5.05 COMPLIANCE WITH CONSOLIDATION PROVISIONS. The Company will not,
while any of the Junior Subordinated Debentures remain Outstanding, consolidate
with, or merge into, or merge into itself, or sell or convey all or
substantially all of its property to any other company unless the provisions of
Article XII hereof are complied with.

         5.06 RESTRICTIONS ON CERTAIN PAYMENTS. If at any time (a) there shall
have occurred any event of which the Company has actual knowledge that (i) with
the giving of notice or the lapse of time, or both, would constitute an Event
of Default and (ii) in respect to which the Company shall not have taken
reasonable steps to cure, or (b) the Company shall have given notice of its
election of an Extended Interest Payment Period as provided herein with respect
to the Junior Subordinated Debentures and shall not have rescinded such notice,
or such Extended Interest Payment Period, or any extension thereof, shall be
continuing; or (c) while the Junior Subordinated Debentures are held by the
Trust, the Company shall be in default with respect to its payment of any
obligation under the Preferred Securities Guarantee, then the Company will not
(i) declare or pay any dividends or distributions on, or redeem, purchase,
acquire, or make a liquidation payment with respect to, any of the Company's
capital stock or (ii) make any payment of principal, interest or premium, if
any, on or repay, repurchase or redeem any debt securities of the Company
(including the Junior Subordinated Debentures) that rank pari passu with or
junior in interest to the Junior Subordinated Debentures or make any guarantee
payments with respect to any guarantee by the Company of the debt securities of
any Subsidiary of the Company if such guarantee ranks pari passu or junior in
interest to the Junior Subordinated Debentures (other than (A) dividends or
distributions


                                       21
<PAGE>   28

in common stock, (B) any declaration of a dividend in connection with the
implementation of a shareholders' rights plan, or the issuance of stock under
any such plan in the future or the redemption or repurchase of any such rights
pursuant thereto, (C) payments under the Preferred Securities Guarantee and (D)
purchases of common stock related to the issuance of common stock or rights
under any of the Company's benefit plans for its directors, officers or
employees).

         5.07 COVENANTS AS TO THE TRUST. For so long as the Trust Securities of
the Trust remain outstanding, the Company will (a) maintain 100% direct or
indirect ownership of the Common Securities of the Trust; provided, however,
that any permitted successor of the Company under this Indenture may succeed to
the Company's ownership of the Common Securities, (b) use its reasonable
efforts to cause the Trust (i) to remain a business trust, except in connection
with a distribution of Junior Subordinated Debentures, the redemption of all of
the Trust Securities of the Trust or certain mergers, consolidations or
amalgamations, each as permitted by the Trust Agreement, and (ii) to otherwise
continue not to be treated as an association taxable as a corporation or
partnership for United States federal income tax purposes and (c) to use its
reasonable efforts to cause each Holder of Trust Securities to be treated as
owning an individual undivided beneficial interest in the Junior Subordinated
Debentures.

         If the Junior Subordinated Debentures are to be issued as a Global
Subordinated Debenture in connection with the distribution of the Junior
Subordinated Debentures to the holders of the Preferred Securities issued by
the Trust upon a Dissolution Event, the Company will use its best efforts to
list such Junior Subordinated Debentures on the NASDAQ National Market or on
such other exchange as the Preferred Securities may then be listed.

                                   ARTICLE VI
                       SECURITYHOLDERS' LISTS AND REPORTS
                         BY THE COMPANY AND THE TRUSTEE

         6.01     COMPANY TO FURNISH TRUSTEE NAMES AND ADDRESSES OF
SECURITYHOLDERS. The Company will furnish or cause to be furnished to the
Trustee (a) on each regular record date (as defined in Section 2.05(a)) a list,
in such form as the Trustee may reasonably require, of the names and addresses
of the Holders as of such regular record date, provided that the Company shall
not be obligated to furnish or cause to furnish such list at any time that the
list shall not differ in any respect from the most recent list furnished to the
Trustee by the Company and (b) at such other times as the Trustee may request
in writing within 30 days after the receipt by the Company of any such request,
a list of similar form and content as of a date not more than 15 days prior to
the time such list is furnished; provided, however, that, in either case, no
such list need be furnished if the Trustee shall be the Securities Registrar.


                                       22
<PAGE>   29

         6.02     PRESERVATION OF INFORMATION; COMMUNICATIONS WITH
SECURITYHOLDERS.

                  (a) The Trustee shall preserve, in as current a form as is
         reasonably practicable, all information as to the names and addresses
         of the Holders contained in the most recent list furnished to it as
         provided in Section 6.01 and as to the names and addresses of Holders
         received by the Trustee in its capacity as Securities Registrar (if
         acting in such capacity).

                  (b) The Trustee may destroy any list furnished to it as
         provided in Section 6.01 upon receipt of a new list so furnished.

                  (c) Securityholders may communicate as provided in Section
         312(b) of the Trust Indenture Act with other Securityholders with
         respect to their rights under this Indenture or under the Junior
         Subordinated Debentures.

         6.03     REPORTS BY THE COMPANY.

                  (a) The Company covenants and agrees to file with the
         Trustee, within 15 days after the Company is required to file the same
         with the Commission, copies of the annual reports and of the
         information, documents and other reports (or copies of such portions
         of any of the foregoing as the Commission may from time to time by
         rules and regulations prescribe) that the Company may be required to
         file with the Commission pursuant to Section 13 or Section 15(d) of
         the Exchange Act; or, if the Company is not required to file
         information, documents or reports pursuant to either of such sections,
         then to file with the Trustee and the Commission, in accordance with
         the rules and regulations prescribed from time to time by the
         Commission, such of the supplementary and periodic information,
         documents and reports that may be required pursuant to any applicable
         rules and regulations of the Commission.

                  (b) The Company covenants and agrees to file with the Trustee
         and the Commission, in accordance with the rules and regulations
         prescribed from time to time by the Commission, such additional
         information, documents and reports with respect to compliance by the
         Company with the conditions and covenants provided for in this
         Indenture as may be required from time to time by such rules and
         regulations.

                  (c) The Company covenants and agrees to transmit by mail,
         first class postage prepaid, or reputable overnight delivery service
         that provides for evidence of receipt, to the Securityholders, as
         their names and addresses appear upon the Securities Register, within
         30 days after the filing thereof with the Trustee, such summaries of
         any information, documents and reports required to be filed by the
         Company pursuant to subsections (a) and (b) of this Section as may be
         required by rules and regulations prescribed from time to time by the
         Commission.


                                       23
<PAGE>   30

         6.04     REPORTS BY THE TRUSTEE.

                  (a) Beginning July 31, 2000, on or before July 31 in each
         year in which any of the Junior Subordinated Debentures are
         Outstanding, the Trustee shall transmit by mail, first class postage
         prepaid, to the Securityholders, as their names and addresses appear
         upon the Securities Register, a brief report dated as of the preceding
         December 31, if and to the extent required under Section 313(a) of the
         Trust Indenture Act.

                  (b) The Trustee shall comply with Section 313(b) and 313(c)
         of the Trust Indenture Act.

                  (c) A copy of each such report shall, at the time of such
         transmission to Securityholders, be filed by the Trustee with the
         Company, and also with the Commission.

                                  ARTICLE VII
                          REMEDIES OF THE TRUSTEE AND
                      SECURITYHOLDERS ON EVENT OF DEFAULT

         7.01     EVENTS OF DEFAULT.

                  (a) Whenever used herein, "Event of Default" means any one or
         more of the following events that has occurred and is continuing:

                           (i) the Company defaults in the payment of any
                  installment of interest upon any of the Junior Subordinated
                  Debentures, as and when the same shall become due and
                  payable, and continuance of such default for a period of 30
                  days; provided, however, that a valid extension of an
                  interest payment period by the Company in accordance with the
                  terms of this Indenture shall not constitute a default in the
                  payment of interest for this purpose;

                           (ii) the Company defaults in the payment of the
                  principal of any of the Junior Subordinated Debentures as and
                  when the same shall become due and payable whether at
                  maturity, upon redemption, by declaration or otherwise;

                           (iii) the Company fails to observe or perform any
                  other of its covenants or agreements hereunder with respect
                  to the Junior Subordinated Debentures for a period of 90 days
                  after the date on which written notice of such failure,
                  requiring the same to be remedied and stating that such
                  notice is a "Notice of Default" hereunder, shall have been
                  given to the Company by the Trustee, by registered or
                  certified mail, or to the Company and the Trustee by the
                  Holders of at least 25% in principal amount of the Junior
                  Subordinated Debentures at the time Outstanding;


                                       24
<PAGE>   31

                           (iv) the Company pursuant to or within the meaning
                  of any Bankruptcy Law (A) commences a voluntary case, (B)
                  consents to the entry of an order for relief against it in an
                  involuntary case, (C) consents to the appointment of a
                  custodian of it or for all or substantially all of its
                  property or (D) makes a general assignment for the benefit of
                  its creditors;

                           (v) a court of competent jurisdiction enters an
                  order under any Bankruptcy Law that (A) is for relief against
                  the Company in an involuntary case, (B) appoints a custodian
                  of the Company for all or substantially all of its property,
                  or (C) orders the liquidation of the Company, and the order
                  or decree remains unstayed and in effect for 90 days; or

                           (vi) in the event Junior Subordinated Debentures are
                  issued to the Trust or a trustee of the Trust in connection
                  with the issuance of Trust Securities by the Trust, the Trust
                  shall have voluntarily or involuntarily dissolved, wound up
                  its business or otherwise terminated its existence, except in
                  connection with (A) the distribution of Junior Subordinated
                  Debentures to holders of Trust Securities in liquidation of
                  their interests in the Trust, (B) the redemption of all of
                  the outstanding Trust Securities of the Trust or (C) certain
                  mergers, consolidations or amalgamations, each as permitted
                  by the Trust Agreement.

                  (b) In each and every such case, unless the principal of all
         the Junior Subordinated Debentures shall have already become due and
         payable, either the Trustee or the Holders of not less than 25% in
         aggregate principal amount of the Junior Subordinated Debentures then
         Outstanding hereunder, by notice in writing to the Company (and to the
         Trustee if given by such Securityholders) may declare the principal of
         all the Junior Subordinated Debentures to be due and payable
         immediately, and upon any such declaration the same shall become and
         shall be immediately due and payable, notwithstanding anything
         contained in this Indenture or in the Junior Subordinated Debentures
         to the contrary.

                  (c) At any time after the principal of the Junior
         Subordinated Debentures shall have been so declared due and payable,
         and before any judgment or decree for the payment of the moneys due
         shall have been obtained or entered as hereinafter provided, the
         Holders of a majority in aggregate principal amount of the Junior
         Subordinated Debentures then Outstanding, by written notice to the
         Company and the Trustee, may rescind and annul such declaration and
         its consequences if: (i) the Company has paid or deposited with the
         Trustee a sum sufficient to pay all matured installments of interest
         upon all the Junior Subordinated Debentures and the principal of any
         and all Junior Subordinated Debentures that shall have become due
         otherwise than by acceleration (with interest upon such principal and,
         to the extent that such payment is enforceable under applicable law,
         upon overdue installments of interest, at the rate per annum expressed
         in the Junior Subordinated Debentures to the date of such payment or
         deposit) and the amount payable to the Trustee under Section 9.06, and
         (ii) any and all Events of Default under this Indenture, other than
         the nonpayment of


                                       25
<PAGE>   32

         principal on Junior Subordinated Debentures that shall not have become
         due by their terms, shall have been remedied or waived as provided in
         Section 7.06. Should the Holders fail to annul such declaration and
         waive such default, then the holders of a majority in aggregate
         Liquidation Amount of the Preferred Securities shall have such right.

                  No such rescission and annulment shall extend to or shall
         affect any subsequent default or impair any right consequent thereon.

                  (d) In case the Trustee shall have proceeded to enforce any
         right with respect to Junior Subordinated Debentures under this
         Indenture and such proceedings shall have been discontinued or
         abandoned because of such rescission or annulment or for any other
         reason or shall have been determined adversely to the Trustee, then
         and in every such case the Company and the Trustee shall be restored
         respectively to their former positions and rights hereunder, and all
         rights, remedies and powers of the Company and the Trustee shall
         continue as though no such proceedings had been taken.

         7.02     COLLECTION OF INDEBTEDNESS AND SUITS FOR ENFORCEMENT BY
TRUSTEE.

                  (a) The Company covenants that (i) in case it shall default
         in the payment of any installment of interest on any of the Junior
         Subordinated Debentures as and when the same shall have become due and
         payable, and such default shall have continued for a period of 90
         Business Days, or (ii) in case it shall default in the payment of the
         principal of any of the Junior Subordinated Debentures when the same
         shall have become due and payable, whether upon maturity of the Junior
         Subordinated Debentures or upon redemption or upon declaration or
         otherwise, then, upon demand of the Trustee, the Company will pay to
         the Trustee, for the benefit of the Holders of the Junior Subordinated
         Debentures, the whole amount that then shall have become due and
         payable on all such Junior Subordinated Debentures for principal or
         interest, or both, as the case may be, with interest upon the overdue
         principal and (to the extent that payment of such interest is
         enforceable under applicable law and, if the Junior Subordinated
         Debentures are held by the Trust or a trustee of the Trust, without
         duplication of any other amounts paid by the Trust or trustee in
         respect thereof) upon overdue installments of interest at the rate per
         annum expressed in the Junior Subordinated Debentures; and, in
         addition thereto, such further amount as shall be sufficient to cover
         the costs and expenses of collection, and the amount payable to the
         Trustee under Section 9.06.

                  (b) If the Company shall fail to pay such amounts forthwith
         upon such demand, the Trustee, in its own name and as trustee of an
         express trust, shall be entitled and empowered to institute any action
         or proceedings at law or in equity for the collection of the sums so
         due and unpaid, and may prosecute any such action or proceeding to
         judgment or final decree, and may enforce any such judgment or final
         decree against the Company or other obligor upon the Junior
         Subordinated Debentures and collect the moneys adjudged or


                                       26
<PAGE>   33

         decreed to be payable in the manner provided by law out of the
         property of the Company or other obligor upon the Junior Subordinated
         Debentures, wherever situated.

                  (c) In case of any receivership, insolvency, liquidation,
         bankruptcy, reorganization, readjustment, arrangement, composition or
         judicial proceedings affecting the Company or the creditors or
         property of either, the Trustee shall have power to intervene in such
         proceedings and take any action therein that may be permitted by the
         court and shall (except as may be otherwise provided by law) be
         entitled to file such proofs of claim and other papers and documents
         as may be necessary or advisable in order to have the claims of the
         Trustee and of the Holders of Junior Subordinated Debentures allowed
         for the entire amount due and payable by the Company under this
         Indenture at the date of institution of such proceedings and for any
         additional amount that may become due and payable by the Company after
         such date, and to collect and receive any moneys or other property
         payable or deliverable on any such claim, and to distribute the same
         after the deduction of the amount payable to the Trustee under Section
         9.06; and any receiver, assignee or trustee in bankruptcy or
         reorganization is hereby authorized by each of the Holders to make
         such payments to the Trustee, and, in the event that the Trustee shall
         consent to the making of such payments directly to such
         Securityholders, to pay to the Trustee any amount due it under Section
         9.06.

                  (d) All rights of action and of asserting claims under this
         Indenture may be enforced by the Trustee without the possession of any
         of the Junior Subordinated Debentures, or the production thereof at
         any trial or other proceeding relative thereto, and any such suit or
         proceeding instituted by the Trustee shall be brought in its own name
         as trustee of an express trust, and any recovery of judgment shall,
         after provision for payment to the Trustee of any amounts due under
         Section 9.06, be for the ratable benefit of the Holders of the Junior
         Subordinated Debentures.

                  In case of an Event of Default hereunder, the Trustee may in
         its discretion proceed to protect and enforce the rights vested in it
         by this Indenture by such appropriate judicial proceedings as the
         Trustee shall deem most effectual to protect and enforce any of such
         rights, either at law or in equity or in bankruptcy or otherwise,
         whether for the specific enforcement of any covenant or agreement
         contained in this Indenture or in aid of the exercise of any power
         granted in this Indenture, or to enforce any other legal or equitable
         right vested in the Trustee by this Indenture or by law.

                  Nothing contained herein shall be deemed to authorize the
         Trustee to authorize or consent to or accept or adopt on behalf of any
         Securityholder any plan of reorganization, arrangement, adjustment or
         composition affecting the Junior Subordinated Debentures or the rights
         of any Holder thereof or to authorize the Trustee to vote in respect
         of the claim of any Securityholder in any such proceeding.

         7.03 APPLICATION OF MONEYS COLLECTED. Any moneys collected by the
Trustee pursuant to this Article with respect to the Junior Subordinated
Debentures shall be applied


                                       27
<PAGE>   34

in the following order, at the date or dates fixed by the Trustee and, in case
of the distribution of such moneys on account of principal or interest, upon
presentation of the Junior Subordinated Debentures, and notation thereon the
payment, if only partially paid, and upon surrender thereof if fully paid:

                  FIRST, to the payment of costs and expenses of collection and
         of all amounts payable to the Trustee under Section 9.06;

                  SECOND, to the payment of all Senior and Subordinated Debt of
         the Company if and to the extent required by Article XVI; and

                  THIRD, to the payment of the amounts then due and unpaid upon
         Junior Subordinated Debentures for principal and interest, in respect
         of which or for the benefit of which such money has been collected,
         ratably, without preference or priority of any kind, according to the
         amounts due and payable on such Junior Subordinated Debentures for
         principal and interest, respectively.

         7.04 LIMITATION ON SUITS. No Holder shall have any right by virtue of
or by availing any provision of this Indenture to institute any suit, action or
proceeding in equity or at law upon or under or with respect to this Indenture
or for the appointment of a receiver or trustee, or for any other remedy
hereunder, unless (a) such Holder previously shall have given to the Trustee
written notice of an Event of Default and of the continuance thereof; (b) the
Holders of not less than 25% in aggregate principal amount of the Junior
Subordinated Debentures then Outstanding shall have made written request upon
the Trustee to institute such action, suit or proceeding in its own name as
trustee hereunder; (c) such Holder or Holders shall have offered to the Trustee
such reasonable indemnity as it may require against the costs, expenses and
liabilities to be incurred therein or thereby; and (d) the Trustee for 60 days
after its receipt of such notice, request and offer of indemnity shall have
failed to institute any such action, suit or proceeding; and (e) during such
60-day period, the Holders of a majority in principal amount of the Junior
Subordinated Debentures do not give the Trustee a direction inconsistent with
the request.

         Notwithstanding any other provisions of this Indenture to the
contrary, the right of any Holder to receive payment of the principal of and
interest on the Junior Subordinated Debentures on or after the respective due
dates (or in the case of redemption, on the redemption date), or to institute
suit for the enforcement of any such payment on or after such respective dates
or redemption date, shall not be impaired or affected without the consent of
such Holder; and by accepting a Junior Subordinated Debenture hereunder it is
expressly understood, intended and covenanted by the Holder thereof with every
other such Holder and the Trustee, that no one or more Holders shall have any
right in any manner whatsoever by virtue of or by availing any provision of
this Indenture to affect, disturb or prejudice the rights of any other Holders,
or to obtain or seek to obtain priority over or preference to any such other
Holders, or to enforce any right under this Indenture, except in the manner
herein provided and for the equal, ratable and common benefit of all Holders of
Junior Subordinated Debentures. For the protection and enforcement of the
provisions of this Section, each


                                       28
<PAGE>   35

and every Securityholder and the Trustee shall be entitled to such relief as
can be given either at law or in equity.

         7.05     RIGHTS AND REMEDIES CUMULATIVE; DELAY OR OMISSION NOT
WAIVER.

                  (a) Except as otherwise provided in Section 7.02, all powers
         and remedies given by this Article to the Trustee or to the
         Securityholders shall, to the extent permitted by law, be deemed
         cumulative and not exclusive of any other powers and remedies
         available to the Trustee or the Holders of the Junior Subordinated
         Debentures, by judicial proceedings or otherwise, to enforce the
         performance or observance of the covenants and agreements contained in
         this Indenture or otherwise established with respect to such Junior
         Subordinated Debentures.

                  (b) No delay or omission of the Trustee or of any Holder of
         any of the Junior Subordinated Debentures to exercise any right or
         power accruing upon any Event of Default occurring and continuing as
         aforesaid shall impair any such right or power, or shall be construed
         to be a waiver of any such default or on acquiescence therein; and,
         subject to the provisions of Section 7.04, every power and remedy
         given by this Article or by law to the Trustee or the Securityholders
         may be exercised from time to time, and as often as shall be deemed
         expedient, by the Trustee or by the Securityholders.

         7.06 CONTROL BY SECURITYHOLDERS. The Holders of a majority in
aggregate principal amount of the Junior Subordinated Debentures at the time
Outstanding, determined in accordance with Section 10.04, shall have the right
to direct the time, method and place of conducting any proceeding for any
remedy available to the Trustee, or exercising any trust or power conferred on
the Trustee; provided, however, that such direction shall not be in conflict
with any rule of law or with this Indenture. Subject to the provisions of
Section 9.01, the Trustee shall have the right to decline to follow any such
direction if the Trustee in good faith shall, by a Responsible Officer or
Officers of the Trustee, determine that the proceeding so directed would
involve the Trustee in personal liability. The Holders of a majority in
aggregate principal amount of the Junior Subordinated Debentures at the time
Outstanding affected thereby, determined in accordance with Section 10.04, may
on behalf of the Holders of all of the Junior Subordinated Debentures waive any
past default in the performance of any of the covenants contained herein and
its consequences, except (a) a default in the payment of the principal of or
interest on any of the Junior Subordinated Debentures as and when the same
shall become due by its terms otherwise than by acceleration (unless such
default has been cured and a sum sufficient to pay all matured installments of
interest and principal has been deposited with the Trustee in accordance with
Section 7.01(c)), (b) a default in the covenants contained in Section 5.06 or
(c) in respect of a covenant or provision hereof which under Article XI cannot
be modified or amended without the consent of the Holder of each Outstanding
Junior Subordinated Debenture affected; provided, however, that if the Junior
Subordinated Debentures are held by the Trust or a Trustee of the Trust, such
waiver or modification to such waiver shall not be effective until the Holders
of a majority in Liquidation Amount of Trust


                                       29
<PAGE>   36

Securities of the Trust shall have consented to such waiver or modification to
such waiver; provided further, that if the consent of the Holder of each
Outstanding Junior Subordinated Debenture is required, such waiver shall not be
effective until each Holder of the Trust Securities of the Trust shall have
consented to such waiver. Upon any such waiver, the default covered thereby
shall be deemed to be cured for all purposes of this Indenture and the Company,
the Trustee and the Holders of the Junior Subordinated Debentures shall be
restored to their former positions and rights hereunder, respectively; but no
such waiver shall extend to any subsequent or other default or impair any right
consequent thereon.

         7.07 UNDERTAKING TO PAY COSTS. All parties to this Indenture agree,
and each Holder of any Junior Subordinated Debentures by such Holder's
acceptance thereof shall be deemed to have agreed, that any court may in its
discretion require, in any suit for the enforcement of any right or remedy
under this Indenture, or in any suit against the Trustee for any action taken
or omitted by it as Trustee, the filing by any party litigant in such suit of
an undertaking to pay the costs of such suit, and that such court may in its
discretion assess reasonable costs, including reasonable attorneys' fees,
against any party litigant in such suit, having due regard to the merits and
good faith of the claims or defenses made by such party litigant; but the
provisions of this Section shall not apply to any suit instituted by the
Trustee, to any suit instituted by any Securityholder, or group of
Securityholders, holding more than 10% in aggregate principal amount of the
Outstanding Junior Subordinated Debentures, or to any suit instituted by any
Securityholder for the enforcement of the payment of the principal of or
interest on the Junior Subordinated Debentures on or after the due dates
thereof.

                                  ARTICLE VIII
            FORM OF JUNIOR SUBORDINATED DEBENTURE AND ORIGINAL ISSUE

         8.01 FORM OF JUNIOR SUBORDINATED DEBENTURE. The Junior Subordinated
Debenture and the Trustee's Certificate of Authentication to be endorsed
thereon are to be substantially in the forms contained as Exhibit A to this
Indenture, attached hereto and incorporated herein by reference.

         8.02 ORIGINAL ISSUE OF JUNIOR SUBORDINATED DEBENTURES. Junior
Subordinated Debentures in the aggregate principal amount of $__________ may,
upon execution of this Indenture, be executed by the Company and delivered to
the Trustee for authentication, and the Trustee shall thereupon authenticate
and deliver the Junior Subordinated Debentures to or upon the written order of
the Company, signed by its Chairman, its Vice Chairman, its Chief Executive
Officer, its President or any Vice President, without any further action by the
Company.


                                       30
<PAGE>   37

                                   ARTICLE IX
                             CONCERNING THE TRUSTEE

         9.01     CERTAIN DUTIES AND RESPONSIBILITIES OF THE TRUSTEE.

                  (a) The Trustee, prior to the occurrence of an Event of
         Default and after the curing of all Events of Default that may have
         occurred, shall undertake to perform with respect to the Junior
         Subordinated Debentures such duties and only such duties as are
         specifically set forth in this Indenture, and no implied covenants
         shall be read into this Indenture against the Trustee. In case an
         Event of Default has occurred (that has not been cured or waived), the
         Trustee shall exercise such of the rights and powers vested in it by
         this Indenture, and use the same degree of care and skill in their
         exercise as a prudent person would exercise or use under the
         circumstances in the conduct of his own affairs.

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

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

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

                                    (B) in the absence of bad faith on the part
                           of the Trustee, the Trustee may conclusively rely,
                           as to the truth of the statements and the
                           correctness of the opinions expressed therein, upon
                           any certificates or opinions furnished to the
                           Trustee and conforming to the requirements of this
                           Indenture; but in the case of any such certificates
                           or opinions that by any provision hereof are
                           specifically required to be furnished to the
                           Trustee, the Trustee shall be under a duty to
                           examine the same to determine whether or not they
                           conform to the requirement of this Indenture;

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

                           (iii) the Trustee shall not be liable with respect
                  to any action taken or omitted to be taken by it in good
                  faith in accordance with the direction of the Holders of not
                  less than a majority in principal amount of the Junior
                  Subordinated Debentures


                                       31
<PAGE>   38

                  at the time Outstanding relating to the time, method and
                  place of conducting any proceeding for any remedy available
                  to the Trustee, or exercising any trust or power conferred
                  upon the Trustee under this Indenture; and

                           (iv) none of the provisions contained in this
                  Indenture shall require the Trustee to expend or risk its own
                  funds or otherwise incur personal financial liability in the
                  performance of any of its duties or in the exercise of any of
                  its rights or powers, if there is reasonable ground for
                  believing that the repayment of such funds or liability is
                  not reasonably assured to it under the terms of this
                  Indenture or adequate indemnity against such risk is not
                  reasonably assured to it.

                  (c) Within 90 days after actual knowledge by a Responsible
         Officer of the Trustee of the occurrence of any default hereunder with
         respect to the Securities, the Trustee shall transmit by mail to all
         Holders of Securities, as their names and addresses appear in the
         Securities Register, notice of such default, unless such default shall
         have been cured or waived; provided, however, that, except in the case
         of a default in the payment of the principal of (or premium, if any)
         or interest (including any Additional Interest) on any Security, the
         Trustee shall be protected in withholding such notice if and so long
         as the board of directors, the executive committee or a trust
         committee of directors and/or Responsible Officers of the Trustee in
         good faith determines that the withholding of such notice is in the
         interests of the Holders of Securities. For the purpose of this
         Section 9.01, the term "default" means any event that is, or after
         notice or lapse of time or both would become, an Event of Default with
         respect to the Securities.

         9.02 CERTAIN RIGHTS OF TRUSTEE. Except as otherwise provided in
Section 9.01:

                  (a) the Trustee may rely and shall be protected in acting or
         refraining from acting upon any resolution, certificate, statement,
         instrument, opinion, report, notice, request, consent, order,
         approval, bond, security or other paper or document believed by it to
         be genuine and to have been signed or presented by the proper party or
         parties;

                  (b) any request, direction, order or demand of the Company
         mentioned herein shall be sufficiently evidenced by a Board Resolution
         or an instrument signed in the name of the Company by the Chief
         Executive Officer, the President or any Vice President and by the
         Secretary or an Assistant Secretary or the Chief Accounting Officer
         thereof (unless other evidence in respect thereof is specifically
         prescribed herein);

                  (c) the Trustee may consult with counsel and the written
         advice of such counsel or any Opinion of Counsel shall be full and
         complete authorization and protection in respect of any action taken
         or suffered or omitted hereunder in good faith and in reliance
         thereon;


                                       32
<PAGE>   39

                  (d) the Trustee shall be under no obligation to exercise any
         of the rights or powers vested in it by this Indenture at the request,
         order or direction of any of the Securityholders, pursuant to the
         provisions of this Indenture, unless such Securityholders shall have
         offered to the Trustee reasonable security or indemnity against the
         costs, expenses and liabilities that may be incurred therein or
         thereby; nothing contained herein shall, however, relieve the Trustee
         of the obligation, upon the occurrence of an Event of Default (that
         has not been cured or waived) to exercise such of the rights and
         powers vested in it by this Indenture, and to use the same degree of
         care and skill in their exercise as a prudent person would exercise or
         use under the circumstances in the conduct of his own affairs;

                  (e) the Trustee shall not be liable for any action taken or
         omitted to be taken by it in good faith and believed by it to be
         authorized or within the discretion or rights or powers conferred upon
         it by this Indenture;

                  (f) the Trustee shall not be bound to make any investigation
         into the facts or matters stated in any resolution, certificate,
         statement, instrument, opinion, report, notice, request, consent,
         order, approval, bond, security or other papers or documents, unless
         requested in writing so to do by the Holders of not less than a
         majority in principal amount of the Outstanding Junior Subordinated
         Debentures (determined as provided in Section 10.04); provided,
         however, that if the payment within a reasonable time to the Trustee
         of the costs, expenses or liabilities likely to be incurred by it in
         the making of such investigation is, in the opinion of the Trustee,
         not reasonably assured to the Trustee by the security afforded to it
         by the terms of this Indenture, the Trustee may require reasonable
         indemnity against such costs, expenses or liabilities as a condition
         to so proceeding. The reasonable expense of every such examination
         shall be paid by the Company or, if paid by the Trustee, shall be
         repaid by the Company upon demand; and

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

         9.03     TRUSTEE NOT RESPONSIBLE FOR RECITALS OR ISSUANCE OF THE
JUNIOR SUBORDINATED DEBENTURES.

                  (a) The recitals contained herein and in the Junior
         Subordinated Debentures shall be taken as the statements of the
         Company and the Trustee assumes no responsibility for the correctness
         of the same.

                  (b) The Trustee makes no representations as to the validity
         or sufficiency of this Indenture or of the Junior Subordinated
         Debentures.


                                       33
<PAGE>   40

                  (c) The Trustee shall not be accountable for the use or
         application by the Company of any of the Junior Subordinated
         Debentures or of the proceeds of such Junior Subordinated Debentures,
         or for the use or application of any moneys paid over by the Trustee
         in accordance with any provision of this Indenture, or for the use or
         application of any moneys received by any paying agent other than the
         Trustee.

         9.04     MAY HOLD JUNIOR SUBORDINATED DEBENTURES.  The Trustee or any
paying agent or Securities Registrar, in its individual or any other capacity,
may become the owner or pledgee of Junior Subordinated Debentures with the same
rights it would have if it were not Trustee, paying agent or Securities
Registrar.

         9.05 MONEYS HELD IN TRUST. Subject to the provisions of Section 13.05,
all moneys received by the Trustee shall, until used or applied as herein
provided, be held in trust for the purposes for which they were received, but
need not be segregated from other funds except to the extent required by law.
The Trustee shall be under no liability for interest on any moneys received by
it hereunder except such as it may agree with the Company to pay thereon.

         9.06     COMPENSATION AND REIMBURSEMENT.

                  (a) The Company covenants and agrees to pay to the Trustee,
         and the Trustee shall be entitled to, such reasonable compensation
         (which shall not be limited by any provision of law in regard to the
         compensation of a trustee of an express trust), as the Company and the
         Trustee may from time to time agree in writing, for all services
         rendered by it in the execution of the trusts hereby created and in
         the exercise and performance of any of the powers and duties hereunder
         of the Trustee, and, except as otherwise expressly provided herein,
         the Company will pay or reimburse the Trustee upon its request for all
         reasonable expenses, disbursements and advances incurred or made by
         the Trustee in accordance with any of the provisions of this Indenture
         (including the reasonable compensation and the expenses and
         disbursements of its counsel and of all Persons not regularly in its
         employ) except any such expense, disbursement or advance as may arise
         from its negligence or bad faith. The Company also covenants to
         indemnify the Trustee (and its officers, agents, directors and
         employees) for, and to hold it harmless against, any loss, liability
         or expense incurred without negligence or bad faith on the part of the
         Trustee and arising out of or in connection with the acceptance or
         administration of this trust, including the costs and expenses of
         defending itself against any claim of liability in the premises.

                  (b) The obligations of the Company under this Section to
         compensate and indemnify the Trustee and to pay or reimburse the
         Trustee for expenses, disbursements and advances shall constitute
         additional indebtedness hereunder. Such additional indebtedness shall
         be secured by a lien prior to that of the Junior Subordinated
         Debentures upon all property and funds held or collected by the
         Trustee as such, except funds held in trust for the benefit of the
         Holders of the Junior Subordinated Debentures.


                                       34
<PAGE>   41

                  (c) When the Trustee incurs expenses or renders services
         after an Event of Default specified in Section 7.01(iv), (v) or (vi)
         occurs, the expenses and the compensation for the services are
         intended to constitute expenses of administration under the Bankruptcy
         Reform Act of 1978 or any successor statute.

         9.07 RELIANCE ON OFFICERS' CERTIFICATE. Except as otherwise provided
in Section 9.01, whenever in the administration of the provisions of this
Indenture the Trustee shall deem it necessary or desirable that a matter be
proved or established prior to taking or suffering or omitting to take any
action hereunder, such matter (unless other evidence in respect thereof be
herein specifically prescribed) may, in the absence of negligence or bad faith
on the part of the Trustee, be deemed to be conclusively proved and established
by an Officers' Certificate delivered to the Trustee and such certificate, in
the absence of negligence or bad faith on the part of the Trustee, shall be
full warrant to the Trustee for any action taken, suffered or omitted to be
taken by it under the provisions of this Indenture upon the faith thereof.

         9.08 DISQUALIFICATION; CONFLICTING INTERESTS. If the Trustee has or
shall acquire any "conflicting interest" within the meaning of Section 310(b)
of the Trust Indenture Act, the Trustee and the Company shall in all respects
comply with the provisions of Section 310(b) of the Trust Indenture Act.

         9.09 CORPORATE TRUSTEE REQUIRED; ELIGIBILITY. There shall at all times
be a Trustee with respect to the Junior Subordinated Debentures issued
hereunder which shall at all times be a corporation organized and doing
business under the laws of the United States of America or any state or
territory thereof or of the District of Columbia, or a corporation or other
Person permitted to act as trustee by the Commission, authorized under such
laws to exercise corporate trust powers, having a combined capital and surplus
of at least $50,000,000 and subject to supervision or examination by federal,
state, territorial, or District of Columbia authority. If such corporation
publishes reports of condition at least annually, pursuant to law or to the
requirements of the aforesaid supervising or examining authority, then for the
purposes of this Section, the combined capital and surplus of such corporation
shall be deemed to be its combined capital and surplus as set forth in its most
recent report of condition so published. No Affiliate of the Company may serve
as Trustee. In case at any time the Trustee shall cease to be eligible in
accordance with the provisions of this Section, the Trustee shall resign
immediately in the manner and with the effect specified in Section 9.10.

         9.10     RESIGNATION AND REMOVAL; APPOINTMENT OF SUCCESSOR.

                  (a) The Trustee, or any successor hereafter appointed, may at
         any time resign by giving written notice thereof to the Company and by
         transmitting notice of resignation by mail, first class postage
         prepaid, to the Securityholders, as their names and addresses appear
         upon the Securities Register. Upon receiving such notice of
         resignation, the Company shall promptly appoint a successor trustee by
         written instrument, in duplicate, executed by order of the Board of
         Directors, one copy of which instrument shall be delivered to the
         resigning


                                       35
<PAGE>   42

         Trustee and one copy to the successor trustee. If no successor trustee
         shall have been so appointed and have accepted appointment within 30
         days after the mailing of such notice of resignation, the resigning
         Trustee may petition any court of competent jurisdiction for the
         appointment of a successor trustee, or any Securityholder who has been
         a bona fide Holder of Junior Subordinated Debentures for at least six
         months may, subject to the provisions of Section 7.07, on behalf of
         such Securityholder and all other Holders, petition any such court for
         the appointment of a successor trustee. Such court may thereupon,
         after such notice, if any, as it may deem proper and prescribe,
         appoint a successor trustee.

                  (b) In case at any time any one of the following shall occur:

                           (i) the Trustee shall fail to comply with the
                  provisions of Section 9.08 after written request therefor by
                  the Company or by any Securityholder who has been a bona fide
                  Holder of Junior Subordinated Debentures for at least six
                  months; or

                           (ii) the Trustee shall cease to be eligible in
                  accordance with the provisions of Section 9.09 and shall fail
                  to resign after written request therefor by the Company or by
                  any such Securityholder; or

                           (iii) the Trustee shall become incapable of acting,
                  or shall be adjudged a bankrupt or insolvent, or commence a
                  voluntary bankruptcy proceeding, or a receiver of the Trustee
                  or of its property shall be appointed or consented to, or any
                  public officer shall take charge or control of the Trustee or
                  of its property or affairs for the purpose of rehabilitation,
                  conservation or liquidation, then, in any such case, the
                  Company may remove the Trustee and appoint a successor
                  trustee by written instrument, in duplicate, executed by
                  order of the Board of Directors, one copy of which instrument
                  shall be delivered to the Trustee so removed and one copy to
                  the successor trustee, or, subject to the provisions of
                  Section 7.07, unless the Trustee's duty to resign is stayed
                  as provided herein, any Securityholder who has been a bona
                  fide Holder of Junior Subordinated Debentures for at least
                  six months may, on behalf of that Holder and all other
                  Holders, petition any court of competent jurisdiction for the
                  removal of the Trustee and the appointment of a successor
                  trustee. Such court may thereupon after such notice, if any,
                  as it may deem proper and prescribe, remove the Trustee and
                  appoint a successor trustee.

                  (c) The Holders of a majority in aggregate principal amount
         of the Junior Subordinated Debentures at the time Outstanding may at
         any time remove the Trustee by so notifying the Trustee and the
         Company and may appoint a successor Trustee with the consent of the
         Company.

                  (d) Any resignation or removal of the Trustee and appointment
         of a successor trustee pursuant to any of the provisions of this
         Section shall become effective upon acceptance of appointment by the
         successor trustee as provided in Section 9.11.


                                       36
<PAGE>   43

         9.11     ACCEPTANCE OF APPOINTMENT BY SUCCESSOR.

                  (a) In case of the appointment hereunder of a successor
         trustee, every such successor trustee so appointed shall execute,
         acknowledge and deliver to the Company and to the retiring Trustee an
         instrument accepting such appointment, and thereupon the resignation
         or removal of the retiring Trustee shall become effective and such
         successor trustee, without any further act, deed or conveyance, shall
         become vested with all the rights, powers, trusts and duties of the
         retiring Trustee; but, on the request of the Company or the successor
         trustee, such retiring Trustee shall, upon payment of its charges,
         execute and deliver an instrument transferring to such successor
         trustee all the rights, powers, and trusts of the retiring Trustee and
         shall duly assign, transfer and deliver to such successor trustee all
         property and money held by such retiring Trustee hereunder.

                  (b) Upon request of any such successor trustee, the Company
         shall execute any and all instruments for more fully and certainly
         vesting in and confirming to such successor trustee all such rights,
         powers and trusts referred to in paragraph (a) of this Section.

                  (c) No successor trustee shall accept its appointment unless
         at the time of such acceptance such successor trustee shall be
         qualified and eligible under this Article.

                  (d) Upon acceptance of appointment by a successor trustee as
         provided in this Section, the Company shall transmit notice of the
         succession of such trustee hereunder by mail, first class postage
         prepaid, to the Securityholders, as their names and addresses appear
         upon the Securities Register. If the Company fails to transmit such
         notice within ten days after acceptance of appointment by the
         successor trustee, the successor trustee shall cause such notice to be
         transmitted at the expense of the Company.

         9.12     MERGER, CONVERSION, CONSOLIDATION OR SUCCESSION TO
BUSINESS. Any corporation into which the Trustee may be merged or converted or
with which it may be consolidated, or any corporation resulting from any
merger, conversion or consolidation to which the Trustee shall be a party, or
any corporation succeeding to the corporate trust business of the Trustee,
shall be the successor of the Trustee hereunder, provided that such corporation
shall be qualified and eligible under the provisions of this Article IX,
without the execution or filing of any paper or any further act on the part of
any of the parties hereto, anything herein to the contrary notwithstanding. In
case any Junior Subordinated Debentures shall have been authenticated, but not
delivered, by the Trustee then in office, any successor by merger, conversion
or consolidation to such authenticating Trustee may adopt such authentication
and deliver the Junior Subordinated Debentures so authenticated with the same
effect as if such successor Trustee had itself authenticated such Junior
Subordinated Debentures.

         9.13     PREFERENTIAL COLLECTION OF CLAIMS AGAINST THE COMPANY.
The Trustee shall comply with Section 311(a) of the Trust Indenture Act,
excluding any creditor relationship described in Section 311(b) of the Trust
Indenture Act. A Trustee who has resigned or


                                       37
<PAGE>   44

been removed shall be subject to Section 311(a) of the Trust Indenture Act to
the extent included therein.

         9.14 APPOINTMENT OF AUTHENTICATING AGENT. At any time when any of the
Junior Subordinated Debentures remain Outstanding, the Trustee may appoint an
Authenticating Agent or Agents which shall be authorized to act on behalf of
the Trustee to authenticate Junior Subordinated Debentures issued upon original
issuance, exchange, registration of transfer or partial redemption thereof or
pursuant to Section 2.08, and Junior Subordinated Debentures so authenticated
shall be entitled to the benefits of this Indenture and shall be valid and
obligatory for all purposes as if authenticated by the Trustee hereunder.
Wherever reference is made in this Indenture to the authentication and delivery
of Junior Subordinated Debentures by the Trustee or the Trustee's certificate
of authentication, such reference shall be deemed to include authentication and
delivery on behalf of the Trustee by an Authenticating Agent and a certificate
of authentication executed on behalf of the Trustee by an Authenticating Agent.
Each Authenticating Agent shall be acceptable to the Company and shall at all
times be a corporation organized and doing business under the laws of the
United States of America, any state thereof or the District of Columbia,
authorized under such laws to act as Authenticating Agent, having a combined
capital and surplus of not less than $50,000,000 and subject to supervision or
examination by federal or state authority. If such Authenticating Agent
publishes reports of condition at least annually, pursuant to law or to the
requirements of such supervision or examining authority, for the purposes of
this Section, the combined capital and surplus of such Authenticating Agent
shall be deemed to be its combined capital and surplus as set forth in its most
recent report of condition so published. If at any time an Authenticating Agent
shall cease to be eligible in accordance with the provisions of this Section,
such Authenticating Agent shall resign immediately in the manner and with the
effect specified in this Section.

         Any corporation into which an Authenticating Agent may be merged or
converted or with which it may be consolidated, or any corporation resulting
from any merger, conversion or consolidation to which such Authenticating Agent
shall be a party, or any corporation succeeding to the corporate agency or
corporate trust business of an Authenticating Agent, shall continue to be an
Authenticating Agent, provided such corporation shall be otherwise eligible
under this Section, without the execution or filing of any paper or any further
act on the part of the Trustee or the Authenticating Agent.

         An Authenticating Agent may resign at any time by giving written
notice thereof to the Trustee and to the Company. The Trustee may at any time
terminate the agency of an Authenticating Agent by giving written notice
thereof to such Authenticating Agent and to the Company. Upon receiving such
notice of resignation or upon such termination, or in case at any time such
Authenticating Agent shall cease to be eligible in accordance with the
provisions of this Section, the Trustee may appoint a successor Authenticating
Agent which shall be acceptable to the Company and shall mail written notice of
such appointment by first class mail, postage prepaid, to all Securityholders
as their names and addresses appear in the Securities Register. Any successor
Authenticating Agent upon acceptance of its appointment hereunder shall become
vested with all


                                       38
<PAGE>   45

the rights, powers and duties of its predecessor hereunder, with the like
effect as if originally named as an Authenticating Agent herein. No successor
Authenticating Agent shall be appointed unless eligible under the provisions of
this Section.

         The Trustee agrees to pay to each Authenticating Agent from time to
time reasonable compensation for its services under this Section, and the
Trustee shall be entitled to be reimbursed for such payments, subject to the
provisions of Section 9.06.

         If an appointment is made pursuant to this Section, the Junior
Subordinated Debentures may have endorsed thereon, in lieu of the form of
certificate of authentication set forth in Section 8.01, a certificate of
authentication in the following form:

         "This is one of the Junior Subordinated Debentures described in the
within mentioned Indenture."


                                   ------------------------------------,
                                   as Trustee

                             By

                                   ------------------------------------,
                                   as Authenticating Agent

                             By

                                   ------------------------------------,
                                   Authorized Signature

                                   ARTICLE X
                         CONCERNING THE SECURITYHOLDERS

         10.01 EVIDENCE OF ACTION BY SECURITYHOLDERS.  Whenever in this
Indenture it is provided that the Holders of a majority or specified percentage
in aggregate principal amount of the Junior Subordinated Debentures may take any
action (including the making of any demand or request, the giving of any notice,
consent or waiver or the taking of any other action), the fact that at the time
of taking any such action the Holders of such majority or specified percentage
have joined therein may be evidenced by any instrument or any number of
instruments of similar tenor executed by such Holders in Person or by agent or
proxy appointed in writing.

         If the Company shall solicit from the Securityholders any request,
demand, authorization, direction, notice, consent, waiver or other action, the
Company may, at its option, as evidenced by an Officers' Certificate, fix in
advance a record date for the determination of Securityholders entitled to give
such request, demand, authorization, direction, notice, consent, waiver or
other action, but the Company shall have no obligation to do so. If such a
record date is fixed, such request, demand, authorization, direction, notice,
consent, waiver or other action may be given before or after the record date,
but only the Securityholders of record at the close of business on the record
date shall


                                       39
<PAGE>   46

be deemed to be Securityholders for the purposes of determining whether
Securityholders of the requisite proportion of Outstanding Junior Subordinated
Debentures have authorized or agreed or consented to such request, demand,
authorization, direction, notice, consent, waiver or other action, and for that
purpose the Outstanding Junior Subordinated Debentures shall be computed as of
the record date; provided, however, that no such authorization, agreement or
consent by such Securityholders on the record date shall be deemed effective
unless it shall become effective pursuant to the provisions of this Indenture
not later than six months after the record date.

         10.02 PROOF OF EXECUTION BY SECURITYHOLDERS. Subject to the provisions
of Section 6.01, proof of the execution of any instrument by a Securityholder
(such proof will not require notarization) or his agent or proxy and proof of
the holding by any Person of any of the Junior Subordinated Debentures shall be
sufficient if made in the following manner:

                  (a) The fact and date of the execution by any such Person of
         any instrument may be proved in any reasonable manner acceptable to
         the Trustee.

                  (b) The ownership of Junior Subordinated Debentures shall be
         proved by the Securities Register or by a certificate of the
         Securities Registrar thereof.

                  (c) The Trustee may require such additional proof of any
         matter referred to in this Section as it shall deem necessary.

         10.03 WHO MAY BE DEEMED OWNERS. Prior to the due presentment for
registration of transfer of any Junior Subordinated Debenture, the Company, the
Trustee, any paying agent and any Securities Registrar may deem and treat the
Person in whose name such Junior Subordinated Debenture shall be registered
upon the books of the Company as the absolute owner of such Junior Subordinated
Debenture (whether or not such Junior Subordinated Debenture shall be overdue
and notwithstanding any notice of ownership or writing thereon made by anyone
other than the Securities Registrar) for the purpose of receiving payment of or
on account of the principal of and (subject to Section 2.03) interest on such
Junior Subordinated Debenture and for all other purposes; and neither the
Company nor the Trustee nor any paying agent nor any Securities Registrar shall
be affected by any notice to the contrary.

         10.04 CERTAIN JUNIOR SUBORDINATED DEBENTURES OWNED BY COMPANY
DISREGARDED. In determining whether the Holders of the requisite aggregate
principal amount of Junior Subordinated Debentures have concurred in any
direction, consent or waiver under this Indenture, the Junior Subordinated
Debentures that are owned by the Company or any other obligor on the Junior
Subordinated Debentures or by any Person directly or indirectly controlling or
controlled by or under common control with the Company or any other obligor on
the Junior Subordinated Debentures shall be disregarded and deemed not to be
Outstanding for the purpose of any such determination, except that for the
purpose of determining whether the Trustee shall be protected in relying on any
such direction, consent or waiver, only Junior Subordinated Debentures that a
Responsible Officer of the Trustee actually knows are so owned shall be so


                                       40
<PAGE>   47

disregarded. The Junior Subordinated Debentures so owned that have been pledged
in good faith may be regarded as Outstanding for the purposes of this Section,
if the pledgee shall establish to the satisfaction of the Trustee the pledgee's
right with respect to such Junior Subordinated Debentures and that the pledgee
is not a Person directly or indirectly controlling or controlled by or under
direct or indirect common control with the Company or any such other obligor.
In case of a dispute as to such right, any decision by the Trustee taken upon
the advice of counsel shall be full protection to the Trustee.

         10.05 ACTIONS BINDING ON FUTURE SECURITYHOLDERS.  At any time prior to
(but not after) the evidencing to the Trustee, as provided in Section 10.01, of
the taking of any action by the Holders of the majority or percentage in
aggregate principal amount of the Junior Subordinated Debentures specified in
this Indenture in connection with such action, any Holder who is shown by the
evidence to have consented to such action may, by filing written notice with the
Trustee, and upon proof of holding as provided in Section 10.02, revoke such
action so far as concerns such Holder's Junior Subordinated Debentures. Except
as aforesaid any such action taken by the Holder shall be conclusive and binding
upon such Holder and upon all future Holders and owners of such Holder's Junior
Subordinated Debentures, and of any Junior Subordinated Debentures issued in
exchange therefor, on registration of transfer thereof or in place thereof,
irrespective of whether or not any notation in regard thereto is made upon such
Junior Subordinated Debentures. Any action taken by the Holders of the majority
or percentage in aggregate principal amount of the Junior Subordinated
Debentures specified in this Indenture in connection with such action shall be
conclusively binding upon the Company, the Trustee and the Holders of all the
Junior Subordinated Debentures.

                                   ARTICLE XI
                            SUPPLEMENTAL INDENTURES

         11.01 SUPPLEMENTAL INDENTURES WITHOUT THE CONSENT OF SECURITYHOLDERS.
In addition to any supplemental indenture otherwise authorized by this
Indenture, the Company and the Trustee may from time to time and at any time
enter into an indenture or indentures supplemental hereto (which shall conform
to the provisions of the Trust Indenture Act as then in effect), without the
consent of the Securityholders, for one or more of the following purposes:

                  (a) to cure any ambiguity, defect, or inconsistency herein,
         or in the Junior Subordinated Debentures, provided that any such
         action does not materially adversely affect the interests of the
         Holders or the holders of the Preferred Securities so long as they
         remain outstanding;

                  (b)      to comply with Article XII;

                  (c) to provide for uncertificated Junior Subordinated
         Debentures in addition to or in place of certificated Junior
         Subordinated Debentures;


                                       41
<PAGE>   48

                  (d) to add to the covenants of the Company for the benefit of
         the Holders or to surrender any right or power herein conferred upon
         the Company;

                  (e) to add to, delete from, or revise the conditions,
         limitations, and restrictions on the authorized amount, terms, or
         purposes of issue, authentication, and delivery of Junior Subordinated
         Debentures, as herein set forth;

                  (f) to make any change that does not adversely affect the
         rights of any Securityholder in any material respect; or

                  (g) to establish the form of any certifications required to
         be furnished pursuant to the terms of this Indenture or to add to the
         rights of the Holders.

         The Trustee is hereby authorized to join with the Company in the
execution of any such supplemental indenture, and to make any further
appropriate agreements and stipulations that may be therein contained, but the
Trustee shall not be obligated to enter into any such supplemental indenture
that affects the Trustee's own rights, duties or immunities under this
Indenture or otherwise.

         Any supplemental indenture authorized by the provisions of this
Section may be executed by the Company and the Trustee without the consent of
the Holders of any of the Junior Subordinated Debentures at the time
Outstanding, notwithstanding any of the provisions of Section 11.02.

         11.02 SUPPLEMENTAL INDENTURES WITH CONSENT OF SECURITYHOLDERS. With the
consent (evidenced as provided in Section 10.01) of the Holders of not less than
a majority in aggregate principal amount of the Junior Subordinated Debentures
at the time Outstanding, the Company, when authorized by Board Resolutions, and
the Trustee may from time to time and at any time enter into an indenture or
indentures supplemental hereto (which shall conform to the provisions of the
Trust Indenture Act as then in effect) for the purpose of adding any provisions
to or changing in any manner or eliminating any of the provisions of this
Indenture or of any supplemental indenture or of modifying in any manner not
covered by Section 11.01 the rights of the Holders of the Junior Subordinated
Debentures under this Indenture; provided, however, that no such supplemental
indenture shall without the consent of the Holders of each Junior Subordinated
Debenture then Outstanding, (a) change (except as expressly provided herein
pursuant to Section 2.02) the stated maturity of the Junior Subordinated
Debentures or reduce the principal amount thereof; or reduce the rate or extend
(except as expressly provided herein pursuant to Section 4.01) the time of
payment of interest thereon; or (b) reduce the percentage of principal amount of
Junior Subordinated Debentures, the Holders of which are required to consent to
any such supplemental indenture; provided, further, that if the Junior
Subordinated Debentures are held by the Trust or a trustee of the Trust, such
supplemental indenture shall not be effective until the holders of a majority in
aggregate Liquidation Amount of Preferred Securities shall have consented to
such supplemental indenture; provided further, that if the consent of the Holder
of each Outstanding


                                       42
<PAGE>   49

Junior Subordinated Debenture is required, such supplemental indenture shall
not be effective until each Holder of the Trust Securities shall have consented
to such supplemental indenture.

         It shall not be necessary for the consent of the Securityholders to
approve the particular form of any proposed supplemental indenture, but it
shall be sufficient if such consent shall approve the substance thereof.

         11.03 EFFECT OF SUPPLEMENTAL INDENTURES.  Upon the execution of any
supplemental indenture pursuant to the provisions of this Article or of Section
12.01, this Indenture shall be and be deemed to be modified and amended in
accordance therewith.

         11.04 JUNIOR SUBORDINATED DEBENTURES AFFECTED BY SUPPLEMENTAL
INDENTURES. Junior Subordinated Debentures, affected by a supplemental
indenture, authenticated and delivered after the execution of such supplemental
indenture pursuant to the provisions of this Article or of Section 12.01, may
bear a notation in form approved by the Company, as to any matter provided for
in such supplemental indenture. If the Company shall so determine, new Junior
Subordinated Debentures so modified as to conform, in the opinion of the Board
of Directors, to any modification of this Indenture contained in any such
supplemental indenture may be prepared by the Company, authenticated by the
Trustee and delivered in exchange for the Junior Subordinated Debentures then
Outstanding.

         11.05 EXECUTION OF SUPPLEMENTAL INDENTURES. Upon the request of the
Company, accompanied by Board Resolutions authorizing the execution of any such
supplemental indenture, and upon the filing with the Trustee of evidence of the
consent of Securityholders required to consent thereto as aforesaid, the
Trustee shall join with the Company in the execution of such supplemental
indenture unless such supplemental indenture affects the Trustee's own rights,
duties or immunities under this Indenture or otherwise, in which case the
Trustee may in its discretion but shall not be obligated to enter into such
supplemental indenture. The Trustee, subject to the provisions of Section 9.01,
may receive an Opinion of Counsel as conclusive evidence that any supplemental
indenture executed pursuant to this Article is authorized or permitted by, and
conforms to, the terms of this Article and that it is proper for the Trustee
under the provisions of this Article to join in the execution thereof.

         Promptly after the execution by the Company and the Trustee of any
supplemental indenture pursuant to the provisions of this Section, the Company
shall transmit by mail, first class postage prepaid, a notice, setting forth in
general terms the substance of such supplemental indenture, to the
Securityholders as their names and addresses appear upon the Securities
Register. Any failure of the Company to mail such notice, or any defect
therein, shall not, however, in any way impair or affect the validity of any
such supplemental indenture.


                                       43
<PAGE>   50

                                  ARTICLE XII
                             SUCCESSOR CORPORATION

         12.01 COMPANY MAY CONSOLIDATE, ETC. The Company shall not consolidate
with or merge into any other Person or convey, transfer or lease its properties
and assets substantially as an entirety to any Person, and no Person shall
consolidate with or merge into the Company or convey, transfer or lease its
properties and assets substantially as an entirety to the Company, unless (a)
in case the Company consolidates with or merges into another Person or conveys
or transfers its properties and assets substantially as an entirety to any
Person, the successor Person is organized under the laws of the United States
or any state or the District of Columbia, and such successor Person expressly
assumes the Company's obligations on the Junior Subordinated Debentures issued
under this Indenture; (b) immediately after giving effect thereto, no Event of
Default, and no event which, after notice or lapse of time or both, would
become an Event of Default, shall have occurred and be continuing; and (c) such
successor Person expressly assumes the due and punctual performance and
observance of all the covenants and conditions of this Indenture to be kept and
performed by the Company by executing and delivering a supplemental indenture
in form and substance satisfactory to the Trustee.

         12.02 SUCCESSOR SUBSTITUTED.

                  (a) In case of any such consolidation, merger, sale,
         conveyance, transfer or other disposition and upon the assumption by
         the successor Person by supplemental indenture, executed and delivered
         to the Trustee and satisfactory in form to the Trustee, of the due and
         punctual payment of the principal of and interest on all of the Junior
         Subordinated Debentures Outstanding and the due and punctual
         performance of all of the covenants and conditions of this Indenture
         to be performed by the Company, such successor Person shall succeed to
         and be substituted for the Company, with the same effect as if it had
         been named as the Company herein, and thereupon the predecessor
         corporation shall be relieved of all obligations and covenants under
         this Indenture and the Junior Subordinated Debentures.

                  (b) In case of any such consolidation, merger, sale,
         conveyance, transfer or other disposition such changes in phraseology
         and form (but not in substance) may be made in the Junior Subordinated
         Debentures thereafter to be issued as may be appropriate.

         12.03 EVIDENCE OF CONSOLIDATION, ETC., TO TRUSTEE. The Trustee,
subject to the provisions of Section 9.01, may receive an Opinion of Counsel as
conclusive evidence that any such consolidation, merger, sale, conveyance,
transfer or other disposition, and any such assumption, comply with the
provisions of this Article.


                                       44
<PAGE>   51

                                  ARTICLE XIII
                           SATISFACTION AND DISCHARGE

         13.01 SATISFACTION AND DISCHARGE OF INDENTURE. If at any time: (a) the
Company shall have delivered to the Trustee for cancellation all Junior
Subordinated Debentures theretofore authenticated (other than any Junior
Subordinated Debentures that shall have been destroyed, lost or stolen and that
shall have been replaced or paid as provided in Section 2.08) and Junior
Subordinated Debentures for whose payment money or Governmental Obligations
have theretofore been deposited in trust or segregated and held in trust by the
Company (and thereupon repaid to the Company or discharged from such trust, as
provided in Section 13.05); or (b) all such Junior Subordinated Debentures not
theretofore delivered to the Trustee for cancellation shall have become due and
payable, or are by their terms to become due and payable within one year or are
to be called for redemption within one year under arrangements satisfactory to
the Trustee for the giving of notice of redemption, and the Company shall
deposit or cause to be deposited with the Trustee as trust funds the entire
amount in moneys or Governmental Obligations sufficient or a combination
thereof sufficient, in the opinion of a nationally recognized firm of
independent public accountants expressed in a written certification thereof
delivered to the Trustee, to pay at maturity or upon redemption all Junior
Subordinated Debentures not theretofore delivered to the Trustee for
cancellation, including principal and interest due or to become due to such
date of maturity or date fixed for redemption, as the case may be, and if the
Company shall also pay or cause to be paid all other sums payable hereunder by
the Company; then this Indenture shall thereupon cease to be of further effect
except for the provisions of Sections 2.02, 2.03, 2.04, 2.05, 4.01, 4.02, 4.03
and 9.10, that shall survive until the date of maturity or redemption date, as
the case may be, and Sections 9.06 and 13.05, that shall survive to such date
and thereafter, and the Trustee, on demand of the Company and at the cost and
expense of the Company, shall execute proper instruments acknowledging
satisfaction of and discharging this Indenture.

         13.02 DISCHARGE OF OBLIGATIONS. If at any time all such Junior
Subordinated Debentures not theretofore delivered to the Trustee for
cancellation or that have not become due and payable as described in Section
13.01 shall have been paid by the Company by depositing irrevocably with the
Trustee, as trust funds, moneys or an amount of Governmental Obligations
sufficient to pay at maturity or upon redemption all such Junior Subordinated
Debentures not theretofore delivered to the Trustee for cancellation, including
principal and interest due or to become due to such date of maturity or date
fixed for redemption, as the case may be, and if the Company shall also pay or
cause to be paid all other sums payable hereunder by the Company, then after
the date such moneys or Governmental Obligations, as the case may be, are
deposited with the Trustee the obligations of the Company under this Indenture
shall cease to be of further effect except for the provisions of Sections 2.02,
2.03, 2.04, 2.05, 4.01, 4.02, 4.03, 9.06, 9.10 and 13.05 hereof that shall
survive until such Junior Subordinated Debentures shall mature and be paid.
Thereafter, Sections 9.06 and 13.05 shall survive.

         13.03 DEPOSITED MONEYS TO BE HELD IN TRUST. All moneys or Governmental
Obligations deposited with the Trustee pursuant to Sections 13.01 or 13.02
shall be held in trust and


                                       45
<PAGE>   52

shall be available for payment as due, either directly or through any paying
agent (including the Company acting as its own paying agent), to the Holders of
the Junior Subordinated Debentures for the payment or redemption of which such
moneys or Governmental Obligations have been deposited with the Trustee.

         13.04 PAYMENT OF MONEYS HELD BY PAYING AGENTS. In connection with the
satisfaction and discharge of this Indenture all moneys or Governmental
Obligations then held by any paying agent under the provisions of this
Indenture shall, upon demand of the Company, be paid to the Trustee and
thereupon such paying agent shall be released from all further liability with
respect to such moneys or Governmental Obligations.

         13.05 REPAYMENT TO COMPANY. Any moneys or Governmental Obligations
deposited with any paying agent or the Trustee, or then held by the Company in
trust for payment of principal of or interest on the Junior Subordinated
Debentures that are not applied but remain unclaimed by the Holders of such
Junior Subordinated Debentures for at least two years after the date upon which
the principal of or interest on such Junior Subordinated Debentures shall have
respectively become due and payable, shall be repaid to the Company on the
second annual anniversary of when such payment was originally due or (if then
held by the Company) shall be discharged from such trust; and thereupon the
paying agent and the Trustee shall be released from all further liability with
respect to such moneys or Governmental Obligations, and the Holder of any of
the Junior Subordinated Debentures entitled to receive such payment shall
thereafter, as an unsecured general creditor, look only to the Company for the
payment thereof.

                                  ARTICLE XIV
                           IMMUNITY OF INCORPORATORS,
                      STOCKHOLDERS, OFFICERS AND DIRECTORS

         14.01 NO RECOURSE. No recourse under or upon any obligation, covenant
or agreement of this Indenture, or of any Junior Subordinated Debenture, or for
any claim based thereon or otherwise in respect thereof, shall be had against
any incorporator, stockholder, officer or director as such, past, present or
future, of the Company or of any predecessor or successor corporation, either
directly or through the Company or any such predecessor or successor
corporation, whether by virtue of any constitution, statute or rule of law, or
by the enforcement of any assessment or penalty or otherwise; it being
expressly understood that this Indenture and the obligations issued hereunder
are solely corporate obligations, and that no such personal liability whatever
shall attach to, or is or shall be incurred by, the incorporators,
stockholders, officers or directors as such, of the Company or of any
predecessor or successor corporation, or any of them, because of the creation
of the indebtedness hereby authorized, or under or by reason of the
obligations, covenants or agreements contained in this Indenture or in any of
the Junior Subordinated Debentures or implied therefrom; and that any and all
such personal liability of every name and nature, either at common law or in
equity or by constitution or statute, of, and any and all such rights and
claims against, every such incorporator, stockholder, officer or director as
such, because of the creation of the indebtedness hereby authorized, or under
or by reason of the obligations, covenants or agreements


                                       46
<PAGE>   53

contained in this Indenture or in any of the Junior Subordinated Debentures or
implied therefrom, are hereby expressly waived and released as a condition of,
and as a consideration for, the execution of this Indenture and the issuance of
such Junior Subordinated Debentures.

                                   ARTICLE XV
                            MISCELLANEOUS PROVISIONS

         15.01 EFFECT ON SUCCESSORS AND ASSIGNS. All the covenants,
stipulations, promises and agreements in this Indenture contained by or on
behalf of the Company or the Trustee shall bind their respective successors and
assigns, whether so expressed or not.

         15.02 ACTIONS BY SUCCESSOR. Any act or proceeding by any provision of
this Indenture authorized or required to be done or performed by any board,
committee or officer of the Company shall and may be done and performed with
like force and effect by the corresponding board, committee or officer of any
corporation that shall at the time be the lawful sole successor of the Company.

         15.03 SURRENDER OF COMPANY POWERS. The Company by instrument in
writing executed by authority of two-thirds of its Board of Directors and
delivered to the Trustee may surrender any of the powers reserved to the
Company, and thereupon such power so surrendered shall terminate both as to the
Company and as to any successor corporation.

         15.04 NOTICES. Except as otherwise expressly provided herein any
notice or demand that by any provision of this Indenture is required or
permitted to be given or served by the Trustee or by the Holders of Junior
Subordinated Debentures to or on the Company may be given or served by being
deposited first class postage prepaid in a post-office letterbox addressed
(until another address is filed in writing by the Company with the Trustee), as
follows: c/o Enterbank Holdings, Inc., 150 North Meramec, Clayton, Missouri
63105, Attention: Chief Executive Officer. Any notice, election, request or
demand by the Company or any Securityholder to or upon the Trustee shall be
deemed to have been sufficiently given or made, for all purposes, if given or
made in writing at the Corporate Trust Office of the Trustee.

         15.05 GOVERNING LAW. This Indenture and each Junior Subordinated
Debenture shall be deemed to be a contract made under the internal laws of the
State of Missouri and for all purposes shall be construed in accordance with
the laws of said state, provided that the immunities and the standard of care
of the Trustee shall be governed by Delaware law.

         15.06 TREATMENT OF JUNIOR SUBORDINATED DEBENTURES AS DEBT. It is
intended that the Junior Subordinated Debentures will be treated as indebtedness
and not as equity for federal income tax purposes. The provisions of this
Indenture shall be interpreted to further this intention.


                                       47
<PAGE>   54

         15.07    COMPLIANCE CERTIFICATES AND OPINIONS.

                  (a) Upon any application or demand by the Company to the
         Trustee to take any action under any of the provisions of this
         Indenture, the Company shall furnish to the Trustee an Officers'
         Certificate stating that all conditions precedent provided for in this
         Indenture relating to the proposed action have been complied with and
         an Opinion of Counsel stating that in the opinion of such counsel all
         such conditions precedent have been complied with, except that in the
         case of any such application or demand as to which the furnishing of
         such documents is specifically required by any provision of this
         Indenture relating to such particular application or demand, no
         additional certificate or opinion need be furnished.

                  (b) Every certificate or opinion delivered to the Trustee
         with respect to compliance with a condition or covenant in this
         Indenture shall include (i) a statement that the Person making such
         certificate or opinion has read such covenant or condition; (ii) a
         brief statement as to the nature and scope of the examination or
         investigation upon which the statements or opinions contained in such
         certificate or opinion are based; (iii) a statement that, in the
         opinion of such Person, such Person has made such examination or
         investigation as is necessary to enable such Person to express an
         informed opinion as to whether or not such covenant or condition has
         been complied with; and (iv) a statement as to whether or not, in the
         opinion of such Person, such condition or covenant has been complied
         with.

         15.08 PAYMENTS ON BUSINESS DAYS. In any case where the date of
maturity of interest or principal of the Junior Subordinated Debentures or the
date of redemption of the Junior Subordinated Debentures shall not be a
Business Day, then payment of interest or principal will be made on the next
succeeding Business Day (without any additional interest or other payment in
respect of any such delay), except that, if such Business Day is in the next
succeeding calendar year, such payment shall be made on the immediately
preceding Business Day, in each case with the same force and effect as if made
on the date such payment was originally payable.

         15.09 CONFLICT WITH TRUST INDENTURE ACT. If and to the extent that any
provision of this Indenture limits, qualifies or conflicts with the duties
imposed by Sections 310 to 317, inclusive, of the Trust Indenture Act, such
imposed duties shall control.

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

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


                                       48
<PAGE>   55

         15.12 ASSIGNMENT. The Company will have the right at all times to
assign any of its respective rights or obligations under this Indenture to a
direct or indirect wholly owned Subsidiary of the Company, provided that, in
the event of any such assignment, the Company will remain liable for all such
obligations. Subject to the foregoing, this Indenture is binding upon and
inures to the benefit of the parties thereto and their respective successors
and assigns. This Indenture may not otherwise be assigned by the parties
hereto.

         15.13 ACKNOWLEDGMENT OF RIGHTS. The Company acknowledges that, with
respect to any Junior Subordinated Debentures held by the Trust or a trustee of
the Trust, if the Property Trustee of the Trust fails to enforce its rights
under this Indenture as the Holder of the Junior Subordinated Debentures held
as the assets of the Trust, any holder of Preferred Securities may institute
legal proceedings directly against the Company to enforce such Property
Trustee's rights under this Indenture without first instituting any legal
proceedings against such Property Trustee or any other Person or entity.
Notwithstanding the foregoing, if an Event of Default has occurred and is
continuing and such event is attributable to the failure of the Company to pay
interest or principal on the Junior Subordinated Debentures on the date such
interest or principal is otherwise payable (or in the case of redemption, on
the redemption date), the Company acknowledges that a holder of Preferred
Securities may directly institute a proceeding for enforcement of payment to
such holder of the principal of or interest on the Junior Subordinated
Debentures having a principal amount equal to the aggregate Liquidation Amount
of the Preferred Securities of such holder on or after the respective due date
specified in the Junior Subordinated Debentures. This Section 15.13 may not be
amended without the prior written consent of the holders of all of the
Preferred Securities.

                                  ARTICLE XVI
                SUBORDINATION OF JUNIOR SUBORDINATED DEBENTURES

         16.01 AGREEMENT TO SUBORDINATE. The Company covenants and agrees, and
each Holder of Junior Subordinated Debentures issued hereunder by such Holder's
acceptance thereof likewise covenants and agrees, that all Junior Subordinated
Debentures shall be issued subject to the provisions of this Article XVI; and
each Holder, whether upon original issue or upon transfer or assignment
thereof, accepts and agrees to be bound by such provisions.

         The payment by the Company of the principal of and interest on all
Junior Subordinated Debentures issued hereunder shall, to the extent and in the
manner hereinafter set forth, be subordinated and junior in right of payment to
the prior payment in full of all Senior and Subordinated Debt, whether
outstanding at the date of this Indenture or thereafter incurred.

         No provision of this Article XVI shall prevent the occurrence of any
default or Event of Default hereunder.

         16.02 DEFAULT ON SENIOR AND SUBORDINATED DEBT. In the event and during
the continuation of any default by the Company in the payment of principal,
premium, interest or any


                                       49
<PAGE>   56

other payment due on any Senior and Subordinated Debt of the Company or in the
event that the maturity of any Senior and Subordinated Debt of the Company has
been accelerated because of a default, then, in either case, no payment shall
be made by the Company with respect to the principal of or interest on the
Junior Subordinated Debentures.

         In the event that, notwithstanding the foregoing, any payment shall be
received by the Trustee when such payment is prohibited by the preceding
paragraph of this Section 16.02, such payment shall be held in trust for the
benefit of, and shall be paid over or delivered to, the holders of Senior and
Subordinated Debt or their respective representatives, or to the trustee or
trustees under any indenture pursuant to which any of such Senior and
Subordinated Debt may have been issued, as their respective interests may
appear, but only to the extent that the holders of the Senior and Subordinated
Debt (or their representative or representatives or a trustee) notify the
Trustee in writing within 90 days of such payment of the amounts then due and
owing on the Senior and Subordinated Debt and only the amounts specified in
such notice to the Trustee shall be paid to the holders of Senior and
Subordinated Debt.

         16.03 LIQUIDATION; DISSOLUTION; BANKRUPTCY. Upon any payment by the
Company or distribution of assets of the Company of any kind or character,
whether in cash, property or securities, to creditors upon any dissolution or
winding-up or liquidation or reorganization of the Company, whether voluntary
or involuntary or in bankruptcy, insolvency, receivership or other proceedings,
all amounts due upon all Senior and Subordinated Debt of the Company shall
first be paid in full, or payment thereof provided for in money in accordance
with its terms, before any payment is made by the Company on account of the
principal or interest on the Junior Subordinated Debentures; and upon any such
dissolution or winding-up or liquidation or reorganization, any payment by the
Company, or distribution of assets of the Company of any kind or character,
whether in cash, property or securities, to which the Holders or the Trustee
would be entitled to receive from the Company, except for the provisions of
this Article XVI, shall be paid by the Company or by any receiver, trustee in
bankruptcy, liquidating trustee, agent or other Person making such payment or
distribution, or by the Holders or by the Trustee under the Indenture if
received by them or it, directly to the holders of Senior and Subordinated Debt
of the Company (pro rata to such holders on the basis of the respective amounts
of Senior and Subordinated Debt held by such holders, as calculated by the
Company) or their representative or representatives, or to the trustee or
trustees under any indenture pursuant to which any instruments evidencing such
Senior and Subordinated Debt may have been issued, as their respective
interests may appear, to the extent necessary to pay such Senior and
Subordinated Debt in full, in money or money's worth, after giving effect to
any concurrent payment or distribution to or for the holders of such Senior and
Subordinated Debt, before any payment or distribution is made to the Holders or
to the Trustee.

         In the event that, notwithstanding the foregoing, any payment or
distribution of assets of the Company of any kind or character, whether in
cash, property or securities, prohibited by the foregoing, shall be received by
the Trustee before all Senior and Subordinated Debt of the Company is paid in
full, or provision is made for such payment in money in accordance with its
terms, such payment or distribution shall be held in trust for the benefit of
and shall be paid over or delivered to


                                       50
<PAGE>   57

the holders of such Senior and Subordinated Debt or their representative or
representatives, or to the trustee or trustees under any indenture pursuant to
which any instruments evidencing such Senior and Subordinated Debt may have
been issued, and their respective interests may appear, as calculated by the
Company, for application to the payment of all Senior and Subordinated Debt of
the Company, as the case may be, remaining unpaid to the extent necessary to
pay such Senior and Subordinated Debt in full in money in accordance with its
terms, after giving effect to any concurrent payment or distribution to or for
the benefit of the holders of such Senior and Subordinated Debt.

         For purposes of this Article XVI, the words "cash, property or
securities" shall not be deemed to include shares of stock of the Company as
reorganized or readjusted, or securities of the Company or any other
corporation provided for by a plan of reorganization or readjustment, the
payment of which is subordinated at least to the extent provided in this
Article XVI with respect to the Junior Subordinated Debentures to the payment
of all Senior and Subordinated Debt of the Company, as the case may be, that
may at the time be outstanding, provided that (a) such Senior and Subordinated
Debt is assumed by the new corporation, if any, resulting from any such
reorganization or readjustment, and (b) the rights of the holders of such
Senior and Subordinated Debt are not, without the consent of such holders,
altered by such reorganization or readjustment. The consolidation of the
Company with, or the merger of the Company into, another corporation or the
liquidation or dissolution of the Company following the conveyance or transfer
of its property as an entirety, or substantially as an entirety, to another
corporation upon the terms and conditions provided for in Article XII of this
Indenture shall not be deemed a dissolution, winding-up, liquidation or
reorganization for the purposes of this Section 16.03 if such other corporation
shall, as a part of such consolidation, merger, conveyance or transfer, comply
with the conditions stated in Article XII of this Indenture. Nothing in Section
16.02 or in this Section 16.03 shall apply to claims of, or payments to, the
Trustee under or pursuant to Section 9.06 of this Indenture.

         16.04 SUBROGATION. Subject to the payment in full of all Senior and
Subordinated Debt of the Company, the rights of the Holders of the Junior
Subordinated Debentures shall be subrogated to the rights of the holders of
such Senior and Subordinated Debt to receive payments or distributions of cash,
property or securities of the Company, as the case may be, applicable to such
Senior and Subordinated Debt until the principal of and interest on the Junior
Subordinated Debentures shall be paid in full; and, for the purposes of such
subrogation, no payments or distributions to the holders of such Senior and
Subordinated Debt of any cash, property or securities to which the Holders of
the Junior Subordinated Debentures or the Trustee would be entitled except for
the provisions of this Article XVI, and no payment over pursuant to the
provisions of this Article XVI to or for the benefit of the holders of such
Senior and Subordinated Debt by Holders of the Junior Subordinated Debentures
or the Trustee, shall, as between the Company, its creditors other than holders
of Senior and Subordinated Debt of the Company, and the Holders of the Junior
Subordinated Debentures, be deemed to be a payment by the Company to or on
account of such Senior and Subordinated Debt. It is understood that the
provisions of this Article XVI are and are intended solely for the purposes of
defining the relative rights of the Holders of the Junior Subordinated
Debentures, on the one hand, and the holders of such Senior and Subordinated
Debt on the other hand.


                                       51
<PAGE>   58

         Nothing contained in this Article XVI or elsewhere in this Indenture
or in the Junior Subordinated Debentures is intended to or shall impair, as
between the Company, its creditors other than the holders of Senior and
Subordinated Debt of the Company, and the Holders of the Junior Subordinated
Debentures, the obligation of the Company, which is absolute and unconditional,
to pay to the Holders of the Junior Subordinated Debentures the principal of
and interest on the Junior Subordinated Debentures as and when the same shall
become due and payable in accordance with their terms, or is intended to or
shall affect the relative rights of the Holders of the Junior Subordinated
Debentures and creditors of the Company, other than the holders of Senior and
Subordinated Debt of the Company, nor shall anything herein or therein prevent
the Trustee or the Holder of any Junior Subordinated Debenture from exercising
all remedies otherwise permitted by applicable law upon default under this
Indenture, subject to the rights, if any, under this Article XVI of the holders
of such Senior and Subordinated Debt in respect of cash, property or securities
of the Company, as the case may be, received upon the exercise of any such
remedy.

         Upon any payment or distribution of assets of the Company referred to
in this Article XVI, the Trustee, subject to the provisions of Section 9.01,
and the Holders of the Junior Subordinated Debentures shall be entitled to
conclusively rely upon any order or decree made by any court of competent
jurisdiction in which such dissolution, winding-up, liquidation or
reorganization proceedings are pending, or a certificate of the receiver,
trustee in bankruptcy, liquidation trustee, agent or other Person making such
payment or distribution, delivered to the Trustee or to the Holders of the
Junior Subordinated Debentures, for the purposes of ascertaining the Persons
entitled to participate in such distribution, the holders of Senior and
Subordinated Debt and other indebtedness of the Company, as the case may be,
the amount thereof or payable thereon, the amount or amounts paid or
distributed thereon and all other facts pertinent thereto or to this Article
XVI.

         16.05 TRUSTEE TO EFFECTUATE SUBORDINATION. Each Holder of Junior
Subordinated Debentures by such Holder's acceptance thereof authorizes and
directs the Trustee on such Holder's behalf to take such action as may be
necessary or appropriate to effectuate the subordination provided in this
Article XVI and appoints the Trustee such Holder's attorney-in-fact for any and
all such purposes.

         16.06 NOTICE BY THE COMPANY. The Company shall give prompt written
notice to a Responsible Officer of the Trustee of any fact known to the Company
that would prohibit the making of any payment of moneys to or by the Trustee in
respect of the Junior Subordinated Debentures pursuant to the provisions of
this Article XVI. Notwithstanding the provisions of this Article XVI or any
other provision of this Indenture, the Trustee shall not be charged with
knowledge of the existence of any facts that would prohibit the making of any
payment of moneys to or by the Trustee in respect of the Junior Subordinated
Debentures pursuant to the provisions of this Article XVI, unless and until a
Responsible Officer of the Trustee shall have received written notice thereof
from the Company or a holder or holders of Senior and Subordinated Debt or from
any trustee therefor; and before the receipt of any such written notice, the
Trustee, subject to the provisions of Section 9.01, shall be entitled in all
respects to assume that no such facts exist; provided, however, that if the
Trustee shall not have received the notice provided for in this Section


                                       52
<PAGE>   59
         16.06 at least two Business Days prior to the date upon which by the
terms hereof any money may become payable for any purpose (including, without
limitation, the payment of the principal of or interest on any Junior
Subordinated Debenture), then, anything herein contained to the contrary
notwithstanding, the Trustee shall have full power and authority to receive such
money and to apply the same to the purposes for which it was received, and shall
not be affected by any notice to the contrary that may be received by it within
two Business Days prior to such date.

         The Trustee, subject to the provisions of Section 9.01, shall be
entitled to conclusively rely on the delivery to it of a written notice by a
Person representing himself to be a holder of Senior and Subordinated Debt of
the Company (or a trustee on behalf of such holder), to establish that such
notice has been given by a holder of such Senior and Subordinated Debt or a
trustee on behalf of any such holder or holders. In the event that the Trustee
determines in good faith that further evidence is required with respect to the
right of any Person as a holder of such Senior and Subordinated Debt to
participate in any payment or distribution pursuant to this Article XVI, the
Trustee may request such Person to furnish evidence to the reasonable
satisfaction of the Trustee as to the amount of such Senior and Subordinated
Debt held by such Person, the extent to which such Person is entitled to
participate in such payment or distribution and any other facts pertinent to
the rights of such Person under this Article XVI, and, if such evidence is not
furnished, the Trustee may defer any payment to such Person pending judicial
determination as to the right of such Person to receive such payment.

         16.07 RIGHTS OF THE TRUSTEE; HOLDERS OF SENIOR AND SUBORDINATED DEBT.
The Trustee in its individual capacity shall be entitled to all the rights set
forth in this Article XVI in respect of any Senior and Subordinated Debt at any
time held by it, to the same extent as any other holder of Senior and
Subordinated Debt, and nothing in this Indenture shall deprive the Trustee of
any of its rights as such holder.

         With respect to the holders of Senior and Subordinated Debt of the
Company, the Trustee undertakes to perform or to observe only such of its
covenants and obligations as are specifically set forth in this Article XVI,
and no implied covenants or obligations with respect to the holders of such
Senior and Subordinated Debt shall be read into this Indenture against the
Trustee. The Trustee shall not be deemed to owe any fiduciary duty to the
holders of such Senior and Subordinated Debt and, subject to the provisions of
Section 9.01, the Trustee shall not be liable to any holder of such Senior and
Subordinated Debt if it shall pay over or deliver to Holders of Junior
Subordinated Debentures, the Company or any other Person money or assets to
which any holder of such Senior and Subordinated Debt shall be entitled by
virtue of this Article XVI or otherwise.

         16.08 SUBORDINATION MAY NOT BE IMPAIRED. No right of any present or
future holder of any Senior and Subordinated Debt of the Company to enforce
subordination as herein provided shall at any time in any way be prejudiced or
impaired by any act or failure to act on the part of the Company or by any act
or failure to act, in good faith, by any such holder, or by any noncompliance
by the Company with the terms, provisions and covenants of this Indenture,
regardless of any knowledge thereof that any such holder may have or otherwise
be charged with.


                                       53
<PAGE>   60

         Without in any way limiting the generality of the foregoing paragraph,
the holders of Senior and Subordinated Debt of the Company may, at any time and
from time to time, without the consent of or notice to the Trustee or the
Holders of the Junior Subordinated Debentures, without incurring responsibility
to the Holders of the Junior Subordinated Debentures and without impairing or
releasing the subordination provided in this Article XVI or the obligations
hereunder of the Holders of the Junior Subordinated Debentures to the holders
of such Senior and Subordinated Debt, do any one or more of the following: (a)
change the manner, place or terms of payment or extend the time of payment of,
or renew or alter, such Senior and Subordinated Debt, or otherwise amend or
supplement in any manner such Senior and Subordinated Debt or any instrument
evidencing the same or any agreement under which such Senior and Subordinated
Debt is outstanding; (b) sell, exchange, release or otherwise deal with any
property pledged, mortgaged or otherwise securing such Senior and Subordinated
Debt; (c) release any Person liable in any manner for the collection of such
Senior and Subordinated Debt; and (d) exercise or refrain from exercising any
rights against the Company and any other Person.

         IN WITNESS WHEREOF, the parties hereto have caused this Indenture to
be duly executed as of the day and year first above written.

                                      ENTERBANK HOLDINGS, INC.


                                      By:
                                         ---------------------------------
                                         Chief Executive Officer

Attest:


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

                                      WILMINGTON TRUST COMPANY, as Trustee


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

Attest:


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


                                       54
<PAGE>   61

                                   EXHIBIT A

                (FORM OF FACE OF JUNIOR SUBORDINATED DEBENTURE)


                                                    Registered Principal Amount

Registered No. _______________                      $__________

[CUSIP NO. _______________]

                            ENTERBANK HOLDINGS, INC.
                      ____% JUNIOR SUBORDINATED DEBENTURE
                           DUE ________________, 2029

         ENTERBANK HOLDINGS, INC., a Delaware corporation (the "Company," which
term includes any successor corporation under the Indenture hereinafter
referred to), for value received, hereby promises to pay to WILMINGTON TRUST
COMPANY as Property Trustee of EBH Capital Trust I or registered assigns, the
principal sum of _______________________________________ Dollars ($__________)
on ________________, 2029 (which date may be shortened as provided in the
Indenture, the "Stated Maturity"), and to pay interest on said principal sum
from ________________, 1999, or from the most recent interest payment date
(each such date, an "Interest Payment Date") to which interest has been paid or
duly provided for, quarterly (subject to deferral as set forth herein) in
arrears on the 15th day of March, June, September and December in each year
commencing December 15, 1999, at the rate of ____% per annum until the
principal hereof shall have become due and payable, and on any overdue
principal and (without duplication and to the extent that payment of such
interest is enforceable under applicable law) on any overdue installment of
interest at the same rate per annum compounded quarterly. The amount of each
interest payment due with respect to the Junior Subordinated Debentures will
include amounts accrued through the date the interest payment is due. The
amount of interest payable on any Interest Payment Date shall be computed on
the basis of a 360-day year of twelve 30-day months. In the event that any date
on which interest is payable on this Junior Subordinated Debenture is not a
Business Day (as defined in the Indenture), then payment of interest payable on
such date will be made on the next succeeding day that is a Business Day (and
without any interest or other payment in respect of any such delay), except
that, if such Business Day is in the next succeeding calendar year, such
payment shall be made on the immediately preceding Business Day, in each case
with the same force and effect as if made on such date. The interest
installment so payable, and punctually paid or duly provided for, on any
Interest Payment Date will, as provided in the Indenture, be paid to the person
in whose name this Junior Subordinated Debenture (or one or more Predecessor
Junior Subordinated Debentures, as defined in the Indenture) is registered at
the close of business on the regular record date for such interest installment,
which shall be the close of business on the business day next preceding such
Interest Payment Date unless otherwise provided in the Indenture. The principal
of and the interest on this Junior Subordinated Debenture shall be payable at
the office or


                                      A-1
<PAGE>   62

agency of the Trustee (as defined in the Indenture) maintained for that purpose
in any coin or currency of the United States of America that at the time of
payment is legal tender for payment of public and private debts; provided,
however, that payment of interest may be made at the option of the Company by
check mailed to the Registered Holder (as defined in the Indenture) at such
address as shall appear in the Securities Register (as defined in the
Indenture). Notwithstanding the foregoing, so long as the Holder of this Junior
Subordinated Debenture is the Property Trustee (as defined in the Indenture),
the payment of the principal of and interest on this Junior Subordinated
Debenture will be made at such place and to such account as may be designated
by the Property Trustee.

         The Stated Maturity may be shortened at any time by the Company to any
date not earlier than ________________, 2004, subject to the Company having
received prior approval of the Federal Reserve (as defined in the Indenture) if
then required under applicable capital guidelines or policies of the Federal
Reserve.

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

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

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


                                      A-2
<PAGE>   63

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

Dated:                                ENTERBANK HOLDINGS, INC.
       ------------------

                                      By:
                                          ------------------------------------
                                          Chief Executive Officer

Attest:

By:
    -------------------------------
    Secretary


                                      A-3
<PAGE>   64

                    [FORM OF CERTIFICATE OF AUTHENTICATION]

                         CERTIFICATE OF AUTHENTICATION


         This is one of the Junior Subordinated Debentures described in the
within-mentioned Indenture.

Dated:                                 WILMINGTON TRUST COMPANY, as Trustee
      ---------------------

                                       By:
                                           ------------------------------
                                           Authorized Signature


                                      A-4
<PAGE>   65

               [FORM OF REVERSE OF JUNIOR SUBORDINATED DEBENTURE]
                      ____% JUNIOR SUBORDINATED DEBENTURE
                                  (CONTINUED)

         This Junior Subordinated Debenture is one of the junior subordinated
debentures of the Company (herein sometimes referred to as the "Junior
Subordinated Debentures"), specified in the Indenture, all issued under and
pursuant to a Subordinated Indenture dated as of ________________, 1999 (the
"Indenture") duly executed and delivered between the Company and WILMINGTON
TRUST COMPANY, as Trustee (the "Trustee"), to which Indenture reference is
hereby made for a description of the rights, limitations of rights,
obligations, duties and immunities thereunder of the Trustee, the Company and
the Holders of the Junior Subordinated Debentures. The Junior Subordinated
Debentures are limited in aggregate principal amount as specified in the
Indenture.

         Because of the occurrence and continuation of a Special Event (as
defined in the Indenture), in certain circumstances, this Junior Subordinated
Debenture may become due and payable at the option of the Company at the
principal amount together with any interest accrued thereon (the "Redemption
Price"). The Redemption Price shall be paid prior to 2:00 p.m. St. Louis,
Missouri time, on the date of such redemption or at such earlier time as the
Company determines.

         The Company shall have the right to redeem this Junior Subordinated
Debenture at the option of the Company, in whole or in part, from time to time,
on or after ________________, 2004, at a redemption price equal to 100% of the
principal amount to be redeemed plus any accrued but unpaid interest thereon to
the date of such redemption. Any redemption pursuant to this paragraph will be
made upon not less than 30 days' nor more than 60 days' notice. If the Junior
Subordinated Debentures are only partially redeemed by the Company pursuant to
this paragraph, the Junior Subordinated Debentures will be redeemed pro rata or
by lot or by any other method utilized by the Trustee; provided that if, at the
time of redemption, the Junior Subordinated Debentures are registered as a
Global Subordinated Debenture (as defined in the Indenture), the Depositary (as
defined in the Indenture) shall determine the principal amount of such Junior
Subordinated Debentures held by each Junior Subordinated Debenture Holder to be
redeemed in accordance with its procedures.

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

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

         The Indenture contains provisions permitting the Company and the
Trustee, with the consent of the Holders of not less than a majority in
aggregate principal amount of the Junior Subordinated


                                      A-5
<PAGE>   66

Debentures at the time Outstanding, as defined in the Indenture, to execute
supplemental indentures for the purpose of adding any provisions to or changing
in any manner or eliminating any of the provisions of the Indenture or of any
supplemental indenture or of modifying in any manner the rights of the Holders
of the Junior Subordinated Debentures; provided, however, that no such
supplemental indenture shall (i) change the stated maturity of the Junior
Subordinated Debentures except as provided in the Indenture, or reduce the
principal amount thereof, or reduce the rate or extend the time of payment of
interest thereon, without the consent of the Holder of each Junior Subordinated
Debenture so affected, or (ii) reduce the aforesaid percentage of Junior
Subordinated Debentures, the Holders of which are required to consent to any
such supplemental indenture, without the consent of the Holders of each Junior
Subordinated Debenture then Outstanding and affected thereby. The Indenture
also contains provisions permitting the Holders of a majority in aggregate
principal amount of the Junior Subordinated Debentures at the time Outstanding,
on behalf of all of the Holders of the Junior Subordinated Debentures, to waive
any past default in the performance of any of the covenants contained in the
Indenture, or established pursuant to the Indenture, and its consequences,
except a default in the payment of the principal of or interest on any of the
Junior Subordinated Debentures. Any such consent or waiver by the registered
Holder of this Junior Subordinated Debenture (unless revoked as provided in the
Indenture) shall be conclusive and binding upon such Holder and upon all future
Holders and owners of this Junior Subordinated Debenture and of any Junior
Subordinated Debenture issued in exchange herefor or in place hereof (whether
by registration of transfer or otherwise), irrespective of whether or not any
notation of such consent or waiver is made upon this Junior Subordinated
Debenture.

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

         The Company shall have the right at any time during the term of the
Junior Subordinated Debentures and from time to time to extend the interest
payment period of such Junior Subordinated Debentures for up to 20 consecutive
quarters (an "Extended Interest Payment Period"), at the end of which period
the Company shall pay all interest then accrued and unpaid (together with
interest thereon at the rate specified for the Junior Subordinated Debentures
to the extent that payment of such interest is enforceable under applicable
law). Before the termination of any such Extended Interest Payment Period, the
Company may further extend such Extended Interest Payment Period, provided that
such Extended Interest Payment Period together with all such further extensions
thereof shall not exceed 20 consecutive quarters or extend beyond the Stated
Maturity. At the termination of any such Extended Interest Payment Period and
upon the payment of all accrued and unpaid interest and any additional amounts
then due, the Company may commence a new Extended Interest Payment Period.

         The Company has agreed that if at any time (a) there shall have
occurred any event of which the Company has actual knowledge that (i) with the
giving of notice or the lapse of time, or both, would constitute an Event of
Default and (ii) in respect to which the Company shall not have taken


                                      A-6
<PAGE>   67

reasonable steps to cure, or (b) the Company shall have given notice of its
election of an Extended Interest Payment Period as provided herein and shall
not have rescinded such notice, or such Extended Interest Payment Period, or
any extension thereof, shall be continuing; or (c) while the Junior
Subordinated Debentures are held by the Trust, the Company shall be in default
with respect to its payment of any obligation under the Preferred Securities
Guarantee, then the Company will not (i) declare or pay any dividends or
distributions on, or redeem, purchase, acquire, or make a liquidation payment
with respect to, any of the Company's capital stock or (ii) make any payment of
principal, interest or premium, if any, on or repay, repurchase or redeem any
debt securities of the Company (including the Junior Subordinated Debentures)
that rank pari passu with or junior in interest to the Junior Subordinated
Debentures or make any guarantee payments with respect to any guarantee by the
Company of the debt securities of any subsidiary of the Company if such
guarantee ranks pari passu or junior in interest to the Junior Subordinated
Debentures (other than (A) dividends or distributions in common stock, (B) any
declaration of a dividend in connection with the implementation of a
shareholders' rights plan, or the issuance of stock under any such plan in the
future or the redemption or repurchase of any such rights pursuant thereto, (C)
payments under the Preferred Securities Guarantee and (D) purchases of common
stock related to the issuance of common stock or rights under any of the
Company's benefit plans for its directors, officers or employees).

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

         Prior to due presentment for registration of transfer of this Junior
Subordinated Debenture, the Company, the Trustee, any paying agent and the
Securities Registrar (as defined in the Indenture) may deem and treat the
Registered Holder hereof as the absolute owner hereof (whether or not this
Junior Subordinated Debenture shall be overdue and notwithstanding any notice
of ownership or writing hereon made by anyone other than the Securities
Registrar) for the purpose of receiving payment of or on account of the
principal hereof and interest due hereon and for all other purposes, and
neither the Company nor the Trustee nor any paying agent nor any Securities
Registrar shall be affected by any notice to the contrary.

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


                                      A-7
<PAGE>   68
of any constitution, statute or rule of law, or by the enforcement of any
assessment or penalty or otherwise, all such liability being, by the acceptance
hereof and as part of the consideration for the issuance hereof, expressly
waived and released.

         The Junior Subordinated Debentures are issuable only in registered
form without coupons in denominations of $10 and any integral multiple thereof.

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


                                      A-8