<PAGE>

                                                               Exhibit 4(d)(iii)



                            FIRST UNION CORPORATION,



                              WACHOVIA CORPORATION

                                       AND

                            THE CHASE MANHATTAN BANK,

                                                 as Trustee







                          SECOND SUPPLEMENTAL INDENTURE

                           Dated as of August 31, 2001

                                       to

                                    INDENTURE

                          Dated as of November 25, 1992

                             SUBORDINATED SECURITIES

<PAGE>

                  SECOND SUPPLEMENTAL INDENTURE, dated as of August 31, 2001,
among FIRST UNION CORPORATION, a North Carolina corporation ("Successor"),
WACHOVIA CORPORATION, a North Carolina corporation ("Wachovia"), and THE CHASE
MANHATTAN BANK, a New York banking corporation, as successor to Chemical Bank, a
New York banking corporation, as trustee (the "Trustee").

                  WHEREAS, Central Fidelity Banks, Inc., a Virginia corporation
("Central Fidelity"), and the Trustee entered into an Indenture, dated as of
November 25, 1992, (the "Original Indenture") and Wachovia and the Trustee
entered into a First Supplemental Indenture, dated as of December 15, 1997, (the
"First Supplemental Indenture" and, together with the Original Indenture, the
"Indenture"; capitalized terms not otherwise defined herein shall have the
meanings set forth in the Indenture), providing for the issuance from time to
time of Securities;

                  WHEREAS, Wachovia and Successor have entered into an Agreement
and Plan of Merger, dated as of April 15, 2001 (as amended and restated and
otherwise amended or modified, the "Merger Agreement"), which contemplates the
execution and filing of articles of merger (the "Articles of Merger") providing
for the merger of Wachovia with and into Successor (the "Merger"), with
Successor continuing its corporate existence under the laws of the State of
North Carolina;

                  WHEREAS, Section 10.01 of the Indenture provides, among other
things, that the Company shall not merge into another corporation unless, among
other things, the corporation into which the Company is merged expressly shall
assume by a supplemental indenture executed and delivered to the Trustee in form
satisfactory to the Trustee, the due and punctual payment of the principal of
and any premium and interest on the Securities, according to their terms, and
the performance of every covenant of the Indenture and in such series on the
part of the Company to be performed or observed;

                  WHEREAS, Section 9.01 of the Indenture provides, among other
things, that, without the consent of any Holders, the Company, when authorized
by the resolutions of the Board of Directors, and the Trustee from time to time
and at any time may enter into an indenture or indentures supplemental to the
Indenture to evidence the succession of another corporation to the Company and
the assumptions by the successor corporation of the covenants, agreements and
obligations of the Company pursuant to Article Ten of the Indenture;

                  WHEREAS, Successor and Wachovia desire and have requested that
the Trustee join in the execution of this Second Supplemental Indenture for the
purpose of evidencing such succession and assumption;

                  WHEREAS, the execution and delivery of this Second
Supplemental Indenture has been authorized by resolutions of the boards of
directors of Wachovia and Successor; and

                  WHEREAS, all conditions precedent and requirements necessary
to make this Second Supplemental Indenture a valid and legally binding
instrument in accordance with its terms have been complied with, performed and
fulfilled and the execution and delivery hereof have been in all respects duly
authorized;

<PAGE>

                  NOW, THEREFORE, THIS SECOND SUPPLEMENTAL INDENTURE WITNESSETH:

                  For and in consideration of the premises and intending to be
legally bound hereby, it is mutually covenanted and agreed, for the equal and
proportionate benefit of all Holders, as follows:

                                  ARTICLE ONE

                    REPRESENTATIONS OF WACHOVIA AND SUCCESSOR

                  Each of Wachovia and Successor represents and warrants to the
Trustee as follows:

                  SECTION 1.1. It is a corporation duly organized, validly
existing and in good standing under the laws of the State of North Carolina.

                  SECTION 1.2. The execution, delivery and performance by it of
this Second Supplemental Indenture have been authorized and approved by all
necessary corporate action on the part of it.

                  SECTION 1.3. The Merger will become effective in accordance
with the terms of the Merger Agreement and North Carolina law when the Articles
of Merger are filed in the office of the Secretary of State of the State of
North Carolina, or at such later date or time as the Successor and Wachovia
agree and specify in the Articles of Merger (the time the Merger becomes
effective being the "Effective Time").

                  SECTION 1.4. Immediately after giving effect to the Merger, no
Event of Default, and no event which, after notice or lapse of time or both,
would become an Event of Default, shall have happened and be continuing.

                                  ARTICLE TWO

                            ASSUMPTION AND AGREEMENTS

                  SECTION 2.1. Successor hereby assumes the due and punctual
payment of the principal of and any premium and interest on the Securities,
according to their terms, and the performance of every covenant of the Indenture
and in such series on the part of the Company to be performed or observed.

                  SECTION 2.2. Securities authenticated and delivered after the
execution of this Second Supplemental Indenture may bear a notation in form
acceptable to the Trustee as to any matter provided for in this Second
Supplemental Indenture.

                  SECTION 2.3. Successor shall succeed to, and be substituted
for, and may exercise every right and power of, the Company under the Indenture,
with the same effect as if Successor had been named as the Company therein, and
hereafter Wachovia shall be relieved of all obligations and covenants under the
Indenture and the Securities of each series and any related coupons.

<PAGE>


                                  ARTICLE THREE

                                  MISCELLANEOUS

                  SECTION 3.1. The recitals contained in this Second
Supplemental Indenture shall be taken as the statements of the Company and
Successor, and the Trustee assumes no responsibility for the correctness of the
same. The Trustee makes no representation as to the validity or sufficiency of
this Second Supplemental Indenture.

                  SECTION 3.2. If and to the extent that any provision of this
Second Supplemental Indenture limits, qualifies or conflicts with another
provision hereof or of the Indenture, which is required to be included in the
Indenture or in this Second Supplemental Indenture by any provision of the Trust
Indenture Act, such required provision shall control.

                  SECTION 3.3. Nothing in this Second Supplemental Indenture,
express or implied, shall give to any Person, other than the parties to this
Second Supplemental Indenture, any benefit or any legal or equitable right,
remedy or claim under this Second Supplemental Indenture.

                  SECTION 3.4. This Second Supplemental Indenture shall be
governed by and construed in accordance with the laws of the State of New York.

                  SECTION 3.5. This Second Supplemental Indenture may be
executed in any number of counterparts, each of which shall be an original, but
such counterparts shall together constitute but one and the same instrument.

                  SECTION 3.6. This Second Supplemental Indenture shall become
effective as of the Effective Time.

<PAGE>

                  IN WITNESS WHEREOF, the parties hereto have caused this Second
Supplemental Indenture to be duly executed, and their respective corporate seals
to be hereunto affixed and attested all as of the day and year first above
written.

                              WACHOVIA CORPORATION

                              By /s/ Kenneth W. McAllister
                                ---------------------------------------
                                  Name: Kenneth W. McAllister, Esq.
                                  Title:  Senior Executive Vice President
                                                and General Counsel

(Corporate Seal)

Attest:



/s/ William M. Watson, Jr.
----------------------------------
Secretary

                              FIRST UNION CORPORATION

                              By /s/ Ross E. Jeffries, Jr.
                                -------------------------------------
                                  Name:  Ross E. Jeffries, Jr.
                                  Title: Senior Vice President



(Corporate Seal)

Attest:



/s/ Anthony Augliera
----------------------------------
Assistant Secretary

<PAGE>

                                     THE CHASE MANHATTAN BANK, as Trustee



                                     By /s/ J. Adamis
                                       -------------------------------------
                                         Name:  J. Adamis
                                         Title: Vice President



(Corporate Seal)

Attest:



/s/ ILLEGIBLE
----------------------------------




<PAGE>

STATE OF North Carolina    )
                           ):  ss.:
COUNTY OF Forsyth          )



                  On this 31st day of August, 2001, before me, the undersigned
officer, personally appeared Kenneth W. McAllister, who acknowledged himself or
herself to be the Senior Executive Vice President and General Counsel of
WACHOVIA CORPORATION, a North Carolina corporation, and that he or she as such
officer, being authorized to do so, executed the foregoing instrument for the
purposes therein contained by signing the name of the corporation by himself or
herself as such officer.

                  IN WITNESS WHEREOF, I hereunto set my hand and official seal.




                                          /s/ M. Marie Harper
                                          ----------------------------------
                                          Notary Public

[SEAL]



STATE OF North Carolina    )
                           ):  ss.:
COUNTY OF Mecklenburg      )



                  On this 31st day of August, 2001, before me, the undersigned
officer, personally appeared Ross E. Jeffries, Jr., who acknowledged himself or
herself to be the Senior Vice President of FIRST UNION CORPORATION, a North
Carolina corporation, and that he or she as such officer, being authorized to do
so, executed the foregoing instrument for the purposes therein contained by
signing the name of the corporation by himself or herself as such officer.

                  IN WITNESS WHEREOF, I hereunto set my hand and official seal.




                                          /s/ Loretta M. Lucenti
                                          ----------------------------------
                                          Notary Public

[SEAL]






<PAGE>

STATE OF New York          )
                           ):  ss.:
COUNTY OF New York         )


                  On this 31st day of August, 2001, before me, the undersigned
officer, personally appeared Joanne Adamis, who acknowledged himself or
herself to be the Vice President of THE CHASE MANHATTAN BANK, a New York
banking corporation, and that he or she as such officer, being authorized to do
so, executed the foregoing instrument for the purposes therein contained by
signing the name of the association by himself or herself as such officer.

                  IN WITNESS WHEREOF, I hereunto set my hand and official seal.





                                          /s/ Robert J. Stanislaro
                                          ----------------------------------
                                          Notary Public

[SEAL]