<PAGE>   1
                                                                     EXHIBIT 4.2

                          REGIONS FINANCIAL CORPORATION

                                       TO

                             BANKERS TRUST COMPANY,
                                   as Trustee

                                    INDENTURE

                          Dated as of ___________, 2001

                          SUBORDINATED DEBT SECURITIES




<PAGE>   2
                                TABLE OF CONTENTS

<TABLE>
<S>                                                                                                     <C>
ARTICLE ONE - DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION....................................1
   SECTION 101.  Definitions.............................................................................1
   SECTION 102.  Compliance Certificates and Opinions...................................................10
   SECTION 103.  Form of Documents Delivered to Trustee.................................................11
   SECTION 104.  Acts of Holders........................................................................11
   SECTION 105.  Notices, etc., the Trustee and Company.................................................13
   SECTION 106.  Notice to Holders; Waiver..............................................................13
   SECTION 107.  Effect of Headings and Table of Contents...............................................14
   SECTION 108.  Successors and Assigns.................................................................14
   SECTION 109.  Separability Clause....................................................................14
   SECTION 110.  Benefits of Indenture..................................................................14
   SECTION 111.  No Personal Liability..................................................................15
   SECTION 112.  Governing Law..........................................................................15
   SECTION 113.  Legal Holidays.........................................................................15
ARTICLE TWO - SECURITIES FORMS..........................................................................15
   SECTION 201.  Forms of Securities....................................................................15
   SECTION 202.  Form of Trustee's Certificate of Authentication........................................16
   SECTION 203.  Securities Issuable in Global Form.....................................................16
ARTICLE THREE - THE SECURITIES..........................................................................17
   SECTION 301.  Amount Unlimited; Issuable in Series...................................................17
   SECTION 302.  Denominations..........................................................................20
   SECTION 303.  Execution, Authentication, Delivery and Dating.........................................20
   SECTION 304.  Temporary Securities...................................................................22
   SECTION 305.  Registration, Registration of Transfer and Exchange....................................24
   SECTION 306.  Mutilated, Destroyed, Lost and Stolen Securities.......................................26
   SECTION 307.  Payment of Interest; Interest Rights Preserved.........................................27
   SECTION 308.  Persons Deemed Owners..................................................................29
   SECTION 309.  Cancellation...........................................................................29
   SECTION 310.  Computation of Interest................................................................29
   SECTION 311.  Deferrals of Interest Payment Dates....................................................30
   SECTION 312.  Right of Set-Off.......................................................................31
   SECTION 313.  Agreed Tax Treatment...................................................................31
   SECTION 314.  CUSIP Numbers..........................................................................31
   SECTION 315.  Shortening of Stated Maturity..........................................................31
ARTICLE FOUR - SATISFACTION AND DISCHARGE...............................................................31
   SECTION 401.  Satisfaction and Discharge of Indenture................................................31
   SECTION 402.  Application of Trust Funds.............................................................32
ARTICLE FIVE - REMEDIES.................................................................................33
   SECTION 501.  Events of Default......................................................................33
   SECTION 502.  Acceleration of Maturity; Rescission and Annulment.....................................34
   SECTION 503.  Collection of Indebtedness and Suits for Enforcement by Trustee........................35
   SECTION 504.  Trustee May File Proofs of Claim.......................................................36
   SECTION 505.  Trustee May Enforce Claims Without Possession of Securities or Coupons.................36
   SECTION 506.  Application of Money Collected.........................................................37
   SECTION 507.  Limitation on Suits....................................................................37
   SECTION 508.  Unconditional Right of Holders to Receive Principal, Premium or Make-Whole Amount,
   if any, Interest and Additional Amounts; Direct Action by Holders of Preferred Securities............38
   SECTION 509.  Restoration of Rights and Remedies.....................................................38
   SECTION 510.  Rights and Remedies Cumulative.........................................................38
   SECTION 511.  Delay or Omission Not Waiver...........................................................38
   SECTION 512.  Control by Holders of Securities.......................................................38
   SECTION 513.  Waiver of Past Defaults................................................................39
   SECTION 514.  Waiver of Stay, Usury or Extension Laws................................................39
   SECTION 515.  Undertaking for Costs..................................................................39
</TABLE>


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<TABLE>
<S>                                                                                                     <C>
ARTICLE SIX - THE TRUSTEE...............................................................................40
   SECTION 601.  Notice of Defaults.....................................................................40
   SECTION 602.  Certain Duties, Responsibilities and Rights of Trustee.................................40
   SECTION 603.  Not Responsible for Recitals or Issuance of Securities.................................41
   SECTION 604.  May Hold Securities....................................................................41
   SECTION 605.  Money Held in Trust....................................................................41
   SECTION 606.  Compensation and Reimbursement.........................................................42
   SECTION 607.  Corporate Trustee Required; Eligibility................................................42
   SECTION 608.  Resignation and Removal; Appointment of Successor......................................42
   SECTION 609.  Acceptance of Appointment By Successor.................................................43
   SECTION 610.  Merger, Conversion, Consolidation or Succession to Business............................44
   SECTION 611.  Appointment of Authenticating Agent....................................................45
   SECTION 612.  Certain Duties and Responsibilities....................................................46
   SECTION 613.  Conflicting Interests..................................................................46
   SECTION 614.  Preferential Collection of Claims Against Company......................................46
ARTICLE SEVEN - HOLDERS' LISTS AND REPORTS BY TRUSTEE AND COMPANY.......................................46
   SECTION 701.  Disclosure of Names and Addresses of Holders...........................................46
   SECTION 702.  Reports by Trustee.....................................................................46
   SECTION 703.  Reports by Company.....................................................................47
   SECTION 704.  Company to Furnish Trustee Names and Addresses of Holders..............................47
ARTICLE EIGHT - CONSOLIDATION, MERGER, SALE, LEASE OR CONVEYANCE........................................47
   SECTION 801.  Consolidations and Mergers of Company and Sales, Leases and Conveyances Permitted
   Subject to Certain Conditions........................................................................47
   SECTION 802.  Rights and Duties of Successor Corporation.............................................48
   SECTION 803.  Officers' Certificate and Opinion of Counsel...........................................48
ARTICLE NINE - SUPPLEMENTAL INDENTURES..................................................................49
   SECTION 901.  Supplemental Indentures Without Consent of Holders.....................................49
   SECTION 902.  Supplemental Indentures with Consent of Holders........................................50
   SECTION 903.  Execution of Supplemental Indentures...................................................51
   SECTION 904.  Effect of Supplemental Indentures......................................................51
   SECTION 905.  Conformity with Trust Indenture Act....................................................51
   SECTION 906.  Reference in Securities to Supplemental Indentures.....................................51
   SECTION 907.  Notice of Supplemental Indentures......................................................52
   SECTION 908.  Subordination Unimpaired...............................................................52
ARTICLE TEN - COVENANTS.................................................................................52
   SECTION 1001.  Payment of Principal, Premium or Make-Whole Amount, if any, Interest and Additional
   Amounts..............................................................................................52
   SECTION 1002.  Maintenance of Office or Agency.......................................................52
   SECTION 1003.  Money for Securities Payments to Be Held in Trust.....................................53
   SECTION 1004.  Restrictions During Extension Period..................................................54
   SECTION 1005.  Existence.............................................................................55
   SECTION 1006.  Maintenance of Properties.............................................................55
   SECTION 1007.  [Reserved]............................................................................55
   SECTION 1008.  Payment of Taxes and Other Claims.....................................................55
   SECTION 1009.  Provision of Financial Information....................................................55
   SECTION 1010.  Statement as to Compliance............................................................56
   SECTION 1011.  Additional Amounts....................................................................56
   SECTION 1012.  Waiver of Certain Covenants...........................................................57
   SECTION 1013.  Additional Sums.......................................................................57
   SECTION 1014.  Additional Covenants..................................................................57
   SECTION 1015.  Original Issue Discount...............................................................58
ARTICLE ELEVEN - REDEMPTION OF SECURITIES...............................................................58
   SECTION 1101.  Applicability of Article..............................................................58
   SECTION 1102.  Election to Redeem; Notice to Trustee.................................................59
   SECTION 1103.  Selection by Trustee of Securities to Be Redeemed.....................................59
   SECTION 1104.  Notice of Redemption..................................................................59
</TABLE>


                                      -ii-
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<TABLE>
<S>               <C>                                                                                   <C>
   SECTION 1105.  Deposit of Redemption Price...........................................................60
   SECTION 1106.  Securities Payable on Redemption Date.................................................61
   SECTION 1107.  Securities Redeemed in Part...........................................................61
   SECTION 1108.  Right of Redemption of Securities Initially Issued to a Regions Trust.................62
ARTICLE TWELVE - SINKING FUNDS..........................................................................62
   SECTION 1201.  Applicability of Article..............................................................62
   SECTION 1202.  Satisfaction of Sinking Fund Payments with Securities.................................62
   SECTION 1203.  Redemption of Securities for Sinking Fund.............................................62
ARTICLE THIRTEEN - REPAYMENT AT THE OPTION OF HOLDERS...................................................63
   SECTION 1301.  Applicability of Article..............................................................63
   SECTION 1302.  Repayment of Securities...............................................................63
   SECTION 1303.  Exercise of Option....................................................................63
   SECTION 1304.  When Securities Presented for Repayment Become Due and Payable........................64
   SECTION 1305.  Securities Repaid in Part.............................................................64
ARTICLE FOURTEEN - DEFEASANCE AND COVENANT DEFEASANCE...................................................64
   SECTION 1401.  Applicability of Article; Company's Option to Effect Defeasance or Covenant
   Defeasance...........................................................................................64
   SECTION 1402.  Defeasance and Discharge..............................................................65
   SECTION 1403.  Covenant Defeasance...................................................................65
   SECTION 1404.  Conditions to Defeasance or Covenant Defeasance.......................................65
   SECTION 1405.  Deposited Money and Government Obligations to Be Held in Trust; Other Miscellaneous
   Provisions...........................................................................................67
   SECTION 1406.  Reinstatement.........................................................................68
ARTICLE FIFTEEN - MEETINGS OF HOLDERS OF SECURITIES.....................................................68
   SECTION 1501.  Purposes for Which Meetings May Be Called.............................................68
   SECTION 1502.  Call, Notice and Place of Meetings....................................................68
   SECTION 1503.  Persons Entitled to Vote at Meetings..................................................69
   SECTION 1504.  Quorum; Action........................................................................69
   SECTION 1505.  Determination of Voting Rights; Conduct and Adjournment of Meetings...................70
   SECTION 1506.  Counting Votes and Recording Action of Meetings.......................................70
   SECTION 1507.  Evidence of Action Taken by Holders...................................................71
   SECTION 1508.  Proof of Execution of Instruments.....................................................71
ARTICLE SIXTEEN - CONVERSION OR EXCHANGE OF SECURITIES..................................................71
   SECTION 1601.  Applicability of Article..............................................................71
   SECTION 1602.  Election to Exchange; Notice to Trustee and Holders...................................71
   SECTION 1603.  No Fractional Shares..................................................................71
   SECTION 1604.  Adjustment of Exchange Rate...........................................................72
   SECTION 1605.  Payment of Certain Taxes Upon Exchange................................................72
   SECTION 1606.  Shares Free and Clear.................................................................72
   SECTION 1607.  Cancellation of Security..............................................................72
   SECTION 1608.  Duties of Trustee Regarding Exchange..................................................73
   SECTION 1609.  Repayment of Certain Funds Upon Exchange..............................................73
   SECTION 1610.  Exercise of Conversion Privilege......................................................73
   SECTION 1611.  Effect of Consolidation or Merger on Conversion Privilege.............................74
ARTICLE SEVENTEEN - SUBORDINATION.......................................................................75
   SECTION 1701.  Agreement to Subordinate..............................................................75
   SECTION 1702.  Liquidation; Dissolution; Bankruptcy..................................................75
   SECTION 1703.  Default on Senior Debt................................................................76
   SECTION 1704.  Acceleration of Securities............................................................76
   SECTION 1705.  When Distribution Must Be Paid Over...................................................77
   SECTION 1706.  Notice by Company.....................................................................77
   SECTION 1707.  Subrogation...........................................................................77
   SECTION 1708.  Relative Rights.......................................................................77
   SECTION 1709.  Subordination May Not Be Impaired By Company..........................................78
   SECTION 1710.  Distribution or Notice to Representative..............................................78
   SECTION 1711.  Rights of Trustee and Paying Agent....................................................78
</TABLE>

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<TABLE>
<S>               <C>                                                                                   <C>
   SECTION 1712.  Payment Permitted in Certain Situations...............................................78
   SECTION 1713.  Trustee to Effectuate Subordination...................................................78
   SECTION 1714.  Reliance on Judicial Order or Certificate of Liquidating Agent........................78
   SECTION 1715.  Article Applicable to Paying Agents...................................................79
</TABLE>



                                     - iv -
<PAGE>   6
                          REGIONS FINANCIAL CORPORATION

Reconciliation and tie between Trust Indenture Act of 1939, as amended (the
"TIA"), and Indenture, dated as of ___________, 2001

<TABLE>
<CAPTION>

                                                                        Indenture
Trust Indenture Act Section                                             Section
---------------------------                                             ---------
<S>                                                                     <C>
Section 310(a)(1)                                                       607
               (a)(2)                                                   607
               (b)                                                      608
Section 312(c)                                                          701
Section 314(a)                                                          703
               (a)(4)                                                   1010
               (c)(1)                                                   102
               (c)(2)                                                   102
(e)      102
Section 315(b)                                                          601
Section 316(a)(last sentence)                                           101 ("Outstanding")
               (a)(1)(A)                                                502, 512
               (a)(1)(B)                                                513
               (b)                                                      508
Section 317(a)(1)                                                       503
               (a)(2)                                                   504
Section 318(a)                                                          112
               (c)                                                      112

</TABLE>

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

         Attention should also be directed to Section 318(c) of the TIA, which
         provides that the provisions of Sections 310 to and including 317 of
         the TIA are a part of and govern every qualified indenture, whether or
         not physically contained therein.


                                      -v-
<PAGE>   7
                                    INDENTURE

         INDENTURE, dated as of ______________, 2001, between REGIONS FINANCIAL
CORPORATION, a Delaware corporation (hereinafter called the "Company"), having
its principal office at 417 North 20th Street, Birmingham, Alabama 35203 and
BANKERS TRUST COMPANY, a New York banking corporation, as Trustee hereunder
(hereinafter called the "Trustee"), having its Corporate Trust Office at 4
Albany Street, 4th Floor, New York, New York 10006.

                             RECITALS OF THE COMPANY

         The Company deems it necessary to issue from time to time for its
lawful purposes its debt securities in series (hereinafter called the
"Securities") of substantially the tenor hereinafter provided evidencing its
unsecured and subordinated indebtedness, and has duly authorized the execution
and delivery of this Indenture to provide for the issuance from time to time of
the Securities, unlimited as to aggregate principal amount, to bear interest at
the rates or formulas, to mature at such times and to have such other provisions
as shall be fixed therefor as hereinafter provided.

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

                   NOW, THEREFORE, THIS INDENTURE WITNESSETH:

         For and in consideration of the premises and the purchase of the
Securities by the Holders thereof, it is mutually covenanted and agreed, for the
equal and proportionate benefit of all Holders of the Securities, as follows:

                                   ARTICLE ONE
             DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

SECTION 101.  Definitions.

         For all purposes of this Indenture, except as otherwise expressly
provided or the context otherwise requires:

         (1) the terms defined in this Article have the meanings assigned to
them in this Article, and include the plural as well as the singular;

         (2) all other terms used herein which are defined in the Trust
Indenture Act, either directly or by reference therein, have the meanings
assigned to them therein, and the terms "cash transaction" and "self-
liquidating paper," as used in Trust

         Indenture Act Section 311, shall have the meanings assigned to them in
the rules of the Commission adopted under the Trust Indenture Act;

         (3) all accounting terms not otherwise defined herein have the meanings
assigned to them in accordance with generally accepted accounting principles;
and

         (4) the words "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.

         Certain terms, used principally in Article Three, Article Five, Article
Six and Article Ten, are defined in those Articles. In addition, the following
terms shall have the indicated respective meanings:

         "Act" has the meaning specified in Section 104.
<PAGE>   8
         "Additional Amounts" means any additional amounts which are required by
a Security, under circumstances specified therein, to be paid by the Company in
respect of certain taxes imposed on certain Holders and which are owing to such
Holders in order that they receive the amount they would have received as if
such taxes had not been imposed.

         "Additional Interest" means the interest, if any, that shall accrue on
any interest on the Securities of any series the payment of which has not been
made on the applicable Interest Payment Date and which shall accrue at the rate
per annum specified or determined as specified in such Security.

         "Additional Sums" has the meaning specified in Section 1013.

         "Additional Taxes" means the sum of any additional taxes, duties and
other governmental charges to which a Regions Trust has become subject from time
to time as a result of a Tax Event.

         "Administrative Trustee" means, in respect of a Regions Trust, each
Person identified as an "Administrative Trustee" in the related Trust Agreement,
solely in such Person's capacity as Administrative Trustee of such Regions Trust
under such Trust Agreement and not in such Person's individual capacity, or any
successor Administrative Trustee appointed as therein provided.

         "Affiliate" of any specified Person means any other Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person; provided, however, no Regions Trust to which
Securities have been issued shall be deemed to be an Affiliate of the Company.
For the purposes of this definition, "control" when used with respect to any
specified Person means the power to direct the management and policies of such
Person, directly or indirectly, whether through the ownership of voting
securities, by contract or otherwise; and the terms "controlling" and
"controlled" have meanings correlative to the foregoing.

         "Authenticating Agent" means any authenticating agent appointed by the
Trustee pursuant to Section 611.

         "Authorized Newspaper" means a newspaper, printed in the English
language or in an official language of the country of publication, customarily
published on each Business Day, whether or not published on Saturdays, Sundays
or holidays, and of general circulation in each place in connection with which
the term is used or in the financial community of each such place. Whenever
successive publications are required to be made in Authorized Newspapers, the
successive publications may be made in the same or in different Authorized
Newspapers in the same city meeting the foregoing requirements and in each case
on any Business Day.

         "Bankruptcy Law" has the meaning specified in Section 501.

         "Bearer Security" means a Security issued hereunder which is payable to
bearer.

         "Board of Directors" means the Board of Directors of the Company, the
executive committee or any other committee or director of that board duly
authorized to act for it in respect hereof.

         "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 or a committee thereof, and to be in full force and
effect on the date of such certification, and delivered to the Trustee.

         "Business Day," when used with respect to any Place of Payment or any
other particular location referred to in this Indenture or in the Securities,
means, unless otherwise specified with respect to any Securities pursuant to
Section 301, any day, other than a Saturday or Sunday, that is neither a legal
holiday nor a day on which banking institutions in that Place of Payment or
particular location are authorized or required by law, regulation or executive
order to close, or, with respect to the Securities of a series initially issued
to a Regions Trust, the principal office of the Property Trustee under the
related Trust Agreement, is closed for business.


         "Capital Treatment Event" means the reasonable determination by the
Company that, as a result of the occurrence of any amendment to, or change
(including any announced proposed change) in, the laws (or any regulations
thereunder) of the United States or any political subdivision thereof or therein
or any rules, guidelines or policies of the Federal Reserve, or as a result of
any official or administrative pronouncement or action or judicial decision
interpreting or applying such laws, regulations, rules, guidelines or policies,
which amendment or change is effective or which proposed change, pronouncement,
action or decision is announced on or after the date of issuance of the
Preferred Securities under the Declaration, there is more than an insubstantial
risk that the Company will not be entitled to treat an amount equal to the
liquidation amount of the Preferred Securities as "Tier 1 Capital" (or the then
equivalent thereof) for purposes of the capital adequacy guidelines of the
Federal Reserve, as then in effect and applicable to the Company.


                                      -2-
<PAGE>   9

         "CEDEL" means Central de Livraison de Valeurs Mobilieres, S.A., or its
successor.

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

         "Common Depository" has the meaning specified in Section 304(b).

         "Common Securities" means the undivided common beneficial interests in
the Regions Trusts.

         "Company" means the Person named as the "Company" in the first
paragraph of this Indenture until a successor corporation shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
"Company" shall mean such successor corporation.

         "Company Request" and "Company Order" mean, respectively, a written
request or order signed in the name of the Company by the President or a Vice
President of the Company, and by the Treasurer, an Assistant Treasurer, the
Secretary or an Assistant Secretary of the Company, and delivered to the
Trustee.

         "Conversion Event" means the cessation of use of (i) a Foreign Currency
(other than as otherwise provided with respect to a Security pursuant to Section
301) as provided by the government of the country which issued such currency and
for the settlement of transactions by a central bank or other public
institutions of or within the international banking community or (ii) any
currency unit (or composite currency) for the purposes for which it was
established.

         "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 4 Albany Street, 4th
Floor, New York, New York 10006, or at any other time at such other address as
the Trustee may designate from time to time by notice to the Holders.

         "Corporation" includes corporations, associations, companies and
business trusts.

         "Coupon" means any interest coupon appertaining to a Bearer Security.

         "Custodian" has the meaning set forth in Section 501.

         "Debt" means the principal, premium, if any, unpaid interest (including
interest accruing on or after the filing of any petition in bankruptcy or for
reorganization relating to the Company whether or not a claim for post-filing
interest is allowed in such proceeding), fees, charges, expenses, reimbursement
and indemnification obligations, and all other amounts payable under or in
respect of the following indebtedness of the Company, whether any such
indebtedness exists as of the date of the Indenture or is created, incurred,
assumed or guaranteed after such date:

                  (i)   any debt (a) for money borrowed, or (b) evidenced by a
         bond, note, debenture, or similar instrument (including purchase money
         obligations) whether or not given in connection with the acquisition of
         any business, property or assets, whether by purchase, merger,
         consolidation or otherwise, but shall not include any account payable
         or other obligation created or assumed in the ordinary course of
         business in connection with the obtaining of materials or services, or
         (c) which is a direct or indirect obligation which arises as a result
         of banker's acceptances or bank letters of credit issued for the
         account of the Company;

                  (ii)  indebtedness secured by any mortgage, pledge, lien,
         charge, encumbrance or any security interest existing on property owned
         by the Company;


                                      -3-
<PAGE>   10
                  (iii) the obligation of the Company, as lessee under any lease
         of property that is or is required to be reflected on the Company's
         balance sheet as a capitalized lease in accordance with GAAP; and

                  (iv)  any deferral, amendment, renewal, extension, supplement,
         modification or refunding of any liability of the kind described in any
         of the preceding clauses (i), (ii) and (iii);

                  (v)   any obligation or debt described in the preceding
         clauses (i) through (iv) of another Person and all dividends of another
         Person the payment of which, in either case, the Company has guaranteed
         or for which the Company is responsible or liable, directly or
         indirectly, as obligor or otherwise;

       provided, however, that, in computing indebtedness of the Company, there
       shall be excluded any particular indebtedness if, (i) upon or prior to
       the maturity thereof, there shall have been deposited with an
       unaffiliated depository in trust money (or evidence of indebtedness if
       permitted by the instrument creating such indebtedness) in the necessary
       amount to pay, redeem or satisfy such indebtedness as it becomes due (or
       if applicable, as it may be redeemed prior to its stated maturity in
       accordance with the terms, if any, regarding early redemption set forth
       in the instrument governing such indebtedness), and the amount so
       deposited shall not be included in any computation of the assets of the
       Company and (ii) prior to such deposit the Company shall deliver an
       Officers' Certificate to the Trustee which shall certify that such amount
       has been so deposited with such depository.

         "Defaulted Interest" has the meaning specified in Section 307.

         "Depository" when used with respect to the Securities of or within any
series issuable or issued in whole or in part in global form, means the Person
designated as Depository by the Company pursuant to Section 301 until a
successor Depository shall have become such pursuant to the applicable
provisions of this Indenture, and thereafter shall mean or include each Person
which is then a Depository hereunder, and if at any time there is more than one
such Person, shall be a collective reference to such Persons.

         "Distributions," with respect to the Trust Securities issued by a
Regions Trust, means amounts payable in respect of such Trust Securities as
provided in the related Trust Agreement and referred to therein as
"Distributions."

         "Dollar" or "$" means a dollar or other equivalent unit in such coin or
currency of the United States of America as at the time shall be legal tender
for payment of public and private debts.

         "DTC" means The Depository Trust Company.

         "Euroclear" means Morgan Guaranty Trust Company of New York, Brussels
Office, or its successor as operator of the Euroclear System, Clearstream
Banking, societe anonyme, Luxembourg.

         "Event of Default" has the meaning specified in Section 501.

         "Expiration Date" means any date designated as such pursuant to Section
104(h) hereof.

         "Extension Period" has the meaning specified in Section 311.

         "Exchange Act" means the Securities Exchange Act of 1934, as amended,
and the rules and regulations promulgated thereunder by the Commission.

         "Exchange Rate Agent" unless otherwise specified with respect to
Securities of or within any series pursuant to Section 301, means a bank
designated as such in accordance with Section 301 (which may include any such
bank acting as Trustee).


                                      -4-
<PAGE>   11
         "Exchange Rate Officer's Certificate" means a certificate in the form
attached as Exhibit B setting forth (i) the applicable market exchange rate or
the applicable bid quotation and (ii) the Dollar or Foreign Currency amounts of
principal (and premium, if any) and interest, if any (on an aggregate basis and
on the basis of a Security having the lowest denomination principal amount in
the relevant currency or currency unit), payable with respect to a Security of
any series on the basis of such market exchange rate or the applicable bid
quotation, signed by the Chief Financial Officer, Treasurer, or any Vice
President of the Company.

         "Foreign Currency" means any currency, currency unit or composite
currency issued by the government of one or more countries other than the United
States of America or by any recognized confederation or association of such
governments.

         "GAAP" means generally accepted accounting principles as used in the
United States applied on a consistent basis as in effect from time to time;
provided that solely for purposes of any calculation required by the financial
covenants contained herein, "GAAP" shall mean generally accepted accounting
principles as used in the United States on the date hereof, applied on a
consistent basis.

         "Government Obligations" means securities which are (i) direct
obligations of the United States of America or, if specified as contemplated by
Section 301, the government which issued the Foreign Currency in which the
Securities of a particular series are payable, for the payment of which its full
faith and credit is pledged or (ii) obligations of a Person controlled or
supervised by and acting as an agency or instrumentality of the United States of
America or, if specified as contemplated by Section 301, such government which
issued the Foreign Currency in which the Securities of such series are payable,
the payment of which is unconditionally guaranteed as a full faith and credit
obligation by the United States of America or such other government, which, in
either case, are not callable or redeemable at the option of the issuer thereof,
and shall also include a depository receipt issued by a bank or trust company as
custodian with respect to any such Government Obligation or a specific payment
of interest on or principal of any such Government Obligation held by such
custodian for the account of the holder of a depository receipt, provided that
(except as required by law) such custodian is not authorized to make any
deduction from the amount payable to the holder of such depository receipt from
any amount received by the custodian in respect of the Government Obligation or
the specific payment of interest on or principal of the Government Obligation
evidenced by such depository receipt.

         "Holder" means, in the case of a Registered Security, the Person in
whose name a Security is registered in the Security Register and, in the case of
a Bearer Security, the bearer thereof and, when used with respect to any coupon,
shall mean the bearer thereof.

         "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 pursuant to the applicable provisions hereof,
and shall include the terms of particular series of Securities established as
contemplated by Section 301; provided, however, that, if at any time more than
one Person is acting as Trustee under this instrument, "Indenture" shall mean,
with respect to any one or more series of Securities for which such Person is
Trustee, 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 pursuant to the applicable provisions hereof and shall include the terms of
the or those particular series of Securities for which such Person is Trustee
established as contemplated by Section 301, exclusive, however, of any
provisions or terms which relate solely to other series of Securities for which
such Person is not Trustee, regardless of when such terms or provisions were
adopted, and exclusive of any provisions or terms adopted by means of one or
more indentures supplemental hereto executed and delivered after such Person had
become such Trustee but to which such Person, as such Trustee, was not a party.

         "Indexed Security" means a Security the terms of which provide that the
principal amount thereof payable at Stated Maturity may be more or less than the
principal face amount thereof at original issuance.

         "Interest" when used with respect to an Original Issue Discount
Security which by its terms bears interest only after Maturity, shall mean
interest payable after Maturity, and, when used with respect to a


                                      -5-
<PAGE>   12
Security which provides for the payment of Additional Amounts pursuant to
Section 1011, includes such Additional Amounts.

         "Interest Payment Date" means, when used with respect to any Security,
the Stated Maturity of an installment of interest on such Security.

         "Investment Company Event" means the receipt by a Regions Trust of an
Opinion of Counsel to the Company experienced in such matters to the effect
that, as a result of the occurrence of a change in law or regulation or a
written change (including any announced prospective change) in interpretation or
application of law or regulation by any legislative body, court, governmental
agency or regulatory authority, there is more than an insubstantial risk that
such Regions Trust is or will be considered an "investment company" that is
required to be registered under the Investment Company Act of 1940, as amended
(the "Investment Company Act"), which change or prospective change becomes
effective or would become effective, as the case may be, on or after the date of
the issuance of the Preferred Securities.

         "Make-Whole Amount" means the amount, if any, in addition to principal
which is required by a Security, under the terms and conditions specified
therein or as otherwise specified as contemplated by Section 301, to be paid by
the Company to the Holder thereof in connection with any optional redemption or
accelerated payment of such Security.

         "Maturity" means, when used with respect to any Security, the date on
which the principal of such Security or an installment of principal becomes due
and payable as therein or herein provided, whether at the Stated Maturity or by
declaration of acceleration, notice of redemption, notice of option to elect
repayment, repurchase or otherwise.

         "Officers' Certificate" means a certificate signed by the President or
a Vice President and by the Treasurer, an Assistant Treasurer, the Secretary or
an Assistant Secretary, of the Company, and delivered to the Trustee.

         "Opinion of Counsel" means a written opinion of counsel, who may be an
employee of or counsel for the Company or other counsel satisfactory to the
Trustee.

         "Original Issue Discount Security" means any Security which provides
for an amount less than the principal amount thereof to be due and payable upon
a declaration of acceleration of the Maturity thereof pursuant to Section 502.

         "Outstanding," when used with respect to Securities, means, as of the
date of determination, all Securities theretofore authenticated and delivered
under this Indenture, except:

                  (i)   Securities theretofore canceled by the Trustee or
         delivered to the Trustee for cancellation;

                  (ii)  Securities, or portions thereof, for whose payment or
         redemption or repayment at the option of the Holder money in the
         necessary amount and the required currency has been theretofore
         deposited with the Trustee or any Paying Agent (other than the Company)
         in trust or set aside and segregated in trust by the Company (if the
         Company shall act as its own Paying Agent) for the Holders of such
         Securities and any coupons appertaining thereto; provided that, if such
         Securities are to be redeemed, notice of such redemption has been duly
         given pursuant to this Indenture or other provision therefor
         satisfactory to the Trustee has been made;

                  (iii) Securities, except solely to the extent provided in
         Sections 1402 or 1403, as applicable, with respect to which the Company
         has effected defeasance and/or covenant defeasance as provided in
         Article Fourteen;

                  (iv)  Securities which have been paid pursuant to Section 306
         or in exchange for or in lieu of which other Securities have been
         authenticated and delivered pursuant to this Indenture, other


                                      -6-
<PAGE>   13
         than any such Securities in respect of which there shall have been
         presented to the Trustee proof satisfactory to it that such Securities
         are held by a bona fide purchaser in whose hands such Securities are
         valid obligations of the Company; and

                  (v)   Securities converted or exchanged into other securities
         or property of the Company pursuant to or in accordance with this
         Indenture if the terms of such Securities provide for convertibility or
         exchange pursuant to Section 301; provided, however, that in
         determining whether the Holders of the requisite principal amount of
         the Outstanding Securities have given any request, demand,
         authorization, direction, notice, consent or waiver hereunder or are
         present at a meeting of Holders for quorum purposes, and for the
         purpose of making the calculations required by Trust Indenture Act
         Section 313, (a) the principal amount of an Original Issue Discount
         Security that may be counted in making such determination or
         calculation and that shall be deemed to be Outstanding for such purpose
         shall be equal to the amount of principal thereof that would be (or
         shall have been declared to be) due and payable, at the time of such
         determination, upon a declaration of acceleration of the maturity
         thereof pursuant to Section 502, (b) the principal amount of any
         Security denominated in a Foreign Currency that may be counted in
         making such determination or calculation and that shall be deemed
         Outstanding for such purpose shall be equal to the Dollar equivalent,
         determined pursuant to Section 301 as of the date such Security is
         originally issued by the Company as set forth in an Exchange Rate
         Officer's Certificate delivered to the Trustee, of the principal amount
         (or, in the case of an Original Issue Discount Security, the Dollar
         equivalent as of such date of original issuance of the amount
         determined as provided in clause (a) above) of such Security, (c) the
         principal amount of any Indexed Security that may be counted in making
         such determination or calculation and that shall be deemed outstanding
         for such purpose shall be equal to the principal face amount of such
         Indexed Security at original issuance, unless otherwise provided with
         respect to such Indexed Security pursuant to Section 301, and (d)
         Securities owned by the Company or any other obligor upon the
         Securities or any Affiliate of the Company or of such other obligor
         shall be disregarded and deemed not to be Outstanding, except that, in
         determining whether the Trustee shall be protected in making such
         calculation or in relying upon any such request, demand, authorization,
         direction, notice, consent or waiver, only Securities which a
         Responsible Officer of the Trustee actually knows to be so owned shall
         be so disregarded. Securities so owned which have been pledged in good
         faith may be regarded as Outstanding if the pledgee establishes to the
         satisfaction of the Trustee the pledgee's right so to act with respect
         to such Securities and that the pledgee is not the Company or any other
         obligor upon the Securities or any Affiliate of the Company or of such
         other obligor.

         "Paying Agent" means any Person authorized by the Company to pay the
principal of (and premium or Make-Whole Amount, if any), interest or any other
payments on any Securities, or coupons on behalf of the Company, or if no such
Person is authorized, the Company.

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

         "Place of Payment" means, when used with respect to the Securities of
or within any series, the place or places where the principal of (and premium or
Make-Whole Amount, if any) interest, and any other payment on such Securities
are payable as specified as contemplated by Sections 301 and 1002.

         "Predecessor Security" of any particular Security means every previous
Security evidencing all or a portion of the same debt as that evidenced by such
particular Security; and, for the purposes of this definition, any Security
authenticated and delivered under Section 306 in exchange for or in lieu of a
mutilated, destroyed, lost or stolen Security or a Security to which a
mutilated, destroyed, lost or stolen coupon appertains shall be deemed to
evidence the same debt as the mutilated, destroyed, lost or stolen Security or
the Security to which the mutilated, destroyed, lost or stolen coupon
appertains.

         "Preferred Securities" means undivided preferred beneficial interests
in the Regions Trusts.


                                      -7-
<PAGE>   14
         "Principal Subsidiary Bank" means any Subsidiary Bank, the consolidated
assets of which constitute 50% or more of the consolidated assets of the
Company.

         "Property Trustee" means, in respect of any Regions Trust, the
commercial bank or trust company identified as the "Property Trustee" in the
related Trust Agreement, solely in its capacity as Property Trustee of such
Regions Trust under such Trust Agreement and not in its individual capacity, or
its successor in interest in such capacity, or any successor property trustee
appointed as therein provided.

         "Redemption Date" means, when used with respect to any security to be
redeemed in whole or in part, the date fixed for such redemption by or pursuant
to this Indenture.

         "Redemption Price" means, when used with respect to any Security to be
redeemed in whole or in part, the price at which it is to be redeemed pursuant
to this Indenture.

         "Regions Guarantee" means the guarantee by the Company of distributions
on the Preferred Securities of a Regions Trust to the extent provided in a
guarantee agreement.

         "Regions Trust" means one or more business trusts, partnerships or
limited liability companies created by the Company for the purpose of issuing
undivided beneficial interests therein in connection with the purchase of
Securities under this Indenture.

         "Registered Security" means any Security which is registered in the
Security Register.

         "Regular Record Date" for the installment of interest payable on any
Interest Payment Date on the Registered Securities of or within any series means
the date specified for that purpose as contemplated by Section 301, whether or
not a Business Day.

         "Repayment Date" means, when used with respect to any Security to be
repaid or repurchased at the option of the Holder, the date fixed for such
repayment or repurchase by or pursuant to this Indenture.

         "Repayment Price" means, when used with respect to any Security to be
repaid or purchased at the option of the Holder, the price at which it is to be
repaid or repurchased pursuant to this Indenture.

         "Representative" means the indenture trustee or other trustee, agent or
representative for an issue of Senior Debt.

         "Responsible Officer" means, with respect to the Trustee, any officer
within the Corporate Trust Office including any vice president, assistant vice
president, managing director, assistant treasurer, secretary, assistant
secretary or any other officer of the Trustee customarily performing functions
similar to those performed by any of the above designated officers and having
direct responsibility for the administration of this Indenture, and also, with
respect to a particular matter, any other officer to whom such matter is
referred because of such officer's knowledge of and familiarity with the
particular subject.

         "Securities Act" means the Securities Act of 1933, as amended, and the
rules and regulations promulgated thereunder by the Commission.

         "Security" has the meaning stated in the first recital of this
Indenture and, more particularly, means any Security or Securities authenticated
and delivered under this Indenture; provided, however, that if at any time there
is more than one Person acting as Trustee under this Indenture, "Securities"
with respect to the Indenture as to which such Person is Trustee shall have the
meaning stated in the first recital of this


                                      -8-
<PAGE>   15
Indenture and shall more particularly mean Securities authenticated and
delivered under this Indenture, exclusive, however, of Securities of or within
any series as to which such Person is not Trustee.

         "Security Register" and "Security Registrar" have the respective
meanings specified in Section 305.

         "Senior Debt" means the principal, premium, if any, unpaid interest
(including interest accruing on or after the filing of any petition in
bankruptcy or for reorganization relating to the Company whether or not a claim
for post-filing interest is allowed in such proceeding), fees, charges,
expenses, reimbursement and indemnification obligations, and all other amounts
payable under or in respect of (i) Debt and (ii) all obligations to make payment
pursuant to the terms of financial instruments, such as (x) securities contracts
and foreign currency exchange contracts, (y) derivative instruments, such as
swap agreements (including interest rate and foreign exchange rate swap
agreements), cap agreements, floor agreements, collar agreements, interest rate
agreements, foreign exchange rate agreements, options, commodity futures
contracts, commodity option contracts, and (z) in the case of both (x) and (y)
above, similar financial instruments, in each case, whether any such
indebtedness exists as of the date of the Indenture or is created, incurred,
assumed or guaranteed after such date and any such obligation of another Person
the payment of which, in either case, the Company has guaranteed or for which
the Company is responsible or liable, directly or indirectly, as obligor or
otherwise; provided, however, that, in any event, Senior Debt shall not include
(1) any such indebtedness, obligation or liability referred to in clauses (i)
through (v) of the definition of Debt as to which, in the instrument creating or
evidencing the same or pursuant to which the same is outstanding, it is provided
that such indebtedness, obligation or liability is not superior in right of
payment to the Securities, or ranks pari passu with the Securities, (2) the
Securities, (3) 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, (4) any Debt of the
Company for wages or bank deposits payable to the Company's executive officers
and directors; (5) any Debt to any employee of the Company, and (6) all other
indebtedness of the Company sold to any Subsidiary of the Company, including any
limited liability companies, partnerships or trusts established or to be
established by the Company, in each case where such Subsidiary is a financing
entity of the Company in connection with the issuance by such financing entity
of securities that are similar to the Preferred Securities.

         "Significant Subsidiary" means any Subsidiary which is a "significant
subsidiary" (within the meaning of Regulation S-X, promulgated under the
Securities Act) of the Company. The term Significant Subsidiary shall not
include any Regions Trust, but shall in any event include any Principal Bank
Subsidiary.

         "Special Record Date" for the payment of any Defaulted Interest on the
Registered Securities of or within any series means a date fixed by the Trustee
pursuant to Section 307.

         "Stated Maturity" means, when used with respect to any Security or any
installment of principal thereof or interest thereon, the date specified in such
Security or a coupon representing such installment of interest as the fixed date
on which the principal of such Security or such installment of principal or
interest is due and payable.

         "Subsidiary" means, with respect to any Person, (a) any corporation or
other entity of which a majority of (i) the voting power of the voting equity
securities or (ii) the outstanding equity interests of which are owned, directly
or indirectly, by such Person, or (b) any other Person which is otherwise
controlled by such Person or by one or more other Subsidiaries of such Person or
by such Person and one or more other Subsidiaries of such Person. For the
purposes of this definition, "voting equity securities" means equity securities
having voting power for the election of directors, or other similar entity
whether at all times or only so long as no senior class of security has such
voting power by reason of any contingency.

         "Subsidiary Bank" means any Subsidiary of the Company which is a bank
or trust company organized and doing business under any state or federal law.


                                      -9-
<PAGE>   16
         "Tax Event" means the receipt by a Regions 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 Preferred Securities of such Regions Trust, there is more than an
insubstantial risk that (i) such Regions Trust is, or will be within 90 days of
the date of such Opinion of Counsel, subject to United States Federal income tax
with respect to income received or accrued on the corresponding series of
Securities issued by the Company to such Regions Trust, (ii) interest payable by
the Company or original issue discount on such corresponding series of
Securities is not, or within 90 days of 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 or (iii) such Regions Trust is, or will be within 90
days of the date of such Opinion of Counsel, subject to more than a de minimis
amount of other taxes, duties or other governmental charges.

         "Trust Agreement" means the Declaration of Trust (or an Amended and
Restated Trust Agreement) under which a Regions Trust is created (or continued)
and providing for the issuance of Trust Securities by such Regions Trust, as
amended from time to time.

         "Trust Indenture Act" or "TIA" means the Trust Indenture Act of 1939,
as amended and as in force at the date as of which this Indenture was executed,
except as provided in Section 905.

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

         "Trustee" means the Person named as the "Trustee" in the first
paragraph of this Indenture until a successor Trustee shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
"Trustee" shall mean or include each Person who is then a Trustee hereunder;
provided, however, that if at any time there is more than one such Person,
"Trustee" as used with respect to the Securities of or within any series shall
mean only the Trustee with respect to the Securities of that series.

         "United States" means, unless otherwise specified with respect to any
Securities pursuant to Section 301, the United States of America (including the
states and the District of Columbia), its territories, its possessions and other
areas subject to its jurisdiction.

         "United States person" means, unless otherwise specified with respect
to any Securities pursuant to Section 301, an individual who is a citizen or
resident of the United States, a corporation, partnership or other entity
created or organized in or under the laws of the United States or any state or
the District of Columbia or an estate or trust the income of which is subject to
United States federal income taxation regardless of its source.

         "Yield to Maturity" means the yield to maturity, computed at the time
of issuance of a Security (or, if applicable, at the most recent
predetermination of interest on such Security) and as set forth in such Security
in accordance with generally accepted United States bond yield computation
principles.

SECTION 102.  Compliance Certificates and Opinions.

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


                                      -10-
<PAGE>   17
         Every certificate or opinion with respect to compliance with a
condition or covenant provided for in this Indenture (excluding certificates
delivered pursuant to Section 1010) shall include:

                  (1) a statement that each individual signing such certificate
or opinion has read such condition or covenant and the definitions herein
relating thereto;

                  (2) 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;

                  (3) a statement that, in the opinion of each such individual,
he has made such examination or investigation as is necessary to enable him to
express an informed opinion as to whether or not such condition or covenant has
been complied with; and

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

SECTION 103.  Form of Documents Delivered to Trustee.

         In any case where several matters are required to be certified by, or
covered by an opinion of, any specified Person, it is not necessary that all
such matters be certified by, or covered by the opinion of, only one such
Person, or that they be so certified or covered by only one document, but one
such Person may certify or give an opinion as to some matters and one or more
other such Persons as to other matters, and any such Person may certify or give
an opinion as to such matters in one or several documents.

         Any certificate or opinion of an officer of the Company may be based,
insofar as it relates to legal matters, upon an Opinion of Counsel, or a
certificate or representations by counsel, unless such officer knows, or in the
exercise of reasonable care should know, that the opinion, certificate or
representations with respect to the matters upon which his certificate or
opinion is based are erroneous. Any such Opinion of Counsel or certificate or
representations may be based, insofar as it relates to factual matters, upon a
certificate or opinion of, or representations by, an officer or officers of the
Company stating that the information as to such factual matters is in the
possession of the Company, unless such counsel knows that the certificate or
opinion or representations as to such matters are erroneous.

         Where any Person is required to make, give or execute two or more
applications, requests, consents, certificates, statements, opinions or other
instruments under this Indenture, they may, but need not, be consolidated and
form one instrument.

SECTION 104.  Acts of Holders.

         (a) Any request, demand, authorization, direction, notice, consent,
waiver or other action provided by this Indenture to be given or taken by
Holders of the Outstanding Securities of all series or one or more series, as
the case may be, may be embodied in and evidenced by one or more instruments of
substantially similar tenor signed by such Holders in person or by agents duly
appointed in writing. If Securities of a series are issuable as Bearer
Securities, any request, demand, authorization, direction, notice, consent,
waiver or other action provided by this Indenture to be given or taken by
Holders of Securities of such series may, alternatively, be embodied in and
evidenced by the record of Holders of Securities of such series voting in favor
thereof, whether in person or by proxies duly appointed in writing, at any
meeting of Holders of Securities of such series duly called and held in
accordance with the provisions of Article Fifteen, or a combination of such
instruments and any such record. Except as herein otherwise expressly provided,
such action shall become effective when such instrument or instruments or record
or both are delivered to the Trustee and, where it is hereby expressly required,
to the Company. Such instrument or instruments and any such record (and the
action embodied therein and evidenced thereby) are herein sometimes referred to
as the "Act" of the Holders signing such instrument or instruments or so voting
at any such meeting. Proof of execution of any such instrument or of a writing
appointing any such agent, or of the holding by any Person of a Security, shall
be sufficient for any purpose of this Indenture and (subject to Section 612)
conclusive in favor of the Trustee and the Company and any agent of the Trustee
or the


                                      -11-
<PAGE>   18
Company, if made in the manner provided in this Section. The record of any
meeting of Holders of Securities shall be proved in the manner provided in
Section 1506.

         (b) The fact and date of the execution by any Person of any such
instrument or writing may be proved by the affidavit of a witness of such
execution or by a certificate of a notary public or other officer authorized by
law to take acknowledgments of deeds, certifying that the individual signing
such instrument or writing acknowledged to him the execution thereof. Where such
execution is by a signer acting in a capacity other than his individual
capacity, such certificate or affidavit shall also constitute sufficient proof
of his authority. The fact and date of the execution of any such instrument or
writing, or the authority of the Person executing the same, may also be proved
in any other reasonable manner which the Trustee deems sufficient.

         (c) The ownership of Registered Securities shall be proved by the
Security Register or by a certificate of the Security Registrar.

         (d) The ownership of Bearer Securities may be proved by the production
of such Bearer Securities or by a certificate executed, as depository, by any
trust company, bank, banker or other depository, wherever situated, if such
certificate shall be deemed by the Trustee to be satisfactory, showing that at
the date therein mentioned such person had on deposit with such depository, or
exhibited to it, the Bearer Securities therein described; or such facts may be
proved by the certificate or affidavit of the Person holding such Bearer
Securities, if such certificate or affidavit is deemed by the Trustee to be
satisfactory. The Trustee and the Company may assume that such ownership of any
Bearer Security continues until (1) another certificate or affidavit bearing a
later date issued in respect of the same Bearer Security is produced, or (2)
such Bearer Security is produced to the Trustee by some other Person, or (3)
such Bearer Security is surrendered in exchange for a Registered Security, or
(4) such Bearer Security is no longer Outstanding. The ownership of Bearer
Securities may also be proved in any other manner which the Trustee deems
sufficient.

         (e) If the Company shall solicit from the Holders of Registered
Securities any request, demand, authorization, direction, notice, consent,
waiver or other Act, the Company may, at its option, in or pursuant to a Board
Resolution, fix in advance a record date for the determination of Holders
entitled to give such request, demand, authorization, direction, notice,
consent, waiver or other Act, but the Company shall have no obligation to do so.
Notwithstanding TIA Section 316(c), such record date shall be the record date
specified in or pursuant to such Board Resolution, which shall be a date not
earlier than the date 30 days prior to the first solicitation of Holders
generally in connection therewith and not later than the date such solicitation
is completed. If such a record date is fixed, such request, demand,
authorization, direction, notice, consent, waiver or other Act may be given
before or after such record date, but only the Holders of record at the close of
business on such record date shall be deemed to be Holders for the purposes of
determining whether Holders of the requisite proportion of Outstanding
Securities have authorized or agreed or consented to such request, demand,
authorization, direction, notice, consent, waiver or other Act, and for that
purpose the Outstanding Securities shall be computed as of such record date;
provided that no such authorization, agreement or consent by the Holders on such
record date shall be deemed effective unless it shall become effective pursuant
to the provisions of this Indenture not later than eleven months after the
record date.

         (f) Any request, demand, authorization, direction, notice, consent,
waiver or other Act of the Holder of any Security shall bind every future Holder
of the same Security and the Holder of every Security issued upon the
registration of transfer thereof or in exchange therefor or in lieu thereof in
respect of anything done, omitted or suffered to be done by the Trustee, any
Security Registrar, any Paying Agent, any Authenticating Agent or the Company in
reliance thereon, whether or not notation of such action is made upon such
Security.

         (g) The Trustee may, in its sole discretion, set any day as a record
date for the purpose of determining the Holders of Outstanding Securities of any
series entitled to join in the giving or making of (i) any Notice of Default,
(ii) any declaration of acceleration referred to in Section 502, (iii) any
request to institute proceedings referred to in Section 507(2) or (iv) any
direction referred to in Section 512, in each


                                      -12-
<PAGE>   19
case with respect to Securities of such series. If any record date is set
pursuant to this paragraph, the Holders of Outstanding Securities of such series
on such record date, and no other Holders, shall be entitled to join in such
notice, declaration, request or direction, whether or not such Holders remain
Holders after such record date, provided that no such action shall be effective
hereunder unless taken on or prior to the applicable Expiration Date by Holders
of the requisite principal amount of Outstanding Securities of such series on
such record date. Nothing in this paragraph shall be construed to prevent the
Trustee from setting a new record date for any action for which a record date
has previously been set pursuant to this paragraph (whereupon the record date
previously set shall automatically and with no action by any Person be cancelled
and of no effect), and nothing in this paragraph shall be construed to render
ineffective any action taken by Holders of the requisite principal amount of
Outstanding Securities of the relevant series on the date such action is taken.
Promptly after any record date is set pursuant to this paragraph, the Trustee,
at the Company's expense, shall cause notice of such record date, the proposed
action by Holders and the applicable Expiration

         Date to be given to the Company in writing and to each Holder of
Securities of the relevant series in the manner set forth in Section 106.

         (h) With respect to any record date set pursuant to this Section, the
party hereto which sets such record dates may designate any day as the
"Expiration Date" and from time to time may change the Expiration Date to any
earlier or later day; provided that no such change shall be effective unless
notice of the proposed new Expiration Date is given to the other party hereto in
writing, and to each Holder of Securities of the relevant series in the manner
set forth in Section 106, on or prior to the existing Expiration Date. If an
Expiration Date is not designated with respect to any record date set pursuant
to this Section, the party hereto which set such record date shall be deemed to
have initially designated the 180/th/ day after such record date as the
Expiration Date with respect thereto, subject to its right to change the
Expiration Date as provided in this paragraph. Notwithstanding the foregoing, no
Expiration Date shall be later than the 180/th/ day after the applicable record
date.

         Without limiting the foregoing, a Holder entitled hereunder to take any
action hereunder with regard to any particular Security may do so with regard to
all or any part of the principal amount of such Security or by one or more duly
appointed agents each of which may do so pursuant to such appointment with
regard to all or any part of such principal amount.

SECTION 105.  Notices, etc., the Trustee and Company.

         Any request, demand, authorization, direction, notice, consent, waiver
or Act of Holders or other document provided or permitted by this Indenture to
be made upon, given or furnished to or filed with,

         (1) the Trustee by any Holder or by the Company shall be sufficient for
every purpose hereunder if made, given, furnished or filed in writing to or with
the Trustee at its Corporate Trust Office, Attention: Corporate Trustee
Administration, or

         (2) the Company by the Trustee or by any Holder shall be sufficient for
every purpose hereunder (unless otherwise herein expressly provided) if in
writing and mailed, first class postage prepaid, to the Company addressed to it
at the address of its principal office specified in the first paragraph of this
Indenture or at any other address previously furnished in writing to the Trustee
by the Company.

SECTION 106.  Notice to Holders; Waiver.

         Where this Indenture provides for notice of any event to Holders of
Registered Securities by the Company or the Trustee, such notice shall be
sufficiently given (unless otherwise herein expressly provided) if in writing
and mailed, first-class postage prepaid, to each such Holder affected by such
event, at his address as it appears in the Security Register, not later than the
latest date, and not earlier than the earliest date, prescribed for the giving
of such notice. In any case where notice to Holders of Registered Securities is
given by mail, neither the failure to mail such notice, nor any defect in any
notice so mailed, to any particular Holder shall affect the sufficiency of such
notice with respect to other Holders of Registered


                                      -13-
<PAGE>   20
Securities or the sufficiency of any notice to Holders of Bearer Securities
given as provided herein. Any notice mailed to a Holder in the manner herein
prescribed shall be conclusively deemed to have been received by such Holder,
whether or not such Holder actually receives such notice.

         If by reason of the suspension of or irregularities in regular mail
service or by reason of any other cause it shall be impracticable to give such
notice by mail, then such notification to Holders of Registered Securities as
shall be made with the approval of the Trustee shall constitute a sufficient
notification to such Holders for every purpose hereunder.

         Except as otherwise expressly provided herein or otherwise specified
with respect to any Securities pursuant to Section 301, where this Indenture
provides for notice to Holders of Bearer Securities of any event, such notice
shall be sufficiently given if published in an Authorized Newspaper in The City
of New York and in such other city or cities as may be specified in such
Securities, and if the Securities of such series are listed on any stock
exchange outside the United States, in any place at which such Securities are
listed on a securities exchange to the extent that such securities exchange so
requires, on a Business Day, such publication to be not later than the latest
date, and not earlier than the earliest date, prescribed for the giving of such
notice. Any such notice shall be deemed to have been given on the date of such
publication or, if published more than once, on the date of the first such
publication.

         If by reason of the suspension of publication of any Authorized
Newspaper or Authorized Newspapers or by reason of any other cause it shall be
impracticable to publish any notice to Holders of Bearer Securities as provided
above, then such notification to Holders of Bearer Securities as shall be given
with the approval of the Trustee shall constitute sufficient notice to such
Holders for every purpose hereunder. Neither the failure to give notice by
publication to any particular Holder of Bearer Securities as provided above, nor
any defect in any notice so published, shall affect the sufficiency of such
notice with respect to other Holders of Bearer Securities or the sufficiency of
any notice to Holders of Registered Securities given as provided herein.

         Any request, demand, authorization, direction, notice, consent or
waiver required or permitted under this Indenture shall be in the English
language, except that any published notice may be in an official language of the
country of publication.

         Where this Indenture provides for notice in any manner, such notice may
be waived in writing by the Person entitled to receive such notice, either
before or after the event, and such waiver shall be the equivalent of such
notice. Waivers of notice by Holders shall be filed with the Trustee, but such
filing shall not be a condition precedent to the validity of any action taken in
reliance upon such waiver.

SECTION 107.  Effect of Headings and Table of Contents.

         The Article and Section headings herein and the Table of Contents are
for convenience only and shall not affect the construction hereof.

SECTION 108.  Successors and Assigns.

         All covenants and agreements in this Indenture by the Company shall
bind its successors and assigns, whether so expressed or not.

SECTION 109.  Separability Clause.

         In case any provision in this Indenture or in any Security or coupon
shall be invalid, illegal or unenforceable, the validity, legality and
enforceability of the remaining provisions shall not in any way be affected or
impaired thereby.


                                      -14-
<PAGE>   21
SECTION 110.  Benefits of Indenture.

         Nothing in this Indenture or in the Securities or coupons appertaining
thereto, express or implied, shall give to any Person, other than the parties
hereto, any Security Registrar, any Paying Agent, any Authenticating Agent and
their successors hereunder, the holders of Senior Debt and the Holders and, to
the extent expressly provided in any Trust Agreement, the Holders of Preferred
Securities, any benefit or any legal or equitable right, remedy or claim under
this Indenture.

SECTION 111.  No Personal Liability.

         No recourse under or upon any obligation, covenant or agreement
contained in this Indenture, in any Security or coupon appertaining thereto, or
because of any indebtedness evidenced thereby, shall be had against any
promoter, as such, or against any past, present or future shareholder, officer
or director, as such, of the Company or of any successor, either directly or
through the Company or any successor, under any rule of law, statute or
constitutional provision or by the enforcement of any assessment or by any legal
or equitable proceeding or otherwise, all such liability being expressly waived
and released by the acceptance of the Securities by the Holders thereof and as
part of the consideration for the issue of the Securities.

SECTION 112.  Governing Law.

         This Indenture and the Securities and coupons shall be governed by and
construed in accordance with the laws of the State of New York. This Indenture
is subject to the provisions of the TIA that are required to be part of this
Indenture and shall, to the extent applicable, be governed by such provisions
and any provisions of this Indenture that are not permitted by the provisions of
the TIA shall be deemed to be deleted or modified to the extent such provisions
are required to be deleted or modified for the Indenture to be qualified under
the TIA.

SECTION 113.  Legal Holidays.

         In any case where any Interest Payment Date, Redemption Date, Repayment
Date, sinking fund payment date, Stated Maturity or Maturity of any Security or
the last date on which a Holder has the right to convert or exchange a Security
at a particular conversion or exchange price shall not be a Business Day at any
Place of Payment, then (notwithstanding any other provision of this Indenture or
any Security or coupon other than a provision in the Securities of any series
which specifically states that such provision shall apply in lieu hereof),
payment of interest or any Additional Amounts or principal (and premium or
Make-Whole Amount, if any) need not be made at such Place of Payment on such
date, conversion or exchange need not be made at such Place of Payment on such
date, but may be made on the next succeeding Business Day at such Place of
Payment with the same force and effect as if made on the Interest Payment Date,
Redemption Date, Repayment Date or sinking fund payment date, or at the Stated
Maturity or Maturity or on such last day for conversion or exchange, provided
that so long as such payment is made on the next succeeding Business Day, no
interest shall accrue on the amount so payable for the period from and after
such Interest Payment Date, Redemption Date, Repayment Date, sinking fund
payment date, Stated Maturity or Maturity or on such last day for conversion or
exchange, as the case may be, to such Business Day.

                                   ARTICLE TWO
                                SECURITIES FORMS

SECTION 201.  Forms of Securities.

         The Registered Securities, if any, of each series and the Bearer
Securities, if any, and related coupons of each series, shall be in
substantially the forms as shall be established in or pursuant to one or more
indentures supplemental hereto or Board Resolutions, shall have such appropriate
insertions, omissions, substitutions and other variations as are required or
permitted by this Indenture or any indenture supplemental hereto, and may have
such letters, numbers or other marks of identification or designation and such
legends or endorsements placed thereon as the Company may deem appropriate and
as are not inconsistent with the provisions of this Indenture, or as may be
required to comply with any law or with


                                      -15-
<PAGE>   22
any rule or regulation made pursuant thereto or with any rule or regulation of
any stock exchange on which the Securities may be listed or Depository therefor,
or to conform to usage. If temporary Securities of any series are issued as
permitted by Section 304, the form thereof also shall be established as provided
by the preceding sentence. If the forms of Securities and coupons, if any, of
any series are established by, or by action taken pursuant to, a Board
Resolution, a copy of the Board Resolution together with an appropriate record
of any such action taken pursuant thereto, including a copy of the approved form
of Securities or coupons, if any, shall be certified by the Secretary or an
Assistant Secretary of the Company and delivered to the Trustee at or prior to
the delivery of the Company Order contemplated by Section 303 for the
authentication and delivery of such Securities.

         Unless otherwise specified as contemplated by Section 301, Bearer
Securities shall have interest coupons attached.

         The definitive Securities and coupons shall be printed, lithographed or
engraved or produced by any combination of these methods on a steel engraved
border or steel engraved borders or may be produced in any other manner, all as
determined by the officers of the Company executing such Securities or coupons,
as evidenced by their execution of such Securities or coupons.

         Securities distributed to holders of book-entry Preferred Securities
shall be distributed in the form of one or more global securities registered in
the name of a depositary or its nominee, and deposited with the Security
Registrar, as custodian for such depositary, or held by such depositary, for
credit by the depositary to the respective accounts of the beneficial owners of
the Securities represented thereby (or such other accounts as they may direct).
Securities distributed to holders of Preferred Securities other than book-entry
Preferred Securities shall not be issued in the form of a global security or any
other form intended to facilitate book-entry trading in beneficial interests in
such Securities.

SECTION 202.  Form of Trustee's Certificate of Authentication.

         Subject to Section 611, the Trustee's certificate of authentication
shall be in substantially the following form:

         This is one of the Securities of the series designated therein referred
to in the within-mentioned Indenture.

                        BANKERS TRUST COMPANY, AS TRUSTEE

                                              By:
                                                 ------------------------------
                                                         Authorized Officer

SECTION 203.  Securities Issuable in Global Form.

         If Securities of or within a series are issuable in global form, as
specified as contemplated by Section 301, then, notwithstanding clause (8) of
Section 301 and the provisions of Section 302, any such Security shall represent
such of the Outstanding Securities of such series as shall be specified therein
and may provide that it shall represent the aggregate amount of Outstanding
Securities of such series from time to time endorsed thereon and that the
aggregate amount of Outstanding Securities of such series represented thereby
may from time to time be increased or decreased to reflect exchanges. Any
endorsement of a Security in global form to reflect the amount, or any increase
or decrease in the amount, of Outstanding Securities represented thereby shall
be made by the Trustee in such manner and upon written instruction given by such
Person or Persons as shall be specified therein or in the Company Order to be
delivered to the Trustee pursuant to Section 303 or 304. Subject to the
provisions of Section 303 and, if applicable, Section 304, the Trustee shall
deliver and redeliver any Security in permanent global form in the manner and
upon written instructions given by the Person or Persons specified therein or in
the applicable Company Order. If a Company Order pursuant to Section 303 or 304
has been, or simultaneously is, delivered, any instructions by the Company with
respect to endorsement or delivery or redelivery of a


                                      -16-
<PAGE>   23
Security in global form shall be in writing but need not comply with Section 102
and need not be accompanied by an Opinion of Counsel.

         The provisions of the last sentence of Section 303 shall apply to any
Security represented by a Security in global form if such Security was never
issued and sold by the Company and the Company delivers to the Trustee the
Security in global form together with written instructions (which need not
comply with Section 102 and need not be accompanied by an Opinion of Counsel)
with regard to the reduction in the principal amount of Securities represented
thereby, together with the written statement contemplated by the last sentence
of Section 303.

         Notwithstanding the provisions of Section 307, unless otherwise
specified as contemplated by Section 301, payment of principal of and any
premium or Make-Whole Amount and interest on any Security in permanent global
form shall be made to the Person or Persons specified therein.

         Notwithstanding the provisions of Section 308 and except as provided in
the preceding paragraph, the Company, the Trustee and any agent of the Company
and the Trustee shall treat as the Holder of such principal amount of
Outstanding Securities represented by a permanent global Security (i) in the
case of a permanent global Security in registered form, the Holder of such
permanent global Security in registered form, or (ii) in the case of a permanent
global Security in bearer form, Euroclear or CEDEL.

                                  ARTICLE THREE
                                 THE SECURITIES

SECTION 301.  Amount Unlimited; Issuable in Series.

         The aggregate principal amount of Securities which may be authenticated
and delivered under this Indenture is unlimited.

         The Securities may be issued in one or more series. There shall be
established in or pursuant to one or more Board Resolutions, or indentures
supplemental hereto, prior to the issuance of Securities of any series, any or
all of the following, as applicable (each of which (except for the matters set
forth in clauses (1), (2) and (15) below), if so provided, may be determined
from time to time by the Company with respect to unissued Securities of or
within the series when issued from time to time):

         (1) the title of the Securities of or within the series (which shall
distinguish the Securities of such series from all other series of Securities);

         (2) any limit upon the aggregate principal amount of the Securities of
or within the series that may be authenticated and delivered under this
Indenture (except for Securities authenticated and delivered upon registration
of transfer of, or in exchange for, or in lieu of, other Securities of or within
the series pursuant to Section 304, 305, 306, 906, 1107, or 1305);

         (3) the date or dates, or the method by which such date or dates will
be determined, on which the principal of the Securities of or within the series
shall be payable and the amount of principal payable thereon;

         (4) the rate or rates (which may be fixed or variable) at which the
Securities of or within the series shall bear interest, if any, and Additional
Interest, if any, or the method by which such rate or rates shall be determined,
the date or dates from which such interest shall accrue or the method by which
such date or dates shall be determined, the Interest Payment Dates on which such
interest will be payable and the Regular Record Date, if any, for the interest
payable on any Registered Security on any Interest Payment Date, or the method
by which such date shall be determined, and the basis upon which interest shall
be calculated if other than that of a 360-day year consisting of twelve 30-day
months;

         (5) the place or places, if any, other than or in addition to the City
of Birmingham, Alabama or the Borough of Manhattan, The City of New York, where
the principal of (and premium or Make-Whole Amount, if any), interest, if any,
on, and Additional


                                      -17-
<PAGE>   24
Amounts, if any, payable in respect of, Securities of or within the series shall
be payable, any Registered Securities of or within the series may be surrendered
for registration of transfer, exchange or conversion and notices or demands to
or upon the Company in respect of the Securities of or within the series and
this Indenture may be served;

         (6) the period or periods within which, the price or prices (including
the premium or Make-Whole Amount, if any) at which, the currency or currencies,
currency unit or units or composite currency or currencies in which and other
terms and conditions upon which Securities of or within the series may be
redeemed in whole or in part, at the option of the Company, if the Company is to
have the option;

         (7) the obligation, if any, of the Company to redeem, repay or purchase
Securities of or within the series pursuant to any sinking fund or analogous
provision or at the option of a Holder thereof, and the period or periods within
which or the date or dates on which, the price or prices at which, the currency
or currencies, currency unit or units or composite currency or currencies in
which, and other terms and conditions upon which Securities of or within the
series shall be redeemed, repaid or purchased, in whole or in part, pursuant to
such obligation;

         (8) if other than denominations of $1,000 and any integral multiple
thereof, the denominations in which any Registered Securities of or within the
series shall be issuable and, if other than the denomination of $5,000 and any
integral multiple thereof, the denomination or denominations in which any Bearer
Securities of or within the series shall be issuable;

         (9)  if other than the Trustee, the identity of each Security Registrar
and/or Paying Agent;

         (10) if other than the principal amount thereof, the portion of the
principal amount of Securities of or within the series that shall be payable
upon declaration of acceleration of the maturity thereof pursuant to Section 502
or, if applicable, the portion of the principal amount of Securities of or
within the series that is convertible in accordance with the provisions of this
Indenture, or the method by which such portion shall be determined;

         (11) if other than Dollars, the Foreign Currency or Currencies in which
payment of the principal of (and premium or Make-Whole Amount, if any) or
interest or Additional Amounts, if any, on the Securities of or within the
series shall be payable or in which the Securities of or within the series shall
be denominated;

         (12) whether the amount of payments of principal of (and premium or
Make-Whole Amount, if any) or interest, if any, on the Securities of or within
the series may be determined with reference to an index, formula or other method
(which index, formula or method may be based, without limitation, on one or more
currencies, currency units, composite currencies, commodities, equity indices or
other indices), and the manner in which such amounts shall be determined;

         (13) whether the principal of (and premium or Make Whole Amount, if
any) or interest or Additional Amounts, if any, on the Securities of or within
the series are to be payable, at the election of the Company or a Holder
thereof, in a currency or currencies, currency unit or units or composite
currency or currencies other than that in which such Securities are denominated
or stated to be payable, the period or periods within which, and the terms and
conditions upon which, such election may be made, and the time and manner of,
and identity of the Exchange Rate Agent with responsibility for, determining the
exchange rate between the currency or currencies, currency unit or units or
composite currency or currencies in which such Securities are denominated or
stated to be payable and the currency or currencies, currency unit or units or
composite currency or currencies in which such Securities are to be so payable;

         (14) provisions, if any, granting special rights to the Holders of
Securities of or within the series upon the occurrence of such events as may be
specified;

         (15) (a) any deletions from, modifications of or additions to the
Events of Default with respect to Securities of or within the series, whether or
not such Events of Default are consistent with the Events of


                                      -18-
<PAGE>   25
Default set forth herein and (b) any deletions from, modifications of or
additions to the covenants of the Company with respect to the Securities of or
within the series, whether or not such covenants are consistent with the
covenants set forth herein;

         (16) whether Securities of or within the series are to be issuable as
Registered Securities, Bearer Securities (with or without coupons) or both, any
restrictions applicable to the offer, sale or delivery of Bearer Securities and
the terms upon which Bearer Securities of or within the series may be exchanged
for Registered Securities of or within the series and vice versa (if permitted
by applicable laws and regulations), whether any Securities of or within the
series are to be issuable initially in temporary global form and whether any
Securities of or within the series are to be issuable in permanent global form
(with or without coupons) and, if so, whether beneficial owners of interests in
any such permanent global Security may exchange such interests for Securities of
such series and of like tenor of any authorized form and denomination and the
circumstances under which any such exchanges may occur, if other than in the
manner provided in Section 305, and, if Registered Securities of or within the
series are to be issuable as a global Security, the identity of the depository
for such series;

         (17) the date as of which any Bearer Securities of or within the series
and any temporary global Security representing Outstanding Securities of or
within the series shall be dated if other than the date of original issuance of
the first Security of the series to be issued;

         (18) the Person to whom any interest on any Registered Security of the
series shall be payable, if other than the Person in whose name that Security
(or one or more Predecessor Securities) is registered at the close of business
on the Regular Record Date for such interest, the manner in which, or the Person
to whom, any interest on any Bearer Security of the series shall be payable, if
otherwise than upon presentation and surrender of the coupons appertaining
thereto as they severally mature, and the extent to which, or the manner in
which, any interest payable on a temporary global Security on an Interest
Payment Date will be paid if other than in the manner provided in Section 304;

         (19) the applicability, if any, of Sections 1402 and/or 1403 to the
Securities of or within the series and any provisions in modification of, in
addition to or in lieu of any of the provisions of Article Fourteen and, if the
Securities of the series are payable in a currency other than Dollars, whether,
for purposes of such defeasance or covenant defeasance the term "Government
Obligations" shall include obligations referred to in the definition of such
term which are not obligations of the United States or an agency or an
instrumentality thereof;

         (20) if the Securities of such series are to be issuable in definitive
form (whether upon original issue or upon exchange of a temporary Security of
such series) only upon receipt of certain certificates or other documents or
satisfaction of other conditions, then the form and/or terms of such
certificates, documents or conditions;

         (21) if the Securities of or within the series are to be issued upon
the exercise of debt warrants, the time, manner and place for such Securities to
be authenticated and delivered;

         (22) whether and under what circumstances the Company will pay
Additional Amounts as contemplated by Section 1011 on the Securities of or
within the series to any Holder who is not a United States person (including any
modification to the definition of such term) in respect of any tax, assessment
or governmental charge and, if so, whether the Company will have the option to
redeem such Securities rather than pay such Additional Amounts (and the terms of
any such option);

         (23) the obligation, if any, of the Company to permit the Securities of
such series to be converted into or exchanged for common stock of the Company or
other securities or property of the Company and the terms and conditions upon
which such conversion or exchange shall be effected (including, without
limitation, the initial conversion price or rate, the conversion or exchange
period, any adjustment of the applicable conversion or exchange price or rate
and any requirements relative to the reservation of such shares for purposes of
conversion or exchange);

                                      -19-

<PAGE>   26

         (24) if convertible or exchangeable, any applicable limitations on the
ownership or transferability of the securities or property into which such
Securities are convertible or exchangeable;

         (25) if such Securities are to be issued to a Regions Trust, the form
or forms of Trust Agreement and Regions Guarantee relating to the Securities of
such series;

         (26) if the principal amount payable at the Stated Maturity of any
Securities of the series will not be determinable as of any one or more dates
prior to the Stated Maturity, the amount which shall be deemed to be the
principal amount of such Securities as of any such date for any purpose
thereunder or hereunder, including the principal amount thereof which shall be
due and payable upon any Maturity other than the Stated Maturity or which shall
be deemed to be Outstanding as of any date prior to the Stated Maturity (or, in
any such case, the manner in which such amount deemed to be the principal amount
shall be determined); and

         (27) any other terms of the series (which terms shall not be
inconsistent with the provisions of this Indenture except as permitted by
Section 901(5).

         All Securities of any one series and the coupons appertaining to any
Bearer Securities of such series, if any, shall be substantially identical
except, in the case of Registered or Bearer Securities issued in global form, as
to denomination and except as may otherwise be provided in or pursuant to such
Board Resolution or in any indenture supplemental hereto. All Securities of any
one series need not be issued at the same time and, unless otherwise provided, a
series may be reopened, without the consent of the Holders, for issuances of
additional Securities of such series.

         If any of the terms of the Securities of any series are established by
action taken pursuant to one or more Board Resolutions, a copy of an appropriate
record of such action(s) shall be certified by the Secretary or an Assistant
Secretary of the Company and delivered to the Trustee at or prior to the
delivery of the Company Order for authentication and delivery of such
Securities.

         The Securities shall be subordinated in right of payment to Senior
Debt, as provided in Article Seventeen.

SECTION 302.  Denominations.

         The Securities of each series shall be issuable in such denominations
as shall be specified as contemplated by Section 301. With respect to Securities
of any series denominated in Dollars, in the absence of any such provisions with
respect to the Securities of any series, the Registered Securities of such
series, other than Registered Securities issued in global form (which may be of
any denomination), shall be issuable in denominations of $1,000 and any integral
multiple thereof and the Bearer Securities of such series other than Bearer
Securities issued in global form (which may be of any denomination), shall be
issuable in denominations of $5,000.

SECTION 303.  Execution, Authentication, Delivery and Dating.

         The Securities and any coupons appertaining thereto shall be executed
on behalf of the Company by its President or a Vice President, under its
corporate seal reproduced thereon, and attested by its Secretary or an Assistant
Secretary. The signature of any of these officers on the Securities and coupons
may be manual or facsimile signatures of the present or any future such
authorized officer and may be imprinted or otherwise reproduced on the
Securities.

         Securities or coupons appertaining thereto 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 Securities or did not hold such offices at the date of such
Securities or coupons.


                                      -20-
<PAGE>   27
         At any time and from time to time after the execution and delivery of
this Indenture, the Company may deliver Securities of any series, together with
any coupon appertaining thereto, executed by the Company to the Trustee for
authentication, together with a Company Order for the authentication and
delivery of such Securities, and the Trustee in accordance with the Company
Order shall authenticate and deliver such Securities; provided, however, that,
in connection with its original issuance, no Bearer Security shall be mailed or
otherwise delivered to any location in the United States; and provided further
that, unless otherwise specified with respect to any series of Securities
pursuant to Section 301 a Bearer Security may be delivered in connection with
its original issuance only if the Person entitled to receive such Bearer
Security shall have furnished a certificate to Euroclear or CEDEL, as the case
may be, in the form set forth in Exhibit A-1 to this Indenture or such other
certificate as may be specified with respect to any series of Securities
pursuant to Section 301, dated no earlier than 15 days prior to the earlier of
the date on which such Bearer Security is delivered and the date on which any
temporary Security first becomes exchangeable for such Bearer Security in
accordance with the terms of such temporary Security and this Indenture. Except
as permitted by Section 306, the Trustee shall not authenticate and deliver any
Bearer Security unless all appurtenant coupons for interest then matured have
been detached and canceled.

         If all of the Securities are not to be issued at one time and if the
Board Resolution or supplemental indenture establishing such series shall so
permit, such Company Order may set forth procedures acceptable to the Trustee
for the issuance of such Securities and determining the terms of particular
Securities of such series, such as interest rate or formula, maturity date, date
of issuance and date from which interest shall accrue. In authenticating
Securities, and accepting the additional responsibilities under this Indenture
in relation to such Securities, the Trustee shall be entitled to receive, and
(subject to Section 612 and TIA Section 315(a) through 315(d)) shall be fully
protected in conclusively relying upon:

         (i)  an Opinion of Counsel complying with Section 102 and stating that:

                  (a) the form or forms of such Securities and any coupons have
been, or will have been upon compliance with such procedures as may be specified
therein, established in conformity with the provisions of this Indenture;

                  (b) the terms of such Securities and any coupons have been, or
will have been upon compliance with such procedures as may be specified therein,
established in conformity with the provisions of this Indenture; and

                  (c) such Securities, together with any coupons appertaining
thereto, when completed pursuant to such procedures as may be specified therein,
and executed and delivered by the Company to the Trustee for authentication in
accordance with this Indenture, authenticated and delivered by the Trustee in
accordance with this Indenture and issued by the Company in the manner and
subject to any conditions specified in such Opinion of Counsel, will constitute
legal, valid and binding obligations of the Company, enforceable in accordance
with their terms, subject to applicable bankruptcy, insolvency, reorganization
and other similar laws of general applicability relating to or affecting the
enforcement of creditors' rights generally and to general equitable principles
and to such other matters as may be specified therein; and

         (ii) an Officers' Certificate complying with Section 102 and stating
that all conditions precedent provided for in this Indenture relating to the
issuance of such Securities have been, or will have been upon compliance with
such procedures as may be specified therein, complied with and that, to the best
of the knowledge of the signers of such certificate, no Event of Default with
respect to such Securities shall have occurred and be continuing.

         Notwithstanding the provisions of Section 301 and of the preceding
paragraph, if all the Securities of any series are not to be issued at one time,
it shall not be necessary to deliver a Company Order, an Opinion of Counsel or
an Officers' Certificate otherwise required pursuant to the preceding paragraph
at the time of issuance of each Security of such series, but such order, opinion
and certificate, with appropriate modifications to cover such future issuances,
shall be delivered at or before the time of issuance of the first Security of
such series.


                                      -21-
<PAGE>   28
         The Trustee shall not be required to authenticate such Securities if
the issue of such Securities pursuant to this Indenture will affect the
Trustee's own rights, duties, obligations or immunities under the Securities and
this Indenture or otherwise in a manner which is not reasonably acceptable to
the Trustee.

         Each Registered Security shall be dated the date of its authentication
and each Bearer Security shall be dated as of the date specified as contemplated
by Section 301.

         No Security or coupon appertaining thereto shall be entitled to any
benefit under this Indenture or be valid or obligatory for any purpose unless
there appears on such Security or the Security to which such coupon appertains a
certificate of authentication substantially in the form provided for herein duly
executed by the Trustee by manual signature of an authorized officer, and such
certificate upon any Security shall be conclusive evidence, and the only
evidence, that such Security has been duly authenticated and delivered hereunder
and is entitled to the benefits of this Indenture. Notwithstanding the
foregoing, if any Security shall have been authenticated and delivered hereunder
but never issued and sold by the Company, and the Company shall deliver such
Security to the Trustee for cancellation as provided in Section 309 together
with a written statement (which need not comply with Section 102 and need not be
accompanied by an Opinion of Counsel) stating that such Security has never been
issued or sold by the Company, for all purposes of this Indenture such Security
shall be deemed never to have been authenticated and delivered hereunder and
shall never be entitled to the benefits of this Indenture.

SECTION 304.  Temporary Securities.

         (a) Pending the preparation of definitive Securities of any series, the
Company may execute, and upon Company Order the Trustee shall authenticate and
deliver, temporary Securities which are printed, lithographed, typewritten,
mimeographed or otherwise produced, in any authorized denomination,
substantially of the tenor of the definitive Securities in lieu of which they
are issued, in registered form, or, if authorized, in bearer form with one or
more coupons or without coupons, and with such appropriate insertions,
omissions, substitutions and other variations as the officers of the Company
executing such Securities may determine, as conclusively evidenced by their
execution of such Securities. In the case of Securities of any series, such
temporary Securities may be in global form.

         Except in the case of temporary Securities in global form (which shall
be exchanged in accordance with Section 304(b) or as otherwise provided in or
pursuant to a Board Resolution), if temporary Securities of any series are
issued, the Company will cause definitive Securities of that series to be
prepared without unreasonable delay. After the preparation of definitive
Securities of such series, the temporary Securities of such series shall be
exchangeable for definitive Securities of such series upon surrender of the
temporary Securities of such series at the office or agency of the Company in a
Place of Payment for that series, without charge to the Holder. Upon surrender
for cancellation of any one or more temporary Securities of any series
(accompanied by any non-matured coupons appertaining thereto), the Company shall
execute and the Trustee shall authenticate and deliver in exchange therefor a
like principal amount of definitive Securities of the same series of authorized
denominations; provided, however, that no definitive Bearer Security shall be
delivered in exchange for a temporary

         Registered Security; and provided further that a definitive Bearer
Security shall be delivered in exchange for a temporary Bearer Security only in
compliance with the conditions set forth in Section 303. Until so exchanged, the
temporary Securities of any series shall in all respects be entitled to the same
benefits under this Indenture as definitive Securities of such series.

         (b) Unless otherwise provided as contemplated in Section 301, this
Section 304(b) shall govern the exchange of temporary Securities issued in
global form other than through the facilities of DTC. If any such temporary
Security is issued in global form, then such temporary global Security shall,
unless otherwise provided therein, be delivered to the London office of a
depository or common depository (the "Common Depository"), for the benefit of
Euroclear and CEDEL.

         Without unnecessary delay but in any event not later than the date
specified in, or determined pursuant to the terms of, any such temporary global
Security (the "Exchange Date"), the Company shall


                                      -22-
<PAGE>   29
deliver to the Trustee definitive Securities, in an aggregate principal amount
equal to the principal amount of such temporary global Security, executed by the
Company. On or after the Exchange Date, such temporary global Security shall be
surrendered by the Common Depository to the Trustee, as the Company's agent for
such purpose, to be exchanged, in whole or from time to time in part, for
definitive Securities without charge, and the Trustee shall authenticate and
deliver, in exchange for each portion of such temporary global Security, an
equal aggregate principal amount of definitive Securities of or within the same
series of authorized denominations and of like tenor as the portion of such
temporary global Security to be exchanged. The definitive Securities to be
delivered in exchange for any such temporary global Security shall be in bearer
form, registered form, permanent global bearer form or permanent global
registered form, or any combination thereof, as specified as contemplated by
Section 301, and, if any combination thereof is so specified, as requested by
the beneficial owner thereof; provided, however, that, unless otherwise
specified in such temporary global Security, upon such presentation by the
Common Depository, such temporary global Security is accompanied by a
certificate dated the Exchange Date or a subsequent date and signed by Euroclear
as to the portion of such temporary global Security, if any, held for its
account then to be exchanged and a certificate dated the Exchange Date or a
subsequent date and signed by CEDEL as to the portion of such temporary global
Security, if any, held for its account then to be exchanged, each in the form
set forth in Exhibit A-2 to this Indenture or in such other form as may be
established pursuant to Section 301; and provided further that definitive Bearer
Securities shall be delivered in exchange for a portion of a temporary global
Security only in compliance with the requirements of Section 303.

         Unless otherwise specified in such temporary global Security, the
interest of a beneficial owner of Securities of a series in a temporary global
Security shall be exchanged for definitive Securities of the same series and of
like tenor following the Exchange Date when the account holder instructs
Euroclear or CEDEL, as the case may be, to request such exchange on his behalf
and delivers to Euroclear or CEDEL, as the case may be, a certificate in the
form set forth in Exhibit A-1 to this Indenture (or in such other form as may be
established pursuant to Section 301), dated no earlier than 15 days prior to the
Exchange Date, copies of which certificate shall be available from the offices
of Euroclear or CEDEL, the Trustee, any Authenticating Agent appointed for such
series of Securities and each Paying Agent. Unless otherwise specified in such
temporary global Security, any such exchange shall be made free of charge to the
beneficial owners of such temporary global Security, except that a Person
receiving definitive Securities must bear the cost of insurance, postage,
transportation and the like unless such Person takes delivery of such definitive
Securities in person at the offices of Euroclear or CEDEL. Definitive Securities
in bearer form to be delivered in exchange for any portion of a temporary global
Security shall be delivered only outside the United States.

         Until exchanged in full as hereinabove provided, the temporary
Securities of any series shall in all respects be entitled to the same benefits
under this Indenture as definitive Securities of the same series and of like
tenor authenticated and delivered hereunder, except that, unless otherwise
specified as contemplated by Section 301, interest payable on a temporary global
Security on an Interest Payment Date for Securities of such series occurring
prior to the applicable Exchange Date shall be payable to Euroclear or CEDEL on
such Interest Payment Date upon delivery by Euroclear or CEDEL to the Trustee of
a certificate or certificates in the form set forth in Exhibit A-2 to this
Indenture (or in such other forms as may be established pursuant to Section
301), for credit without further interest on or after such Interest Payment Date
to the respective accounts of Persons who are the beneficial owners of such
temporary global Security on such Interest Payment Date and who have each
delivered to Euroclear or CEDEL, as the case may be, a certificate dated no
earlier than 15 days prior to the Interest Payment Date occurring prior to such
Exchange Date in the form set forth as Exhibit A-1 to this Indenture (or in such
other forms as may be established pursuant to Section 301). Notwithstanding
anything to the contrary herein contained, the certifications made pursuant to
this paragraph shall satisfy the certification requirements of the preceding two
paragraphs of this Section 304(b) and of the third paragraph of Section 303 of
this Indenture and the interests of the Persons who are the beneficial owners of
the temporary global Security with respect to which such certification was made
will be exchanged for definitive Securities of the same series and of like tenor
on the Exchange Date or the date of certification if such date occurs after the
Exchange Date, without further act or deed by such beneficial owners. Except as
otherwise provided in this paragraph, no payments of principal or interest owing
with respect to a beneficial interest in a temporary global Security will be
made


                                      -23-
<PAGE>   30
unless and until such interest in such temporary global Security shall have been
exchanged for an interest in a definitive Security. Any interest so received by
Euroclear or CEDEL and not paid as herein provided shall be returned to the
Trustee prior to the expiration of two years after such Interest Payment Date in
order to be repaid to the Company.

SECTION 305.  Registration, Registration of Transfer and Exchange.

         The Company shall cause to be kept at the Corporate Trust Office of the
Trustee or in any office or agency of the Company in a Place of Payment a
register for each series of Securities (the registers maintained in such office
or in any such office or agency of the Company in a Place of Payment being
herein sometimes referred to collectively as the "Security Register") in which,
subject to such reasonable regulations as it or the Security Registrar may
prescribe, the Company shall provide for the registration of Registered
Securities and of transfers of Registered Securities. The Security Register
shall be in written form or any other form capable of being converted into
written form within a reasonable time. The Trustee, at its Corporate Trust
Office, is hereby initially appointed "Security Registrar" for the purpose of
registering Registered Securities and transfers of Registered Securities on such
Security Register as herein provided. In the event that the Trustee shall cease
to be Security Registrar, it shall have the right to examine the Security
Register at all reasonable times and to require that a copy of the Security
Register in written form be delivered to it from time to time as reasonably
requested. Subject to the provisions of this Section 305, upon surrender for
registration of transfer of any Registered Security of any series at any office
or agency of the Company in a Place of Payment for that series, the Company
shall execute, and the Trustee shall authenticate and deliver, in the name of
the designated transferee or transferees, one or more new Registered Securities
of the same series, of any authorized denominations and of a like aggregate
principal amount, bearing a number not contemporaneously outstanding, and
containing identical terms and provisions.

         Subject to the provisions of this Section 305, at the option of the
Holder, Registered Securities of any series (not in global form) may be
exchanged for other Registered Securities of the same series, of any authorized
denomination or denominations and of a like aggregate principal amount,
containing identical terms and provisions, upon surrender of the Registered
Securities to be exchanged at any such office or agency. Whenever any such
Registered Securities are so surrendered for exchange, the Company shall
execute, and the Trustee shall authenticate and deliver, the Registered
Securities which the Holder making the exchange is entitled to receive. Unless
otherwise specified with respect to any series of Securities as contemplated by
Section 301, Bearer Securities may not be issued in exchange for Registered
Securities.

         If (but only if) permitted as contemplated by Section 301, at the
option of the Holder, Bearer Securities of any series may be exchanged for
Registered Securities of the same series of any authorized denominations and of
a like aggregate principal amount and tenor, upon surrender of the Bearer
Securities to be exchanged at any such office or agency, with all unmatured
coupons and all matured coupons in default thereto appertaining. If the Holder
of a Bearer Security is unable to produce any such unmatured coupon or coupons
or matured coupon or coupons in default, any such permitted exchange may be
effected if the Bearer Securities are accompanied by payment in funds acceptable
to the Company in an amount equal to the face amount of such missing coupon or
coupons, or the surrender of such missing coupon or coupons may be waived by the
Company and the Trustee if there is furnished to them such security or indemnity
as they may require to save each of them and any Paying Agent harmless. If
thereafter the Holder of such Security shall surrender to any Paying Agent any
such missing coupon in respect of which such a payment shall have been made,
such Holder shall be entitled to receive the amount of such payment; provided,
however, that, except as otherwise provided in Section 1002, interest
represented by coupons shall be payable only upon presentation and surrender of
those coupons at an office or agency located outside the United States.
Notwithstanding the foregoing, in case a Bearer Security of any series is
surrendered at any such office or agency in a permitted exchange for a
Registered Security of the same series and like tenor after the close of
business at such office or agency on (i) any Regular Record Date and before the
opening of business at such office or agency on the relevant Interest Payment
Date, or (ii) any


                                      -24-
<PAGE>   31
Special Record Date and before the opening of business at such office or agency
on the related proposed date for payment of Defaulted Interest, such Bearer
Security shall be surrendered without the coupon relating to such Interest
Payment Date or proposed date for payment, as the case may be, and interest or
Defaulted Interest, as the case may be, will not be payable on such Interest
Payment Date or proposed date for payment, as the case may be, in respect of the
Registered Security issued in exchange for such Bearer Security, but will be
payable only to the Holder of such coupon when due in accordance with the
provisions of this Indenture. Whenever any Securities are so surrendered for
exchange, the Company shall execute, and the Trustee shall authenticate and
deliver, the Securities which the holder making the exchange is entitled to
receive.

         Notwithstanding the foregoing, except as otherwise specified as
contemplated by Section 301, any permanent global Security shall be exchangeable
only as provided in this paragraph. If the depository for any permanent global
Security is DTC, then, unless the terms of such global Security expressly permit
such global Security to be exchanged in whole or in part for definitive
Securities, a global Security may be transferred, in whole but not in part, only
to a nominee of DTC, or by a nominee of DTC to DTC, or to a successor to DTC for
such global Security selected or approved by the Company or to a nominee of such
successor to DTC. If at any time DTC notifies the Company that it is unwilling
or unable to continue as depository for the applicable global Security or
Securities or if at any time DTC ceases to be a clearing agency registered under
the Exchange Act if so required by applicable law or regulation, the Company
shall appoint a successor depository with respect to such global Security or
Securities. If (x) a successor depository for such global Security or Securities
is not appointed by the Company within 90 days after the Company receives such
notice or becomes aware of such unwillingness, inability or ineligibility, (y)
an Event of Default has occurred and is continuing and the beneficial owners
representing a majority in principal amount of the applicable series of
Securities represented by such global Security or Securities advise DTC to cease
acting as depository for such global Security or Securities or (z) the Company,
in its sole discretion, determines at any time that all Outstanding Securities
(but not less than all) of any series issued or issuable in the form of one or
more global Securities shall no longer be represented by such global Security or
Securities (provided, however, the Company may not make such determination
during the 40-day restricted period provided by Regulation S under the
Securities Act or during any other similar period during which the Securities
must be held in global form as may be required by the Securities Act), then the
Company shall execute, and the Trustee shall authenticate and deliver definitive
Securities of like series, rank, tenor and terms in definitive form in an
aggregate principal amount equal to the principal amount of such global Security
or Securities. If any beneficial owner of an interest in a permanent global
Security is otherwise entitled to exchange such an interest for Securities of
such series and of like tenor and principal amount of another authorized form
and denomination, as specified as contemplated by Section 301 and provided that
any applicable notice provided in the permanent global Security shall have been
given, then without unnecessary delay but in any event not later than the
earliest date on which such interest may be so exchanged, the Company shall
execute, and the Trustee shall authenticate and deliver definitive Securities in
aggregate principal amount equal to the principal amount of such beneficial
owner's interest in such permanent global Security. On or after the earliest
date on which such interests may be so exchanged, such permanent global Security
shall be surrendered for exchange by DTC or such other depository as shall be
specified in the Company Order with respect thereto to the Trustee, as the
Company's agent for such purpose; provided, however, that no such exchanges may
occur during a period beginning at the opening of business 15 days before any
selection of Securities to be redeemed and ending on the relevant Redemption
Date if the Security for which exchange is requested may be among those selected
for redemption; and provided further that no Bearer Security delivered in
exchange for a portion of a permanent global Security shall be mailed or
otherwise delivered to any location in the United States. If a Registered
Security is issued in exchange for any portion of a permanent global Security
after the close of business at the office or agency where such exchange occurs
on (i) any Regular Record Date and before the opening of business at such office
or agency on the relevant Interest Payment Date, or (ii) any Special Record Date
and before the opening of business at such office or agency on the related
proposed date for payment of Defaulted Interest, interest or Defaulted Interest,
as the case may be, will not be payable on such Interest Payment Date or
proposed date for payment, as the case may be, in respect of such Registered
Security, but will be payable on such Interest Payment Date or proposed date for
payment, as the case may be, only to the Person to whom interest in respect of
such portion of such permanent global Security is payable in accordance with the
provisions of this Indenture.


                                      -25-
<PAGE>   32
         All Securities issued upon any registration of transfer or exchange of
Securities shall be the valid obligations of the Company, evidencing the same
debt, and entitled to the same benefits under this Indenture, as the Securities
surrendered upon such registration of transfer or exchange.

         Every Registered Security presented or surrendered for registration of
transfer or for exchange or redemption shall (if so required by the Company, the
Trustee or the Security Registrar) be duly endorsed, or be accompanied by a
written instrument of transfer in form satisfactory to the Security Registrar,
duly executed by the Holder thereof or his attorney duly authorized in writing.

         No service charge shall be made for any registration of transfer or
exchange of Securities, 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 or exchange of Securities, other than
exchanges pursuant to Section 304, 906, 1107 or 1305 not involving any transfer.

         The Company or the Trustee, as applicable, shall not be required (i) to
issue, register the transfer of or exchange any Security if such Security may be
among those selected for redemption during a period beginning at the opening of
business 15 days before selection of the Securities to be redeemed under Section
1103 and ending at the close of business on (A) if such Securities are issuable
only as Registered Securities, the day of the mailing of the relevant notice of
redemption and (B) if such Securities are issuable as Bearer Securities, the day
of the first publication of the relevant notice of redemption or, if such
Securities are also issuable as Registered Securities and there is no
publication, the mailing of the relevant notice of redemption, or (ii) to
register the transfer of or exchange any Registered Security so selected for
redemption in whole or in part, except, in the case of any Registered Security
to be redeemed in part, the portion thereof not to be redeemed, or (iii) to
exchange any Bearer Security so selected for redemption except that such a
Bearer Security may be exchanged for a Registered Security of that series and
like tenor, provided that such Registered Security shall be simultaneously
surrendered for redemption, or (iv) to issue or to register the transfer or
exchange of any Security which has been surrendered for repayment at the option
of the Holder, except the portion, if any, of such Security not to be so repaid.

SECTION 306.  Mutilated, Destroyed, Lost and Stolen Securities.

         If any mutilated Security or a Security with a mutilated coupon
appertaining to it is surrendered to the Trustee or the Company, together with
such security or indemnity as may be required by the Company or the Trustee to
save each of them or any agent of either of them harmless, the Company shall
execute and the Trustee shall authenticate and deliver in exchange therefor a
new Security of the same series and principal amount, containing identical terms
and provisions and bearing a number not contemporaneously outstanding, with
coupons corresponding to the coupons, if any, appertaining to the surrendered
Security.

         If there shall be delivered to the Company and to the Trustee (i)
evidence to their satisfaction of the destruction, loss or theft of any Security
or coupon, and (ii) such security or indemnity as may be required by them to
save each of them and any agent of either of them harmless, then, in the absence
of actual notice to the Company or the Trustee that such Security or coupon has
been acquired by a bona fide purchaser, the Company shall execute and upon its
written request the Trustee shall authenticate and deliver, in lieu of any such
destroyed, lost or stolen Security or in exchange for the Security to which a
destroyed, lost or stolen coupon appertains (with all appurtenant coupons not
destroyed, lost or stolen), a new Security of the same series and principal
amount, containing identical terms and provisions and bearing a number not
contemporaneously outstanding, with coupons corresponding to the coupons, if
any, appertaining to such destroyed, lost or stolen Security or to the Security
to which such destroyed, lost or stolen coupon appertains.

         Notwithstanding the provisions of the previous two paragraphs, in case
any such mutilated, destroyed, lost or stolen Security or coupon has become or
is about to become due and payable, the Company in its discretion may, instead
of issuing a new Security, with coupons corresponding to coupons, if any,
appertaining to such destroyed, lost or stolen Security or to the Security to
which such destroyed, lost or stolen coupon appertains, pay such Security or
coupon; provided, however, that payment of


                                      -26-
<PAGE>   33
principal of (and premium or Make- Whole Amount, if any), any interest on and
any Additional Amounts with respect to Bearer Securities shall, except as
otherwise provided in Section 1002, be payable only at an office or agency
located outside the United States and, unless otherwise specified as
contemplated by Section 301, any interest on Bearer Securities shall be payable
only upon presentation and surrender of the coupons appertaining thereto.

         Upon the issuance of any new Security under this Section, the Company
may require the payment of a sum sufficient to cover any tax or other
governmental charge that may be imposed in relation thereto and any other
expenses (including the fees and expenses of the Trustee) connected therewith.

         Every new Security of any series with its coupons, if any, issued
pursuant to this Section in lieu of any destroyed, lost or stolen Security, or
in exchange for a Security to which a destroyed, lost or stolen coupon
appertains, shall constitute an original additional contractual obligation of
the Company, whether or not the destroyed, lost or stolen Security and its
coupons, if any, or the destroyed, lost or stolen coupon shall be at any time
enforceable by anyone, and shall be entitled to all the benefits of this
Indenture equally and proportionately with any and all other Securities of that
series and their coupons, if any, duly issued hereunder.

         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 Securities or coupons.

SECTION 307.  Payment of Interest; Interest Rights Preserved.

         Except as otherwise specified with respect to a series of Securities in
accordance with the provisions of Section 301, interest on any Registered
Security that is payable, and is punctually paid or duly provided for, on any
Interest Payment Date shall be paid to the Person in whose name that Security
(or one or more Predecessor Securities) is registered at the close of business
on the Regular Record Date for such interest at the office or agency of the
Company maintained for such purpose pursuant to Section 1002; provided, however,
that each installment of interest on any Registered Security may at the
Company's option be paid by (i) mailing a check for such interest, payable to or
upon the written order of the Person entitled thereto pursuant to Section 308,
to the address of such Person as it appears on the Security Register or (ii)
transfer to an account maintained by the payee located inside the United States.

         Unless otherwise provided as contemplated by Section 301 with respect
to the Securities of any series, payment of interest may be made, in the case of
a Bearer Security, by transfer to an account maintained by the payee with a bank
located outside the United States.

         Unless otherwise provided as contemplated by Section 301, every
permanent global Security will provide that interest, if any, payable on any
Interest Payment Date will be paid to DTC, Euroclear and/or CEDEL, as the case
may be, with respect to that portion of such permanent global Security held for
its account by DTC, Euroclear or CEDEL, as the case may be, for the purpose of
permitting such party to credit the interest received by it in respect of such
permanent global Security to the accounts of the beneficial owners thereof.

         In case a Bearer Security of any series is surrendered in exchange for
a Registered Security of such series after the close of business (at an office
or agency in a Place of Payment for such series) on any Regular Record Date and
before the opening of business (at such office or agency) on the next succeeding
Interest Payment Date, such Bearer Security shall be surrendered without the
coupon relating to such Interest Payment Date and interest will not be payable
on such Interest Payment Date in respect of the Registered Security issued in
exchange for such Bearer Security, but will be payable only to the Holder of
such coupon when due in accordance with the provisions of this Indenture.

         Except as otherwise specified with respect to a series of Securities in
accordance with the provisions of section 301, any interest on any Registered
Security of any series that is payable, but is not punctually paid or duly
provided for, on any Interest Payment Date (herein called "Defaulted Interest")


                                      -27-
<PAGE>   34
shall forthwith cease to be payable to the registered Holder thereof on the
relevant Regular Record Date by virtue of having been such Holder, and such
Defaulted Interest may be paid by the Company, at its election in each case, as
provided in clause (1) or (2) below:

         (1) The Company may elect to make payment of any Defaulted Interest to
the Persons in whose names the Registered Securities of such series (or their
respective Predecessor Securities) are registered at the close of business on a
Special Record Date for the payment of such Defaulted Interest, which shall be
fixed in the following manner. The Company shall notify the Trustee in writing
of the amount of Defaulted Interest proposed to be paid on each Registered
Security of such series and the date of the proposed payment (which shall not be
less than 20 days after such notice is received by the Trustee), and at the same
time the Company shall deposit with the Trustee an amount of money in the
currency or currencies, currency unit or units or composite currency or
currencies in which the Securities of such series are payable (except as
otherwise specified pursuant to Section 301 for the Securities of such series)
equal to the aggregate amount proposed to be paid in respect of such Defaulted
Interest or shall make arrangements satisfactory to the Trustee for such deposit
on or prior to the date of the proposed payment, such money when deposited to be
held in trust for the benefit of the Persons entitled to such Defaulted Interest
as in this clause provided. Thereupon the Trustee shall fix a Special Record
Date for the payment of such Defaulted Interest which shall be not more than 15
days and not less than 10 days prior to the date of the proposed payment and not
less than 10 days after the receipt by the Trustee of the notice of the proposed
payment. The Trustee shall promptly notify the Company of such Special Record
Date and, in the name and at the expense of the Company, shall cause notice of
the proposed payment of such Defaulted Interest and the Special Record Date
therefor to be mailed, first-class postage prepaid, to each Holder of Registered
Securities of such series at his address as it appears in the Security Register
not less than 10 days prior to such Special Record Date. Notice of the proposed
payment of such Defaulted Interest and the Special Record Date therefor having
been mailed as aforesaid, such Defaulted Interest shall be paid to the Persons
in whose names the Registered Securities of such series (or their respective
Predecessor Securities) are registered at the close of business on such Special
Record Date and shall no longer be payable pursuant to the following clause (2).
In case a Bearer Security of any series is surrendered at the office or agency
in a Place of Payment for such series in exchange for a Registered Security of
such series after the close of business at such office or agency on any Special
Record Date and before the opening of business at such office or agency on the
related proposed date for payment of Defaulted Interest, such Bearer Security
shall be surrendered without the coupon relating to such proposed date of
payment and Defaulted Interest will not be payable on such proposed date of
payment in respect of the Registered Security issued in exchange for such Bearer
Security, but will be payable only to the Holder of such coupon when due in
accordance with the provisions of this Indenture.

         (2) The Company may make payment of any Defaulted Interest on the
Registered Securities of any series in any other lawful manner not inconsistent
with the requirements of any securities exchange on which such Securities may be
listed, and upon such notice as may be required by such exchange, if, after
written notice given by the Company to the Trustee of the proposed payment
pursuant to this clause, such manner of payment shall be deemed practicable by
the Trustee.

         Subject to the foregoing provisions of this Section and Section 305,
each Security delivered under this Indenture upon registration of transfer of or
in exchange for or in lieu of any other Security shall carry the rights to
interest accrued and unpaid, and to accrue, which were carried by such other
Security.

         Subject to the provisions of Section 1402 and except as otherwise
specified with respect to a series of Securities in accordance with the
provisions of section 301, in the case of any Security which is converted or
exchanged after any Regular Record Date and on or prior to the next succeeding
Interest Payment Date (other than any Security, the principal of (or premium, if
any, on) which shall become due and payable, whether at a Stated Maturity or by
declaration of acceleration, call for redemption, or otherwise, prior to such
Interest Payment Date), interest whose Stated Maturity is on such Interest
Payment Date shall be payable on such Interest Payment Date notwithstanding such
conversion or exchange, and such interest (whether or not punctually paid or
duly provided for) shall be paid to the Person in whose name that Security (or
one or more Predecessor Securities) is registered at the close of business on
such Regular Record Date. Except as otherwise expressly provided in the
immediately preceding sentence, in the



                                      -28-
<PAGE>   35
case of any Security which is converted or exchanged, interest whose Stated
Maturity is after the date of conversion or exchange of such Security shall not
be payable.

SECTION 308.  Persons Deemed Owners.

         Prior to due presentment of a Registered Security for registration of
transfer, the Company, the Trustee and any agent of the Company or the Trustee
may treat the Person in whose name such Registered Security is registered as the
owner of such Security for the purpose of receiving payment of principal of (and
premium or Make-Whole Amount, if any), and (subject to Sections 305 and 307)
interest on and Additional Amounts with respect to, such Registered Security and
for all other purposes whatsoever, whether or not such Registered Security be
overdue, and neither the Company, the Trustee nor any agent of the Company or
the Trustee shall be affected by notice to the contrary.

         Title to any Bearer Security and any coupons appertaining thereto shall
pass by delivery. The Company, the Trustee and any agent of the Company or the
Trustee may treat the Holder of any Bearer Security and the Holder of any coupon
as the absolute owner of such Security or coupon for the purpose of receiving
payment thereof or on account thereof and for all other purposes whatsoever,
whether or not such Security or coupon be overdue, and neither the Company, the
Trustee nor any agent of the Company or the Trustee shall be affected by notice
to the contrary.

         None of the Company, the Trustee, any Paying Agent or the Security
Registrar will have any responsibility or liability for any aspect of the
records relating to or payments made on account of beneficial ownership
interests of a Security in global form or for maintaining, supervising or
reviewing any records relating to such beneficial ownership interests.

         Notwithstanding the foregoing, with respect to any global Security,
nothing herein shall prevent the Company, the Trustee, or any agent of the
Company or the Trustee, from giving effect to any written certification, proxy
or other authorization furnished by any depository, as a Holder, with respect to
such global Security or impair, as between such depository and owners of
beneficial interests in such global Security, the operation of customary
practices governing the exercise of the rights of such depository (or its
nominee) as Holder of such global Security.

SECTION 309.  Cancellation.

         All Securities and coupons surrendered for payment, redemption,
repayment at the option of the Holder, registration of transfer or exchange or
for credit against any sinking fund payment shall, if surrendered to any Person
other than the Trustee, be delivered to the Trustee, and any such Securities and
coupons and Securities and coupons surrendered directly to the Trustee for any
such purpose shall be promptly canceled by it. The Company may at any time
deliver to the Trustee for cancellation any Securities previously authenticated
and delivered hereunder which the Company may have acquired in any manner
whatsoever, and may deliver to the Trustee (or to any other Person for delivery
to the Trustee) for cancellation any Securities previously authenticated
hereunder which the Company has not issued and sold, and all Securities so
delivered shall be promptly canceled by the Trustee. If the Company shall so
acquire any of the Securities, however, such acquisition shall not operate as a
redemption or satisfaction of the indebtedness represented by such Securities
unless and until the same are surrendered to the Trustee for cancellation. No
Securities shall be authenticated in lieu of or in exchange for any Securities
canceled as provided in this Section, except as expressly permitted by this
Indenture. Canceled Securities and coupons held by the Trustee shall be
destroyed by the Trustee and, if required in writing by the Company, the Trustee
shall deliver a certificate of such destruction to the Company, unless by a
Company Order the Company directs their return to it.

SECTION 310.  Computation of Interest.

         Except as otherwise specified as contemplated by Section 301 with
respect to Securities of any series, interest on the Securities of each series
shall be computed on the basis of a 360-day year consisting of twelve 30-day
months.


                                      -29-
<PAGE>   36

SECTION 311.  Deferrals of Interest Payment Dates.

         If specified as contemplated by Section 201 or Section 301 with respect
to the Securities of a particular series, so long as no Event of Default has
occurred and is continuing, the Company shall have the right, at any time during
the term of such series, from time to time to defer the payment of interest on
such Securities for such period or periods as may be specified as contemplated
by Section 301 (each, an "Extension Period") during which Extension Periods the
Company shall have the right to make partial payments of interest on any
Interest Payment Date. No Extension Period shall end on a date other than an
Interest Payment Date. At the end of any such Extension Period the Company shall
pay all interest then accrued and unpaid on the Securities (together with
Additional Interest thereon, if any, at the rate specified for the Securities of
such series to the extent permitted by applicable law); provided, however, that
no Extension Period shall extend beyond the Stated Maturity of the principal of
the Securities of such series; provided, further, that during any such Extension
Period, the Company shall not, and shall not permit any Subsidiary to, (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 of or interest or premium, if any,
on or repay, repurchase or redeem any debt security of the Company that ranks
pari passu in all respects with or junior in interest to the Securities of such
series or make any guarantee payments with respect to any guarantee by the
Company of the debt securities of any Subsidiary of the Company that by their
terms rank pari passu in all respects with or junior in interest to the
securities of such series (other than (a) repurchases, redemptions or other
acquisitions of shares of capital stock of the Company in connection with any
employment contract, benefit plan or other similar arrangement with or for the
benefit of one or more employees, officers, directors or consultants, in
connection with a dividend reinvestment or stockholder stock purchase plan or in
connection with the issuance of capital stock of the Company (or securities
convertible into or exercisable for such capital stock) as consideration in an
acquisition transaction entered into prior to any applicable Extension Period,
(b) as a result of any exchange or conversion of any class or series of the
Company's capital stock (or any capital stock of a Subsidiary of the Company)
for any class or series of the Company's capital stock or of any class or series
of the Company's indebtedness for any class or series of the Company's capital
stock, (c) the purchase of fractional interests in shares of the Company's
capital stock pursuant to the conversion or exchange provisions of such capital
stock or the security being converted or exchanged, (d) any declaration of a
dividend in connection with any stockholder's rights plan, or the issuance of
rights, stock or other property under any stockholder's rights plan, or the
redemption or repurchase of rights pursuant thereto, or (e) any dividend in the
form of stock, warrants, options or other rights where the dividend stock or the
stock issuable upon exercise of such warrants, options or other rights is the
same stock as that on which the dividend is being paid or ranks pari passu with
or junior to such stock). Prior to the termination of any such Extension Period,
the Company may further defer the payment of interest, provided that no
Extension Period shall exceed the period or periods specified in such Securities
or extend beyond the Stated Maturity of the principal of such Securities. Upon
termination of any Extension Period and upon the payment of all accrued and
unpaid interest and any Additional Interest then due on any Interest Payment
Date, the Company may elect to begin a new Extension Period, subject to the
above requirements. No interest shall be due and payable during an Extension
Period, except at the end thereof, but each installment of interest that would
otherwise have been due and payable during such Extension Period shall bear
Additional Interest as and to the extent as may be specified as contemplated by
Section 301. The Company shall give the Trustee prior written notice of its
election to begin any such Extension Period as specified pursuant to Section 301
at least one Business Day prior to the next succeeding Interest Payment Date on
which interest on Securities of such series would be payable but for such
deferral or, with respect to any Securities of a series issued to a Regions
Trust, so long as any such Securities are held by such Regions Trust, at least
one Business Day prior to the earlier of (i) the next succeeding date on which
Distributions on the Preferred Securities of such Regions Trust would be payable
but for such deferral, and (ii) the date on which the Property Trustee of such
Regions Trust is required to give notice to any securities exchange or other
applicable self-regulatory organization or to holders of such Preferred
Securities of the record date or the date such Distributions are payable.

         The Trustee, at the expense of the Company, shall promptly give notice
of the Company's election to begin any such Extension Period to the Holders of
the Outstanding Securities of such series.


                                      -30-

<PAGE>   37
SECTION 312.  Right of Set-Off.

         With respect to the Securities of a series issued to a Regions Trust,
notwithstanding anything to the contrary herein, the Company shall have the
right to set-off any payment it is otherwise required to make thereunder in
respect of any such Security to the extent the Company has theretofore made, or
is concurrently on the date of such payment, making a payment under the Regions
Guarantee relating to such Security or to a holder of such Security pursuant to
Section 508 hereof.

SECTION 313.  Agreed Tax Treatment.

         Each Security issued hereunder shall provide that the Company and, by
its acceptance of a Security or a beneficial interest therein, the Holder of,
and any Person that acquires a beneficial interest in, such Security agree that
for United States Federal, state and local tax purposes it is intended that such
Security constitutes indebtedness of the Company for United States Federal,
state and local tax purposes and, with respect to Securities of a series issued
to a Regions Trust, to treat Preferred Securities of such Trust (including but
not limited to all payments and proceeds with respect to such Preferred
Securities) as an undivided beneficial ownership interest in the Securities (and
payments and proceeds therefrom, respectively) for United States Federal, state
and local tax purposes. The provisions of this Indenture shall be interpreted to
further this intention and agreement of the parties.

SECTION 314.  CUSIP Numbers.

         The Company in issuing the Securities may use "CUSIP" numbers (if then
generally in use), and, if so, the Trustee shall use "CUSIP" numbers in notices
of redemption or other related material as a convenience to Holders; provided
that any such notice or other related material may state that no representation
is made as to the correctness of such numbers either as printed on the
Securities or as contained in any notice of redemption or other related material
and that reliance may be placed only on the other identification numbers printed
on the Securities, and any such redemption shall not be affected by any defect
in or omission of such numbers.

SECTION 315.  Shortening of Stated Maturity

         If specified as contemplated by Section 201 or 301 with respect to the
Securities of a particular series, the Company shall have the right to shorten
the Stated Maturity of the principal of the Securities of such series at any
time to any date not earlier than the first date on which the Company has the
right to redeem the Securities of such series. In the event that the Company
elects to shorten the Stated Maturity of the Securities of such series, it shall
give written notice to the Trustee.


                                  ARTICLE FOUR
                           SATISFACTION AND DISCHARGE

  SECTION 401.  Satisfaction and Discharge of Indenture.

         This Indenture shall upon Company Request cease to be of further effect
with respect to any series of Securities specified in such Company Request
(except as to any surviving rights of registration of transfer or exchange of
Securities of such series herein expressly provided for and any right to receive
Additional Amounts, as provided in Section 1011), and the Trustee, upon receipt
of a Company Order, and at the expense of the Company, shall execute proper
instruments acknowledging satisfaction and discharge of this Indenture as to
such series and any coupons appertaining thereto when

                 (1) either

                 (A) all Securities of such series theretofore authenticated and
                 delivered and all coupons, if any, appertaining thereto (other
                 than (i) coupons appertaining to Bearer Securities


                                      -31-
<PAGE>   38
                  surrendered for exchange for Registered Securities and
                  maturing after such exchange, whose surrender is not required
                  or has been waived as provided in Section 305, (ii) Securities
                  and coupons of such series which have been destroyed, lost or
                  stolen and which have been replaced or paid as provided in
                  Section 306, (iii) coupons appertaining to Securities called
                  for redemption and maturing after the relevant Redemption
                  Date, whose surrender has been waived as provided in Section
                  1106, and (iv) Securities and coupons of such series for whose
                  payment money has theretofore been deposited in trust or
                  segregated and held in trust by the Company and thereafter
                  repaid to the Company or discharged from such trust, as
                  provided in Section 1003) have been delivered to the Trustee
                  for cancellation; or

                  (B) all Securities of such series and, in the case of (i) or
                  (ii) below, any coupons appertaining thereto not theretofore
                  delivered to the Trustee for cancellation

                           (i)   have become due and payable, or

                           (ii)  will become due and payable at their Stated
                  Maturity within one year, or

                           (iii) if redeemable at the option of the Company,
                  are to be called for redemption within one year under
                  arrangements satisfactory to the Trustee for the giving of
                  notice of redemption by the Trustee in the name, and at the
                  expense, of the Company, and the Company, in the case of (i),
                  (ii) or (iii) above, has irrevocably deposited or caused to be
                  deposited with the Trustee as trust funds in trust for the
                  purpose an amount in the currency or currencies, currency unit
                  or units or composite currency or currencies in which the
                  Securities of such series are payable, sufficient to pay and
                  discharge the entire indebtedness on such Securities and such
                  coupons not theretofore delivered to the Trustee for
                  cancellation, for principal (and premium or Make-Whole Amount,
                  if any) and interest, and any Additional Interest and
                  Additional Amounts with respect thereto, to the date of such
                  deposit (in the case of Securities which have become due and
                  payable) or the Stated Maturity or Redemption Date, as the
                  case may be;

         (2)  The Company has paid or caused to be paid all other sums payable
hereunder by the Company; and

         (3) The Company has delivered to the Trustee an Officers' Certificate
and an Opinion of Counsel, each stating that all conditions precedent herein
provided for relating to the satisfaction and discharge of this Indenture as to
such series have been complied with.

         Notwithstanding the satisfaction and discharge of this Indenture, the
obligations of the Company to the Trustee and any predecessor Trustee under
Section 606, the obligations of the Company to any Authenticating Agent under
Section 611 and, if money shall have been deposited with and held by the Trustee
pursuant to subclause (B) of clause (1) of this Section, the obligations of the
Trustee under Section 402 and the last paragraph of Section 1003, shall survive.

         In the event that there are Securities of two or more series
outstanding hereunder, the Trustee shall be required to execute an instrument
acknowledging satisfaction and discharge of this Indenture only if requested in
writing to do so with respect to Securities of a particular series as to which
it is Trustee and if the other conditions thereto are met.

SECTION 402.  Application of Trust Funds.

         Subject to the provisions of the last paragraph of Section 1003, all
money deposited with the Trustee pursuant to Section 401 shall be held in trust
and applied by it, in accordance with the provisions of the Securities, the
coupons and this Indenture, to the payment, either directly or through any
Paying Agent (including the Company acting as its own Paying Agent) as the
Trustee may determine, to the Persons entitled thereto, of the principal (and
premium or Make-Whole Amount, if any), and any interest and


                                      -32-
<PAGE>   39

Additional Amounts for whose payment such money has been deposited with or
received by the Trustee, but such money need not be segregated from other funds
except to the extent required by law. Money deposited pursuant to this section
not in violation of this Indenture shall not be subject to claims of holders of
Senior Debt under Article Seventeen.

                                  ARTICLE FIVE
                                    REMEDIES

SECTION 501.  Events of Default.

         Subject to any modifications, additions or deletions relating to any
series of Securities as contemplated pursuant to Section 301, "Event of
Default," wherever used herein with respect to any particular series of
Securities, means any one of the following events (whatever the reason for such
Event of Default whether it shall be occasioned by the provisions of Article
Seventeen and whether or not it shall be voluntary or involuntary or be effected
by operation of law or pursuant to any judgment, decree or order of any court or
any order, rule or regulation of any administrative or governmental body):

         (1) default in the payment of any interest (including any Additional
Interest) upon or any Additional Amounts payable in respect of any Security of
or within that series or of any coupon appertaining thereto, when such interest
(including any Additional Interest), Additional Amounts or coupon becomes due
and payable, and continuance of such default for a period of 30 days; or

         (2) default in the payment of the principal of (or premium or
Make-Whole Amount, if any, on) any Security of that series when it becomes due
and payable at its Maturity; or

         (3) default in the deposit of any sinking fund payment, when and as due
by the terms of any Security of that series; or

         (4) default in the performance, or breach, of any covenant, agreement
or warranty of the Company in this Indenture with respect to any Security of
that series (other than (i) a covenant, agreement or warranty included in this
Indenture solely for the benefit of a series of Securities other than such
series or (ii) a covenant, agreement or warranty a default in whose performance
or whose breach is elsewhere in this Section specifically dealt with), and
continuance of such default or breach for a period of 60 days after there has
been given, by registered or certified mail, to the Company by the Trustee or to
the Company and the Trustee by the Holders of at least 25% in principal amount
of the Outstanding Securities of that series a written notice specifying such
default or breach and requiring it to be remedied and stating that such notice
is a "Notice of Default" hereunder; or

         (5) default under a bond, debenture, note, mortgage, indenture or
instrument under which there may be issued or by which there may be secured or
evidenced any indebtedness for money borrowed by the Company (or by any
Principal Bank Subsidiary, the repayment of which the Company has guaranteed or
for which the Company is directly responsible or liable as obligor or
guarantor), having a principal amount outstanding in excess of $50,000,000
(other than indebtedness which is non-recourse to the Company or the
Subsidiaries) under the terms of the instrument under which the indebtedness is
issued or secured, whether such indebtedness now exists or shall hereafter be
created, which default shall have resulted in such indebtedness being declared
due and payable prior to the date on which it would otherwise have become due
and payable, without such indebtedness having been discharged, or such
acceleration having been rescinded or annulled, or there being deposited with an
unaffiliated depository, in trust, money in the necessary amount to discharge
such indebtedness, within a period of 30 days after there shall have been given,
by registered or certified mail, to the Company by the Trustee or to the Company
and the Trustee by the Holders of at least 25% in principal amount of the
Outstanding Securities of that series a written notice specifying such default
and requiring the Company to cause such indebtedness to be discharged or cause
such acceleration to be rescinded or annulled and stating that such notice is a
"Notice of Default" hereunder; or


                                      -33-
<PAGE>   40
         (6) the Company or any Significant Subsidiary pursuant to or within the
meaning of any Bankruptcy Law:

             (A) commences a voluntary case; or

             (B) consents to the entry of an order for relief against
                 it in an involuntary case; or

             (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; or

             (E) makes an admission in writing of its inability to pay
                 its debts generally as they become due; or

             (F) takes corporate action in furtherance of any such action; or

         (7) a court of competent jurisdiction enters an order or decree under
any Bankruptcy Law that:

             (A) is for relief against the Company or any Significant
                 Subsidiary in an involuntary case; or

             (B) appoints a Custodian of the Company or any Significant
             Subsidiary or for all or substantially all of either of its
             property; or

             (C) orders the liquidation of the Company or any Significant
             Subsidiary, and the order or decree remains unstayed and in effect
             for 90 days; or

             (D) adjudges the Company or any Significant Subsidiary bankrupt or
             insolvent, or approves as properly filed a petition seeking
             reorganization, arrangement, and adjustment or composition of or in
             respect of the Company or any Significant Subsidiary; or

         (8) any other Event of Default provided with respect to Securities of
that series.

         As used in this Section 501, the term "Bankruptcy Law" means Title 11,
U.S. Code or any similar Federal or state bankruptcy, insolvency, reorganization
or other law for the relief of debtors and the term "Custodian" means any
receiver, trustee, assignee, liquidator or other similar official under any
Bankruptcy Law.

SECTION 502.  Acceleration of Maturity; Rescission and Annulment.

         If an Event of Default with respect to Securities of any series at the
time Outstanding occurs and is continuing, then and in every such case the
Trustee or the Holders of not less than 25% in aggregate principal amount of the
Outstanding Securities of each such affected series (voting as a single class)
may declare the principal and premium, if any, (or, if any Securities are
Original Issue Discount Securities or Indexed Securities, such portion of the
principal as may be specified in the terms thereof) of, and the Make-Whole
Amount, if any, on, all the Securities of that series to be due and payable
immediately, by a notice in writing to the Company (and to the Trustee if given
by the Holders), provided that, in the case of the Securities of a series issued
to a Regions Trust, if, upon an Event of Default, the Trustee or the Holders of
not less than 25% in aggregate principal amount of the Outstanding Securities of
that series fail to declare the principal of all the Securities of that series
to be immediately due and payable, the holders of at least 25% in aggregate
Liquidation Amount (as defined in the Trust Agreement under which such Regions
Trust is created) of the corresponding series of Preferred Securities then
outstanding shall have such right by a notice in writing to the Company and the
Trustee; and upon any such declaration such principal and premium, if any, or
specified portion thereof and the accrued interest (including any Additional
Interest) shall become immediately due and payable.


                                      -34-
<PAGE>   41

         At any time after such a declaration of acceleration with respect to
Securities of any series has been made and before a judgment or decree for
payment of the money due has been obtained by the Trustee as hereinafter in this
Article provided, the Holders of a majority in principal amount of the
Outstanding Securities of that series, by written notice to the Company and the
Trustee, may rescind and annul such declaration and its consequences if:

         (1) the Company has paid or deposited with the Trustee a sum sufficient
to pay in the currency, currency unit or composite currency in which the
Securities of such series are payable (except as otherwise specified pursuant to
Section 301 for the Securities of such series):

             (A) all overdue installments of interest on and any Additional
             Amounts payable in respect of all Outstanding Securities of that
             series and any related coupons;

             (B) the principal of (and premium or Make-Whole Amount, if any, on)
             any Outstanding Securities of that series which have become due
             otherwise than by such declaration of acceleration and interest
             thereon at the rate or rates borne by or provided for in such
             Securities;

             (C) to the extent that payment of such interest is lawful, interest
             upon overdue installments of interest (including any Additional
             Interest) and any Additional Amounts at the rate or rates borne by
             or provided for in such Securities; and

             (D) all sums paid or advanced by the Trustee hereunder and the
             reasonable compensation, expenses, disbursements and advances of
             the Trustee, its agents and counsel; and

         (2) all Events of Default with respect to Securities of that series,
other than the nonpayment of the principal of (or premium or Make-Whole Amount,
if any) or interest on Securities of that series which have become due solely by
such declaration of acceleration, have been cured or waived as provided in
Section 513.

         In the case of Securities of a series issued to a Regions Trust, the
holders of a majority in aggregate Liquidation Amount (as defined in the Trust
Agreement under which such Regions Trust is created) of the related series of
Preferred Securities issued by such Regions Trust shall also have the right to
rescind and annul such declaration and its consequences by written notice to the
Company and the Trustee, subject to the satisfaction of the conditions set forth
in Clauses (1) and (2) of this Section 502.

         No such rescission shall affect any subsequent default or impair any
right consequent thereon.

SECTION 503.  Collection of Indebtedness and Suits for Enforcement by Trustee.

         The Company covenants that if:

         (1) default is made in the payment of any installment of interest
(including any Additional Interest) or Additional Amounts, if any, on any
Security of any series and any related coupon when such interest or Additional
Amount becomes due and payable and such default continues for a period of 30
days, or

         (2) default is made in the payment of the principal of (or premium or
Make-Whole Amount, if any, on) any Security of any series at its Maturity, then
the Company will, upon demand of the Trustee, pay to the Trustee, for the
benefit of the Holders of such Securities of such series and coupons, the whole
amount then due and payable on such Securities and coupons for principal (and
premium or Make-Whole Amount, if any) and interest (including any Additional
Interest) and Additional Amounts, with interest upon any overdue principal (and
premium or Make-Whole Amount, if any) and, to the extent that payment of such
interest shall be legally enforceable, upon any overdue installments of interest
(including any Additional Interest) or Additional Amounts, if any, at the rate
or rates borne by or provided for in such Securities, and, in addition thereto,
such further amount as shall be sufficient to cover the costs and


                                      -35-
<PAGE>   42
expenses of collection, including the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel.

         If the Company fails to pay such amounts forthwith upon such demand,
the Trustee, in its own name and as trustee of an express trust, may institute a
judicial proceeding for the collection of the sums so due and unpaid, and may
prosecute such proceeding to judgment or final decree, and may enforce the same
against the Company or any other obligor upon such Securities of such series and
collect the moneys adjudged or decreed to be payable in the manner provided by
law out of the property of the Company or any other obligor upon such Securities
of such series, wherever situated.

         If an Event of Default with respect to Securities of any series occurs
and is continuing, the Trustee may in its discretion proceed to protect and
enforce its rights and the rights of the Holders of Securities of such series
and any related coupons by such appropriate judicial proceedings as the Trustee
shall deem most effectual to protect and enforce any such rights, whether for
the specific enforcement of any covenant or agreement in this Indenture or in
aid of the exercise of any power granted herein, or to enforce any other proper
remedy.

SECTION 504.  Trustee May File Proofs of Claim.

         In case of the pendency of any receivership, insolvency, liquidation,
bankruptcy, reorganization, arrangement, adjustment, composition or other
judicial proceeding relative to the Company or any other obligor upon the
Securities or the property of the Company or of such other obligor or their
creditors, the Trustee (irrespective of whether the principal of the Securities
of any series shall then be due and payable as therein expressed or by
declaration or otherwise and irrespective of whether the Trustee shall have made
any demand on the Company for the payment of overdue principal, premium or
Make-Whole Amount, if any, or interest, (including any Additional Interest)
shall be entitled and empowered, by intervention in such proceeding or otherwise
to take any and all actions authorized under the TIA in order to have any claims
of the Holders and the Trustee allowed in any such proceeding and:

                  (i)  to file and prove a claim for the whole amount, or such
         lesser amount as may be provided for in the Securities of such series,
         of principal (and premium or Make-Whole Amount, if any) and interest
         (including any Additional Interest) and Additional Amounts, if any,
         owing and unpaid in respect of the Securities and to file such other
         papers or documents as may be necessary or advisable in order to have
         the claims of the Trustee (including any claim for the reasonable
         compensation, expenses, disbursements and advances of the Trustee, its
         agents and counsel) and of the Holders allowed in such judicial
         proceeding, and

                  (ii) to collect and receive any moneys or other property
         payable or deliverable on any such claims and to distribute the same;
         and any custodian, receiver, assignee, trustee, liquidator,
         sequestrator (or other similar official) in any such judicial
         proceeding is hereby authorized by each Holder of Securities of such
         series and coupons to make such payments to the Trustee, and in the
         event that the Trustee shall consent to the making of such payments
         directly to the Holders, to pay to the Trustee any amount due to it for
         the reasonable compensation, expenses, disbursements and advances of
         the Trustee and any predecessor Trustee, their agents and counsel, and
         any other amounts due the Trustee or any predecessor Trustee under
         Section 606.

         Nothing herein contained shall be deemed to authorize the Trustee to
authorize or consent to or accept or adopt on behalf of any Holder of a Security
or coupon any plan of reorganization, arrangement, adjustment or composition
affecting the Securities or coupons or the rights of any Holder thereof, or to
authorize the Trustee to vote in respect of the claim of any Holder of a
Security or coupon in any such proceeding provided, however, that the Trustee
may, only on behalf of the Holders, vote for the election of a trustee in
bankruptcy or similar official and be a member of the creditors' committee or
other similar committee.

                                      -36-
<PAGE>   43
SECTION 505.  Trustee May Enforce Claims Without Possession of Securities or
Coupons.


        All rights of action and claims under this Indenture or any of the
Securities or coupons may be prosecuted and enforced by the Trustee without the
possession of any of the Securities or coupons or the production thereof in any
proceeding relating thereto, and any such 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 the payment of the reasonable
compensation, expenses, disbursements and advances of the Trustee, its agents
and counsel, be for the ratable benefit of the Holders of the Securities and
coupons in respect of which such judgment has been recovered.

SECTION 506.  Application of Money Collected.

         Any money collected by the Trustee pursuant to this Article shall be
applied in the following order, at the date or dates fixed by the Trustee and,
in case of the distribution of such money on account of principal (or premium or
Make-Whole Amount, if any) or interest (including any Additional Interest) and
any Additional Amounts, upon presentation of the Securities or coupons, or both,
as the case may be, and the notation thereon of the payment if only partially
paid and upon surrender thereof if fully paid:

         FIRST:  To the payment of all amounts due the Trustee and any
predecessor Trustee under Section 606,

         SECOND: Subject to Article Seventeen, to the payment of the amounts
then due and unpaid upon the Securities and coupons for principal (and premium
or Make-Whole Amount, if any) and interest (including any Additional Interest)
and any Additional Amounts payable, 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 aggregate amounts due and payable on such Securities
and coupons for principal (and premium or Make-Whole Amount, if any), interest
(including any Additional Interest) and Additional Amounts, respectively, and

         THIRD:  To the payment of the remainder, if any, to the Company.

SECTION 507.  Limitation on Suits.

         No Holder of any Security of any series or any related coupon shall
have any right to institute any proceeding, judicial or otherwise, with respect
to this Indenture, or for the appointment of a receiver or trustee, or for any
other remedy hereunder, unless:

         (1) such Holder has previously given written notice to the Trustee of a
continuing Event of Default with respect to the Securities of that series;

         (2) the Holders of not less than 25% in principal amount of the
Outstanding Securities of that series shall have made written request to the
Trustee to institute proceedings in respect of such Event of Default in its own
name as Trustee hereunder;

         (3) such Holder or Holders have offered to the Trustee indemnity
satisfactory to it against the costs, expenses and liabilities to be incurred in
compliance with such request;

         (4) the Trustee for 60 days after its receipt of such notice, request
and offer of indemnity has failed to institute any such proceeding; and

         (5) no direction inconsistent with such written request has been given
to the Trustee during such 60-day period by the Holders of a majority in
principal amount of the Outstanding Securities of that series; it being
understood and intended that no one or more of such Holders shall have any right
in any manner whatever by virtue of, or by availing of, any provision of this
Indenture to affect, disturb or prejudice the rights of any other of such
Holders, or to obtain or to seek to obtain priority or preference over any other
of such Holders or to enforce any right under this Indenture, except in the
manner herein provided and for the equal and ratable benefit of all such
Holders.


                                      -37-
<PAGE>   44

SECTION 508. Unconditional Right of Holders to Receive Principal, Premium or
Make-Whole Amount, if any, Interest and Additional Amounts; Direct Action by
Holders of Preferred Securities.

         Notwithstanding any other provision in this Indenture, the Holder of
any Security or coupon shall have the right which is absolute and unconditional
to receive payment of the principal of (and premium or Make-Whole Amount, if
any) and (subject to Sections 305 and 307) interest on, and any Additional
Amounts in respect of, such Security or payment of such coupon on the respective
due dates expressed in such Security or coupon (or, in the case of redemption,
on the Redemption Date), to convert or exchange such Securities in accordance
with Article Sixteen and to institute suit for the enforcement of any such
payment, and such rights shall not be impaired without the consent of such
Holder. In the case of Securities of a series issued to a Regions Trust, any
holder of the corresponding series of Preferred Securities issued by such
Regions Trust shall have the right, upon the occurrence of an Event of Default
described in Section 501(1) or 501(2), to institute a suit directly against the
Company for enforcement of payment to such holder of principal of (premium, if
any) and (subject to Section 308 and Section 311) interest (including any
Additional Interest) on and any Additional Amounts in respect thereof (including
any Additional Interest) the Securities having a principal amount equal to the
aggregate Liquidation Amount (as defined in the Trust Agreement under which such
Regions Trust is created) of such Preferred Securities of the corresponding
series held by such holder.

SECTION 509.  Restoration of Rights and Remedies.

         If the Trustee or any Holder of a Security or coupon or any holder of
Preferred Securities has instituted any proceeding to enforce any right or
remedy under this Indenture and such proceeding has been discontinued or
abandoned for any reason, or has been determined adversely to the Trustee, to
such Holder or such holder of Preferred Securities, then and in every such case
the Company, the Trustee, the Holders of Securities and coupons, and such holder
of Preferred Securities shall, subject to any determination in such proceeding,
be restored severally and respectively to their former positions hereunder and
thereafter all rights and remedies of the Trustee, the Holders and the holders
of Preferred Securities shall continue as though no such proceeding had been
instituted.

SECTION 510.  Rights and Remedies Cumulative.

         Except as otherwise provided with respect to the replacement or payment
of mutilated, destroyed, lost or stolen Securities or coupons in the last
paragraph of Section 306, no right or remedy herein conferred upon or reserved
to the Trustee or to the Holders of Securities or coupons is intended to be
exclusive of any other right or remedy, and every right and remedy shall, to the
extent permitted by law, be cumulative and in addition to every other right and
remedy given hereunder or now or hereafter existing at law or in equity or
otherwise. The assertion or employment of any right or remedy hereunder, or
otherwise, shall not prevent the concurrent assertion or employment of any other
appropriate right or remedy.

SECTION 511.  Delay or Omission Not Waiver.

         No delay or omission of the Trustee, of any Holder of any Security or
coupon or any holder of any Preferred Security to exercise any right or remedy
accruing upon any Event of Default shall impair any such right or remedy or
constitute a waiver of any such Event of Default or any acquiescence therein.
Every right and remedy given by this Article or by law to the Trustee or to the
Holders and the right and remedy given to the holders of Preferred Securities by
Section 508 may be exercised from time to time, and as often as may be deemed
expedient, by the Trustee or by the Holders of Securities or coupons, or the
holders of Preferred Securities, as the case may be.

SECTION 512.  Control by Holders of Securities.

         The Holders of not less than a majority in principal amount of the
Outstanding Securities of any series 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 with respect
to the Securities of such series, provided that


                                      -38-
<PAGE>   45

         (1) such direction shall not be in conflict with any rule of law or
with this Indenture,

         (2) the Trustee may take any other action deemed proper by the Trustee
which is not inconsistent with such direction, and

         (3) the Trustee need not take any action which might involve it in
personal liability or be unduly prejudicial to the Holders of Securities of such
series not joining therein (but the Trustee shall have no obligation as to the
determination of such undue prejudice).

SECTION 513.  Waiver of Past Defaults.

         The Holders of not less than a majority in principal amount of the
Outstanding Securities of any series and, in the case of any Securities of a
series issued to a Regions Trust, the holders of a Majority in Liquidation
Amount as defined in any Trust Agreement, Preferred Securities issued by such
Regions Trust may on behalf of the Holders of all the Securities or all the
Preferred Securities issued by such Regions Trust of such series and any related
coupons consent to the waiver of any past default hereunder with respect to such
series and its consequences, except a default

         (1) in the payment of the principal of (or premium or Make-Whole
Amount, if any) or interest including Additional Interest on or Additional
Amounts payable in respect of any Security of such series or any related
coupons, or

         (2) in respect of a covenant or provision hereof which under Article
Nine cannot be modified or amended without the consent of the Holder of each
Outstanding Security of such series affected.

         Upon any such waiver, such default shall cease to exist, and any Event
of Default arising therefrom shall be deemed to have been cured, for every
purpose of this Indenture; but no such waiver shall extend to any subsequent or
other default or Event of Default or impair any right consequent thereon.

SECTION 514.  Waiver of Stay, Usury or Extension Laws.

         The Company covenants (to the extent that it may lawfully do so) that
it will not at any time insist upon, or plead, or in any manner whatsoever claim
or take the benefit or advantage of, any usury, stay or extension law wherever
enacted, now or at any time hereafter in force, which may affect the covenants
or the performance of this Indenture; and the Company (to the extent that it may
lawfully do so) hereby expressly waives all benefit or advantage of any such
law, and covenants that it will not hinder, delay or impede the execution of any
power herein granted to the Trustee, but will suffer and permit the execution of
every such power as though no such law had been enacted.

SECTION 515.  Undertaking for Costs.

         All parties to this Indenture agree, and each Holder of any Security by
his 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 Holder, or group of Holders, holding in the aggregate
more than 10% in principal amount of the Outstanding Securities, or to any suit
instituted by any Holder for the enforcement of the payment of the principal of
(or premium or Make-Whole Amount, if any) or interest (including any Additional
Interest) on or Additional Amounts payable with respect to any Security on or
after the respective Stated Maturities expressed in such Security (or in the
case of redemption, on or after the Redemption Date) or to enforce the right to
convert or exchange any Security in accordance with Article Sixteen.


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<PAGE>   46

                                   ARTICLE SIX
                                   THE TRUSTEE

SECTION 601.  Notice of Defaults.

         Within 90 days after the occurrence of any default hereunder with
respect to the Securities of any series, the Trustee shall transmit in the
manner and to the extent provided in TIA Section 313(c), notice of such default
hereunder actually known to a Responsible Officer of the Trustee, 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 or Make-Whole
Amount, if any) or interest (including any Additional Interest) on or any
Additional Amounts with respect to any Security of such series, or in the
payment of any sinking fund installment with respect to the Securities of such
series, the Trustee shall be protected in withholding such notice if and so long
as Responsible Officers of the Trustee in good faith determine that the
withholding of such notice is in the interests of the Holders of the Securities
and coupons of such series; and provided further that in the case of any default
or breach of the character specified in Section 501(4) with respect to the
Securities and coupons of such series, no such notice to Holders shall be given
until at least 60 days after the occurrence thereof. For the purpose of this
Section, the term "default" means any event which is, or after notice or lapse
of time or both would become, an Event of Default with respect to the Securities
of such series.

SECTION 602.  Certain Duties, Responsibilities and Rights of Trustee.

         (a) The Trustee's duties and responsibilities under this Indenture
shall be governed by the Trust Indenture Act.

         (b)  Subject to the provisions of TIA Section 315(a) through 315(d):

                  (1) except during the continuance of an Event of Default, the
         Trustee shall perform only such duties as are expressly undertaken by
         it to perform under this Indenture and no implied covenants or
         obligations shall be read into this Indenture against the Trustee;

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

                  (3) any request or direction of the Company mentioned herein
         shall be sufficiently evidenced by a Company Request or Company Order
         (other than delivery of any Security, together with any coupons
         appertaining thereto, to the Trustee for authentication and delivery
         pursuant to Section 303 which shall be sufficiently evidenced as
         provided therein) and any resolution of the Board of Directors may be
         sufficiently evidenced by a Board Resolution;

                  (4) whenever in the administration of this Indenture the
         Trustee shall deem it desirable that a matter be proved or established
         prior to taking, suffering or omitting any action hereunder, the
         Trustee (unless other evidence be herein specifically prescribed) may,
         in the absence of bad faith on its part, rely upon an Officers'
         Certificate;

                  (5) the Trustee may consult with counsel and as a condition to
         the taking, suffering or omission of any action hereunder may demand an
         Opinion of Counsel, and the advice of such counsel or any Opinion of
         Counsel 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 reliance thereon;

                  (6) the Trustee shall be under no obligation to exercise any
         of the rights or powers vested in it by this Indenture at the request
         or direction of any of the Holders of Securities of any series or


                                      -40-
<PAGE>   47
         any related coupons pursuant to this Indenture, unless such Holders
         shall have offered to the Trustee security or indemnity satisfactory to
         it against the costs, expenses and liabilities which might be incurred
         by it in compliance with such request or direction;

                  (7) 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, direction,
         consent, order, bond, debenture, note, coupon or other paper or
         document, but the Trustee, in its discretion, may make such further
         inquiry or investigation into such facts or matters as it may see fit,
         and, if the Trustee shall determine to make such further inquiry or
         investigation, it shall be entitled to examine the books, records and
         premises of the Company, personally or by agent or attorney;

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

                  (9) if the Trustee is acting as Paying Agent or Transfer Agent
         and Registrar hereunder, the rights, indemnities and protections
         afforded to the Trustee pursuant to this Article VI shall also be
         afforded to such Paying Agent or Transfer Agent and Registrar;

                 (10) the Trustee shall not be deemed to have knowledge of any
         Event of Default unless the Trustee shall have received written notice,
         or a Responsible Officer charged with the administration of this
         Indenture shall have actual knowledge of such Event of Default; and

                 (11) the Trustee shall not be liable for any action taken,
         suffered or omitted by it in good faith and reasonably believed by it
         to be authorized or within the discretion or rights or powers conferred
         upon it by this Indenture. The Trustee shall not be required to expend
         or risk its own funds or otherwise incur any financial liability in the
         performance of any of its duties hereunder, or in the exercise of any
         of its rights or powers, if it shall have reasonable grounds for
         believing that repayment of such funds or indemnity satisfactory to it
         against such risk or liability is not reasonably assured to it.

SECTION 603.  Not Responsible for Recitals or Issuance of Securities.

         The recitals contained herein and in the Securities, except the
Trustee's certificate of authentication, and in any coupons shall be taken as
the statements of the Company, and neither the Trustee nor any Authenticating
Agent assumes any responsibility for their correctness. The Trustee makes no
representations as to the validity or sufficiency of this Indenture or of the
Securities or coupons, except that the Trustee represents that it is duly
authorized to execute and deliver this Indenture, authenticate the Securities
and perform its obligations hereunder. Neither the Trustee nor any
Authenticating Agent shall be accountable for the use or application by the
Company of Securities or the proceeds thereof.

SECTION 604.  May Hold Securities.

         The Trustee, any Paying Agent, Security Registrar, Authenticating Agent
or any other agent of the Company, in its individual or any other capacity, may
become the owner or pledgee of Securities and coupons and, subject to Section
613 and TIA Sections 310(b) and 311, may otherwise deal with the Company with
the same rights it would have if it were not Trustee, Paying Agent, Security
Registrar, Authenticating Agent or such other agent.

SECTION 605. Money Held in Trust.

         Money held by the Trustee in trust hereunder need not be segregated
from other funds except to the extent required by law. The Trustee shall be
under no liability for interest on, or investment of, any money received by it
hereunder except as otherwise agreed in writing with the Company.


                                      -41-
<PAGE>   48
SECTION 606. Compensation and Reimbursement.

         The Company agrees:

         (1) to pay to the Trustee from time to time reasonable compensation for
all services rendered by it hereunder, including extraordinary services rendered
in connection with or during the continuation of a default hereunder (which
compensation shall not be limited by any provision of law in regard to the
compensation of a trustee of an express trust);

         (2) to reimburse each of the Trustee and any predecessor Trustee upon
its request for all reasonable expenses, disbursements and advances incurred or
made by it in accordance with any provision of this Indenture (including the
reasonable compensation and the expenses and disbursements of its agents and
counsel), except to the extent any such expense, disbursement or advance may be
attributable to its gross negligence or bad faith; and

         (3) to indemnify each of the Trustee and any predecessor Trustee and
each of their respective directors, officers, agents and employees for, and to
hold each of them harmless against, any loss, liability or expense, arising out
of or in connection with the acceptance or administration of the trust or trusts
or the performance of its duties hereunder, including the costs and expenses of
defending itself against any claim or liability in connection with the exercise
or performance of any of its powers or duties hereunder except to the extent any
such loss, liability or expense may be attributable to its own gross negligence
or bad faith.

         As security for the performance of the obligations of the Company under
this Section, the Trustee shall have a lien prior to the Securities upon all
property and funds held or collected by the Trustee as such, except funds held
in trust for the payment of principal of (or premium or Make-Whole Amount, if
any) or interest on particular Securities or any coupons.

         When the Trustee incurs expenses or renders services in connection with
an Event of Default described in Section 501(6) and (7), such expenses
(including the fees and expenses of its counsel) and the compensation for such
services are intended to constitute expenses of administration under any
Bankruptcy Law.

         The provisions of this Section shall survive the termination of this
Indenture or the resignation or removal of the Trustee.

SECTION 607.  Corporate Trustee Required; Eligibility.

         There shall at all times be a Trustee hereunder which shall be eligible
to act as Trustee under TIA Section 310(a)(1) and shall have a combined capital
and surplus of at least $50,000,000. If such Trustee or Person publishes reports
of condition at least annually, pursuant to law or the requirements of Federal,
State, Territorial or District of Columbia supervising or examining authority,
then for the purposes of this Section, the combined capital and surplus of such
Trustee or Person 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 the
Trustee shall cease to be eligible in accordance with the provisions of this
Section, it shall resign immediately in the manner and with the effect
hereinafter specified in this Article.

SECTION 608.  Resignation and Removal; Appointment of Successor.

         (a) No resignation or removal of the Trustee and no appointment of a
successor Trustee pursuant to this Article shall become effective until the
acceptance of appointment by the successor Trustee in accordance with the
applicable requirements of Section 609.

         (b) The Trustee may resign at any time with respect to the Securities
of one or more series by giving written notice thereof to the Company. If an
instrument of acceptance by a successor Trustee shall not have been delivered to
the Trustee within 30 days after the giving of such notice of resignation, the


                                      -42-
<PAGE>   49
resigning Trustee may petition any court of competent jurisdiction for the
appointment of a successor Trustee.

         (c) The Trustee may be removed at any time with respect to the
Securities of any series by Act of the Holders of a majority in principal amount
of the Outstanding Securities of such series delivered to the Trustee and to the
Company.

         (d) If at any time:

                  (1) the Trustee shall fail to comply with the provisions of
         Section 613 or TIA Section 310(b) after written request therefor by the
         Company or by any Holder of a Security who has been a bona fide Holder
         of a Security for at least six months, or

                  (2) the Trustee shall cease to be eligible under Section 607
         and shall fail to resign after written request therefor by the Company
         or by any Holder of a Security who has been a bona fide Holder of a
         Security for at least six months, or

                  (3) the Trustee shall become incapable of acting or shall be
         adjudged a bankrupt or insolvent or a receiver of the Trustee or of its
         property shall be appointed 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,
         (i) the Company by or pursuant to a Board Resolution may remove the
         Trustee and appoint a successor Trustee with respect to all Securities,
         or (ii) subject to TIA Section 315(e), any Holder of a Security who has
         been a bona fide Holder of a Security for at least six months may, on
         behalf of himself and all others similarly situated, petition any court
         of competent jurisdiction for the removal of the Trustee with respect
         to all Securities and the appointment of a successor Trustee or
         Trustees.

         (e) If the Trustee shall resign, be removed or become incapable of
acting, or if a vacancy shall occur in the office of Trustee for any cause with
respect to the Securities of one or more series, the Company, by or pursuant to
a Board Resolution, shall promptly appoint a successor Trustee or Trustees with
respect to the Securities of that or those series (it being understood that any
such successor Trustee may be appointed with respect to the Securities of one or
more or all of such series and that at any time there shall be only one Trustee
with respect to the Securities of any particular series) and shall comply with
the requirements of Section 609. If, within one year after such resignation,
removal or incapacity, or the occurrence of such vacancy, a successor Trustee
with respect to the Securities of any series shall be appointed by Act of the
Holders of a majority in principal amount of the Outstanding Securities of such
series delivered to the Company and the retiring Trustee, the successor Trustee
so appointed shall, forthwith upon its acceptance of such appointment, become
the successor Trustee with respect to the Securities of such series and to that
extent supersede the successor Trustee appointed by the Company. If no successor
Trustee with respect to the Securities of any series shall have been so
appointed by the Company or the Holders of Securities and accepted appointment
in the manner hereinafter provided, any Holder of a Security who has been a bona
fide Holder of a Security of such series for at least six months may, on behalf
of himself and all others similarly situated, petition any court of competent
jurisdiction for the appointment of a successor Trustee with respect to
Securities of such series.

         (f) The Company shall give notice of each resignation and each removal
of the Trustee with respect to the Securities of any series and each appointment
of a successor Trustee with respect to the Securities of any series to the
Holders of Securities of such series in the manner provided for notices to the
Holders of Securities in Section 106. Each notice shall include the name of the
successor Trustee with respect to the Securities of such series and the address
of its Corporate Trust Office.

SECTION 609.  Acceptance of Appointment By Successor.

         (a) In case of the appointment hereunder of a successor Trustee with
respect to all Securities, every such successor Trustee 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


                                       -43-
<PAGE>   50
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 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, subject nevertheless to its
claim, if any, provided for in Section 606.

         (b) In case of the appointment hereunder of a successor Trustee with
respect to the Securities of one or more (but not all) series, the Company, the
retiring Trustee and each successor Trustee with respect to the Securities of
one or more series shall execute and deliver an indenture supplemental hereto,
pursuant to Article Nine hereof, wherein each successor Trustee shall accept
such appointment and which (1) shall contain such provisions as shall be
necessary or desirable to transfer and confirm to, and to vest in, each
successor Trustee all the rights, powers, trusts and duties of the retiring
Trustee with respect to the Securities of that or those series to which the
appointment of such successor Trustee relates, (2) if the retiring Trustee is
not retiring with respect to all Securities, shall contain such provisions as
shall be deemed necessary or desirable to confirm that all the rights, powers,
trusts and duties of the retiring Trustee with respect to the Securities of that
or those series as to which the retiring Trustee is not retiring shall continue
to be vested in the retiring Trustee, and (3) shall add to or change any of the
provisions of this Indenture as shall be necessary to provide for or facilitate
the administration of the trusts hereunder by more than one Trustee, it being
understood that nothing herein or in such supplemental indenture shall
constitute such Trustees co-trustees of the same trust and that each such
Trustee shall be trustee of a trust or trusts hereunder separate and apart from
any trust or trusts hereunder administered by any other such Trustee; and upon
the execution and delivery of such supplemental indenture the resignation or
removal of the retiring Trustee shall become effective to the extent provided
therein and each 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 with respect to the Securities of that or those series
to which the appointment of such successor Trustee relates; but, on request of
the Company or any successor Trustee, such retiring Trustee shall duly assign,
transfer and deliver to such successor Trustee all property and money held by
such retiring Trustee hereunder with respect to the Securities of that or those
series to which the appointment of such successor Trustee relates.

         (c) 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) or (b) of this Section, as the case may be.

         (d) 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.

SECTION 610.  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 all or substantially all of the corporate trust
business of the Trustee, shall be the successor of the Trustee hereunder,
provided such corporation shall be otherwise qualified and eligible under this
Article, without the execution or filing of any paper or any further act on the
part of any of the parties hereto. In case any Securities or coupons 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 Securities or coupons so
authenticated with the same effect as if such successor Trustee had itself
authenticated such Securities or coupons. In case any Securities or coupons
shall not have been authenticated by such predecessor Trustee, any such
successor Trustee may authenticate and deliver such Securities or coupons, in
either its own name or that of its predecessor Trustee, with the full force and
effect which this Indenture provides for the certificate of authentication of
the Trustee.


                                      -44-
<PAGE>   51
SECTION 611.  Appointment of Authenticating Agent.

         At any time when any of the Securities remain Outstanding, the Trustee
may appoint an Authenticating Agent or Agents with respect to one or more series
of Securities which shall be authorized to act on behalf of the Trustee to
authenticate Securities of such series issued upon exchange, registration of
transfer or partial redemption or repayment thereof or pursuant to Section 306,
and Securities 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. Any such appointment shall be evidenced by an
instrument in writing signed by a Responsible Officer of the Trustee, a copy of
which instrument shall be promptly furnished to the Company. Wherever reference
is made in this Indenture to the authentication and delivery of Securities 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
reasonably acceptable to the Company and, except as may otherwise be provided
pursuant to Section 301, shall at all times be a bank or trust company or
corporation organized and doing business and in good standing under the laws of
the United States of America or of any State 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 authorities. If such Authenticating Agent
publishes reports of condition at least annually, pursuant to law or the
requirements of the aforesaid supervising or examining authority, then 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. In case 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 further act
on the part of the Trustee or the Authenticating Agent.

         An Authenticating Agent for any series of Securities may at any time
resign by giving written notice of resignation to the Trustee for such series
and to the Company. The Trustee for any series of Securities may at any time
terminate the agency of an Authenticating Agent by giving written notice of
termination to such Authenticating Agent and to the Company. Upon receiving such
a notice of resignation or upon such a 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 for such series may appoint a successor
Authenticating Agent which shall be acceptable to the Company and shall give
notice of such appointment to all Holders of Securities of or within the series
with respect to which such Authenticating Agent will serve in the manner set
forth in Section 106. Any successor Authenticating Agent upon acceptance of its
appointment hereunder shall become vested with all the rights, powers and duties
of its predecessor hereunder, with 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 Company agrees to pay to each Authenticating Agent from time to
time reasonable compensation including reimbursement of its reasonable expenses
for its services under this Section.

         If an appointment with respect to one or more series is made pursuant
to this Section, the Securities of such series may have endorsed thereon, in


                                      -45-
<PAGE>   52

addition to or in lieu of the Trustee's certificate of authentication, an
alternate certificate of authentication substantially in the following form:

         This is one of the Securities of the series designated therein referred
to in the within-mentioned Indenture.

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

                   By:                             as Authenticating Agent
                      ----------------------------
                   By:                              Authorized Officer
                      ----------------------------

SECTION 612.  Certain Duties and Responsibilities.

         No provision of this Indenture shall require the Trustee to expend or
risk its own funds or otherwise incur any financial liability in the performance
of any of its duties hereunder, or in the exercise of any of its rights or
powers, if it shall have reasonable grounds for believing that repayment of such
funds or indemnity satisfactory to it against such risk or liability is not
reasonably assured to it. Whether or not therein expressly so provided, every
provision of this Indenture relating to the conduct or affecting the liability
of or affording protection to the Trustee shall be subject to the provisions of
this Section.

SECTION 613.  Conflicting Interests.

         If the Trustee has or shall acquire a conflicting interest within the
meaning of the Trust Indenture Act, the Trustee shall either eliminate such
interest or resign, to the extent and in the manner provided by, and subject to
the provisions of, the Trust Indenture Act and this Indenture. To the extent
permitted by such Act, the Trustee shall not be deemed to have a conflicting
interest by virtue of being a trustee under this Indenture with respect to
Securities of more than one series. In case an Event of Default shall occur and
be continuing, the Trustee shall exercise such of its rights and powers under
the applicable 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.

SECTION 614.  Preferential Collection of Claims Against Company.

         If and when the Trustee shall be or become a creditor of the Company
(or any other obligor upon the Securities), the Trustee shall be subject to the
provisions of the TIA regarding the collection of claims against the Company (or
any such other obligor).

                                  ARTICLE SEVEN
                HOLDERS' LISTS AND REPORTS BY TRUSTEE AND COMPANY

SECTION 701.  Disclosure of Names and Addresses of Holders.

         Every Holder of Securities or coupons, by receiving and holding the
same, agrees with the Company and the Trustee that neither the Company nor the
Trustee nor any Authenticating Agent nor any Paying Agent nor any Security
Registrar nor any director, officer, agent or employee of any of them shall be
held accountable by reason of the disclosure of any information as to the names
and addresses of the Holders of Securities or coupons in accordance with TIA
Section 312, regardless of the source from which such information was derived,
and that the Trustee shall not be held accountable by reason of mailing any
material pursuant to a request made under TIA Section 312(b).

SECTION 702.  Reports by Trustee.

         Within 60 days after March 15 of each year commencing with the first
March 15 after the first issuance of Securities pursuant to this Indenture, the
Trustee shall transmit by mail to all Holders of Securities as provided in TIA
Section 313(c) a brief report dated as of such March 15 if and to the extent
required by TIA Section 313(a).


                                      -46-
<PAGE>   53
         A copy of each such report shall, at the time of such transmission to
Holders, be filed by the Trustee with the Commission and with the Company and,
provided the Trustee has received written notification by the Company that any
Securities are listed on any stock exchange, with each stock exchange upon which
the Trustee has been so notified that such Securities are listed.

SECTION 703.  Reports by Company.

         The Company will:

         (1) 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) which 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 it will file with the Trustee and the Commission, in
accordance with rules and regulations prescribed from time to time by the
Commission, such of the supplementary and periodic information, documents and
reports which may be required pursuant to Section 13 of the Exchange Act in
respect of a security listed and registered on a national securities exchange as
may be prescribed from time to time in such rules and regulations;

         (2) file with the Trustee and the Commission, in accordance with 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 of this Indenture as may be required from time
to time by such rules and regulations; and

         (3) transmit by mail to the Holders of Securities, within 30 days after
the filing thereof with the Trustee, in the manner and to the extent provided in
TIA Section 313(c), such summaries of any information, documents and reports
required to be filed by the Company pursuant to paragraphs (1) or (2) of this
Section as may be required by rules and regulations prescribed from time to time
by the Commission.

SECTION 704.  Company to Furnish Trustee Names and Addresses of Holders.

         The Company will furnish or cause to be furnished to the Trustee:

         (1) semi-annually, not later than 15 days after the Regular Record Date
for interest for each series of Securities, a list, in such form as the Trustee
may reasonably require, of the names and addresses of the Holders of Registered
Securities of such series as of such Regular Record Date, or if there is no
Regular Record Date for interest for such series of Securities, semi-annually,
upon such dates as are set forth in the Board Resolution or indenture
supplemental hereto authorizing such series, and

         (2) 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, so long as the Trustee is the Security
Registrar, no such lists shall be required to be furnished.

                                 ARTICLE EIGHT
                CONSOLIDATION, MERGER, SALE, LEASE OR CONVEYANCE

SECTION 801. Consolidations and Mergers of Company and Sales, Leases and
Conveyances Permitted Subject to Certain Conditions.

         The Company may consolidate with, or sell, lease or convey all or
substantially all of its assets to, or merge with or into any other Person,
provided that in any such case, (i) either the Company shall be the


                                      -47-
<PAGE>   54
continuing entity, or the successor (if other than the Company) entity shall be
a Person organized and existing under the laws of the United States or a State
thereof and such successor entity shall expressly assume the due and punctual
payment of the principal of (and premium or Make-Whole Amount, if any) and any
interest (including any Additional Interest and all Additional Amounts, if any,
payable pursuant to Section 1011) on all of the Securities, according to their
tenor, the conversion or exchange rights shall be provided for in accordance
with Article Sixteen, if applicable, or as otherwise specified pursuant to
Section 301, and the due and punctual performance and observance of all of the
covenants and conditions of this Indenture to be performed by the Company by
supplemental indenture, complying with Article Nine hereof, satisfactory to the
Trustee, executed and delivered to the Trustee by such Person; (ii) immediately
after giving effect to such transaction and treating any indebtedness which
becomes an obligation of the Company or any Subsidiary as a result thereof as
having been incurred by the Company or such Subsidiary at the time of such
transaction, no Event of Default, and no event which, after notice or the lapse
of time, or both, would become an Event of Default, shall have occurred and be
continuing; (iii) in the case of the Securities of a series issued to a Regions
Trust, such consolidation, merger, conveyance, transfer or lease is permitted
under the Trust Agreement under which Regions Trust is created and the related
Regions Guarantee and does not give rise to any breach or violation of the
related Trust Agreement or Regions Guarantee; and (iv) if, as a result of any
such consolidation or merger or such conveyance, transfer or lease, properties
or assets of the Company would become subject to a mortgage, pledge, lien,
security interest or other encumbrance which would not be permitted by this
Indenture, the Company or such successor Person, as the case may be, shall take
such steps as shall be necessary effectively to secure the Securities equally
and ratably with (or prior to) all indebtedness secured thereby.

SECTION 802.  Rights and Duties of Successor Corporation.

         In case of any such consolidation, merger, sale, lease or conveyance
and upon any such assumption by the successor entity, such successor entity
shall succeed to and be substituted for the Company, with the same effect as if
it had been named herein as the party of the first part, and the predecessor
entity, except in the event of a lease, shall be relieved of any further
obligation under this Indenture and the Securities. Such successor entity
thereupon may cause to be signed, and may issue either in its own name or in the
name of the Company, any or all of the Securities issuable hereunder which
theretofore shall not have been signed by the Company and delivered to the
Trustee; and, upon the order of such successor entity, instead of the Company,
and subject to all the terms, conditions and limitations in this Indenture
prescribed, the Trustee shall authenticate and shall deliver any Securities
which previously shall have been signed and delivered by the officers of the
Company to the Trustee for authentication, and any Securities which such
successor entity thereafter shall cause to be signed and delivered to the
Trustee for that purpose. All the Securities so issued shall in all respects
have the same legal rank and benefit under this Indenture as the Securities
theretofore or thereafter issued in accordance with the terms of this Indenture
as though all of such Securities had been issued at the date of the execution
hereof.

         In case of any such consolidation, merger, sale, lease or conveyance,
such changes in phraseology and form (but not in substance) may be made in the
Securities thereafter to be issued as may be appropriate.

SECTION 803.  Officers' Certificate and Opinion of Counsel.

         Any consolidation, merger, sale, lease or conveyance permitted under
Section 801 is also subject to the condition that the Trustee receive an
Officers' Certificate and an Opinion of Counsel to the effect that any such
consolidation, merger, sale, lease or conveyance, and the assumption by any
successor entity, complies with the provisions of this Article and that all
conditions precedent herein provided for relating to such transaction have been
complied with.


                                      -48-
<PAGE>   55
                                  ARTICLE NINE
                             SUPPLEMENTAL INDENTURES

SECTION 901.  Supplemental Indentures Without Consent of Holders.

         Without the consent of any Holders of Securities or coupons, the
Company, when authorized by or pursuant to a Board Resolution, and the Trustee,
at any time and from time to time, may enter into one or more indentures
supplemental hereto, in form reasonably satisfactory to the Trustee, for any of
the following purposes:

         (1) to evidence the  succession of another  Person to the Company and
the  assumption by any such successor of the covenants of the Company herein
and in the Securities; or

         (2) to add to the covenants of the Company for the benefit of the
Holders of all or any series of Securities (and, if such covenants are to be for
the benefit of less than all series of Securities, stating that such covenants
are expressly being included solely for the benefit of such series) or to
surrender any right or power herein conferred upon the Company; or

         (3) to add any additional Events of Default for the benefit of the
Holders of all or any series of Securities (and if such Events of Default are to
be for the benefit of less than all series of Securities, stating that such
Events of Default are expressly being included solely for the benefit of such
series); provided, however, that in respect of any such additional Events of
Default such supplemental indenture may provide for a particular period of grace
after default (which period may be shorter or longer than that allowed in the
case of other defaults) or may provide for an immediate enforcement upon such
default or may limit the remedies available to the Trustee upon such default or
may limit the right of the Holders of a majority in aggregate principal amount
of that or those series of Securities to which such additional Events of Default
apply to waive such default; or

         (4) to add to or change any of the provisions of this Indenture to
provide that Bearer Securities may be registrable as to principal, to change or
eliminate any restrictions on the payment of principal of or any premium,
Make-Whole Amount or Interest on Bearer Securities, to permit Bearer Securities
to be issued in exchange for Registered Securities, to permit Bearer Securities
to be issued in exchange for Bearer Securities of other authorized denominations
or to permit or facilitate the issuance of Securities in uncertificated form,
provided that any such action shall not adversely affect the interests of the
Holders of Securities of any series or any related coupons in any material
respect; or

         (5) to add to, change or eliminate any of the provisions of this
Indenture in respect of any series of Securities, provided that any such
addition, change or elimination shall (i) neither (A) apply to any Security of
any series created prior to the execution of such supplemental indenture and
entitled to the benefit of such provision, nor (B) modify the rights of the
Holder of any such Security with respect to such provision; or (ii) become
effective only when there is no Security Outstanding; or

         (6)  to secure the Securities; or

         (7) to establish the form or terms of Securities of any series and any
related coupons as permitted by Sections 201 and 301, including the provisions
and procedures relating to Securities convertible into or exchangeable for other
securities or property of the Company; or

         (8) to evidence and provide for the acceptance of appointment hereunder
by a successor Trustee with respect to the Securities of one or more series and
to add to or change any of the provisions of this Indenture as shall be
necessary to provide for or facilitate the administration of the trusts
hereunder by more than one Trustee; or

         (9) to make provision with respect to the conversion or exchange rights
of Holders pursuant to the requirements of Article Sixteen, including providing
for the conversion or exchange of the securities into any security or property
of the Company; or


                                      -49-
<PAGE>   56
        (10) to cure any ambiguity, to correct or supplement any provision
herein which may be defective or inconsistent with any other provision herein,
or to make any other provisions with respect to matters or questions arising
under this Indenture which shall not be inconsistent with the provisions of this
Indenture or to make any other changes, provided that in each case, such
provisions shall not adversely affect the interests of the Holders of Securities
of any series or any related coupons in any material respect or, in the case of
the Securities of a series issued to a Regions Trust and for so long as any of
the corresponding series of Preferred Securities issued by such Regions Trust
shall remain outstanding, the holders of such Preferred Securities; or

        (11) to close this Indenture with respect to the authentication and
delivery of additional series of Securities or to qualify, or maintain
qualification of, this Indenture under the TIA; or

        (12) to supplement any of the provisions of this Indenture to such
extent as shall be necessary to permit or facilitate the defeasance and
discharge of any series of Securities pursuant to Sections 401, 1402 and 1403;
provided in each case that any such action shall not adversely affect the
interests of the Holders of Securities of such series and any related coupons or
any other series of Securities in any material respect.

SECTION 902.  Supplemental Indentures with Consent of Holders.

         With the consent of the Holders of not less than a majority in
principal amount of all Outstanding Securities affected by such supplemental
indenture, by Act of said Holders delivered to the Company and the Trustee, the
Company, when authorized by or pursuant to a Board Resolution, and the Trustee
may enter into an indenture or indentures supplemental hereto for the purpose of
adding any provisions to or changing in any manner or eliminating any of the
provisions of this Indenture or of modifying in any manner the rights of the
Holders of Securities and any related coupons under this Indenture; provided,
however, that no such supplemental indenture shall, without the consent of the
Holder of each Outstanding Security affected thereby:

         (1) change the Stated Maturity of the principal of (or premium or
Make-Whole Amount, if any, on) or any installment of principal of or interest
on, any Security; or reduce the principal amount thereof or the rate or amount
of interest (including any Additional Interest) thereon or any Additional
Amounts payable in respect thereof, or any premium or Make-Whole Amount payable
upon the redemption thereof, or change any obligation of the Company to pay
Additional Amounts pursuant to Section 1011 (except as contemplated by Section
801(i) and permitted by Section 901(1)), or reduce the amount of the principal
of an Original Issue Discount Security or Indexed Security or Make-Whole Amount,
if any, that would be due and payable upon a declaration of acceleration of the
Maturity thereof pursuant to Section 502 or the amount thereof provable in
bankruptcy pursuant to Section 504, or adversely affect any right of repayment
at the option of the Holder of any Security, or change any Place of Payment
where, or the currency or currencies, currency unit or units or composite
currency or currencies in which, the principal of any Security or any premium or
Make-Whole Amount or any Additional Amounts payable in respect thereof or the
interest thereon is payable, or impair the right to institute suit for the
enforcement of any such payment on or after the Stated Maturity thereof (or, in
the case of redemption or repayment at the option of the Holder, on or after the
Redemption Date or the Repayment Date, as the case may be); or

         (2) reduce the percentage in principal amount of the Outstanding
Securities of any series, the consent of whose Holders is required for any such
supplemental indenture, or the consent of whose Holders is required for any
waiver with respect to such series (or compliance with certain provisions of
this Indenture or certain defaults hereunder and their consequences) provided
for in this Indenture, or reduce the requirements of Section 1504 for quorum or
voting; or

         (3) modify any of the provisions of this Section, Section 513 or
Section 1012, except to increase the required percentage to effect such action
or to provide that certain other provisions of this Indenture cannot be modified
or waived without the consent of the Holder of each Outstanding Security
affected thereby; or


                                      -50-
<PAGE>   57
         (4) make any change that adversely affects the right to convert or
exchange any Security as provided in Article Sixteen or pursuant to Section 301
(except as permitted by Section 901(9)) or decrease the conversion or exchange
rate or increase the conversion or exchange price of any such Security;
provided, further, that, in the case of the Securities of a series issued to a
Regions Trust, so long as any of the corresponding series of Preferred
Securities issued by such Regions Trust remains outstanding, (i) no such
amendment shall be made that adversely affects the holders of such Preferred
Securities in any material respect, and no termination of this Indenture shall
occur, and no waiver of any Event of Default or compliance with any covenant
under this Indenture shall be effective, without the prior consent of the
holders of at least a majority of the aggregate Liquidation Amount of such
Preferred Securities then outstanding unless and until the principal (and
premium, if any) of the Securities of such series and all accrued and, subject
to Section 307, unpaid interest (including any Additional Interest) thereon have
been paid in full and (ii) no amendment shall be made to Section 508 of this
Indenture that would impair the rights of the holders of Preferred Securities
provided therein without the prior consent of the holders of each Preferred
Security then outstanding unless and until the principal (and premium, if any)
of the Securities of such series and all accrued and(subject to Section 307)
unpaid interest (including any Additional Interest) thereon have been paid in
full.

         A supplemental indenture that changes or eliminates any covenant or
other provision of this Indenture that has expressly been included solely for
the benefit of one or more particular series of Securities or Preferred
Securities, or which modifies the rights of the Holders of Securities or holders
of Preferred Securities of such series with respect to such covenant or other
provision, shall be deemed not to affect the rights under this Indenture of the
Holders of Securities or holders of Preferred Securities of any other series.

         It shall not be necessary for any Act of Holders under this Section to
approve the particular form of any proposed supplemental indenture, but it shall
be sufficient if such Act shall approve the substance thereof.

SECTION 903.  Execution of Supplemental Indentures.

         In executing, or accepting the additional trusts created by, any
supplemental indenture permitted by this Article or the modification thereby of
the trusts created by this Indenture, the Trustee shall be entitled to receive,
and shall be fully protected in relying upon, an Opinion of Counsel and an
Officers' Certificate stating that the execution of such supplemental indenture
is authorized or permitted by this Indenture and that all conditions precedent
to the execution of such supplemental indenture have been complied with. The
Trustee may, but shall not be obligated to, enter into any such supplemental
indenture which affects the Trustee's own rights, duties or immunities under
this Indenture or otherwise.

SECTION 904.  Effect of Supplemental Indentures.

         Upon the execution of any supplemental indenture under this Article,
this Indenture shall be modified in accordance therewith, and such supplemental
indenture shall form a part of this Indenture for all purposes; and every Holder
of Securities theretofore or thereafter authenticated and delivered hereunder
and of any coupon appertaining thereto shall be bound thereby.

SECTION 905.  Conformity with Trust Indenture Act.

         Every supplemental indenture executed pursuant to this Article shall
conform to the requirements of the Trust Indenture Act as then in effect.

SECTION 906.  Reference in Securities to Supplemental Indentures.

         Securities of any series authenticated and delivered after the
execution of any supplemental indenture pursuant to this Article may, and shall
if required by the Trustee, bear a notation in form approved by the Trustee as
to any matter provided for in such supplemental indenture. If the Company shall
so determine, new Securities of any series so modified as to conform, in the
opinion of the Trustee and the


                                      -51-
<PAGE>   58
Company, to any such supplemental indenture may be prepared and executed by the
Company and authenticated and delivered by the Trustee in exchange for
Outstanding Securities of such series.

SECTION 907.  Notice of Supplemental Indentures.

         Promptly after the execution by the Company and the Trustee of any
supplemental indenture pursuant to the provisions of Section 902, the Company
shall give notice thereof to the Holders of each Outstanding Security affected,
in the manner provided for in Section 106, setting forth in general terms the
substance of such supplemental indenture.

SECTION 908.  Subordination Unimpaired.

         No provision in any supplemental indenture that adversely affects the
superior position of the holders of Senior Debt then outstanding shall be
effective against holders of Senior Debt without the consent of such holders.

                                   ARTICLE TEN
                                    COVENANTS

SECTION 1001.  Payment of Principal, Premium or Make-Whole Amount, if any,
Interest and Additional Amounts.

         The Company covenants and agrees for the benefit of the Holders of each
series of Securities that it will duly and punctually pay the principal of (and
premium or Make-Whole Amount, if any) and interest on and any Additional Amounts
payable in respect of the Securities of that series in accordance with the terms
of such series of Securities, any coupons appertaining thereto and this
Indenture. Unless otherwise specified as contemplated by Section 301 with
respect to any series of Securities, any interest due on and any Additional
Amounts payable in respect of Bearer Securities on or before Maturity, other
than Additional Amounts, if any, payable as provided in Section 1011 in respect
of principal of (or premium or Make-Whole Amount, if any, on) such a Security,
shall be payable only upon presentation and surrender of the several coupons for
such interest installments as are evidenced thereby as they severally mature.
Unless otherwise specified with respect to Securities of any series pursuant to
Section 301, at the option of the Company, all payments of principal may be paid
by check to the registered Holder of the Registered Security or other person
entitled thereto against surrender of such Security.

SECTION 1002.  Maintenance of Office or Agency.

         If Securities of a series are issued as Registered Securities, the
Company shall maintain in each Place of Payment for any series of Securities an
office or agency where Securities of that series may be presented or surrendered
for payment or conversion, where Securities of that series may be surrendered
for registration of transfer or exchange, where Securities of that series may be
converted or exchanged in accordance with Article Sixteen, and where notices and
demands to or upon the Company in respect of the Securities of that series and
this Indenture may be served. If Securities of a series are issued as Bearer
Securities, the Company will maintain: (A) in the City of Birmingham, Alabama or
in the Borough of Manhattan, The City of New York, an office or agency where any
Registered Securities of that series may be presented or surrendered for payment
or conversion, where any Registered Securities of that series may be surrendered
for exchange, where notices and demands to or upon the Company in respect of the
Securities of that series and this Indenture may be served and where Bearer
Securities of that series and related coupons may be presented or surrendered
for payment or conversion in the circumstances described in the following
paragraph (and not otherwise); (B) subject to any laws or regulations applicable
thereto, in a Place of Payment for that series which is located outside the
United States, an office or agency where Securities of that series and related
coupons may be presented and surrendered for payment (including payment of any
Additional Amounts payable on Securities of that series pursuant to Section
1011) or conversion; provided, however, that if the Securities of that series
are listed on the Luxembourg Stock Exchange, The International Stock Exchange of
the United Kingdom or any other stock exchange located outside the United States
and such stock exchange shall so require, the Company will maintain a Paying

                                      -52-
<PAGE>   59
Agent for the Securities of that series in Luxembourg, London or any other
required city located outside the United States, as the case may be, so long as
the Securities of that series are listed on such exchange; and (C) subject to
any laws or regulations applicable thereto, in each Place of Payment for that
series located outside the United States an office or agency where any
Securities of that series may be surrendered for registration of transfer, where
Securities of that series may be surrendered for exchange and where notices and
demands to or upon the Company in respect of the Securities of that series and
this Indenture may be served. The Company will give prompt written notice to the
Trustee of the location, and any change in the location, of each such office or
agency. 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, surrenders, notices and demands may be made or served at the
Corporate Trust Office of the Trustee, except that Bearer Securities of that
series and the related coupons may be presented and surrendered for payment
(including payment of any Additional Amounts payable on Bearer Securities of
that series pursuant to Section 1011) at the offices specified in the Security,
in London, England, and the Company hereby appoints the same as its agent to
receive such respective presentations, surrenders, notices and demands, and the
Company hereby appoints the Trustee its agent to receive all such presentations,
surrenders, notices and demands.

         Unless otherwise specified with respect to any Securities pursuant to
Section 301, no payment of principal, premium, Make-Whole Amount or interest on
or Additional Amounts in respect of Bearer Securities shall be made at any
office or agency of the Company in the United States or by check mailed to any
address in the United States or by transfer to an account maintained with a bank
located in the United States; provided, however, that, if the Securities of a
series are payable in Dollars, payment of principal of and any premium and
interest on any Bearer Security (including any Additional Amounts or Make-Whole
Amount payable on Securities of such series pursuant to Section 1011) shall be
made at the office of the Company's Paying Agent in the City of Birmingham,
Alabama or the Borough of Manhattan, The City of New York, if (but only if)
payment in Dollars of the full amount of such principal, premium, interest,
Additional Amounts or Make-Whole Amount, as the case may be, at all offices or
agencies outside the United States maintained for the purpose by the Company in
accordance with this Indenture, is illegal or effectively precluded by exchange
controls or other similar restrictions.

         The Company may from time to time designate one or more other offices
or agencies where the Securities of one or more series and related coupons, if
any, may be presented or surrendered for any or all of such purposes, and may
from time to time rescind such designations; provided, however, that no such
designation or rescission shall in any manner relieve the Company of its
obligation to maintain an office or agency in accordance with the requirements
set forth above for Securities of any series for such purposes. The Company will
give prompt written notice to the Trustee of any such designation or rescission
and of any change in the location of any such other office or agency.

         Unless otherwise specified with respect to any Securities pursuant to
Section 301, if and so long as the Securities of any series (i) are denominated
in a Foreign Currency or (ii) may be payable in a Foreign Currency, or so long
as it is required under any other provision of the Indenture, then the Company
will maintain with respect to each such series of Securities, or as so required,
at least one Exchange Rate Agent.

SECTION 1003.  Money for Securities Payments to Be Held in Trust.

         If the Company shall at any time act as its own Paying Agent with
respect to any series of any Securities and any related coupons, it will, on or
before each due date of the principal of (and premium or Make-Whole Amount, if
any), or interest on or Additional Amounts in respect of, any of the Securities
of that series, segregate and hold in trust for the benefit of the Persons
entitled thereto a sum in the currency or currencies, currency unit or units or
composite currency or currencies in which the Securities of such series are
payable (except as otherwise specified pursuant to Section 301 for the
Securities of such series) sufficient to pay the principal (and premium or
Make-Whole Amount, if any) or interest or Additional Amounts so becoming due
until such sums shall be paid to such Persons or otherwise disposed of as herein
provided, and will promptly notify the Trustee of its action or failure so to
act.

                                      -53-
<PAGE>   60
         Whenever the Company shall have one or more Paying Agents for any
series of Securities and any related coupons, it will, on or before each due
date of the principal of (and premium or Make-Whole Amount, if any), or interest
on or Additional Amounts in respect of, any Securities of that series, deposit
with a Paying Agent a sum (in the currency or currencies, currency unit or units
or composite currency or currencies described in the preceding paragraph)
sufficient to pay the principal (and premium or Make-Whole Amount, if any) or
interest or Additional Amounts, so becoming due, such sum to be held in trust
for the benefit of the Persons entitled to such principal, premium, Make-Whole
Amount or interest or Additional Amounts and (unless such Paying Agent is the
Trustee) the Company will promptly notify the Trustee of its action or failure
so to act.

         The Company will cause each Paying Agent other than the Trustee to
execute and deliver to the Trustee an instrument in which such Paying Agent
shall agree with the Trustee, subject to the provisions of this Section, that
such Paying Agent will:

         (1) hold all sums held by it for the payment of principal of (and
premium or Make-Whole Amount, if any) or interest on Securities or Additional
Amounts in trust for the benefit of the Persons entitled thereto until such sums
shall be paid to such Persons or otherwise disposed of as herein provided;

         (2) give the Trustee written notice of any default by the Company (or
any other obligor upon the Securities) in the making of any such payment of
principal (and premium or Make-Whole Amount, if any) or interest or Additional
Amounts; and

         (3) at any time during the continuance of any such default upon the
written request of the Trustee, forthwith pay to the Trustee all sums so held in
trust by such Paying Agent.

         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
by Company Order 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 trusts 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 sums.

         Except as otherwise provided in the Securities of any series, any money
deposited with the Trustee or any Paying Agent, or then held by the Company, in
trust for the payment of the principal of (and premium or Make-Whole Amount, if
any) or interest on, or any Additional Amounts in respect of, any Security of
any series and remaining unclaimed for two years after such principal (and
premium or Make-Whole Amount, if any), interest or Additional Amounts has become
due and payable shall be paid to the Company upon Company Request or (if then
held by the Company) shall be discharged from such trust; and the Holder of such
Security shall thereafter, as an unsecured general creditor, look only to the
Company for payment of such principal of (and premium or Make-Whole Amount, if
any) or interest on, or any Additional Amounts in respect of, any Security,
without interest thereon, and all liability of the Trustee or such Paying Agent
with respect to such trust money, and all liability of the Company as trustee
thereof, shall thereupon cease; provided, however, that the Trustee or such
Paying Agent, before being required to make any such repayment, may at the
expense of the Company cause to be published once, in an Authorized Newspaper,
notice that such money remains unclaimed and that, after a date specified
therein, which shall not be less than 30 days from the date of such publication,
any unclaimed balance of such money then remaining will be repaid to the
Company.

SECTION 1004.  Restrictions During Extension Period.

         During any Extension Period, the Company shall not, and shall not
permit any Subsidiary to, (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 of or
interest or premium, if any, on or repay, repurchase or redeem any debt security
of the Company that ranks pari passu in all respects with or junior in interest
to the Securities of such series or make any guarantee payments with respect to
any guarantee by the Company of the debt securities of any Subsidiary of the


                                      -54-
<PAGE>   61
Company that by their terms rank pari passu in all respects with or junior in
interest to the securities of such series (other than (a) repurchases,
redemptions or other acquisitions of shares of capital stock of the Company in
connection with any employment contract, benefit plan or other similar
arrangement with or for the benefit of one or more employees, officers,
directors or consultants, in connection with a dividend reinvestment or
stockholder stock purchase plan or in connection with the issuance of capital
stock of the Company (or securities convertible into or exercisable for such
capital stock) as consideration in an acquisition transaction entered into prior
to any applicable Extension Period, (b) as a result of any exchange or
conversion of any class or series of the Company's capital stock (or any capital
stock of a Subsidiary of the Company) for any class or series of the Company's
capital stock or of any class or series of the Company's indebtedness for any
class or series of the Company's capital stock, (c) the purchase of fractional
interests in shares of the Company's capital stock pursuant to the conversion or
exchange provisions of such capital stock or the security being converted or
exchanged, (d) any declaration of a dividend in connection with any
stockholder's rights plan, or the issuance of rights, stock or other property
under any stockholder's rights plan, or the redemption or repurchase of rights
pursuant thereto, or (e) any dividend in the form of stock, warrants, options or
other rights where the dividend stock or the stock issuable upon exercise of
such warrants, options or other rights where the dividend stock or the stock
issuable upon exercise of such warrants, options or other rights is the same
stock as that on which the dividend is being paid or ranks pari passu with or
junior to such stock).

SECTION 1005.  Existence.

         Subject to Article Eight, the Company will do or cause to be done all
things necessary to preserve and keep in full force and effect the existence,
rights (charter and statutory) and franchises of the Company and its
Subsidiaries; provided, however, that the Company shall not be required to
preserve any such right or franchise if the Board of Directors shall determine
that the preservation thereof is no longer desirable in the conduct of the
business of the Company and its Subsidiaries as a whole and that the loss
thereof is not disadvantageous in any material respect to the Holders of
Securities of any series.

SECTION 1006.  Maintenance of Properties.

         The Company will cause all of its material properties used or useful in
the conduct of its business or the business of any Subsidiary to be maintained
and kept in good condition, repair and working order and supplied with all
necessary equipment and will cause to be made all necessary repairs, renewals,
replacements, betterments and improvements thereof, all as in the judgment of
the Company may be necessary so that the business carried on in connection
therewith may be properly and advantageously conducted at all times; provided,
however, that nothing in this Section shall prevent the Company or any
Subsidiary from selling or otherwise disposing of its properties in the ordinary
course of its business.

SECTION 1007.  [Reserved].

SECTION 1008.  Payment of Taxes and Other Claims.

         The Company will pay or discharge or cause to be paid or discharged,
before the same shall become delinquent, (1) all taxes, assessments and
governmental charges levied or imposed upon it or any Subsidiary or upon the
income, profits or property of the Company or any Subsidiary, and (2) all lawful
claims for labor, materials and supplies which, if unpaid, might by law become a
lien upon the property of the Company or any Subsidiary; provided, however, that
the Company shall not be required to pay or discharge or cause to be paid or
discharged any such tax, assessment, charge or claim whose amount, applicability
or validity is being contested in good faith by appropriate proceedings.

SECTION 1009.  Provision of Financial Information.

         Whether or not the Company is subject to Section 13 or 15(d) of the
Exchange Act, the Company will, to the extent permitted under the Exchange Act,
file with the Commission the annual reports, quarterly reports and other
documents which the Company would have been required to file with the Commission
pursuant to such Section 13 or 15(d) (the "Financial Statements") if the Company
were so subject, such


                                      -55-
<PAGE>   62
documents to be filed with the Commission on or prior to the respective dates
(the "Required Filing Dates") by which the Company would have been required so
to file such documents if the Company were so subject.

         The Company will also in any event (x) within 15 days of each Required
Filing Date file with the Trustee copies of annual reports, quarterly reports
and other documents which the Company would have been required to file with the
Commission pursuant to Section 13 or 15(d) of the Exchange Act if the Company
were subject to such Sections, and (y) if filing such documents by the Company
with the Commission is not permitted under the Exchange Act, promptly upon
written request and payment of the reasonable cost of duplication and delivery,
supply copies of such documents to any prospective Holder.

SECTION 1010.  Statement as to Compliance.

         The Company will deliver to the Trustee within 120 days after the end
of each fiscal year, a brief certificate from the principal executive officer,
principal financial officer or principal accounting officer as to his or her
knowledge of the Company's compliance with all conditions and covenants under
this Indenture and, in the event of any noncompliance, specifying such
noncompliance and the nature and status thereof. For purposes of this Section
1010, such compliance shall be determined without regard to any period of grace
or requirement of notice under this Indenture.

SECTION 1011.  Additional Amounts.

         If any Securities of a series provide for the payment of Additional
Amounts, the Company will pay to the Holder of any Security of such series or
any coupon appertaining thereto Additional Amounts as may be specified as
contemplated by Section 301. Whenever in this Indenture there is mentioned, in
any context except in the case of Section 502(1), the payment of the principal
of or any premium, Make-Whole Amount or interest on, or in respect of, any
Security of any series or payment of any related coupon or the net proceeds
received on the sale or exchange of any Security of any series, such mention
shall be deemed to include mention of the payment of Additional Amounts provided
by the terms of such series established pursuant to Section 301 to the extent
that, in such context, Additional Amounts are, were or would be payable in
respect thereof pursuant to such terms and express mention of the payment of
Additional Amounts (if applicable) in any provisions hereof shall not be
construed as excluding Additional Amounts in those provisions hereof where such
express mention is not made.

         Except as otherwise specified as contemplated by Section 301, if the
Securities of a series provide for the payment of Additional Amounts, at least
10 days prior to the first Interest Payment Date with respect to that series of
Securities (or if the Securities of that series will not bear interest prior to
Maturity, the first day on which a payment of principal and any premium is
made), and at least 10 days prior to each date of payment of principal and any
premium or Make-Whole Amount or interest if there has been any change with
respect to the matters set forth in the below-mentioned Officers' Certificate,
the Company will furnish the Trustee and the Company's principal Paying Agent or
Paying Agents, if other than the Trustee, with an Officers' Certificate
instructing the Trustee and such Paying Agent or Paying Agents whether such
payment of principal of and any premium or interest on the Securities of that
series shall be made to Holders of Securities of that series or any related
coupons who are not United States persons without withholding for or on account
of any tax, assessment or other governmental charge described in the Securities
of or within the series. If any such withholding shall be required, then such
Officers' Certificate shall specify by country the amount, if any, required to
be withheld on such payments to such Holders of Securities of that series or
related coupons and the Company will pay to the Trustee or such Paying Agent the
Additional Amounts, if any, required by the terms of such Securities. In the
event that the Trustee or any Paying Agent, as the case may be, shall not so
receive the above mentioned certificate, then the Trustee or such Paying Agent
shall be entitled (i) to assume that no such withholding or deduction is
required with respect to any payment of principal or interest with respect to
any Securities of a series or related coupons until it shall have received a
certificate advising otherwise and (ii) to make all payments of principal and
interest with respect to the Securities of a series or related coupons without
withholding or deductions until otherwise advised. The Company covenants to
indemnify the Trustee and any Paying Agent and their respective officers,
directors, employees and agents for, and to hold them harmless against, any
loss,


                                      -56-
<PAGE>   63
liability or expense (including legal fees and expenses) reasonably
incurred without gross negligence or bad faith on their part arising out of or
in connection with actions taken or omitted by any of them in reliance on any
Officers' Certificate furnished pursuant to this Section or in reliance on the
Company's not furnishing such an Officers' Certificate.

SECTION 1012.  Waiver of Certain Covenants.

         Subject to the rights of the holders of Preferred Securities specified
in Section 902, the Company may omit in any particular instance to comply with
any term, provision or condition set forth in Sections 1004 to 1009, inclusive,
and with any other term, provision or condition with respect to the Securities
of any series specified in accordance with Section 301, if before or after the
time for such compliance the Holders of at least a majority in principal amount
of all outstanding Securities of such series, by Act of such Holders, either
waive such compliance in such instance or generally waive compliance with such
covenant or condition, but no such waiver shall extend to or affect such
covenant or condition except to the extent so expressly waived, and, until such
waiver shall become effective, the obligations of the Company and the duties of
the Trustee in respect of any such term, provision or condition shall remain in
full force and effect.

SECTION 1013.  Additional Sums.

         In the case of the Securities of a series issued to a Regions Trust, so
long as no Event of Default has occurred and is continuing and except as
otherwise specified as contemplated by Section 201 or Section 301, in the event
that (i) a Regions Trust is the Holder of all of the Outstanding Securities of
such series and (ii) a Tax Event in respect of such Regions Trust shall have
occurred and be continuing, the Company shall pay to such Regions Trust (and its
permitted successors or assigns under the Trust Agreement under which such
Regions Trust is created) as Holder of the Securities of such series for so long
as such Regions Trust (or its permitted successor or assignee) is the registered
holder of any Securities of such series, such additional sums as may be
necessary in order that the amount of Distributions (including any Additional
Amounts (as defined in such Trust Agreement)) then due and payable by such
Regions Trust on the related Preferred Securities and Common Securities that at
any time remain outstanding in accordance with the terms thereof shall not be
reduced as a result of any Additional Taxes (the "Additional Sums"). Whenever in
this Indenture or the Securities there is a reference in any context to the
payment of principal of or interest on the Securities, such mention shall be
deemed to include mention of the payments of the Additional Sums provided for in
this paragraph to the extent that, in such context, Additional Sums are, were or
would be payable in respect thereof pursuant to the provisions of this paragraph
and express mention of the payment of Additional Sums (if applicable) in any
provisions hereof shall not be construed as excluding Additional Sums in those
provisions hereof where such express mention is not made; provided, however,
that the deferral of the payment of interest pursuant to Section 311 or the
Securities shall not defer the payment of any Additional Sums that may be due
and payable.

SECTION 1014.  Additional Covenants.

         The Company covenants and agrees with each Holder of Securities of each
series that it shall not, and it shall not permit any Subsidiary of the Company
to, (a) declare or pay any dividends or distributions on, or redeem, purchase,
acquire or make a liquidation payment with respect to, any shares of the
Company's capital stock, or (b) make any payment of principal of or interest or
premium, if any, on or repay, repurchase or redeem any debt securities of the
Company that rank pari passu in all respects with or junior in interest to the
Securities of such series or make any guarantee payments with respect to any
guarantee by the Company of debt securities of any Subsidiary of the Company if
such guarantee ranks pari passu in all respects with or junior in interest to
the Securities (other than (a) repurchases, redemptions or other acquisitions of
shares of capital stock of the Company in connection with any employment
contract, benefit plan or other similar arrangement with or for the benefit of
one or more employees, officers, directors or consultants, in connection with a
dividend reinvestment or stockholder stock purchase plan or in connection with
the issuance of capital stock of the Company (or securities convertible into or
exercisable for such capital stock) as consideration in an acquisition
transaction entered into prior to any applicable Extension Period, (b) as a
result of any exchange or conversion of any class or series of the


                                      -57-
<PAGE>   64
Company's capital stock (or any capital stock of a Subsidiary of the Company)
for any class or series of the Company's capital stock or of any class or series
of the Company's indebtedness for any class or series of the Company's capital
stock, (c) the purchase of fractional interests in shares of the Company's
capital stock pursuant to the conversion or exchange provisions of such capital
stock or the security being converted or exchanged, (d) any declaration of a
dividend in connection with any stockholder's rights plan, or the issuance of
rights, stock or other property under any stockholder's rights plan, or the
redemption or repurchase of rights pursuant thereto, or (e) any dividend in the
form of stock, warrants, options or other rights where the dividend stock or the
stock issuable upon exercise of such warrants, options or other rights is the
same stock as that on which the dividend is being paid or ranks pari passu with
or junior to such stock), if at such time (i) there shall have occurred any
event of which the Company has actual knowledge that (A) with the giving of
notice or the lapse of time or both, would constitute an Event of Default with
respect to the Securities of such series and (B) in respect of which the Company
shall not have taken reasonable steps to cure, (ii) if the Securities of such
series are held by a Regions Trust, the Company shall be in default with respect
to its payment of any obligations under the Regions Guarantee relating to the
Preferred Securities issued by such Regions Trust, or (iii) the Company shall
have given written notice of its election to begin an Extension Period with
respect to the Securities of such series as provided herein and shall not have
rescinded such notice, or such Extension Period, or any extension thereof, shall
be continuing.

         The Company also covenants with each Holder of Securities of a series
issued to a Regions Trust (i) to maintain directly or indirectly 100% ownership
of the Common Securities of such Regions Trust; provided, however, that any
permitted successor of the Company hereunder may succeed to the Company's
ownership of such Common Securities, (ii) as holder of such Common Securities,
not to voluntarily terminate, wind-up or liquidate such Trust, other than (a) in
connection with a distribution of the Securities of such series to the holders
of the related Preferred Securities in liquidation of such Trust, or (b) in
connection with certain mergers, consolidations or amalgamations permitted by
the related Trust Agreement, and (iii) to use its reasonable efforts, consistent
with the terms and provisions of such Trust Agreement, to cause such Regions
Trust to remain classified as a grantor trust and not an association taxable as
a corporation for United States federal income tax purposes.

SECTION 1015.  Original Issue Discount

         For each year during which any Securities that were issued with
original issue discount are Outstanding, the Company shall furnish to each
Paying Agent in a timely fashion such information as may be reasonably requested
by each Paying Agent in order that each Paying Agent may prepare the information
which it is required to report for such year on Internal Revenue Service Forms
1096 and 1099 pursuant to Section 6049 of the Internal Revenue Code of 1986, as
amended. Such information shall include the amount of original issue discount
includable in income for each $1,000 of principal amount at Stated Maturity of
outstanding Securities during such year.

                                 ARTICLE ELEVEN
                            REDEMPTION OF SECURITIES

SECTION 1101.  Applicability of Article.

         Securities of any series which are redeemable before their Stated
Maturity shall be redeemable in accordance with their terms and (except as
otherwise specified as contemplated by Section 301 for Securities of any series)
in accordance with this Article.


                                      -58-
<PAGE>   65
SECTION 1102.  Election to Redeem; Notice to Trustee.

         The election of the Company to redeem any Securities, including
coupons, if any, shall be evidenced by or pursuant to a Board Resolution. In
case of any redemption at the election of the Company of less than all of the
Securities or coupons, if any, of any series, the Company shall, at least 45
days prior to the giving of the notice of redemption in Section 1104 (unless a
shorter notice shall be satisfactory to the Trustee), notify the Trustee, in
writing, of such Redemption Date, Redemption Price and of the principal amount
of Securities of such series to be redeemed. In the case of any redemption of
Securities prior to the expiration of any restriction on such redemption
provided in the terms of such Securities or elsewhere in this Indenture or
pursuant to an election of the Company which is subject to a condition specified
in the terms of such Securities, the Company shall furnish the Trustee with an
Officers' Certificate and Opinion of Counsel evidencing compliance with such
restriction or condition.

SECTION 1103.  Selection by Trustee of Securities to Be Redeemed.

         If less than all the Securities of any series are to be redeemed, the
particular Securities to be redeemed shall be selected not more than 60 days
prior to the Redemption Date by the Trustee, from the Outstanding Securities of
such series issued on such date with the same terms not previously called for
redemption, by such method as the Trustee shall deem fair and appropriate and
which may provide for the selection for redemption of portions (equal to the
minimum authorized denomination for Securities of that series or any integral
multiple thereof) of the principal amount of Securities of such series of a
denomination larger than the minimum authorized denomination for Securities of
that series. The Trustee shall make the selection from Securities of the series
that are Outstanding and that have not previously been called for redemption and
may provide for the selection for redemption of portions (equal to the minimum
authorized denomination for Securities, including coupons, if any, of that
series or any integral multiple thereof).

         If any Security selected for partial redemption is converted in part
before termination of the conversion or exchange right with respect to the
portion of the Security so selected, the converted or exchanged portion of such
Security shall be deemed (so far as may be) to be the portion selected for
redemption. Securities which have been converted or exchanged during a selection
of Securities to be redeemed shall be treated by the Trustee as Outstanding for
the purpose of such selection. In any case where more than one Security is
registered in the same name, the Trustee in its discretion may treat the
aggregate principal amount so registered as if it were represented by one
Security.

         The Trustee shall promptly notify the Company and the Security
Registrar (if other than itself) in writing of the Securities selected for
redemption and, in the case of any Securities selected for partial redemption,
the principal amount thereof to be redeemed.

         For all purposes of this Indenture, unless the context otherwise
requires, all provisions relating to the redemption of Securities shall relate,
in the case of any Security redeemed or to be redeemed only in part, to the
portion of the principal amount of such Security which has been or is to be
redeemed.

SECTION 1104.  Notice of Redemption.

         Notice of redemption shall be given in the manner provided in Section
106, not less than 30 days nor more than 60 days prior to the Redemption Date,
unless a shorter period is specified by the terms of such series established
pursuant to Section 301, to each Holder of Securities to be redeemed, but
failure to give such notice in the manner herein provided to the Holder of any
Security designated for redemption as a whole or in part, or any defect in the
notice to any such Holder, shall not affect the validity of the proceedings for
the redemption of any other such Security or portion thereof.

         Any notice that is mailed to the Holders of Registered Securities in
the manner herein provided shall be conclusively presumed to have been duly
given, whether or not the Holder receives the notice.

                                      -59-
<PAGE>   66
         All notices of redemption shall state:

         (1)  the Redemption Date;

         (2) the Redemption Price, accrued interest to the Redemption Date
payable as provided in Section 1106, if any, and Additional Amounts, if any;

         (3) if less than all Outstanding Securities of any series are to be
redeemed, the identification (and, in the case of partial redemption, the
principal amount) of the particular Security or Securities to be redeemed;

         (4) in case any Security is to be redeemed in part only, that on and
after the Redemption Date, upon surrender of such Security, the holder will
receive, without a charge, a new Security or Securities of authorized
denominations for the principal amount thereof remaining unredeemed;

         (5) that on the Redemption Date the Redemption Price and accrued
interest to the Redemption Date payable as provided in Section 1106, if any,
will become due and payable upon each such Security, or the portion thereof, to
be redeemed and, if applicable, that interest thereon shall cease to accrue on
and after said date;

         (6) the Place or Places of Payment where such Securities, together in
the case of Bearer Securities with all coupons appertaining thereto, if any,
maturing after the Redemption Date, are to be surrendered for payment of the
Redemption Price and accrued interest, if any, or for conversion or exchange;

         (7)  that the redemption is for a sinking fund, if such is the case;

         (8) that, unless otherwise specified in such notice, Bearer Securities
of any series, if any, surrendered for redemption must be accompanied by all
coupons maturing subsequent to the date fixed for redemption or the amount of
any such missing coupon or coupons will be deducted from the Redemption Price,
unless security or indemnity satisfactory to the Company, the Trustee for such
series and any Paying Agent is furnished;

         (9) if Bearer Securities of any series are to be redeemed and any
Registered Securities of such series are not to be redeemed, and if such Bearer
Securities may be exchanged for Registered Securities not subject to the
redemption on this Redemption Date pursuant to Section 305 or otherwise, the
last date, as determined by the Company, on which such exchanges may be made;

        (10) the CUSIP number of such Security, if any, provided that neither
the Company nor the Trustee shall have any responsibility for any such CUSIP
number; and

        (11) if applicable, that a Holder of Securities who desires to convert
or exchange Securities to be redeemed must satisfy the requirements for
conversion or exchange contained in such Securities, the then existing
conversion or exchange price or rate and the date and time when the option to
convert or exchange shall expire and the place or places where such Securities
may be surrendered for conversion.

         Notice of redemption of Securities to be redeemed shall be given by the
Company or, at the Company's written request, by the Trustee in the name and at
the expense of the Company.

SECTION 1105.  Deposit of Redemption Price.

         On or prior to any Redemption Date, the Company shall deposit with the
Trustee or with a Paying Agent (or, if the Company is acting as its own Paying
Agent, which it may not do in the case of a sinking fund payment under Article
Twelve, segregate and hold in trust as provided in Section 1003) an amount of
money in the currency or currencies, currency unit or units or composite
currency or currencies in which the Securities of such series are payable
(except as otherwise specified pursuant to Section 301 for the Securities of
such series) sufficient to pay on the Redemption Date the Redemption Price of,
and (except if


                                      -60-
<PAGE>   67
the Redemption Date shall be an Interest Payment Date) accrued interest
(including Additional Interest) on, all the Securities or portions thereof which
are to be redeemed on that date.

SECTION 1106.  Securities Payable on Redemption Date.

         Notice of redemption having been given as aforesaid, the Securities so
to be redeemed shall, on the Redemption Date, become due and payable at the
Redemption Price therein specified in the currency or currencies, currency unit
or units or composite currency or currencies in which the Securities of such
series are payable (except as otherwise specified pursuant to Section 301 for
the Securities of such series) (together with accrued interest, including
Additional Interest) if any, to the Redemption Date), and from and after such
date (unless the Company shall default in the payment of the Redemption Price
and accrued interest including Additional Interest) such Securities shall, if
the same were interest-bearing, cease to bear interest and the coupons for such
interest appertaining to any Bearer Securities so to be redeemed, except to the
extent provided below, shall be void. Except as provided in the next succeeding
paragraph, upon surrender of any such Security for redemption in accordance with
said notice, together with all coupons, if any, appertaining thereto maturing
after the Redemption Date, such Security shall be paid by the Company at the
Redemption Price, together with accrued interest, if any, to the Redemption
Date; provided, however, that installments of interest (including Additional
Interest) on Bearer Securities whose Stated Maturity is on or prior to the
Redemption Date shall be payable only at an office or agency located outside the
United States (except as otherwise provided in Section 1002) and, unless
otherwise specified as contemplated by Section 301, only upon presentation and
surrender of coupons for such interest (including Additional Interest); and
provided further that except as otherwise provided with respect to Securities
convertible or exchangeable into other securities or property of the Company
installments of interest on Registered Securities whose Stated Maturity is on or
prior to the Redemption Date shall be payable to the Holders of such Securities,
or one or more Predecessor Securities, registered as such at the close of
business on the relevant Record Dates according to their terms and the
provisions of Section 307.

         If any Bearer Security surrendered for redemption shall not be
accompanied by all appurtenant coupons maturing after the Redemption Date, such
Security may be paid after deducting from the Redemption Price an amount equal
to the face amount of all such missing coupons, or the surrender of such missing
coupon or coupons may be waived by the Company and the Trustee if there be
furnished to them such security or indemnity as they may require to save each of
them and any Paying Agent harmless. If thereafter the Holder of such Security
shall surrender to the Trustee or any Paying Agent any such missing coupon in
respect of which a deduction shall have been made from the Redemption Price,
such Holder shall be entitled to receive the amount so deducted; provided,
however, that interest (and any Additional Amounts) represented by coupons shall
be payable only at an office or agency located outside the United States (except
as otherwise provided in Section 1002) and, unless otherwise specified as
contemplated by Section 301, only upon presentation and surrender of those
coupons. If any Security called for redemption shall not be so paid upon
surrender thereof for redemption, the principal, (and premium or Make-Whole
Amount, if any) shall, until paid, bear interest (including Additional Interest)
from the Redemption Date at the rate borne by the Security.

SECTION 1107.  Securities Redeemed in Part.

         Any Security which is to be redeemed only in part (pursuant to the
provisions of this Article or of Article Twelve) shall be surrendered at a Place
of Payment therefor (with, if the Company or the Trustee so requires, due
endorsement by, or a written instrument of transfer in form satisfactory to the
Company and the Trustee duly executed by, the Holder thereof or his attorney
duly authorized in writing) and the Company shall execute and the Trustee shall
authenticate and deliver to the Holder of such Security without service charge a
new Security or Securities of the same series, of any authorized denomination as
requested by such Holder in aggregate principal amount equal to and in exchange
for the unredeemed portion of the principal of the Security so surrendered.


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SECTION 1108.  Right of Redemption of Securities Initially Issued to a Regions
Trust.


         In the case of the Securities of a series initially issued to a Regions
Trust, if specified as contemplated by Section 301, the Company, at its option,
may redeem such Securities in whole but not in part upon the occurrence and
during the continuation of a Tax Event, Capital Treatment Event or Investment
Company Event of such Securities at any time within 90 days following the
occurrence of such Tax Event, Capital Treatment Event or Investment Company
Event in respect of such Regions Trust, in each case at a Redemption Price
specified as contemplated by Section 301. Except as provided in the foregoing
sentence or as may otherwise be specified with respect to any series of
Securities in a Board Resolution or supplemental indenture, the Company shall
not have the option to redeem any Securities initially issued to a Regions
Trust, in whole or in part, prior to the Stated Maturity thereof.


                                 ARTICLE TWELVE
                                  SINKING FUNDS

SECTION 1201.  Applicability of Article.

         The provisions of this Article shall be applicable to any sinking fund
for the retirement of Securities of a series except as otherwise specified as
contemplated by Section 301 for Securities of such series.

         The minimum amount of any sinking fund payment provided for by the
terms of Securities of any series is herein referred to as a "mandatory sinking
fund payment," and any payment in excess of such minimum amount provided for by
the terms of such Securities of any series is herein referred to as an "optional
sinking fund payment." If provided for by the terms of any Securities of any
series, the cash amount of any mandatory sinking fund payment may be subject to
reduction as provided in Section 1202. Each sinking fund payment shall be
applied to the redemption of Securities of any series as provided for by the
terms of Securities of such series.

SECTION 1202.  Satisfaction of Sinking Fund Payments with Securities.

         The Company may, in satisfaction of all or any part of any mandatory
sinking fund payment with respect to the Securities of a series, (1) deliver
Outstanding Securities of such series (other than any previously called for
redemption) together in the case of any Bearer Securities of such series with
all unmatured coupons appertaining thereto and (2) apply as a credit Securities
of such series which have been redeemed either at the election of the Company
pursuant to the terms of such Securities or through the application of permitted
optional sinking fund payments pursuant to the terms of such Securities, as
provided for by the terms of such Securities, or which have otherwise been
acquired by the Company; provided that such Securities so delivered or applied
as a credit have not been previously so credited. Such Securities shall be
received and credited for such purpose by the Trustee at the applicable
Redemption Price specified in such Securities for redemption through operation
of the sinking fund and the amount of such mandatory sinking fund payment shall
be reduced accordingly.

SECTION 1203.  Redemption of Securities for Sinking Fund.

         Not less than 60 days prior to each sinking fund payment date for
Securities of any series, the Company will deliver to the Trustee an Officers'
Certificate specifying the amount of the next ensuing mandatory sinking fund
payment for that series pursuant to the terms of that series, the portion
thereof, if any, which is to be satisfied by payment of cash in the currency or
currencies, currency unit or units or composite currency or currencies in which
the Securities of such series are payable (except as otherwise specified
pursuant to Section 301 for the Securities of such series) and the portion
thereof, if any, which is to be satisfied by delivering and crediting Securities
of that series pursuant to Section 1202, and the optional amount, if any, to be
added in cash to the next ensuing mandatory sinking fund payment, and will also
deliver to the Trustee any Securities to be so delivered and credited. If such
Officers' Certificate shall specify an optional amount to be added in cash to
the next ensuing mandatory sinking fund payment, the Company shall thereupon be
obligated to pay the amount therein specified. Not more than 60 nor less than 30
days before each such sinking fund payment date the Trustee shall select the
Securities to be redeemed upon such sinking fund payment date in the manner
specified in Section 1103 and cause notice of the redemption thereof to be given
in the name of and at the expense of the Company in the manner provided


                                      -62-
<PAGE>   69
in Section 1104. Such notice having been duly given, the redemption of such
Securities shall be made upon the terms and in the manner stated in Section 1106
and 1107.

                                ARTICLE THIRTEEN
                       REPAYMENT AT THE OPTION OF HOLDERS

SECTION 1301.  Applicability of Article.

         Repayment of Securities of any series before their Stated Maturity at
the option of Holders thereof shall be made in accordance with the terms of such
Securities, if any, and (except as otherwise specified by the terms of such
series established pursuant to Section 301) in accordance with this Article.

SECTION 1302.  Repayment of Securities.

         Securities of any series subject to repayment in whole or in part at
the option of the Holders thereof will, unless otherwise provided in the terms
of such Securities, be repaid at a price equal to the principal amount thereon,
together with interest, if any, thereof accrued to the Repayment Date specified
in or pursuant to the terms of such Securities. The Company covenants that on or
before the Repayment Date it will deposit with the Trustee or with a Paying
Agent (or, if the Company is acting as its own Paying Agent, segregate and hold
in trust as provided in Section 1003) an amount of money in the currency or
currencies, currency unit or units or composite currency or currencies in which
the Securities of such series are payable (except as otherwise specified
pursuant to Section 301 for the Securities of such series) sufficient to pay the
principal (or, if so provided by the terms of the Securities of any series, a
percentage of the principal) of, and (except if the Repayment Date shall be an
Interest Payment Date) accrued interest on, all the Securities or portion
thereof, as the case may be, to be repaid on such date.

SECTION 1303.  Exercise of Option.

         Securities of any series subject to repayment at the option of the
Holders thereof will contain an "Option to Elect Repayment" form on the reverse
of such Securities. In order for any Security to be repaid at the option of the
Holder, the Trustee must receive at the Place of Payment therefor specified in
the terms of such Security (or at such other place or places of which the
Company shall from time to time notify the Holders of such Securities) not
earlier than 60 days nor later than 30 days prior to the Repayment Date (1) the
Security so providing for such repayment together with the "Option to Elect
Repayment" form on the reverse thereof duly completed by the Holder (or by the
Holder's attorney duly authorized in writing) or (2) a telegram, telex,
facsimile transmission or a letter from a member of a national securities
exchange, or the National Association of Securities Dealers, Inc. ("NASD"), or a
commercial bank or trust company in the United States setting forth the name of
the Holder of the Security, the principal amount of the Security, the principal
amount of the Security to be repaid, the CUSIP number, if any, or a description
of the tenor and terms of the Security, a statement that the option to elect
repayment is being exercised thereby and a guarantee that the Security to be
repaid, together with the duly completed form entitled "Option to Elect
Repayment" on the reverse of the Security, will be received by the Trustee not
later than the third Business Day after the date of such telegram, telex,
facsimile transmission or letter; provided, however, that such telegram, telex,
facsimile transmission or letter shall only be effective if such Security and
form duly completed are received by the Trustee by such third Business Day. If
less than the entire principal amount of such Security is to be repaid in
accordance with the terms of such Security, the principal amount of such
Security to be repaid, in increments of the minimum denomination for Securities
of such series, and the denomination or denominations of the Security or
Securities to be issued to the Holder for the portion of the principal amount of
such Security surrendered that is not to be repaid, must be specified. The
principal amount of any Security providing for repayment at the option of the
Holder thereof may not be repaid in part if, following such repayment, the
unpaid principal amount of such Security would be less than the minimum
authorized denomination of Securities of or within the series of which such
Security to be repaid is a part. Except as otherwise may be provided by the
terms of any Security providing for repayment at the option of the Holder
thereof, exercise of the repayment option by the Holder shall be irrevocable
unless waived by the Company.


                                      -63-
<PAGE>   70
SECTION 1304.  When Securities Presented for Repayment Become Due and Payable.

         If Securities of any series providing for repayment at the option of
the Holders thereof shall have been surrendered as provided in this Article and
as provided by or pursuant to the terms of such Securities, such Securities or
the portions thereof, as the case may be, to be repaid shall become due and
payable and shall be paid by the Company on the Repayment Date therein
specified, and on and after such Repayment Date (unless the Company shall
default in the payment of such Securities on such Repayment Date) such
Securities shall, if the same were interest bearing, cease to bear interest and
the coupons for such interest appertaining to any Bearer Securities so to be
repaid, except to the extent provided below, shall be void. Upon surrender of
any such Security for repayment in accordance with such provisions, together
with all coupons, if any, appertaining thereto maturing after the Repayment
Date, the principal amount of such security so to be repaid shall be paid by the
Company, together with accrued interest, if any, to the Repayment Date;
provided, however, that coupons whose Stated Maturity is on or prior to the
Repayment Date shall be payable only at an office or agency located outside the
United States (except as otherwise provided in Section 1002) and, unless
otherwise specified pursuant to Section 301, only upon presentation and
surrender of such coupons; and provided further that, in the case of Registered
Securities, installments of interest, if any, whose Stated Maturity is on or
prior to the Repayment Date shall be payable (but without interest thereon,
unless the Company shall default in the payment thereof) to the Holders of such
Securities, or one or more Predecessor Securities, registered as such at the
close of business on the relevant Record Dates according to their terms and the
provisions of Section 307.

         If any Bearer Security surrendered for repayment shall not be
accompanied by all appurtenant coupons maturing after the Repayment Date, such
Security may be paid after deducting from the amount payable therefor as
provided in Section 1302 an amount equal to the face amount of all such missing
coupons, or the surrender of such missing coupon or coupons may be waived by the
Company and the Trustee if there be furnished to them such security or indemnity
as they may require to save each of them and any Paying Agent harmless. If
thereafter the Holder of such Security shall surrender to the Trustee or any
Paying Agent any such missing coupon in respect of which a deduction shall have
been made as provided in the preceding sentence, such Holder shall be entitled
to receive the amount so deducted; provided, however, that interest represented
by coupons shall be payable only at an office or agency located outside the
United States (except as otherwise provided in Section 1002) and, unless
otherwise specified as contemplated by Section 301, only upon presentation and
surrender of those coupons. If the principal amount of any Security surrendered
for repayment shall not be so repaid upon surrender thereof, such principal
amount (together with interest, if any, thereon accrued to such Repayment Date)
shall, until paid, bear interest from the Repayment Date at the rate of interest
or Yield to Maturity (in the case of Original Issue Discount Securities) set
forth in such Security.

SECTION 1305.  Securities Repaid in Part.

         Upon surrender of any Registered Security which is to be repaid in part
only, the Company shall execute and the Trustee shall authenticate and deliver
to the Holder of such Security, without service charge and at the expense of the
Company, a new Registered Security or Securities of the same series, of any
authorized denomination specified by the Holder, in an aggregate principal
amount equal to and in exchange for the portion of the principal of such
Security so surrendered which is not to be repaid.

                                ARTICLE FOURTEEN
                       DEFEASANCE AND COVENANT DEFEASANCE

SECTION 1401. Applicability of Article; Company's Option to Effect Defeasance or
Covenant Defeasance.

         If, pursuant to Section 301, provision is made for either or both of
(a) defeasance of the Securities of or within a series under Section 1402 or (b)
covenant defeasance of the Securities of or within a series under Section 1403
to be applicable to the Securities of any series, then the provisions of such
Section or Sections, as the case may be, together with the other provisions of
this Article (with such modifications thereto as may be specified pursuant to
Section 301 with respect to any Securities), shall be applicable to


                                      -64-
<PAGE>   71
such Securities and any coupons appertaining thereto, and the Company may at its
option by Board Resolution at any time, with respect to such Securities and any
coupons appertaining thereto, elect to defease such Outstanding Securities and
any coupons appertaining thereto pursuant to Section 1402 (if applicable) or
Section 1403 (if applicable) upon compliance with the conditions set forth below
in this Article.

SECTION 1402.  Defeasance and Discharge.

         Upon the Company's exercise of the above option applicable to this
Section with respect to any Securities of or within a series, the Company shall
be deemed to have been discharged from its obligations and the provisions of
Article Seventeen shall cease to be effective with respect to such Outstanding
Securities and any coupons appertaining thereto on and after the date the
conditions set forth in Section 1404 are satisfied (hereinafter, "defeasance").
For this purpose, such defeasance means that the Company shall be deemed to have
paid and discharged the entire indebtedness represented by such Outstanding
Securities and any coupons appertaining thereto, which shall thereafter be
deemed to be "Outstanding" only for the purposes of Section 1405 and the other
Sections of this Indenture referred to in clauses (A) and (B) below, and to have
satisfied all of its other obligations under such Securities and any coupons
appertaining thereto and this Indenture insofar as such Securities and any
coupons appertaining thereto are concerned (and the Trustee, at the expense of
the Company, shall execute proper instruments acknowledging the same), except
for the following which shall survive until otherwise terminated or discharged
hereunder: (A) the rights of Holders of such Outstanding Securities and any
coupons appertaining thereto to receive, solely from the trust fund described in
Section 1404 and as more fully set forth in such Section, payments in respect of
the principal of (and premium or Make-Whole Amount, if any) and interest, if
any, on such Securities and any coupons appertaining thereto when such payments
are due, (B) the Company's obligations with respect to such Securities under
Sections 305, 306, 1002 and 1003 and with respect to the payment of Additional
Amounts, if any, on such Securities as contemplated by Section 1011, (C) the
rights, powers, trusts, duties and immunities of the Trustee hereunder and (D)
this Article. Subject to compliance with this Article Fourteen, the Company may
exercise its option under this Section notwithstanding the prior exercise of its
option under Section 1403 with respect to such Securities and any coupons
appertaining thereto.

SECTION 1403.  Covenant Defeasance.

         Upon the Company's exercise of the above option applicable to this
Section with respect to any Securities of or within a series, the Company shall
be released from its obligations under Sections 1005 to 1009, inclusive the
provisions of Article Seventeen shall cease to be effective, and, if specified
pursuant to Section 301, its obligations under any other covenant, with respect
to such Outstanding Securities and any coupons appertaining thereto on and after
the date the conditions set forth in Section 1404 are satisfied (hereinafter,
"covenant defeasance"), and such Securities and any coupons appertaining thereto
shall thereafter be deemed to be not "Outstanding" for the purposes of any
direction, waiver, consent or declaration or Act of Holders (and the
consequences of any thereof) in connection with Sections 1005 to 1009,
inclusive, or such other covenant, but shall continue to be deemed "Outstanding"
for all other purposes hereunder. For this purpose, such covenant defeasance
means that, with respect to such Outstanding Securities and any coupons
appertaining thereto, the Company may omit to comply with and shall have no
liability in respect of any term, condition or limitation set forth in any such
Section, Article Seventeen or such other covenant, whether directly or
indirectly, by reason of any reference elsewhere herein to any such Section or
such other covenant or by reason of reference in any such Section or such other
covenant to any other provision herein or in any other document and such
omission to comply shall not constitute a default or an Event of Default under
Section 501(4) or 501(8) or otherwise, as the case may be, but, except as
specified above, the remainder of this Indenture and such Securities and any
coupons appertaining thereto shall be unaffected thereby.

SECTION 1404.  Conditions to Defeasance or Covenant Defeasance.

         The following shall be the conditions to application of Section 1402 or
Section 1403 to any


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<PAGE>   72
Outstanding Securities of or within a series and any coupons appertaining
thereto:

                  (a) The Company shall irrevocably have deposited or caused to
         be deposited with the Trustee (or another trustee satisfying the
         requirements of Section 607 who shall agree to comply with the
         provisions of this Article Fourteen applicable to it) as trust funds in
         trust for the purpose of making the following payments, specifically
         pledged as security for, and dedicated solely to, the benefit of the
         Holders of such Securities and any coupons appertaining thereto, (1) an
         amount in such currency, currencies or currency unit in which such
         Securities and any coupons appertaining thereto are then specified as
         payable at Stated Maturity, or (2) if Securities of such series are not
         subject to early repayment at the option of the Holders, Government
         Obligations applicable to such Securities and coupons appertaining
         thereto (determined on the basis of the currency, currencies or
         currency unit in which such Securities and coupons appertaining thereto
         are then specified as payable at Stated Maturity) which through the
         scheduled payment of principal and interest in respect thereof in
         accordance with their terms will provide, not later than one day before
         the due date of any payment of principal of (and premium or Make-Whole
         Amount, if any) and interest, if any, and Additional Amounts, if any,
         on such Securities and any coupons appertaining thereto, money in an
         amount, or (3) a combination thereof in an amount, sufficient, without
         consideration of any reinvestment of such principal and interest, in
         the opinion of a nationally recognized firm of independent public
         accountants expressed in a written certification thereof delivered to
         the Trustee, to pay and discharge, and which shall be applied by the
         Trustee (or other qualifying trustee) to pay and discharge, (i) the
         principal of (and premium or Make-Whole Amount, if any) and interest,
         if any, and Additional Amounts, if any, on such Outstanding Securities
         and any coupons appertaining thereto on the Stated Maturity of such
         principal or installment of principal or interest and (ii) any
         mandatory sinking fund payments or analogous payments applicable to
         such Outstanding Securities and any coupons appertaining thereto on the
         day on which such payments are due and payable in accordance with the
         terms of this Indenture and of such Securities and any coupons
         appertaining thereto; provided, that the Trustee shall have been
         irrevocably instructed to apply such money or the proceeds of such
         Government Obligations to said payments with respect to such
         Securities. Before such a deposit, the Company may give to the Trustee,
         in accordance with Section 1102 hereof, a notice of its election to
         redeem all or any portion of such Outstanding Securities at a future
         date in accordance with the terms of the Securities of such series and
         Article Eleven hereof, which notice shall be irrevocable. Such
         irrevocable redemption notice, if given, shall be given effect in
         applying the foregoing.

                  (b) Such defeasance or covenant defeasance shall not result in
         a breach or violation of, or constitute a breach or default under, this
         Indenture or any other material agreement or instrument to which the
         Company is a party or by which it is bound (and shall not cause the
         Trustee to have a conflicting interest pursuant to Section 310(b) of
         the TIA with respect to any Security of the Company).

                  (c) No Event of Default or event which with notice or lapse of
         time or both would become an Event of Default with respect to such
         Securities and any coupons appertaining thereto shall have occurred and
         be continuing on the date of such deposit or, insofar as Sections
         501(6) and 501(7) are concerned, at any time during the period ending
         on the 91st day after the date of such deposit (it being understood
         that this condition shall not be deemed satisfied until the expiration
         of such period).

                  (d) In the case of an election under Section 1402, the Company
         shall have delivered to the Trustee an Opinion of Counsel stating that
         (i) the Company has received from, or there has been published by, the
         Internal Revenue Service a ruling, or (ii) since the date of execution
         of this Indenture, there has been a change in the applicable Federal
         income tax law, in either case to the effect that, and based thereon
         such opinion shall confirm that, the Holders of such Outstanding
         Securities and any coupons appertaining thereto will not recognize
         income, gain or loss for Federal income tax purposes as a result of
         such defeasance and will be subject to Federal income tax on the same
         amounts, in the same manner and at the same times as would have been
         the case if such defeasance had not occurred.


                                      -66-
<PAGE>   73
                  (e) In the case of an election under Section 1403, the Company
         shall have delivered to the Trustee an Opinion of Counsel to the effect
         that the Holders of such Outstanding Securities and any coupons
         appertaining thereto will not recognize income, gain or loss for
         Federal income tax purposes as a result of such covenant defeasance and
         will be subject to Federal income tax on the same amounts, in the same
         manner and at the same times as would have been the case if such
         covenant defeasance had not occurred.

                  (f) The Company shall have delivered to the Trustee an
         Officers' Certificate and an Opinion of Counsel, each stating that all
         conditions precedent to the defeasance under Section 1402 or the
         covenant defeasance under Section 1403 (as the case may be) have been
         complied with and an Opinion of Counsel to the effect that either (i)
         as a result of a deposit pursuant to subsection (a) above and the
         related exercise of the Company's option under Section 1402 or Section
         1403 (as the case may be) registration is not required under the
         Investment Company Act of 1940, as amended, by the Company, with
         respect to the trust funds representing such deposit or by the Trustee
         for such trust funds or (ii) all necessary registrations under said Act
         have been effected.

                  (g) After the 91st day following the deposit, the trust funds
         will not be subject to the effect of any applicable bankruptcy,
         insolvency, reorganization or similar laws affecting creditors' rights
         generally.

                  (h) The Company shall have delivered an Opinion of Counsel to
         the effect that the trust funds deposited pursuant to this Section will
         not be subject to the rights of any holders of Senior Debt, including
         those arising under Article Seventeen, except and subject to the effect
         of any applicable bankruptcy, insolvency, reorganization or similar
         laws affecting creditors' rights generally and general principals of
         equity.

                  (i) Notwithstanding any other provisions of this Section, such
         defeasance or covenant defeasance shall be effected in compliance with
         any additional or substitute terms, conditions or limitations which may
         be imposed on the Company in connection therewith pursuant to Section
         301.

SECTION 1405. Deposited Money and Government Obligations to Be Held in Trust;
Other Miscellaneous Provisions.

         Subject to the provisions of the last paragraph of Section 1003, all
money and Government Obligations (or other property as may be provided pursuant
to Section 301) (including the proceeds thereof) deposited with the Trustee (or
other qualifying trustee, collectively for purposes of this Section 1405, the
"Trustee") pursuant to Section 1404 in respect of any Outstanding Securities of
any series and any coupons appertaining thereto shall be held in trust and
applied by the Trustee, in accordance with the provisions of such Securities and
any coupons appertaining thereto and this Indenture, to the payment, either
directly or through any Paying Agent (including the Company acting as its own
Paying Agent) as the Trustee may determine, to the Holders of such Securities
and any coupons appertaining thereto of all sums due and to become due thereon
in respect of principal (and premium or Make-Whole Amount, if any) and interest
and Additional Amounts, if any, but such money need not be segregated from other
funds except to the extent required by law.

         Money and Government Obligations (including the proceeds thereof) so
held in trust shall not be subject to the provisions of Article Seventeen,
provided that the applicable conditions of Section 1404 have been satisfied.

         Unless otherwise specified with respect to any Security pursuant to
Section 301, if, after a deposit referred to in Section 1404(a) has been made,
(a) the Holder of a Security in respect of which such deposit was made is
entitled to, and does, elect pursuant to Section 301 or the terms of such
Security to receive payment in a currency or currency unit other than that in
which the deposit pursuant to Section 1404(a) has


                                      -67-
<PAGE>   74
been made in respect of such Security, or (b) a Conversion Event occurs in
respect of the currency or currency unit in which the deposit pursuant to
Section 1404(a) has been made, the indebtedness represented by such Security and
any coupons appertaining thereto shall be deemed to have been, and will be,
fully discharged and satisfied through the payment of the principal of (and
premium or Make-Whole Amount, if any), and interest, if any, on such Security as
the same becomes due out of the proceeds yielded by converting (from time to
time as specified below in the case of any such election) the amount or other
property deposited in respect of such Security into the currency or currency
unit in which such Security becomes payable as a result of such election or
Conversion Event based on the applicable market exchange rate for such currency
or currency unit in effect on the second Business Day prior to each payment
date, except, with respect to a Conversion Event, for such currency or currency
unit in effect (as nearly as feasible) at the time of the Conversion Event.

         The Company shall pay and indemnify the Trustee against any tax, fee or
other charge imposed on or assessed against the Government Obligations deposited
pursuant to Section 1404 or the principal and interest received in respect
thereof other than any such tax, fee or other charge which by law is for the
account of the Holders of such Outstanding Securities and any coupons
appertaining thereto.

         Anything in this Article to the contrary notwithstanding, the Trustee
shall deliver or pay to the Company from time to time upon Company Request any
money or Government Obligations (or other property and any proceeds therefrom)
held by it as provided in Section 1404 which, in the opinion of a nationally
recognized firm of independent public accountants expressed in a written
certification thereof delivered to the Trustee, are in excess of the amount
thereof which would then be required to be deposited to effect a defeasance or
covenant defeasance, as applicable, in accordance with this Article.

SECTION 1406.  Reinstatement.

         If the Trustee or the Paying Agent is unable to apply any money or the
Government Obligations, as the case may be, in accordance with this Article with
respect to any Securities by reason of any order or judgment of any court or
governmental authority enjoining, restraining or otherwise prohibiting such
application, then the obligations under this Indenture, such Securities and any
coupons appertaining thereto from which the Company has been discharged or
released pursuant to Section 1402 or 1403 shall be revived and reinstated as
though no deposit had occurred pursuant to this Article with respect to such
Securities, until such time as the Trustee or Paying Agent is permitted to apply
all money or Government Obligations, as the case may be, held in trust pursuant
to Section 1405 with respect to such Securities and any coupons appertaining
thereto in accordance with this Article; provided, however, that if the Company
makes any payment of principal of or any premium or interest on any such
Security following such reinstatement of its obligations, the Company shall be
subrogated to the rights (if any) of the Holders of such Securities or coupons
to receive such payment from the money or Government Obligations, as the case
may be, so held in trust.

                                 ARTICLE FIFTEEN
                        MEETINGS OF HOLDERS OF SECURITIES

SECTION 1501.  Purposes for Which Meetings May Be Called.

         A meeting of Holders of Securities of any series may be called at any
time and from time to time pursuant to this Article to make, give or take any
request, demand, authorization, direction, notice, consent, waiver or other
action provided by this Indenture to be made, given or taken by Holders of
Securities of such series.

SECTION 1502.  Call, Notice and Place of Meetings.

         (a) The Trustee may at any time call a meeting of Holders of Securities
of any series for any purpose specified in Section 1501, to be held at such time
and at such place in the City of Birmingham, Alabama or the Borough of
Manhattan, The City of New York, or in London as the Trustee shall determine.
Notice of every meeting of Holders of Securities of any series, setting forth
the time and the


                                      -68-
<PAGE>   75
place of such meeting and in general terms the action proposed to be taken at
such meeting, shall be given, in the manner provided in Section 106, not less
than 21 nor more than 180 days prior to the date fixed for the meeting.

         (b) In case at any time the Company, pursuant to a Board Resolution, or
the Holders of at least 10% in principal amount of the Outstanding Securities of
any series shall have requested the Trustee to call a meeting of the Holders of
Securities of such series for any purpose specified in Section 1501, by written
request setting forth in reasonable detail the action proposed to be taken at
the meeting, and the Trustee shall not have made the first publication of the
notice of such meeting within 21 days after receipt of such request or shall not
thereafter proceed to cause the meeting to be held as provided herein, then the
Company or the Holders of Securities of such series in the amount above
specified, as the case may be, may determine the time and the place in the City
of Birmingham, Alabama or the Borough of Manhattan, The City of New York, or in
London for such meeting and may call such meeting for such purposes by giving
notice thereof as provided in subsection (a) of this Section.

SECTION 1503.  Persons Entitled to Vote at Meetings.

         To be entitled to vote at any meeting of Holders of Securities of any
series, a Person shall be (1) a Holder of one or more Outstanding Securities of
such series, or (2) a Person appointed by an instrument in writing as proxy for
a Holder or Holders of one or more Outstanding Securities of such series by such
Holder or Holders. The only Persons who shall be entitled to be present or to
speak at any meeting of Holders of Securities of any series shall be the Persons
entitled to vote at such meeting and their counsel, any representatives of the
Trustee and its counsel and any representatives of the Company and its counsel.

SECTION 1504.  Quorum; Action.

         The Persons entitled to vote a majority in principal amount of the
Outstanding Securities of a series shall constitute a quorum for a meeting of
Holders of Securities of such series; provided, however, that if any action is
to be taken at such meeting with respect to a consent or waiver which this
Indenture expressly provides may be given by the Holders of not less than a
specified percentage in principal amount of the Outstanding Securities of a
series, the Persons entitled to vote such specified percentage in principal
amount of the Outstanding Securities of such series shall constitute a quorum.
In the absence of a quorum within 30 minutes after the time appointed for any
such meeting, the meeting shall, if convened at the request of Holders of
Securities of such series, be dissolved. In any other case the meeting may be
adjourned for a period of not less than 10 days as determined by the chairman of
the meeting prior to the adjournment of such meeting. In the absence of a quorum
at any such adjourned meeting, such adjourned meeting may be further adjourned
for a period of not less than 10 days as determined by the chairman of the
meeting prior to the adjournment of such adjourned meeting. Notice of the
reconvening of any adjourned meeting shall be given as provided in Section
1502(a), except that such notice need be given only once not less than five (5)
days prior to the date on which the meeting is scheduled to be reconvened.
Notice of the reconvening of any adjourned meeting shall state expressly the
percentage, as provided above, of the principal amount of the Outstanding
Securities of such series which shall constitute a quorum. Except as limited by
the proviso to Section 902, any resolution presented to a meeting or adjourned
meeting duly reconvened at which a quorum is present as aforesaid may be adopted
by the affirmative vote of the Holders of a majority in principal amount of the
Outstanding Securities of that series; provided, however, that, except as
limited by the proviso to Section 902, any resolution with respect to any
request, demand, authorization, direction, notice, consent, waiver or other
action which this Indenture expressly provides may be made, given or taken by
the Holders of a specified percentage, which is less than a majority, in
principal amount of the Outstanding Securities of a series may be adopted at a
meeting or an adjourned meeting duly reconvened and at which a quorum is present
as aforesaid by the affirmative vote of the Holders of such specified percentage
in principal amount of the Outstanding Securities of that series.

         Any resolution passed or decision taken at any meeting of Holders of
Securities of any series duly held in accordance with this Section shall be
binding on all the Holders of Securities of such series and the related coupons,
whether or not present or represented at the meeting.


                                      -69-
<PAGE>   76

         Notwithstanding the foregoing provisions of this Section 1504, if any
action is to be taken at a meeting of Holders of Securities of any series with
respect to any request, demand, authorization, direction, notice, consent,
waiver or other action that this Indenture expressly provides may be made, given
or taken by the Holders of a specified percentage in principal amount of all
Outstanding Securities affected thereby, or of the Holders of such series and
one or more additional series:

                  (i) there shall be no minimum quorum requirement for such
         meeting; and

                  (ii) the principal amount of the Outstanding Securities of
         such series that vote in favor of such request, demand, authorization,
         direction, notice, consent, waiver or other action shall be taken into
         account in determining whether such request, demand, authorization,
         direction, notice, consent, waiver or other action has been made, given
         or taken under this Indenture.

SECTION 1505. Determination of Voting Rights; Conduct and Adjournment of
Meetings.

         (a) Notwithstanding any provisions of this Indenture, the Trustee may
make such reasonable regulations as it may deem advisable for any meeting of
Holders of Securities of a series in regard to proof of the holding of
Securities of such series and of the appointment of proxies and in regard to the
appointment and duties of inspectors of votes, the submission and examination of
proxies, certificates and other evidence of the right to vote, and such other
matters concerning the conduct of the meeting as it shall deem appropriate.
Except as otherwise permitted or required by any such regulations, the holding
of Securities shall be proved in the manner specified in Section 104 and the
appointment of any proxy shall be proved in the manner specified in Section 104
or by having the signature of the Person executing the proxy witnessed or
guaranteed by any trust company, bank or banker authorized by Section 104 to
certify to the holding of Bearer Securities. Such regulations may provide that
written instruments appointing proxies, regular on their face, may be presumed
valid and genuine without the proof specified in Section 104 or other proof.

         (b) The Trustee shall, by an instrument in writing, appoint a temporary
chairman of the meeting, unless the meeting shall have been called by the
Company or by Holders of Securities as provided in Section 1502(b), in which
case the Company or the Holders of Securities of or within the series calling
the meeting, as the case may be, shall in like manner appoint a temporary
chairman. A permanent chairman and a permanent secretary of the meeting shall be
elected by vote of the Persons entitled to vote a majority in principal amount
of the Outstanding Securities of such series represented at the meeting.

         (c) At any meeting each Holder of a Security of such series or proxy
shall be entitled to one vote for each $1,000 principal amount of the
Outstanding Securities of such series held or represented by him; provided,
however, that no vote shall be cast or counted at any meeting in respect of any
Security challenged as not Outstanding and ruled by the chairman of the meeting
to be not Outstanding. The chairman of the meeting shall have no right to vote,
except as a Holder of a Security of such series or proxy.

         (d) Any meeting of Holders of Securities of any series duly called
pursuant to Section 1502 at which a quorum is present may be adjourned from time
to time by Persons entitled to vote a majority in principal amount of the
Outstanding Securities of such series represented at the meeting, and the
meeting may be held as so adjourned without further notice.

SECTION 1506.  Counting Votes and Recording Action of Meetings.

The vote upon any resolution submitted to any meeting of Holders of Securities
of any series shall be by written ballots on which shall be subscribed the
signatures of the Holders of Securities of such series or of their
representatives by proxy and the principal amounts and serial numbers of the
Outstanding Securities of such series held or represented by them. The permanent
chairman of the meeting shall appoint two inspectors of votes who shall count
all votes cast at the meeting for or against any resolution and who shall make
and file with the secretary of the meeting their verified written reports in
duplicate of all votes cast at the meeting. A record, at least in duplicate, of
the proceedings of each meeting of Holders of


                                      -70-
<PAGE>   77
Securities of any series shall be prepared by the secretary of the meeting and
there shall be attached to said record the original reports of the inspectors of
votes on any vote by ballot taken thereat and affidavits by one or more persons
having knowledge of the fact, setting forth a copy of the notice of the meeting
and showing that said notice was given as provided in Section 1502 and, if
applicable, Section 1504. Each copy shall be signed and verified by the
affidavits of the permanent chairman and secretary of the meeting and one such
copy shall be delivered to the Company and another to the Trustee to be
preserved by the Trustee, the latter to have attached thereto the ballots voted
at the meeting. Any record so signed and verified shall be conclusive evidence
of the matters therein stated.

SECTION 1507.  Evidence of Action Taken by Holders.

         Any request, demand, authorization, direction, notice, consent, waiver
or other action provided by this Indenture to be given or taken by a specified
percentage in principal amount of the Holders of any or all series may be
embodied in and evidenced by one or more instruments of substantially similar
tenor signed by such specified percentage of Holders in person or by agent duly
appointed in writing; and, except as herein otherwise expressly provided, such
action shall become effective when such instrument or instruments are delivered
to the Trustee. Proof of execution of any instrument or of a writing appointing
any such agent shall be sufficient for any purpose of this Indenture and
(subject to Sections 315(a) through 315(d) of the TIA) conclusive in favor of
the Trustee and the Company, if made in the manner provided in this Article.

SECTION 1508.  Proof of Execution of Instruments.

         Subject to TIA Sections 315(a) through 315(d), the execution of any
instrument by a Holder or his agent or proxy may be proved in accordance with
such reasonable rules and regulations as may be prescribed by the Trustee or in
such manner as shall be satisfactory to the Trustee.

                                 ARTICLE SIXTEEN
                      CONVERSION OR EXCHANGE OF SECURITIES

SECTION 1601.  Applicability of Article.

         The provisions of this Article shall be applicable to the Securities of
any series which are convertible or exchangeable for other securities or
property (including securities of other issuers, provided that such securities
are registered under Section 12 of the Exchange Act and such issuer is then
eligible to use Form S-3 (or any successor form) for a primary offering of its
securities) of the Company, except as otherwise specified as contemplated by
Section 301 for the Securities of such series.

SECTION 1602.  Election to Exchange; Notice to Trustee and Holders.

         The election of the Company to exchange any Securities shall be
evidenced by a Board Resolution or in another manner specified as contemplated
by Section 301 for such Securities. On or prior to the seventh Business Day
prior to Maturity of the Securities, the Company shall provide written notice to
the Holders of record of the Securities and to the Trustee and will publish a
notice in a daily newspaper of national circulation stating whether the Company
has made such election.

SECTION 1603.  No Fractional Shares.

         No fractional shares of securities shall be delivered upon exchanges of
Securities of any series. If more than one Security shall be surrendered for
exchange at one time by the same Holder, the number of full shares which shall
be delivered upon exchange shall be computed on the basis of the aggregate
principal amount of the Securities (or specified portions thereof to the extent
permitted hereby) so surrendered. If, except for the provisions of this Section
1603, any Holder of a Security or Securities would be entitled to a fractional
share of a security upon the exchange of such Security or Securities, or
specified portions thereof, the Company shall pay to such Holder an amount in
cash equal to the current market value of such fractional share computed on the
basis of an average Closing Price of such security. The "Closing


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<PAGE>   78
Price" of any security on any date of determination means, (i) if such security
is listed or admitted to unlisted trading privileges on a national securities
exchange, the last reported sale price regular way on such exchange, (ii) if
such security is not at the time so listed, as reported by the NASDAQ National
Market, or (iii) if such security is not at the time so listed or reported or
admitted to unlisted trading privileges on a national securities exchange, the
average of the bid and asked prices of such security in the over-the-counter
market, as reported by the National Quotation Bureau, Incorporated or similar
organization if the National Quotation Bureau, Incorporated is no longer
reporting such information, or if not so available, the market price as
determined by a nationally recognized independent investment banking firm
retained for this purpose by the Company.

SECTION 1604.  Adjustment of Exchange Rate.

         The exchange rate of Securities of any series that is exchangeable for
other securities or property (including securities of other issuers, provided
that such securities are registered under Section 12 of the Exchange Act and
such issuer is then eligible to use Form S-3 (or any successor form) for a
primary offering of its securities) of the Company shall be adjusted for any
stock dividends, stock splits, reclassification, combinations or similar
transactions or any consolidation, merger or other reorganization event in
accordance with the terms of the supplemental indenture or Board Resolution
setting forth the terms of the Securities of such series.

         Whenever the exchange rate is adjusted, the Company shall compute the
adjusted exchange rate in accordance with terms of the applicable Board
Resolution or supplemental indenture and shall prepare an Officers' Certificate
setting forth the adjusted exchange rate and showing in reasonable detail the
facts upon which such adjustment is based, and such certificate shall forthwith
be filed at each office or agency maintained for the purpose of exchange of
Securities pursuant to Section 1002 and, if different, with the Trustee. The
Company shall forthwith cause a notice setting forth the adjusted exchange rate
to be mailed, first class postage prepaid, to each Holder of Securities of such
series at its address appearing on the Security Register and to any exchange
agent other than the Trustee.

SECTION 1605.  Payment of Certain Taxes Upon Exchange.

         The Company will pay any and all taxes that may be payable in respect
of the transfer and delivery of shares of other securities or property
(including securities of other issuers, provided that such securities are
registered under Section 12 of the Exchange Act and such issuer is then eligible
to use Form S-3 (or any successor form) for a primary offering of its
securities) of the Company on exchange of Securities pursuant hereto. The
Company shall not, however, be required to pay any tax which may be payable in
respect of any transfer involved in the delivery of shares of securities in a
name other than that of the Holder of the Security or Securities to be
exchanged, and no such transfer or delivery shall be made unless and until the
person requesting such transfer has paid to the Company the amount of any such
tax, or has established, to the satisfaction of the Company, that such tax has
been paid.

SECTION 1606.  Shares Free and Clear.

         The Company hereby warrants that upon exchange of Securities of any
series, the Holder of a Security shall receive all rights held by the Company in
such security for which such Security is at such time exchangeable under this
Article Sixteen, free and clear of any and all liens, claims, charges and
encumbrances other, to the extent permitted by the terms of the Securities of
such series, than any liens, claims, charges and encumbrances which may have
been placed on any such security by the prior owner thereof, prior to the time
such security was acquired by the Company. Except as provided in Section 1604,
the Company will pay all taxes and charges with respect to the delivery of such
security delivered in exchange for Securities hereunder.

SECTION 1607.  Cancellation of Security.

Upon receipt by the Trustee of Securities of any series delivered to it for
exchange under this Article Sixteen, the Trustee shall cancel and dispose of the
same as provided in Section 309.


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<PAGE>   79
SECTION 1608.  Duties of Trustee Regarding Exchange.

         Neither the Trustee nor any exchange agent shall at any time be under
any duty or responsibility to any Holder of Securities of any series that is
exchangeable into other securities or property (including securities of other
issuers, provided that such securities are registered under Section 12 of the
Exchange Act and such issuer is then eligible to use Form S-3 (or any successor
form) for a primary offering of its securities) of the Company to determine
whether any facts exist which may require any adjustment of the exchange rate,
or with respect to the nature or extent of any such adjustment when made, or
with respect to the method employed, whether herein or in any supplemental
indenture, any resolutions of the Board of Directors or written instrument
executed by one or more officers of the Company provided to be employed in
making the same. Neither the Trustee nor any exchange agent shall be accountable
with respect to the validity or value (or the kind or amount) of any securities
or property (including securities of other issuers, provided that such
securities are registered under Section 12 of the Exchange Act and such issuer
is then eligible to use Form S-3 (or any successor form) for a primary offering
of its securities) of the Company, or of any Securities and neither the Trustee
nor any exchange agent makes any representation with respect thereto. Subject to
the provisions of Section 612, neither the Trustee nor any exchange agent shall
be responsible for any failure of the Company to issue, transfer or deliver any
stock certificates or other securities or property (including securities of
other issuers, provided that such securities are registered under Section 12 of
the Exchange Act and such issuer is then eligible to use Form S-3 (or any
successor form) for a primary offering of its securities) upon the surrender of
any Security for the purpose of exchange or to comply with any of the covenants
of the Company contained in this Article Sixteen or in the applicable
supplemental indenture, resolutions of the Board of Directors or written
instrument executed by one or more duly authorized officers of the Company.

SECTION 1609.  Repayment of Certain Funds Upon Exchange.

         Any funds which at any time shall have been deposited by the Company or
on its behalf with the Trustee or any other paying agent for the purpose of
paying the principal of, and premium, if any, and interest, if any, on any of
the Securities (including funds deposited for the sinking fund referred to in
Article Twelve hereof) and which shall not be required for such purposes because
of the exchange of such Securities as provided in this Article Sixteen shall
after such exchange be repaid to the Company by the Trustee upon the Company's
written request.

SECTION 1610.  Exercise of Conversion Privilege.

         In order to exercise a conversion or exchange privilege, the Holder of
a Security of a series with such a privilege shall surrender such Security to
the Company at the office or agency maintained for that purpose pursuant to
Section 1002, accompanied by written notice to the Company that the Holder
elects to convert or exchange such Security or a specified portion thereof. Such
notice shall also state, if different from the name or names (with address) in
which the Securities are registered, the name or names in which the securities
or property (including securities of other issuers, provided that such
securities are registered under Section 12 of the Exchange Act and such issuer
is then eligible to use Form S-3 (or any successor form) for a primary offering
of its securities) of the Company which shall be issuable on such conversion or
exchange shall be issued. Securities surrendered for conversion or exchange
shall (if so required by the Company or the Trustee) be duly endorsed by or
accompanied by instruments of transfer in forms satisfactory to the Company and
the Trustee duly executed by the registered Holder or its attorney duly
authorized in writing; and Securities so surrendered for conversion or exchange
during the period from the close of business on any Regular Record Date to the
opening of business on the next succeeding Interest Payment Date (excluding
Securities or portions thereof called for redemption during such period) shall
also be accompanied by payment in funds acceptable to the Company of an amount
equal to the interest payable on such Interest Payment Date on the principal
amount of such Security then being converted, and such interest shall be payable
to such registered Holder notwithstanding the conversion or exchange of such
Security, subject to the provisions of Section 307 relating to the payment of
Defaulted Interest by the Company. As promptly as practicable after the receipt
of such notice and of any payment required pursuant to a Board Resolution and,
subject to Section 303, set forth, or determined in the manner provided, in an


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<PAGE>   80
Officers' Certificate, or established in one or more indentures supplemental
hereto setting forth the terms of such series of Security, and the surrender of
such Security in accordance with such reasonable regulations as the Company may
prescribe, the Company shall issue and shall deliver, at the office or agency at
which such Security is surrendered, to such Holder or on its written order,
securities or property (including securities of other issuers, provided that
such securities are registered under Section 12 of the Exchange Act and such
issuer is then eligible to use Form S-3 (or any successor form) for a primary
offering of its securities) of the Company issuable or deliverable upon the
conversion or exchange of such Security (or specified portion thereof), in
accordance with the provisions of such Board Resolution, Officers' Certificate
or supplemental indenture, and cash as provided therein in respect of any
fractional share of such common stock otherwise issuable upon such conversion or
exchange. Such conversion or exchange shall be deemed to have been effected
immediately prior to the close of business on the date on which such notice and
such payment, if required, shall have been received in proper order for
conversion or exchange by the Company and such Security shall have been
surrendered as aforesaid (unless such Holder shall have so surrendered such
Security and shall have instructed the Company to effect the conversion or
exchange on a particular date following such surrender and such Holder shall be
entitled to convert or exchange such Security on such date, in which case such
conversion or exchange shall be deemed to be effected immediately prior to the
close of business on such date) and at such time the rights of the Holder of
such Security as such Security Holder shall cease and the person or persons in
whose name or names any securities or property (including securities of other
issuers, provided that such securities are registered under Section 12 of the
Exchange Act and such issuer is then eligible to use Form S-3 (or any successor
form) for a primary offering of its securities) of the Company shall be issuable
or deliverable upon such conversion or exchange shall be deemed to have become
the Holder or Holders of record of the shares represented thereby. Except as set
forth above and subject to the final paragraph of Section 307, no payment or
adjustment shall be made upon any conversion or exchange on account of any
interest accrued on the Securities surrendered for conversion or exchange or on
account of any interest or dividends on the securities or property (including
securities of other issuers, provided that such securities are registered under
Section 12 of the Exchange Act and such issuer is then eligible to use Form S-3
(or any successor form) for a primary offering of its securities) of the Company
issued or delivered upon such conversion or exchange.

         In the case of any Security which is converted or exchanged in part
only, upon such conversion or exchange the Company shall execute and the Trustee
shall authenticate and deliver to or on the order of the Holder thereof, at the
expense of the Company, a new Security or Securities of the same series, of
authorized denominations, in aggregate principal amount equal to the unconverted
or unexchanged portion of such Security.

SECTION 1611.  Effect of Consolidation or Merger on Conversion Privilege.

         In case of any consolidation of the Company with, or merger of the
Company into or with any other Person, or in case of any sale of all or
substantially all of the assets of the Company, the Company or the Person formed
by such consolidation or the Person into which the Company shall have been
merged or the Person which shall have acquired such assets, as the case may be,
shall execute and deliver to the Trustee a supplemental indenture providing that
the Holder of each Security then outstanding of any series that is convertible
into common stock of the Company shall have the right, which right shall be the
exclusive conversion right thereafter available to said Holder (until the
expiration of the conversion right of such Security), to convert such Security
into the kind and amount of shares of stock or other securities or property
(including cash) receivable upon such consolidation, merger or sale by a holder
of the number of shares of common stock of the Company into which such Security
might have been converted immediately prior to such consolidation, merger or
sale, subject to compliance with the other provisions of this Indenture, such
Security and such supplemental indenture. Such supplemental indenture shall
provide for adjustments which shall be as nearly equivalent as may be
practicable to the adjustments provided for in such Security. The above
provisions of this Section shall similarly apply to successive consolidations,
mergers or sales. It is expressly agreed and understood that anything in this
Indenture to the contrary notwithstanding, if, pursuant to such merger,
consolidation or sale, holders of outstanding shares of common stock of the
Company do not receive shares of common stock of the surviving corporation but
receive other securities, cash or other property or any combination thereof,
Holders of Securities shall not


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<PAGE>   81

have the right to thereafter convert their Securities into common stock of the
surviving corporation or the corporation which shall have acquired such assets,
but rather, shall have the right upon such conversion to receive the other
securities, cash or other property receivable by a holder of the number of
shares of common stock of the Company into which the Securities held by such
holder might have been converted immediately prior to such consolidation, merger
or sale, all as more fully provided in the first sentence of this Section 1611.
Anything in this Section 1611 to the contrary notwithstanding, the provisions of
this Section 1611 shall not apply to a merger or consolidation of another
corporation with or into the Company pursuant to which both of the following
conditions are applicable: (i) the Company is the surviving corporation and (ii)
the outstanding shares of common stock of the Company are not changed or
converted into any other securities or property (including cash) or changed in
number or character or reclassified pursuant to the terms of such merger or
consolidation.

         As evidence of the kind and amount of shares of stock or other
securities or property (including cash) into which Securities may properly be
convertible after any such consolidation, merger or sale, or as to the
appropriate adjustments of the conversion prices applicable with respect
thereto, the Trustee shall be furnished with and may accept the certificate or
opinion of an independent certified public accountant with respect thereto; and,
in the absence of bad faith on the part of the Trustee, the Trustee may
conclusively rely thereon, and shall not be responsible or accountable to any
Holder of Securities for any provision in conformity therewith or approved by
such independent certified accountant which may be contained in said
supplemental indenture.

                                ARTICLE SEVENTEEN
                                  SUBORDINATION

SECTION 1701.  Agreement to Subordinate.

         Except as otherwise provided in a supplemental indenture or pursuant to
Section 301, the Company agrees, and each Holder by accepting a Security agrees,
that the indebtedness evidenced by the Securities is subordinated in right of
payment, to the extent and in the manner provided in this Article, to the prior
payment in full of all Senior Debt and that the subordination is for the benefit
of the holders of Senior Debt.

         Notwithstanding the foregoing, if a deposit referred to in Section
1404(a) is made pursuant to Section 1402 or Section 1403 with respect to any
Securities (and provided all other conditions set out in Section 1402 or 1403,
as applicable, shall have been satisfied with respect to such Securities), then,
when the 90/th/day after such deposit has ended, no money or Government
Obligations so deposited, and no proceeds thereon, will be subject to any rights
of holders of Senior Debt, including any such rights arising under this Article
Seventeen.

SECTION 1702.  Liquidation; Dissolution; Bankruptcy.

         In the event of (a) any insolvency or bankruptcy case or proceeding, or
any receivership, liquidation, reorganization or other similar case or
proceeding in connection therewith, relative to the Company or to its creditors,
as such, or to its assets, or (b) any liquidation, dissolution or other winding
up of the Company, whether voluntary or involuntary and whether or not involving
insolvency or bankruptcy, or (c) any assignment for the benefit of creditors or
any other marshalling of assets and liabilities of the Company:

         (1) holders of Senior Debt shall be entitled to receive payment in full
in cash of the principal thereof, premium, if any, Additional Amounts, if any,
and interest (including interest accruing after the commencement of any such
proceeding) to the date of payment on the Senior Debt before Holders shall be
entitled to receive any payment of principal of or interest on Securities;

         (2) until the Senior Debt is paid in full in cash, any distribution to
which Holders or the Trustee would be entitled but for this Article shall be
made to holders of Senior Debt as their interests may appear


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<PAGE>   82
for the application to the payment thereof, except that Holders may receive
securities that are subordinated to Senior Debt to at least the same extent as
the Securities; and

         (3) the Trustee is entitled to conclusively rely upon an order or
decree of a court of competent jurisdiction or a certificate of a bankruptcy
trustee or other similar official for the purpose of ascertaining the persons
entitled to participate in such distribution, the holders of Senior Debt and
other Company debt, the amount thereof or payable thereon and all other
pertinent facts relating to the Trustee's obligations under this Article
Seventeen.

         In the event that, notwithstanding the foregoing provisions of this
Section, the Trustee or the Holder of any Security shall have received any
payment or distribution of assets of the Company of any kind or character,
whether in cash, property or securities, including any such payment or
distribution which may be payable or deliverable by reason of the payment of any
other indebtedness of the Company being subordinated to the payment of the
Securities, before all Senior Debt is paid in full or payment thereof provided
for, and if such fact shall, at or prior to the time of such payment or
distribution, have been made known to a Responsible Officer of the Trustee in
writing or, as the case may be, such Holder, then and in such event such payment
or distribution shall be paid over or delivered forthwith to the trustee in
bankruptcy, receiver, liquidating trustee, custodian, assignee, agent or other
Person making payment or distribution of assets of the Company for application
to the payment of all Senior Debt remaining unpaid, to the extent necessary to
pay all Senior Debt in full, after giving effect to any concurrent payment or
distribution to or for the holders of Senior Debt. Any taxes that have been
withheld or deducted from any payment or distribution in respect of the
Securities, or any taxes that ought to have been withheld or deducted from any
such payment or distribution that have been remitted to the relevant taxing
authority, shall not be considered to be an amount that the Trustee or the
Holder of any Security receives for purposes of this Section.

SECTION 1703.  Default on Senior Debt.

         The Company may not pay principal, premium, interest or Additional
Amounts on the Securities and may not acquire any Securities for cash or
property other than capital stock of the Company if:

         (1) (a) in the event and during the continuation of any default in the
payment of principal, premium, if any, or interest on any Senior Debt beyond any
applicable grace period with respect thereto or (b) a default on Senior Debt
occurs and is continuing that permits holders of such Senior Debt (or a trustee
on their behalf) to accelerate its maturity, or

         (2) the default is the subject of judicial proceedings or the Company
receives a notice of the default from a person who may give it pursuant to
Section 1711. If the Company receives any such notice, a similar notice received
within nine months thereafter relating to the same default on the same issue of
Senior Debt shall not be effective for purposes of this Section.

         The Company may resume payments on the Securities and may acquire them
when:

                  (a)  the default is cured or waived, or

                  (b) 120 days pass after the notice is given if the default is
         not the subject of judicial proceedings.

                  (c)  if this Article otherwise permits the payment or
         acquisition at that time.

SECTION 1704.  Acceleration of Securities.

         In the event that any Securities are declared due and payable before
their Stated Maturity, then and in such event the holders of Senior Debt shall
be entitled to receive payment in full of all amounts due or to become due on or
in respect of all Senior Debt or provision shall be made for such payment in
cash, before the Holders of the Securities are entitled to receive any payment
(including any payment which may be


                                      -76-
<PAGE>   83
payable by reason of the payment of any other indebtedness of the Company being
subordinated to the payment of the Securities) by the Company on account of the
principal of, premium, if any, Additional Amounts, if any or interest on the
Securities or on account of the purchase or other acquisition of Securities;
provided, however, that nothing in this Section shall prevent the satisfaction
of any sinking fund payment in accordance with Article Twelve by delivering and
crediting pursuant to Section 1202 Securities which have been acquired (upon
redemption or otherwise) prior to such declaration of acceleration; provided,
further, money deposited pursuant to Section 402 not in violation of this
Indenture shall not be subject to the claims of holders of Senior Debt.

         In the event that, notwithstanding the forgoing, the Company shall make
any payment to the Trustee or the Holder of any Security prohibited by the
foregoing provisions of this Section, and if such fact shall, at or prior to the
time of such payment, have been made known to a Responsible Officer of the
Trustee in writing or, as the case may be, such Holder, then and in such event
such payment shall be paid over and delivered forthwith to the Company.

SECTION 1705.  When Distribution Must Be Paid Over.

         If payment or distribution on account of the Securities of any
character or security, whether in cash, securities or other property, is
received by Holder, including any applicable Trustee, in contravention of any of
the terms of this Article and before all Senior Debt has been paid in full, such
payment or distribution or security will be received in trust for the benefit
of, and must be paid over or delivered and transferred to, holders of Senior
Debt at the time outstanding in accordance with the priorities then existing
among those holders of Senior for application to the payment of all Senior Debt
remaining unpaid to the extent necessary to pay all Senior Debt in full.

SECTION 1706.  Notice by Company.

         The Company shall promptly notify the Trustee, in writing, and any
Paying Agent of any facts known to the Company that would cause a payment on the
Securities to violate this Article.

SECTION 1707.  Subrogation.

         After all Senior Debt is paid in full and until the Securities are paid
in full, Holders shall be subrogated to the rights of holders of Senior Debt to
receive payments or distributions applicable to Senior Debt to the extent that
distributions otherwise payable to the Holders have been applied to the payment
of Senior Debt. A payment or distribution made under this Article to holders of
Senior Debt which otherwise would have been made to Holders is not, as among the
Company, its creditors other than the holders of Senior Debt and Holders, a
payment or distribution by the Company on account of the Senior Debt.

SECTION 1708.  Relative Rights.

         This Article is intended solely to define the relative rights of
Holders on the one hand and the holders of Senior Debt on the other hand.
Nothing in this Indenture or in the Securities shall:

         (1) impair, as among the Company, its creditors other than holders of
Senior Debt and the Holders of the Securities, the obligation of the Company,
which is absolute and unconditional, to pay to the Holders of the Securities the
principal of, premium, if any, Additional Amounts, if any, and interest on the
Securities as and when the same shall become due and payable in accordance with
their terms;

         (2) affect the relative rights of Holders and creditors of the Company
other than holders of Senior Debt; or

         (3) prevent the Trustee or any Holder (or to the extent expressly
provided herein, the holder of any Preferred Security) from exercising its
available remedies upon an Event of Default, subject to the rights of holders of
Senior Debt to receive payments or distributions otherwise payable to Holders or
the Trustee.


                                      -77-
<PAGE>   84
         If the Company fails because of this Article to pay principal, premium,
if any, Additional Amounts, if any, or interest on a Security on the due date,
such failure shall constitute a default hereunder.

SECTION 1709.  Subordination May Not Be Impaired By Company.

         No right of any holder of Senior Debt to enforce the subordination of
the indebtedness evidenced by the Securities shall be impaired by any act or
failure to act by the Company or by its failure to comply with this Indenture.

SECTION 1710.  Distribution or Notice to Representative.

         Whenever a distribution is to be made or a notice given to holders of
Senior Debt, the distribution may be made and the notice given to their
Representative.

SECTION 1711.  Rights of Trustee and Paying Agent.

         The Trustee or any Paying Agent may continue to make payments on the
Securities until it receives written notice of facts that would cause a payment
of principal of or interest on the Securities to violate this Article. Only the
Company, a Representative or a holder of an issue of Senior Debt that has no
Representative may give the written notice.

         The Trustee has no fiduciary duty to the holders of Senior Debt other
than as created under this Indenture. The Trustee in its individual or any other
capacity may hold Senior Debt with the same rights it would have if it were not
Trustee.

         The Company's obligation to pay, and the Company's payment of, the
amounts required by Section 606 are excluded from the operation of this Article
Seventeen.

SECTION 1712.  Payment Permitted in Certain Situations.

         Nothing contained in this Article or elsewhere in this Indenture or in
any of the Securities shall prevent (a) the Company, at any time except during
the pendency of any case, proceeding, dissolution, liquidation or other winding
up, assignment for the benefit of creditors or other marshalling of assets and
liabilities of the Company referred to in Section 1702 or under the conditions
described in Section 1703 or 1704, from making payments at any time of or on
account of the principal of, premium, if any, Additional Amounts, if any or
interest on the Securities or on account of the purchase or other acquisition of
the Securities, or (b) the application by the Trustee of any money deposited
with it hereunder to the payment of or on account of the principal of, premium,
if any, Additional Amounts, if any, or interest on the Securities or the
retention of such payment by the Holders, if, at the time of such application by
the Trustee, it did not have knowledge (in accordance with Section 1706) that
such payment would have been prohibited by the provisions of this Article.

SECTION 1713.  Trustee to Effectuate Subordination.

         Each Holder of a Security by his acceptance thereof authorizes and
directs the Trustee on his behalf to take such action as may be necessary or
appropriate to effectuate the subordination provided in this Article and
appoints the Trustee his attorney-in-fact for any and all such purposes.

SECTION 1714.  Reliance on Judicial Order or Certificate of Liquidating Agent.

         Upon any payment or distribution of assets of the Company referred to
in this Article, the Trustee, subject to the provisions of Section 601, and the
Holders of the Securities shall be entitled to conclusively rely upon any order
or decree entered by any court of competent jurisdiction in which such
insolvency, bankruptcy, receivership, liquidation, reorganization, dissolution,
winding up or similar case or proceeding is pending, or a certificate of the
trustee in bankruptcy, receiver, liquidating trustee, custodian, assignee for


                                      -78-
<PAGE>   85
the benefit of creditors, agent or other Person making such payment or
distribution, delivered to the Trustee or to the Holders of Securities, for the
purpose of ascertaining the Persons entitled to participate in such payment or
distribution, the holders of Senior Debt and other indebtedness of the Company,
the amount thereof or payable thereon, the amount or amounts paid or distributed
thereon and all other facts pertinent thereto or to this Article.

SECTION 1715.  Article Applicable to Paying Agents.

         In case at any time any Paying Agent other than the Trustee shall have
been appointed by the Company and be then acting hereunder, the term "Trustee"
as used in this Article shall in such case (unless the context otherwise
requires) be construed as extending to and including such Paying Agent within
its meaning as fully for all intents and purposes as if such Paying Agent were
named in this Article in addition to or in place of the Trustee.

         This Indenture may be executed in any number of counterparts, each of
which so executed shall be deemed to be an original, but all such counterparts
shall together constitute but one and the same Indenture.

         IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be
duly executed by their respective officers hereunto duly authorized, all as of
the day and year first above written.

                                       REGIONS FINANCIAL CORPORATION

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

                                       BANKERS TRUST COMPANY, as Trustee

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


                                      -79-
<PAGE>   86
                                                                    EXHIBIT A-1


               FORM OF CERTIFICATE TO BE GIVEN BY PERSON ENTITLED
                TO RECEIVE BEARER SECURITY OR TO OBTAIN INTEREST
                       PAYABLE PRIOR TO THE EXCHANGE DATE
                                   CERTIFICATE

[Insert title or sufficient description of Securities to be delivered]

         This is to certify that, as of the date hereof, and except as set forth
below, the above-captioned Securities held by you for our account (i) are owned
by person(s) that are not citizens or residents of the United States, domestic
companies, or any estate or trust the income of which is subject to United
States federal income taxation regardless of its source ("United States
person(s)"), (ii) are owned by United States person(s) that are (a) foreign
branches of United States financial institutions (financial institutions, as
defined in United States Treasury Regulations Section 1.165-12(c)(1)(v) are
herein referred to as "financial institutions") purchasing for their own account
or for resale, or (b) United States person(s) who acquired the Securities
through foreign branches of United States financial institutions and who hold
the Securities through such United States financial institutions on the date
hereof (and in either case (a) or (b), each such United States financial
institution hereby agrees, on its own behalf or through its agent, that you may
advise Regions Financial Corporation or its agent that such financial
institution will comply with the requirements of Section 165(j)(3)(A), (B) or
(C) of the United States Internal Revenue Code of 1986, as amended, and the
regulations thereunder), or (iii) are owned by United States or foreign
financial institution(s) for purposes of resale during the restricted period (as
defined in United States Treasury Regulations Section 1.163-5(c)(2)(i)(D)(7)),
and, in addition, if the owner is a United States or foreign financial
institution described in clause (iii) above (whether or not also described in
clause (i) or (ii)), this is to further certify that such financial institution
has not acquired the Securities for purposes of resale directly or indirectly to
a United States person or to a person within the United States or its
possessions.

         As used herein, "United States" means the United States of America
(including the States and the District of Columbia); and "possessions" include
Puerto Rico, the U.S. Virgin Islands, Guam, American Samoa, Wake Island and the
Northern Mariana Islands.

         We undertake to advise you promptly by tested telex on or prior to the
date on which you intend to submit your certification relating to the above-
captioned Securities held by you for our account in accordance with your
operating procedures if any applicable statement herein is not correct on such
date, and in the absence of any such notification it may be assumed that this
certification applies as of such date.

         This certificate excepts and does not relate to [U.S. $]_________ of
such interest in the above-captioned Securities in respect of which we are not
able to certify and as to which we understand an exchange for an interest in a
permanent global Security or an exchange for and delivery of definitive
Securities (or, if relevant, collection of any interest) cannot be made until we
do so certify.

         We understand that this certificate may be required in connection with
certain tax legislation in the United States. If administrative or legal
proceedings are commenced or threatened in connection with which this
certificate is or would be relevant, we irrevocably authorize you to produce
this certificate or a copy thereof to any interested party in such proceedings.

Dated:  _________________, 200_

         [To be dated no earlier than the 15th day prior to (i) the Exchange
Date or (ii) the relevant Interest Payment Date occurring prior to the Exchange
Date, as applicable]

                      [Name of Person Making Certification]

                       (Authorized Signatory) Name: Title:


<PAGE>   87
                                                                     EXHIBIT A-2

                  FORM OF CERTIFICATE TO BE GIVEN BY EUROCLEAR
                 AND CEDEL S.A. IN CONNECTION WITH THE EXCHANGE
                OF A PORTION OF A TEMPORARY GLOBAL SECURITY OR TO
               OBTAIN INTEREST PAYABLE PRIOR TO THE EXCHANGE DATE
                                   CERTIFICATE

[Insert title or sufficient description of Securities to be delivered]

         This is to certify that, based solely on written certifications that we
have received in writing, by tested telex or by electronic transmission from
each of the persons appearing in our records as persons entitled to a portion of
the principal amount set forth below (our "Member Organizations") substantially
in the form attached hereto, as of the date hereof, [U.S. $] ___________________
principal amount of the above-captioned Securities (i) is owned by person(s)
that are not citizens or residents of the United States, domestic companies,
domestic corporations or any estate or trust the income of which is subject to
United States Federal income taxation regardless of its source ("United States
person(s)"), (ii) is owned by United States person(s) that are (a) foreign
branches of United States financial institutions (financial institutions, as
defined in U.S. Treasury Regulations Section 1.165-12(c)(1)(v) are herein
referred to as "financial institutions") purchasing for their own account or for
resale, or (b) United States person(s) who acquired the Securities through
foreign branches of United States financial institutions and who hold the
Securities through such United States financial institutions on the date hereof
(and in either case (a) or (b), each such financial institution has agreed, on
its own behalf or through its agent, that we may advise Regions Financial
Corporation or its agent that such financial institution will comply with the
requirements of Section 165(j)(3)(A), (B) or (C) of the Internal Revenue Code of
1986, as amended, and the regulations thereunder), or (iii) is owned by United
States or foreign financial institution(s) for purposes of resale during the
restricted period (as defined in United States Treasury Regulations Section
1.163-5(c)(2)(i)(D)(7)), and, to the further effect, that financial institutions
described in clause (iii) above (whether or not also described in clause (i) or
(ii)) have certified that they have not acquired the Securities for purposes of
resale directly or indirectly to a United States person or to a person within
the United States or its possessions.

         As used herein, "United States" means the United States of America
(including the States and the District of Columbia); and its "possessions"
include Puerto Rico, the U.S. Virgin Islands, Guam, American Samoa, Wake Island
and the Northern Mariana Islands.

         We further certify that (i) we are not making available herewith for
exchange (or, if relevant, collection of any interest) any portion of the
temporary global Security representing the above captioned Securities excepted
in the above-referenced certificates of Member Organizations and (ii) as of the
date hereof we have not received any notification from any of our Member
Organizations to the effect that the statements made by such Member
Organizations with respect to any portion of the part submitted herewith for
exchange (or, if relevant, collection of any interest) are no longer true and
cannot be relied upon as of the date hereof.

         We understand that this certification is required in connection with
certain tax legislation in the United States. If administrative or legal
proceedings are commenced or threatened in connection with which this
certificate is or would be relevant, we irrevocably authorize you to produce
this certificate or a copy thereof to any interested party in such proceedings.

Dated: ____________ 200_

[To be dated no earlier than the Exchange Date or the relevant Interest Payment
Date occurring prior to the Exchange Date, as applicable]

                              [Clearstream Banking, societe anonyme,] as
                              Operator of the Euroclear System [Cedel S.A.]

                              By:
                                 ------------------------------------------



<PAGE>   88
                                                                       EXHIBIT B

                                     FORM OF
                       EXCHANGE RATE OFFICER'S CERTIFICATE

         The undersigned, ______________________________, an officer of Regions
Financial Corporation, a Delaware corporation (the "Company"), in accordance
with the terms of the Indenture, dated as of _________________, 2001, between
the Company and Bankers Trust Company, as Trustee (the "Indenture"), and
pursuant to authority delegated by the Board of Directors of the Company to the
undersigned in resolutions duly adopted by such Board at a meeting duly called
and held on __________, _______ (the "Resolutions"), does hereby certify that:

         1. The [exchange rate] [applicable bid quotation] in respect of the
payment to be made on [insert date] by the Company with respect to its [insert
title of security] is ____________________.

         2. The amount payable on [insert date] in respect of the Company's
[insert title of security] is ______________ per [$1,000] principal amount of
such security.

        IN WITNESS WHEREOF, I have hereunto signed by name.

                                           ----------------------------
Dated:                               Name:
       ----------------                    ----------------------------
                                     Title
                                            ---------------------------