Document:

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                                                                     Exhibit 4.9

                    PREFERRED SECURITIES GUARANTEE AGREEMENT

                           Colonial Capital Trust III

                          Dated as of _______ __, 2002

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                                Table of Contents

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                                    ARTICLE I

                         DEFINITIONS AND INTERPRETATION

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

                                   ARTICLE II

                               TRUST INDENTURE ACT

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

                                   ARTICLE III

                     POWERS, DUTIES AND RIGHTS OF PREFERRED
                                GUARANTEE TRUSTEE

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

                                   ARTICLE IV

                           PREFERRED GUARANTEE TRUSTEE

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

                                    ARTICLE V

                                    GUARANTEE

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

                                   ARTICLE VI

                    LIMITATION OF TRANSACTIONS; SUBORDINATION

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

                                   ARTICLE VII

                                   TERMINATION

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

                                  ARTICLE VIII

                                 INDEMNIFICATION

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

                                   ARTICLE IX

                                  MISCELLANEOUS

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

     This GUARANTEE AGREEMENT (the "Preferred Securities Guarantee"), dated as
of _______ __, 2002, is executed and delivered by The Colonial BancGroup, Inc.,
a Delaware corporation (the "Guarantor"), and The Bank of New York, a New York
banking corporation, as trustee (the "Preferred Guarantee Trustee"), for the
benefit of the Holders (as defined herein) of Colonial Capital Trust III, a
Delaware statutory business trust (the "Issuer").

     WHEREAS, pursuant to an Amended and Restated Declaration of Trust (the
"Declaration"), dated as of _______ __, 2002, among the trustees of the Issuer
named therein, the Guarantor, as sponsor, and the holders from time to time of
undivided beneficial interests in the assets of the Issuer, the Issuer is
issuing on the Closing Date _______ preferred securities, having an aggregate
liquidation amount of $_______ designated as the __% Preferred Securities (the
"Preferred Securities") (and may issue up to $_______ in aggregate liquidation
amount of additional Preferred Securities pursuant to an over-allotment option
granted to the underwriters of the Preferred Securities); and

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

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

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

                                   ARTICLE I

                         DEFINITIONS AND INTERPRETATION

     SECTION 1.1 Definitions and Interpretation

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

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

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

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

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

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

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

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

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

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

     "Business Day" means any day other than Saturday, Sunday or any other day
on which commercial banking institutions in The City of New York are permitted
or required by applicable law, regulation or executive order to close.

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

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

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

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

     "Debentures" means the __% Junior Subordinated Debentures due 2032 issued
by the Guarantor to the Issuer.

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

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

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

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

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

     "Indenture" means the Indenture dated as of _______ __, 2002, between the
Guarantor (the "Debenture Issuer") and The Bank of New York, as trustee, and any
indenture supplemental thereto pursuant to which certain subordinated debt
securities of the Debenture Issuer are to be issued to the Institutional Trustee
of the Issuer.

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

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

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

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

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

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

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

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

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

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

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

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

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

                                   ARTICLE II

                               TRUST INDENTURE ACT

     SECTION 2.1 Trust Indenture Act; Application

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

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

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

     SECTION 2.2 Lists of Holders of Securities

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

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

     SECTION 2.3 Reports by the Preferred Guarantee Trustee

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

     (b) A copy of each such report shall, at the time of such transmission to
Holders, be filed by the Institutional Trustee with each stock exchange, if any,
upon which the Securities are listed, with the Commission and with the Trust.
The Trust will promptly notify the Institutional Trustee when the Securities are
listed on any stock exchange and of any delisting thereof.

     SECTION 2.4 Periodic Reports to Preferred Guarantee Trustee

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

     SECTION 2.5 Evidence of Compliance with Conditions Precedent

     The Guarantor shall provide to the Preferred Guarantee Trustee such
evidence of compliance with any conditions precedent, if any, provided for in
this Preferred Securities Guarantee that relate to any of the matters set forth
in Section 314(c) of the Trust Indenture Act.

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Any certificate or opinion required to be given by an officer pursuant to
Section 314(c)(1) may be given in the form of an Officers' Certificate.

     SECTION 2.6 Events of Default; Waiver

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

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

     SECTION 2.7 Event of Default; Notice

     (a) The Preferred Guarantee Trustee shall, within 60 days after the
occurrence of an Event of Default, transmit by mail, first class postage
prepaid, to the Holders, notices of all Events of Default actually known to a
Responsible Officer of the Preferred Guarantee Trustee, unless such defaults
have been cured before the giving of such notice, provided, that, the Preferred
Guarantee Trustee shall be protected in withholding such notice if and so long
as a Responsible Officer in good faith determines that the withholding of such
notice is in the interests of the Holders of the Preferred Securities.

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

     SECTION 2.8 Conflicting Interests

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

                                  ARTICLE III

                     POWERS, DUTIES AND RIGHTS OF PREFERRED
                                GUARANTEE TRUSTEE

     SECTION 3.1 Powers and Duties of the Preferred Guarantee Trustee

     (a) This Preferred Securities Guarantee shall be held by the Preferred
Guarantee Trustee in trust for the benefit of the Holders, and the Preferred
Guarantee Trustee shall not transfer its right, title and interest in this
Preferred Securities Guarantee to any Person except a

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Holder exercising his or her rights pursuant to Section 5.4(d) or to a Successor
Preferred Guarantee Trustee on acceptance by such Successor Preferred Guarantee
Trustee of its appointment to act as Successor Preferred Guarantee Trustee. The
right, title and interest of the Preferred Guarantee Trustee shall automatically
vest in any Successor Preferred Guarantee Trustee, and such vesting and
cessation of title shall be effective whether or not conveyancing documents have
been executed and delivered pursuant to the appointment of such Successor
Preferred Guarantee Trustee.

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

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

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

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

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

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

              (B) in the absence of bad faith on the part of the Preferred
         Guarantee Trustee, the Preferred Guarantee Trustee may conclusively
         rely, as to the truth of the statements and the correctness of the
         opinions expressed therein, upon any certificates or opinions furnished
         to the Preferred Guarantee Trustee and

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         conforming to the requirements of this Preferred Securities Guarantee;
         but in the case of any such certificates or opinions that by any
         provision hereof are specifically required to be furnished to the
         Preferred Guarantee Trustee, the Preferred Guarantee Trustee shall be
         under a duty to examine the same to determine whether or not they
         conform to the requirements of this Preferred Securities Guarantee;

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

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

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

     SECTION 3.2 Certain Rights of Preferred Guarantee Trustee

     (a) Subject to the provisions of Section 3.1:

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

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

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

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

           (v)    The Preferred Guarantee Trustee may consult with counsel of
     its selection, and the advice or opinion of such counsel with respect to
     legal matters shall be full and complete authorization and protection in
     respect of any action taken, suffered or omitted by it hereunder in good
     faith and in accordance with such advice or opinion. Such counsel may be
     counsel to the Guarantor or any of its Affiliates and may include any of
     its employees. The Preferred Guarantee Trustee shall have the right at any
     time to seek instructions concerning the administration of this Preferred
     Securities Guarantee from any court of competent jurisdiction.

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

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

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

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

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

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

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

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

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

                                   ARTICLE IV

                           PREFERRED GUARANTEE TRUSTEE

     SECTION 4.1  Preferred Guarantee Trustee; Eligibility

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

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

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

                                       10

<PAGE>

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

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

     SECTION 4.2 Appointment, Removal and Resignation of Preferred Guarantee
Trustee

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

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

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

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

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

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

                                       11

<PAGE>

                                   ARTICLE V

                                    GUARANTEE

     SECTION 5.1 Guarantee

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

     SECTION 5.2 Waiver of Notice and Demand

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

     SECTION 5.3 Obligations Not Affected

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

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

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

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

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

                                       12

<PAGE>

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

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

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

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

     SECTION 5.4 Enforcement of Guarantee; Rights of Holders

     The Guarantor and the Preferred Guarantee Trustee expressly acknowledge
that:

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

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

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

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

     SECTION 5.5 Guarantee of Payment

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

     SECTION 5.6 Subrogation

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

                                       13

<PAGE>

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

     SECTION 5.7 Independent Obligations

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

                                   ARTICLE VI

                    LIMITATION OF TRANSACTIONS; SUBORDINATION

     SECTION 6.1 Limitation of Transactions

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

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

                                       14

<PAGE>

     SECTION 6.2 Ranking

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

                                   ARTICLE VII

                                   TERMINATION

     SECTION 7.1 Termination

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

                                  ARTICLE VIII

                                 INDEMNIFICATION

     SECTION 8.1 Exculpation

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

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

                                       15

<PAGE>

     SECTION 8.2 Indemnification

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

                                   ARTICLE IX

                                  MISCELLANEOUS

     SECTION 9.1 Successors and Assigns

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

     SECTION 9.2 Amendments

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

     SECTION 9.3 Notices

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

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

                                       16

<PAGE>

                         The Bank of New York
                         c/o The Bank of New York Trust Company of Florida, N.A.
                         10161 Centurion Parkway
                         Jacksonville, Florida 32256
                         Attention:  Corporate Trust Administration

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

                         The Colonial BancGroup, Inc.
                         One Commerce Street
                         P.O. Box 1108
                         Montgomery, Alabama  36101-1108
                         Attention:  William A. McCrary, Senior Counsel

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

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

     SECTION 9.4 Benefit

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

     SECTION 9.5 Governing Law

     This Preferred Securities Guarantee shall be governed by, and construed in
accordance with, the laws of the State of New York, without regard to conflicts
of laws principles thereof.

     SECTION 9.6 Genders

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

     SECTION 9.7 Counterparts

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

                                       17

<PAGE>

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

THE COLONIAL BANCGROUP, INC.,
as Guarantor

By:  _____________________________________
     Name:  W. Flake Oakley
     Title:  Chief Financial Officer

THE BANK OF NEW YORK,
as Preferred Guarantee Trustee

By:  _____________________________________
     Name:
     Title:

                                       18<PAGE>
                                                                    Exhibit 4.10

                      COMMON SECURITIES GUARANTEE AGREEMENT

                           Colonial Capital Trust III

                           Dated as of _____ __, 2002

<PAGE>

                                Table of Contents
<TABLE>
<CAPTION>
                                                                          Page
                                                                          ----
<S>                                                                       <C>
                                    ARTICLE I
                         DEFINITIONS AND INTERPRETATION

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

                                   ARTICLE II
                                    GUARANTEE

SECTION 2.1       Guarantee ..............................................  4
SECTION 2.2       Subordination ..........................................  4
SECTION 2.3       Waiver of Notice and Demand ............................  4
SECTION 2.4       Obligations Not Affected ...............................  4
SECTION 2.5       Rights of Holders ......................................  5
SECTION 2.6       Guarantee of Payment ...................................  5
SECTION 2.7       Subrogation ............................................  5
SECTION 2.8       Independent Obligations ................................  6

                                   ARTICLE III
                    LIMITATION OF TRANSACTIONS; SUBORDINATION

SECTION 3.1       Limitation of Transactions .............................  6
SECTION 3.2       Ranking ................................................  6

                                   ARTICLE IV
                                   TERMINATION

SECTION 4.1       Termination ............................................  7

                                    ARTICLE V
                                  MISCELLANEOUS

SECTION 5.1       Successors and Assigns .................................  7
SECTION 5.2       Amendments .............................................  7
SECTION 5.3       Notices ................................................  7
SECTION 5.4       Benefit ................................................  8
SECTION 5.5       Governing Law ..........................................  8
SECTION 5.6       Genders ................................................  8
</TABLE>

                                        i

<PAGE>

                      COMMON SECURITIES GUARANTEE AGREEMENT

         This GUARANTEE AGREEMENT (the "Common Securities Guarantee"), dated as
of ______ __, 2002, is executed and delivered by The Colonial BancGroup, Inc., a
Delaware corporation (the "Guarantor"), for the benefit of the Holders (as
defined herein) of Colonial Capital Trust III, a Delaware statutory business
trust (the "Issuer").

         WHEREAS, pursuant to an Amended and Restated Declaration of Trust (the
"Declaration"), dated as of ______ __, 2002, among the trustees of the Issuer
named therein, the Guarantor, as sponsor, and the holders from time to time of
undivided beneficial interests in the assets of the Issuer, the Issuer is
issuing on the Closing Date _____ common securities, having an aggregate
liquidation amount of $____ designated as the __% Common Securities (the "Common
Securities") (and may issue up to $______________ in aggregate liquidation
amount of additional Common Securities pursuant to an over-allotment option
granted to the underwriters of the Preferred Securities (as defined herein) of
the Trust);

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

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

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

                                   ARTICLE I

                         DEFINITIONS AND INTERPRETATION

         SECTION 1.1       Definitions and Interpretation

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

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

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

<PAGE>

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

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

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

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

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

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

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

         "Business Day" means any day other than Saturday, Sunday or any other
day on which commercial banking institutions in The City of New York are
permitted or required by applicable law, regulation or executive order to close.

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

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

         "Debentures" means the __% Junior Subordinated Debentures due 2032
issued by the Guarantor to the Issuer.

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

         "Guarantee Payments" means the following payments or distributions,
without duplication, with respect to the Common Securities, to the extent not
paid or made by the Issuer: (i) any accrued and unpaid Distributions (as defined
in the Declaration) that are required to be paid on such Common Securities, to
the extent the Issuer shall have funds available therefor, (ii) the redemption
price, including all accrued and unpaid Distributions to the date of redemption
(the "Redemption Price"), to the extent the Issuer has funds available therefor,
with respect to any Common Securities called for redemption by the Issuer, and
(iii) upon dissolution of the Issuer (other than in connection with the
distribution of Debentures to the Holders or the redemption of all of the Common
Securities as provided in the Declaration), the lesser of (a) the aggregate of
the liquidation amount and all accrued and unpaid Distributions on the Common

                                       2

<PAGE>

Securities to the date of payment, to the extent the Issuer shall have funds
available therefor, and (b) the amount of assets of the Issuer remaining
available for distribution to Holders in liquidation of the Issuer (in either
case, the "Liquidation Distribution"). If an event of default under the
Indenture has occurred and is continuing, the rights of holders of the Preferred
Securities to receive payments under the Preferred Securities Guarantee
Agreement rank senior and prior in right to the rights of Holders to receive
Guarantee Payments (as defined in the Preferred Securities Guarantee).

         "Holder" means any holder, as registered on the books and records of
the Issuer, of any Common Securities.

         "Indenture" means the Indenture dated as of _____ __, 2002, as
supplemented by the First Supplemental Indenture, dated _____ __, 2002 (the
"First Supplemental Indenture"), each between the Guarantor (the "Debenture
Issuer") and The Bank of New York, as trustee, and any indenture supplemental
thereto pursuant to which certain subordinated debt securities of the Debenture
Issuer are to be issued to the Institutional Trustee of the Issuer.

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

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

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

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

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

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

         "Preferred Securities" means the preferred securities of the Issuer
having an aggregate liquidation amount of up to $_______, designated as the __%
Preferred Securities.

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

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

                                       3

<PAGE>

                                   ARTICLE II

                                    GUARANTEE

         SECTION 2.1    Guarantee

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

         SECTION 2.2    Subordination

         If (a) an Event of Default or (b) an event of default under the
Indenture has occurred and is continuing, the rights of Holders to receive
Guarantee Payments under this Common Securities Guarantee are subordinated to
the rights of holders of Preferred Securities to receive Guarantee Payments (as
defined in the Preferred Securities Guarantee) under the Preferred Securities
Guarantee.

         SECTION 2.3    Waiver of Notice and Demand

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

         SECTION 2.4    Obligations Not Affected

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

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

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

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

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

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

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

        (g) any other circumstance whatsoever that might otherwise constitute a
legal or equitable discharge or defense of a guarantor, it being the intent of
this Section 2.4 that the obligations of the Guarantor hereunder shall be
absolute and unconditional under any and all circumstances.

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

        SECTION 2.5     Rights of Holders

        The Guarantor expressly acknowledges that any Holder may institute a
legal proceeding directly against the Guarantor to enforce its rights under this
Common Securities Guarantee without first instituting a legal proceeding against
the Issuer or any other Person.

        SECTION 2.6     Guarantee of Payment

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

        SECTION 2.7     Subrogation

        The Guarantor shall be subrogated to all (if any) rights of the Holders
against the Issuer in respect of any amounts paid to such Holders by the
Guarantor under this Common Securities Guarantee; provided, however, that the
Guarantor shall not (except to the extent required by mandatory provisions of
law) be entitled to enforce or exercise any right that it may acquire by way of
subrogation or any indemnity, reimbursement or other agreement, in all cases as
a result of payment under this Common Securities Guarantee, if, at the time of
any such payment, any amounts are due and unpaid under this Common Securities
Guarantee. If any amount shall be paid to the Guarantor in violation of the
preceding sentence, the Guarantor agrees to hold such amount in trust for the
Holders and to pay over such amount to the Holders.

                                       5

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         SECTION 2.8    Independent Obligations

         The Guarantor acknowledges that its obligations hereunder are
independent of the obligations of the Issuer with respect to the Common
Securities, and that the Guarantor shall be liable as principal and as debtor
hereunder to make Guarantee Payments pursuant to the terms of this Common
Securities Guarantee notwithstanding the occurrence of any event referred to in
subsections (a) through (g), inclusive, of Section 2.4 hereof.

                                  ARTICLE III

                    LIMITATION OF TRANSACTIONS; SUBORDINATION

         SECTION 3.1    Limitation of Transactions

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

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

         SECTION 3.2    Ranking

         This Common Securities Guarantee will constitute an unsecured
obligation of the Guarantor and will rank (i) subordinate and junior in right of
payment to all other liabilities of the Guarantor, except those made pari passu
or subordinate by their terms, (ii) pari passu with the most senior preferred or
preference stock now or hereafter issued by the Guarantor and with

                                       6

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any guarantee now or hereafter entered into by the Guarantor in respect of any
preferred or preference stock of any Affiliate of the Guarantor, and (iii)
senior to the Guarantor's Common Stock; provided that, in accordance with
Section 2.2, this Common Securities Guarantee will rank subordinate and junior
in right of payment to the Preferred Securities Guarantee.

                                   ARTICLE IV

                                  TERMINATION

         SECTION 4.1     Termination

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

                                   ARTICLE V

                                 MISCELLANEOUS

         SECTION 5.1     Successors and Assigns

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

         SECTION 5.2     Amendments

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

         SECTION 5.3     Notices

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

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<PAGE>

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

The Colonial BancGroup, Inc.
One Commerce Street
P.O. Box 1108
Montgomery, Alabama  36101-1108
Attention:  William A. McCrary, Senior Counsel

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

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

         SECTION 5.4       Benefit

         This Common Securities Guarantee is solely for the benefit of the
Holders and is not separately transferable from the Common Securities.

         SECTION 5.5       Governing Law

         This Common Securities Guarantee shall be governed by, and construed in
accordance with, the laws of the State of New York, without regard to conflicts
of laws principles thereof.

         SECTION 5.6       Genders

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

                                       8

<PAGE>

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

                                    THE COLONIAL BANCGROUP, INC., as
                                    Guarantor

                                    By:_________________________________________
                                    Name: W. Flake Oakley
                                    Title: Chief Financial Officer

                                       9

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