Exhibit 10.44A

FIRST SUPPLEMENTAL INDENTURE

THIS FIRST SUPPLEMENTAL INDENTURE dated as of October 1, 2006 is by and between
WILMINGTON TRUST COMPANY (herein, together with its successors in interest, the
“Trustee”) and ALABAMA NATIONAL BANCORPORATION, a Delaware corporation (the
“Company”).

NOW, THEREFORE, in consideration of the premises and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged by
the parties hereto, the Trustee and the Company hereby agree as follows:

PRELIMINARY STATEMENTS

The Trustee and The PB Financial Services Corporation, a Georgia corporation
(“PB Financial”) are parties to that certain Junior Subordinated Indenture dated
as of December 20, 2002 (the “Indenture”).

As permitted by the terms of the Indenture, PB Financial, simultaneously with
the effectiveness of this First Supplemental Indenture, shall merge (referred to
herein for purposes of Article VIII of the Indenture as the “Merger”) with and
into the Company with the Company as the surviving corporation. The parties
hereto are entering into this First Supplemental Indenture pursuant to, and in
accordance with, Articles VIII and IX of the Indenture.

SECTION 1. Definitions. All capitalized terms used herein that are defined in
the Indenture, either directly or by reference therein, shall have the
respective meanings assigned them in the Indenture except as otherwise provided
herein or unless the context otherwise requires.

SECTION 2. Interpretation.

 

  (a) In this First Supplemental Indenture, unless a clear contrary intention
appears:

 

  (i) the singular number includes the plural number and vice versa;

 

  (ii) reference to any gender includes the other gender;

 

  (iii) the words “herein,” “hereof” and “hereunder” and other words of similar
import refer to this First Supplemental Indenture as a whole and not to any
particular Section or other subdivision;

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  (iv) reference to any Person includes such Person’s successors and assigns
but, if applicable, only if such successors and assigns are permitted by this
First Supplemental Indenture or the Indenture, and reference to a Person in a
particular capacity excludes such Person in any other capacity or individually
provided that nothing in this clause (iv) is intended to authorize any
assignment not otherwise permitted by this First Supplemental Indenture or the
Indenture;

 

  (v) reference to any agreement, document or instrument means such agreement,
document or instrument as amended, supplemented or modified and in effect from
time to time in accordance with the terms thereof and, if applicable, the terms
hereof, as well as any substitution or replacement therefor and reference to any
note includes modifications thereof and any note issued in extension or renewal
thereof or in substitution or replacement therefor;

 

  (vi) reference to any Section means such Section of this First Supplemental
Indenture; and

 

  (vii) the word “including” (and with correlative meaning “include”) means
including without limiting the generality of any description preceding such
term.

 

  (b) No provision in this First Supplemental Indenture shall be interpreted or
construed against any Person because that Person or its legal representative
drafted such provision.

SECTION 3. Assumption of Obligations.

 

  (a) Pursuant to, and in compliance and accordance with, Section 8.1(1) of the
Indenture, the Company hereby expressly assumes the due and punctual payment of
the principal of (and premium, if any), interest (including Additional Interest,
if any) and Additional Sums, if any, on all of the Securities of every series,
and the due and punctual performance of every covenant of the Indenture to be
performed or observed by PB Financial under the Indenture.

 

  (b) Pursuant to, and in compliance and accordance with, Section 8.2 of the
Indenture, the Company succeeds to and is substituted for PB Financial, with the
same effect as if the Company had originally been named in the Indenture as the
Company.

SECTION 4. Representations and Warranties. The Company represents and warrants
that (a) it has all necessary power and authority to execute and deliver this
First Supplemental Indenture and to perform the Indenture, (b) that it is the
successor of PB Financial

 

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pursuant to a valid merger effected in accordance with applicable law, (c) that
it is a corporation organized and existing under the laws of Delaware, (d) that
both immediately before and after giving effect to this First Supplemental
Indenture, no Default or Event of Default, and no event which, after notice or
lapse of time or both, would become an Event of Default, shall have occurred and
is continuing and (e) that this First Supplemental Indenture is executed and
delivered pursuant to Section 9.1 and Article VIII of the Indenture and does not
require the consent of the Holders.

SECTION 5. Conditions of Effectiveness. This First Supplemental Indenture shall
become effective simultaneously with the effectiveness of the Merger, provided,
however, that:

 

  (a) the Trustee shall have executed a counterpart of this First Supplemental
Indenture and shall have received one or more counterparts of this First
Supplemental Indenture executed by the Company;

 

  (b) the Trustee shall have received an Officer’s Certificate stating that
(i) the conditions contained in Articles VIII and IX of the Indenture have been
complied with, (ii) the Merger and the First Supplemental Indenture comply with
Article VIII of the Indenture and all conditions precedent therein provided for
relating to the Merger have been complied with and met, and (iii) the execution
of the Supplemental Indenture is authorized by the Indenture.

 

  (c) the Trustee shall have received an Opinion of Counsel to the effect that
(i) all conditions precedent provided for in the Indenture relating to the
Merger and the execution of the First Supplemental Indenture have been complied
with; (ii) the execution of this First Supplemental Indenture complies with the
requirements of Article IX of the Indenture and is authorized or permitted by,
and conforms to, the terms of Article IX of the Indenture; (iii) it is proper
for the Trustee, under the provisions of Article IX of the Indenture, to join in
the execution of the First Supplemental Indenture; and (iv) the Merger and the
subsequent assumption and this First Supplemental Indenture are permitted under
Article VIII of the Indenture and comply with the provisions of Article VIII of
the Indenture; and

 

  (d) the Company and PB Financial shall have duly executed and filed with the
Secretaries of the State of the States of Delaware and Georgia a Certificate or
Articles of Merger.

SECTION 6. Reference to the Indenture.

 

  (a) Upon the effectiveness of this First Supplemental Indenture, each
reference in the Indenture to “this Indenture,” “hereunder,” “herein” or words
of like import shall mean and be a reference to the Indenture, as affected,
amended and supplemented hereby.

 

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  (b) Upon the effectiveness of this First Supplemental Indenture, each
reference in the Securities to the Indenture including each term defined by
reference to the Indenture shall mean and be a reference to the Indenture or
such term, as the case may be, as affected, amended and supplemented hereby.

 

  (c) The Indenture, as amended and supplemented hereby shall remain in full
force and effect and is hereby ratified and confirmed.

SECTION 7. Execution in Counterparts. This First Supplemental Indenture may be
executed in any number of counterparts and by different parties hereto in
separate counterparts, each of which when so executed and delivered shall be
deemed to be an original and all of which when taken together shall constitute
but one and the same instrument.

SECTION 8. Governing Law; Binding Effect. This First Supplemental Indenture
shall be governed by and construed in accordance with the laws of the State of
New York and shall be binding upon the parties hereto and their respective
successors and assigns.

SECTION 9. The Trustee. The Trustee shall not be responsible in any manner
whatsoever for or in respect of the validity or sufficiency of this First
Supplemental Indenture or the due execution thereof by the Company or the
Successor Company. The recitals of fact contained herein shall be taken as the
statements solely of the Company and the Trustee assumes no responsibility for
the correctness thereof.

[Signatures on following page]

 

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

 

ALABAMA NATIONAL BANCORPORATION By:   /s/ William E. Matthews, V Name:   William
E. Matthews, V Title:   EVP and CFO

WILMINGTON TRUST COMPANY, not in its individual

capacity, but solely as Trustee

By:   /s/ Michael G. Oller, Jr. Name:   Michael G. Oller, Jr. Title:   Senior
Financial Services Officer

 

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