<PAGE>   1
                                                                   EXHIBIT 10.5

                                PROMISSORY NOTE


<TABLE>
<CAPTION>
----------------- ------------- ------------- -------------- --------- ----------- ------------ ------------ --------------
     PRINCIPAL       LOAN DATE     MATURITY       LOAN NO.      CALL    COLLATERAL    ACCOUNT      OFFICER       INITIALS
<S>               <C>           <C>           <C>            <C>       <C>         <C>          <C>          <C>
    $860,000        03-31-2000    06-30-2000                                                         JLN
----------------- ------------- ------------- -------------- --------- ----------- ------------ ------------ --------------
References in the shaded area are for Lender's use only and do not limit the applicability of this document to any
particular loan or item.
---------------------------------------------------------------------------------------------------------------------------
</TABLE>

BORROWER: SOUTHERNBANK, N.A.                 LENDER:  THE BANKERS BANK
          P.O. BOX 967                                2410 PACES FERRY ROAD
          BUFORD, GA  30515-0967                      600 PACES SUMMIT
                                                      ATLANTA, GA  30339

===============================================================================

<TABLE>
<S>                                <C>                           <C>
PRINCIPAL AMOUNT: $860,000.00      INITIAL RATE: 7.750%          DATE OF NOTE:   MARCH 31, 2000
</TABLE>

PROMISE TO PAY. SOUTHERNBANK, N.A. (IO) ("BORROWER") PROMISES TO PAY TO THE
BANKERS BANK ("LENDER"), OR ORDER, IN LAWFUL MONEY OF THE UNITED STATES OF
AMERICA, THE PRINCIPAL AMOUNT OF EIGHT HUNDRED SIXTY THOUSAND & 00/100 DOLLARS
($860,000.00), TOGETHER WITH INTEREST ON THE UNPAID OUTSTANDING PRINCIPAL
BALANCE FROM MARCH 31, 2000, UNTIL PAID IN FULL.

PAYMENT. BORROWER WILL PAY THIS LOAN IN ONE PAYMENT OF $860,000 PLUS INTEREST ON
JUNE 30, 2000. THIS PAYMENT DUE ON JUNE 30, 2000, WILL BE FOR ALL PRINCIPAL AND
ACCRUED INTEREST NOT YET PAID. Borrower will pay Lender at Lender's
address shown above or at such other place as Lender may designate in writing.
Unless otherwise agreed or required by applicable law, payments will be applied
first to accrued unpaid interest, then to principal, and any remaining amount
to any unpaid collection costs and late charges.

VARIABLE INTEREST RATE. The interest rate on this Note is subject to change
from time to time based on changes in an index which is the Prime rate as
published in the Money Rates section of the Wall Street Journal. (the "Index").
If two or more rates exist, then the highest rate will prevail. Lender will
tell Borrower the current Index rate upon Borrower's request. Borrower
understands that Lender may make loans based on other rates as well. The
interest rate change will not occur more often than each day. THE INDEX
CURRENTLY IS 8.750% PER ANNUM. THE INTEREST RATE TO BE APPLIED TO THE UNPAID
PRINCIPAL BALANCE OF THIS NOTE WILL BE AT A RATE OF 1.000 PERCENTAGE POINT
UNDER THE INDEX, RESULTING IN AN INITIAL ANNUAL RATE OF SIMPLE INTEREST OF
7.750%. NOTICE: Under no circumstances will the interest rate on this Note be
more than the maximum rate allowed by applicable law.

PREPAYMENT. Borrower may pay without penalty all or a portion of the amount
owed earlier than it is due. Early payments will not, unless agreed to by
Lender in writing, relieve Borrower of Borrower's obligation to continue to
make payments under the payment schedule. Rather, they will reduce the
principal balance due.

LATE CHARGE. If a payment is 15 DAYS OR MORE LATE, Borrower will be charged
$100.00.



<PAGE>   2

03-06-2000                      PROMISSORY NOTE                         PAGE 2
Loan No. 4021395101               (Continued)



DEFAULT. Borrower will be in default if any of the following happens: (a)
Borrower fails to make any payment when due. (b) Borrower breaks any promise
Borrower has made to Lender, or Borrower fails to comply with or to perform when
due any other term, obligation, covenant, or condition contained in this Note or
any agreement related to this Note, or in any other agreement or loan Borrower
has with Lender. (c) Any representation or statement made or furnished to Lender
by Borrower or on Borrower's behalf is false or misleading in any material
respect either now or at the time made or furnished. (d) Borrower becomes
insolvent, a receiver is appointed for any part of Borrower's property, Borrower
makes an assignment for the benefit of creditors, or any proceeding is commenced
either by Borrower or against Borrower under any bankruptcy or insolvency laws.
(e) Any creditor tries to take any of Borrower's property on or in which Lender
has a lien or security interest. This includes a garnishment of any of
Borrower's accounts with Lender. (f) Any guarantor dies or any of the other
events described in this default section occurs with respect to any guarantor of
this Note. (g) A material adverse change occurs in Borrower's financial
condition, or Lender believes the prospect of payment or performance of the
Indebtedness is impaired. (h) Lender in good faith deems itself insecure.

LENDER'S RIGHTS. Upon default, Lender may declare the entire unpaid principal
balance on this Note and all accrued unpaid interest immediately due, without
notice, and then Borrower will pay that amount. Upon default, including failure
to pay upon final maturity, Lender, at its option, may also, if permitted under
applicable law, increase the variable interest rate on this Note 3.000
percentage points. The interest rate will not exceed the maximum rate permitted
by applicable law. Lender may hire or pay someone else to help collect this
Note if Borrower does not pay. Borrower also will pay Lender that amount. This
includes, subject to any limits under applicable law, Lender's, costs of
collection, including court costs and fifteen percent (15%) of the principal
plus accrued interest as attorneys' fees, it any sums owing under this Note are
collected by or through an attorney-at-law, whether or not there is a lawsuit,
and legal expenses for bankruptcy proceedings (including efforts to modify or
vacate any automatic stay or injunction), appeals, and any anticipated
post-judgment collection services. If not prohibited by applicable law,
Borrower also will pay any court costs, in addition to all other sums provided
by law. THIS NOTE HAS BEEN DELIVERED TO LENDER AND ACCEPTED BY LENDER IN THE
STATE OF GEORGIA. SUBJECT TO THE PROVISIONS ON ARBITRATION, THIS NOTE SHALL BE
GOVERNED BY AND CONSTRUED in ACCORDANCE WITH THE LAWS OF THE STATE OF GEORGIA.

DISHONORED ITEM FEE. Borrower will pay a fee to Lender of twenty dollars
($20.00) or five percent (5%) of the face amount of the check, whichever is
greater, if Borrower makes a payment an Borrower's loan and the check or
preauthorized charge with which Borrower pays is later dishonored.

RIGHT OF SETOFF. Borrower grants to Lender a contractual possessory security
interest in, and hereby assigns, conveys, delivers, pledges, and transfers to
Lender all Borrower's right, title and interest in and to, Borrower's accounts
with Lender (whether checking, savings, or some other account), including
without limitation all accounts held jointly with someone else and all accounts


<PAGE>   3

03-06-2000                       PROMISSORY NOTE                         PAGE 3
Loan No. 4021395101                (Continued)



Borrower may open in the future, excluding however all IRA and Keogh accounts,
and all trust accounts for which the grant of a security interest would be
prohibited by law. Borrower authorizes Lender, to the extent permitted by
applicable law, to charge or setoff all sums owing on this Note against any and
all such accounts.

ARBITRATION. LENDER AND BORROWER AGREE THAT ALL DISPUTES, CLAIMS AND
CONTROVERSIES BETWEEN THEM, WHETHER INDIVIDUAL, JOINT, OR CLASS IN NATURE,
ARISING FROM THIS NOTE OR OTHERWISE, INCLUDING WITHOUT LIMITATION CONTRACT AND
TORT DISPUTES, SHALL BE ARBITRATED PURSUANT TO THE RULES OF THE AMERICAN
ARBITRATION ASSOCIATION, UPON REQUEST OF EITHER PARTY. No act to take or
dispose of any collateral securing this Note shall constitute a waiver of this
arbitration agreement or be prohibited by this arbitration agreement. This
includes, without limitation, obtaining injunctive relief or a temporary
restraining order; invoking a power of sale under any deed of trust or
mortgage; obtaining a writ of attachment or imposition of a receiver; or
exercising any rights relating to personal property, including taking or
disposing of such property with or without judicial process pursuant to Article
9 of the Uniform Commercial Code. Any disputes, claims, or controversies
concerning the lawfulness or reasonableness of any act, or exercise of any
right, concerning any collateral securing this Note, including any claim to
rescind, reform, or otherwise modify any agreement relating to the collateral
securing this Note, shall also be arbitrated, provided however that no
arbitrator shall have the right or the power to enjoin or restrain any act of
any party. Judgment upon any award rendered by any arbitrator may be entered in
any court having jurisdiction. Nothing in this Note shall preclude any party
from seeking equitable relief from a court of competent jurisdiction. The
statute of limitations, estoppel, waiver, laches, and similar doctrines which
would otherwise be applicable in an action brought by a party shall be
applicable in any arbitration proceeding, and the commencement of an
arbitration proceeding shall be deemed the commencement of an action for these
purposes. The

<PAGE>   4

03-06-2000                       PROMISSORY NOTE                         PAGE 4
Loan No. 4021395101                (Continued)



Federal Arbitration Act shall apply to the construction, interpretation, and
enforcement of this arbitration provision.

ACCRUAL METHOD.  INTEREST WILL BE CALCULATED ON AN ACTUAL/360 DAY BASIS.

     GENERAL PROVISIONS. Lender may delay or forgo enforcing any of its rights
     or remedies under this Note without losing them. Borrower and any other
     person who signs, guarantees or endorses this Note, to the extent allowed
     by law, Waive Presentment, demand for payment, protest and notice of
     dishonor. Upon any change in the terms of this Note, and unless otherwise
     expressly stated in writing, no party who signs this Note, whether as
     maker, guarantor, accommodation maker or endorser, shall be released from
     liability. All such parties waive any right to require Lender to take
     action against any other party who signs this Note as provided in O.C.G.A.
     Section 10-7-24 and agree that Lender may renew or extend (repeatedly and
     for any length of time) this loan, or release any party or guarantor or
     collateral; or impair, fail to realize upon or perfect Lender's security
     interest in the collateral; and lake any other action deemed necessary by
     Lender without the consent of or notice to anyone. All such parties also
     agree that Lender may modify this loan without the consent of or notice to
     anyone other than the party with whom the modification is made.

     IN WITNESS WHEREOF, THIS NOTE HAS BEEN SIGNED AND SEALED BY THE
     UNDERSIGNED, WHO ACKNOWLEDGES A COMPLETED COPY HEREOF.

     BORROWER:

     SOUTHERNBANK, N.A. (IO), INC.

<TABLE>
     <S>                                          <C>
     BY:                             (SEAL)       BY:                                (SEAL)
         ----------------------------                  -------------------------------
         D. ARNOLD TILLMAN, CEO                        M. LAUCH MCKINNON, PRESIDENT
</TABLE>



LENDER:

THE BANKERS BANK

BY:
   ---------------------------------------
   AUTHORIZED OFFICER
<PAGE>   5

                          FORM OF COMMERCIAL GUARANTY

<TABLE>
<CAPTION>
-------------- ------------ ------------ ------------ ----------- ------------ ------------ ------------ ------------
  PRINCIPAL     LOAN DATE    MATURITY     LOAN NO.       CALL     COLLATERAL     ACCOUNT      OFFICER     INITIALS
<S>            <C>          <C>          <C>          <C>         <C>          <C>          <C>          <C>
                                                                                                JLN
-------------- ------------ ------------ ------------ ----------- ------------ ------------ ------------ ------------
 References in the shaded area are for Lender's use only and do not limit the applicability of this document to any
 particular loan or lien.
---------------------------------------------------------------------------------------------------------------------
</TABLE>


BORROWER:    SOUTHERNBANK, N.A. (IO)            LENDER:  THE BANKERS BANK
             P.O. BOX 967                                2410 PACES FERRY ROAD
             BUFORD, GA  30515-0967                      600 PACES FERRY SUMMIT
                                                         ATLANTA, GA  30339
GUARANTOR:


AMOUNT OF GUARANTY. The principal amount of this Guaranty is Eight Hundred Sixty
Thousand & 00/100 Dollars ($860,000.00).

CONTINUING GUARANTY. IN CONSIDERATION OF THE SUM OF FIVE DOLLARS ($5.00) AND
OTHER GOOD AND VALUABLE CONSIDERATION, THE RECEIPT AND ADEQUACY OF WHICH ARE
HEREBY ACKNOWLEDGED BY GUARANTOR AND TO INDUCE LENDER TO MAKE LOANS OR OTHERWISE
EXTEND CREDIT TO BORROWER, OR TO RENEW OR EXTEND IN WHOLE OR IN PART ANY
EXISTING INDEBTEDNESS OF BORROWER TO LENDER, OR TO MAKE OTHER FINANCIAL
ACCOMMODATIONS TO BORROWER,               ("GUARANTOR") ABSOLUTELY AND
UNCONDITIONALLY GUARANTEES AND PROMISES TO PAY TO THE BANKERS BANK ("LENDER") OR
ITS ORDER, IN LEGAL TENDER OF THE UNITED STATES OF AMERICA, THE INDEBTEDNESS (AS
THAT TERM IS DEFINED BELOW) OF SOUTHERNBANK, N.A. (IO) ("BORROWER") TO LENDER ON
THE TERMS AND CONDITIONS SET FORTH IN THIS GUARANTY. THE OBLIGATIONS OF
GUARANTOR UNDER THIS GUARANTY ARE CONTINUING.

DEFINITIONS. The following words shall have the following meanings when used in
this Guaranty:

          BORROWER. The word "Borrower" means SouthernBank N.A. (IO).

          GUARANTOR. The word "Guarantor" means            .

          GUARANTY. The word "Guaranty" means this Guaranty made by Guarantor
          for the benefit of Lender dated March 31, 2000.

          INDEBTEDNESS. The word "Indebtedness" is used in its most
          comprehensive sense and means and includes any and all of Borrower's
          liabilities, obligations, debts, and indebtedness to Lender, now
          existing or hereinafter incurred or created including, without
          limitation, all loans, advances, interest, costs, debts, overdraft
          indebtedness, lease obligations, other obligations, and liabilities of
          Borrower, or any of them, and any present of future judgments against
          Borrower, or any of them; and whether any such Indebtedness is
          voluntarily or involuntarily incurred, due or not due, absolute or
          contingent, liquidated or unliquidated, determined or undetermined;
          whether Borrower may be liable individually or jointly with others or
          primarily or secondarily, or as guarantor or surety; whether recovery
          on the indebtedness may be or may become barred on unenforceable
          against the Borrower for any reason whatsoever; and whether the
          Indebtedness arises from transactions which may be voidable on account
          of infancy, insanity, ultra vires, or otherwise.

          LENDER. The word "Lender" means The Bankers Bank, its successors and
          assigns.


<PAGE>   6


          RELATED DOCUMENTS. The words "Related Documents" mean and include
          without limitation all promissory notes, credit agreements, loan
          agreements, environmental agreements, guaranties, security agreements,
          security deeds, mortgages, deeds of trust, and all other instruments,
          agreements and documents, whether now or hereafter existing, executed
          in connection with the Indebtedness.

MAXIMUM LIABILITY. THE MAXIMUM LIABILITY OF GUARANTOR UNDER THIS GUARANTY SHALL
NOT EXCEED AT ANY ONE TIME THE SUM OF THE PRINCIPAL AMOUNT OF $860,000, PLUS
ALL INTEREST THEREON, PLUS ALL OF LENDER'S COSTS, EXPENSES, AND ATTORNEYS' FEES
INCURRED IN CONNECTION WITH OR RELATING TO (A) THE COLLECTION OF THE
INDEBTEDNESS, (B) THE COLLECTION AND SALE OF ANY COLLATERAL FOR THE
INDEBTEDNESS OR THIS GUARANTY, OR (C) THE ENFORCEMENT OF THIS GUARANTY.
ATTORNEYS' FEES INCLUDE, WITHOUT LIMITATION, ATTORNEYS' FEES WHETHER OR NOT
THERE IS A LAWSUIT, AND IF THERE IS A LAWSUIT, ANY FEES AND COSTS FOR TRIAL AND
APPEALS.

The above limitation on liability is not a restriction on the amount of the
Indebtedness of Borrower to Lender either in the aggregate or at any one time.
If Lender presently holds one or more guaranties, or hereafter receives
additional guaranties from Guarantor, the rights of Lender under all guaranties
shall be cumulative. This Guaranty shall not (unless specifically provided
below to the contrary) affect or invalidate any such other guaranties. The
liability of Guarantor will be the aggregate liability of Guarantor under the
terms of this Guaranty and any such other unterminated guaranties.

NATURE OF GUARANTY. Guarantor's liability under this Guaranty shall be open and
continuous for so long as this Guaranty remains in force. Guarantor intends to
guarantee at all times the performance and prompt payment when due, whether at
maturity or earlier by reason of acceleration or otherwise, of all Indebtedness
within the limits set forth in the preceding section of this Guaranty.
Accordingly, no payments made upon the Indebtedness will discharge or diminish
the continuing liability of Guarantor in connection with any remaining portions
of the Indebtedness or any of the Indebtedness which subsequently arises or is
thereafter incurred or contracted.

DURATION OF GUARANTY. This Guaranty will take effect when received by Lender
without the necessity of any acceptance by Lender, or any notice to Guarantor or
to Borrower, and will continue in full force until all Indebtedness incurred or
contracted before receipt by Lender of any notice of revocation shall have been
fully and finally paid and satisfied and all other obligations of Guarantor
under this Guaranty shall have been performed in full. If Guarantor elects to
revoke this Guaranty, Guarantor may only do so in writing. Guarantor's written
notice of revocation must be mailed to Lender, by certified mail, at the address
of Lender listed above or such other place as Lender may designate in writing.
Written revocation of this Guaranty will apply only to advances or new
Indebtedness created after actual receipt by Lender of Guarantor's written
revocation. For this purpose and without limitation, the term "new Indebtedness"
does not include Indebtedness which at the time of notice of revocation is
contingent, unliquidated, undetermined or not due and which later becomes
absolute, liquidated, determined or due. This Guaranty will continue to bind
Guarantor for all Indebtedness incurred by Borrower or committed by Lender prior
to receipt of Guarantor's written notice of revocation, including any
extensions, renewals, substitutions or modifications of the Indebtedness. All
renewals, extensions, substitutions, and modifications of the Indebtedness
granted after Guarantor's revocation, are contemplated under this Guaranty and,
specifically will not be considered to be new Indebtedness. This Guaranty shall
bind the estate of Guarantor as to Indebtedness created both before and after
the death or incapacity of Guarantor, regardless of Lender's actual notice of
Guarantor's death. Subject to the foregoing, Guarantor's executor or
administrator or other legal representative may terminate this Guaranty in the
same manner in which Guarantor might have terminated it and with the same
effect. Release of any other guarantor or termination of any other guaranty of
the Indebtedness shall not affect the liability of Guarantor under this
Guaranty. A revocation received by Lender from any one or more Guarantors shall
not affect the liability of any remaining Guarantors under this Guaranty. It is
anticipated that fluctuations may occur in the aggregate amount of Indebtedness
covered by this Guaranty, and it is specifically acknowledged and agreed by
Guarantor that reductions in the amount of Indebtedness, even to zero dollars
($0.00), prior to written revocation of this Guaranty by Guarantor shall not
constitute a termination of this Guaranty. This Guaranty is binding upon
Guarantor and Guarantor's heirs, successors and assigns so long as any of the
guaranteed Indebtedness remains unpaid and even though the Indebtedness
guaranteed may from time to time be zero dollars ($0.00).


<PAGE>   7
GUARANTOR'S AUTHORIZATION TO LENDER. Guarantor authorizes Lender, either before
or after any revocation hereof, WITHOUT NOTICE OR DEMAND AND WITHOUT LESSENING
GUARANTOR'S LIABILITY UNDER THIS GUARANTY, FROM TIME TO TIME: (A) PRIOR TO
REVOCATION AS SET FORTH ABOVE, TO MAKE ONE OR MORE ADDITIONAL SECURED OR
UNSECURED LOANS TO BORROWER, TO LEASE EQUIPMENT OR OTHER GOODS TO BORROWER, OR
OTHERWISE TO EXTEND ADDITIONAL CREDIT TO BORROWER; (B) TO ALTER, COMPROMISE,
RENEW, EXTEND, ACCELERATE, OR OTHERWISE CHANGE ONE OR MORE TIMES THE TIME FOR
PAYMENT OR OTHER TERMS OF THE INDEBTEDNESS OR ANY PART OF THE INDEBTEDNESS,
INCLUDING INCREASES AND DECREASES OF THE RATE OF INTEREST ON THE INDEBTEDNESS;
EXTENSIONS MAY BE REPEATED AND MAY BE FOR LONGER THAN THE ORIGINAL LOAN TERM;
(C) TO TAKE AND HOLD SECURITY FOR THE PAYMENT OF THIS GUARANTY OR THE
INDEBTEDNESS, AND EXCHANGE, ENFORCE, WAIVE, SUBORDINATE, FAIL OR DECIDE NOT TO
PERFECT, AND RELEASE ANY SUCH SECURITY, WITH OR WITHOUT THE SUBSTITUTION OF NEW
COLLATERAL; (D) TO RELEASE, SUBSTITUTE, AGREE NOT TO SUE, OR DEAL WITH ANY ONE
OR MORE OF BORROWER'S SURETIES, ENDORSERS, OR OTHER GUARANTORS ON ANY TERMS OR
IN ANY MANNER LENDER MAY CHOOSE; (E) TO DETERMINE HOW, WHEN AND WHAT APPLICATION
OF PAYMENTS AND CREDITS SHALL BE MADE ON THE INDEBTEDNESS; (F) TO APPLY SUCH
SECURITY AND DIRECT THE ORDER OR MANNER OF SALE THEREOF, INCLUDING WITHOUT
LIMITATION, ANY NONJUDICIAL SALE PERMITTED BY THE TERMS OF THE CONTROLLING
SECURITY AGREEMENT OR DEED OF TRUST, AS LENDER IN ITS DISCRETION MAY DETERMINE;
(G) TO SELL, TRANSFER, ASSIGN, OR GRANT PARTICIPATIONS IN ALL OR ANY PART OF THE
INDEBTEDNESS; AND (H) TO ASSIGN OR TRANSFER THIS GUARANTY IN WHOLE OR IN PART,

GUARANTOR'S REPRESENTATIONS AND WARRANTIES. Guarantor represents and warrants
to Lender that (a) no representations or agreements of any kind have been made
to Guarantor which would limit or qualify in any way the terms of this
Guaranty; (b) this Guaranty is executed at Borrower's request and not at the
request of Lender; (c) Guarantor has full power, right and authority to enter
into this Guaranty; (d) the provisions of this Guaranty do not conflict with or
result in a default under any agreement or other instrument binding upon
Guarantor and do not result in a violation of any law, regulation, court decree
or order applicable to Guarantor; (e) Guarantor has not and will not, without
the prior written consent of Lender, sell, lease, assign, encumber,
hypothecate, transfer, or otherwise dispose of all or substantially all of
Guarantor's assets, or any interest therein; (f) upon Lender's request,
Guarantor will provide to Lender financial and credit information in form
acceptable to Lender, and all such financial information which currently has
been, and all future financial information which will be provided to Lender is
and will be true and correct in all material respects and fairly present the
financial condition of Guarantor as of the dates the financial information is
provided; (g) no material adverse change has occurred in Guarantor's financial
condition since the date of the most recent financial statements provided to
Lender and no event has occurred which may materially adversely affect
Guarantor's financial condition; (h) no litigation, claim, investigation,
administrative proceeding or similar action (including those for unpaid taxes)
against Guarantor is pending or threatened; (i) Lender has made no
representation to Guarantor as to the creditworthiness of Borrower; and (j)
Guarantor has established adequate means of obtaining from Borrower on a
continuing basis


<PAGE>   8

information regarding Borrower's financial condition. Guarantor agrees to keep
adequately informed from such means of any facts, events, or circumstances
which might in any way affect Guarantor's risks under this Guaranty, and
Guarantor further agrees that, absent a request for information, Lender shall
have no obligation to disclose to Guarantor any information or documents
acquired by Lender in the course of its relationship with Borrower.

GUARANTOR'S WAIVERS. Except as prohibited by applicable law, Guarantor waives
any right to require Lender (a) to continue lending money or to extend other
credit to Borrower; (b) to make any presentment, protest, demand, or notice of
any kind, including notice of any nonpayment of the Indebtedness or of any
nonpayment related to any collateral, or notice of any action or nonaction on
the part of Borrower, Lender, any surety, endorser, or other guarantor in
connection with the Indebtedness or in connection with the creation of new or
additional loans or obligations; (c) to resort for payment or to proceed
directly or at once against any person, including Borrower or any other
guarantor; (d) to proceed directly against or exhaust any collateral held by
Lender from Borrower, any other guarantor, or any other person; (e) to give
notice of the terms, time, and place of any public or private sale of personal
property security held by Lender from Borrower or to comply with any other
applicable provisions of the Uniform Commercial Code; (f) to pursue any other
remedy within Lender's power; or (g) to commit any act or omission of any kind,
or at any time, with respect to any matter whatsoever.

If now or hereafter (a) Borrower shall be or become insolvent, and (b) the
Indebtedness shall not at all times until paid be fully secured by collateral
pledged by Borrower, Guarantor hereby forever waives and relinquishes in favor
of Lender and Borrower, and their respective successors, any claim or right to
payment Guarantor may now have or hereafter have or acquire against Borrower,
by subrogation or otherwise, so that at no time shall Guarantor be or become a
"creditor" of Borrower within the meaning of 11 U.S.C. section 547(b), or any
successor provision of the Federal bankruptcy laws.

Guarantor also waives any and all rights or defenses arising by reason of (a)
the provisions of O.C.G.A. Section 10-7-24 concerning Guarantor's right to
require Lender to take action against Borrower or any "one action" or
"anti-deficiency" law or any other law which may prevent Lender from bringing
any action, including a claim for deficiency, against Guarantor, before or
after Lender's commencement or completion of any foreclosure action, either
judicially or by exercise of a power of sale; (b) any election of remedies by
Lender which destroys or otherwise adversely affects Guarantor's subrogation
rights or Guarantor's rights to proceed against Borrower for reimbursement,
including without limitation, any loss of rights Guarantor may suffer by reason
of any law limiting, qualifying, or discharging the Indebtedness; (c) any
disability or other defense of Borrower, of any other guarantor, or of any
other person, or by reason of the cessation of Borrower's liability from any
cause whatsoever, other than payment in full in legal tender, of the
Indebtedness; (d) any right to claim discharge of the Indebtedness on the basis
of unjustified impairment of any collateral for the Indebtedness; (e) any
statute of limitations, if at any time any action or suit brought by Lender
against Guarantor is commenced there is outstanding Indebtedness of Borrower to
Lender which is not barred by any applicable statute of limitations; or (f) any
defenses given to guarantors at law or in equity other than actual payment and
performance of the Indebtedness. If payment is made by Borrower, whether
voluntarily or other, or by any third party, on the Indebtedness and thereafter
Lender is forced to


<PAGE>   9

remit the amount of that payment to Borrower's trustee in bankruptcy or to any
similar person under any federal or State bankruptcy law or law for the relief
of debtors, the Indebtedness shall be considered unpaid for the purpose of
enforcement of this Guaranty.

Guarantor further waives and agrees not to assert or claim at any time any
deductions to the amount guaranteed under this Guaranty for any claim of
setoff, counterclaim, counter demand, recoupment or similar right, whether such
claim, demand or right may be asserted by the Borrower, the Guarantor, or both.

GUARANTOR'S UNDERSTANDING WITH RESPECT TO WAIVERS. Guarantor warrants and
agrees that each of the waivers set forth above is made with Guarantor's full
knowledge of its significance and consequences and that, under the
circumstances, the waivers are reasonable and not contrary to public policy or
law. If any such waiver is determined to be contrary to any applicable law or
public policy, such waiver shall be effective only to the extent permitted by
law or public policy.

LENDER'S RIGHT OF SETOFF. In addition to all liens upon and rights of setoff
against the moneys, securities or other property of Guarantor given to Lender
by law, Lender shall have, with respect to Guarantor's obligations to Lender
under this Guaranty and to the extent permitted by law, a contractual
possessory security interest in and a right of setoff against, and Guarantor
hereby assigns, conveys, delivers, pledges, and transfers to Lender all of
Guarantor's right, title and interest in and to, all deposits, moneys,
securities and other property of Guarantor now or hereafter in the possession
of or on deposit with Lender, whether held in a general or special account or
deposit, whether held jointly with someone else, or whether held for
safekeeping or otherwise, excluding however all IRA, Keogh, and trust accounts.
Every such security interest and right of setoff may be exercised without
demand upon or notice to Guarantor. No security interest or right of setoff
shall be deemed to have been waived by any act or conduct on the part of Lender
or by any neglect to exercise such right of setoff or to enforce such security
interest or by any delay in so doing. Every right of setoff and security
interest shall continue in full force and effect until such right of setoff or
security interest is specifically waived or released by an instrument in
writing executed by Lender.

SUBORDINATION OF BORROWER'S DEBTS TO GUARANTOR. Guarantor agrees that the
Indebtedness of Borrower to Lender, whether now existing or hereafter created,
shall be prior to any claim that Guarantor may now have or hereafter acquire
against Borrower, whether or not Borrower becomes insolvent. Guarantor hereby
expressly subordinates any claim Guarantor may have against Borrower, upon any
account whatsoever, to any claim that Lender may now or hereafter have against
Borrower. In the event of insolvency and consequent liquidation of the assets
of Borrower, through bankruptcy, by an assignment for the benefit of creditors,
by voluntary liquidation ' or otherwise, the assets of Borrower applicable to
the payment of the claims of both Lender and Guarantor shall be paid to Lender
and shall be first applied by Lender to the Indebtedness of Borrower to Lender.
Guarantor does hereby assign to Lender all claims which it may have or acquire
against Borrower or against any assignee or trustee in bankruptcy of Borrower;
provided however, that such assignment shall be effective only for the purpose
of assuring to Lender full payment in legal tender of the indebtedness. If
Lender so requests, any notes or credit agreements now or hereafter evidencing
any debts or obligations of Borrower to


<PAGE>   10

Guarantor shall be marked with a legend that the same are subject to this
Guaranty and shall be delivered to Lender. Guarantor agrees, and Lender hereby
is authorized, in the name of Guarantor, from time to time to execute and file
financing statements and continuation statements and to execute such other
documents and to take such other actions as Lender deems necessary or
appropriate to perfect, preserve and enforce its rights under this Guaranty.

MISCELLANEOUS PROVISIONS. The following miscellaneous provisions are a part of
this Guaranty:

         AMENDMENTS. This Guaranty, together with any Related Documents,
         constitutes the entire understanding and agreement of the parties as
         to the matters set forth in this Guaranty. No alteration of or
         amendment to this Guaranty shall be effective unless given in writing
         and signed by the party or parties sought to be charged or bound by
         the alteration or amendment.

         APPLICABLE LAW. This Guaranty has been delivered to Lender and
         accepted by Lender in the State of Georgia. Subject to the provisions
         on arbitration, this Guaranty shall be governed by and construed in
         accordance with the laws of the State of Georgia.

         ARBITRATION. LENDER AND GUARANTOR AGREE THAT ALL DISPUTES, CLAIMS AND
         CONTROVERSIES BETWEEN THEM, WHETHER INDIVIDUAL, JOINT, OR CLASS IN
         NATURE, ARISING FROM THIS GUARANTY OR OTHERWISE, INCLUDING WITHOUT
         LIMITATION CONTRACT AND TORT DISPUTES, SHALL BE ARBITRATED PURSUANT TO
         THE RULES OF THE AMERICAN ARBITRATION ASSOCIATION, UPON REQUEST OF
         EITHER PARTY. No act to take or dispose of any Collateral shall
         constitute a waiver of this arbitration agreement or be prohibited by
         this arbitration agreement. This includes, without limitation,
         obtaining injunctive relief or a temporary restraining order; invoking
         a power of sale under any deed of trust or mortgage; obtaining a writ
         of attachment or imposition of a receiver; or exercising any rights
         relating to personal property, including taking or disposing of such
         property with or without judicial process pursuant to Article 9 of the
         Uniform Commercial Code. Any disputes, claims, or controversies
         concerning the lawfulness or reasonableness of any act, or exercise of
         any right, concerning any Collateral, including any claim to rescind,
         reform, or otherwise modify any agreement relating to the Collateral,
         shall also be arbitrated, provided however that no arbitrator shall
         have the right or the power to enjoin or restrain any act of any
         party. Judgment upon any award rendered by any arbitrator may be
         entered in any court having jurisdiction. Nothing in this Guaranty
         shall preclude any party from seeking equitable relief from a court of
         competent jurisdiction. The statute of limitations, estoppel, waiver,
         laches, and similar doctrines which would otherwise be applicable in
         an action brought by a party shall be applicable in any arbitration
         proceeding, and the commencement of an arbitration proceeding shall be
         deemed the commencement of an action for these purposes. The Federal
         Arbitration Act shall apply to the construction, interpretation, and
         enforcement of this arbitration provision.

         ATTORNEYS' FEES; EXPENSES. Guarantor agrees to pay upon demand all of
         Lender's costs and expenses, including attorneys' fees and Lender's
         legal expenses, incurred in connection with the enforcement of this
         Guaranty. Lender may pay someone else to help


<PAGE>   11

         enforce this Guaranty, and Guarantor shall pay the costs and expenses
         of such enforcement. Costs and expenses include all costs and expenses
         of collection, including fifteen percent (15%) of the principal plus
         accrued interest as attorneys' fees, if any sums owing under this
         Guaranty are collected by or through an attorney-at-law, whether or not
         there is a lawsuit, including attorneys' fees and legal expenses for
         bankruptcy proceedings (and including efforts to modify or vacate any
         automatic stay or injunction), appeals, and any anticipated
         post-judgment collection services. Guarantor also shall pay all court
         costs and such additional fees as may be directed by the court.

         NOTICES. All notices required to be given by either party to the other
         under this Guaranty shall be in writing, may be sent by telefacsimile
         (unless otherwise required by law), and, except for revocation notices
         by Guarantor, shall be effective when actually delivered or when
         deposited with a nationally recognized overnight courier, or when
         deposited in the United States mail, first class postage prepaid,
         addressed to the party to whom the notice is to be given at the address
         shown above or to such other addresses as either party may designate to
         the other in writing. All revocation notices by Guarantor shall be in
         writing and shall be effective only upon delivery to Lender as provided
         above in the Section titled "DURATION OF GUARANTY." It there is more
         than one Guarantor, notice to any Guarantor will constitute notice to
         all Guarantors. For notice purposes, Guarantor agrees to keep Lender
         informed at all times of Guarantor's current address.

         INTERPRETATION. In all cases where there is more than one Borrower or
         Guarantor, then all words used in this Guaranty in the singular shall
         be deemed to have been used in the plural where the context and
         construction so require; and where there is more than one Borrower
         named in this Guaranty or when this Guaranty is executed by more than
         one Guarantor, the words "Borrower" and "Guarantor" respectively shall
         mean all and any one or more of them. The words "Guarantor,"
         Borrower," and "Lender" include the heirs, successors, assigns, and
         transferees of each of them. Caption headings in this Guaranty are for
         convenience purposes only and are not to be used to interpret or
         define the provisions of this Guaranty. If a court of competent
         jurisdiction finds any provision of this Guaranty to be invalid or
         unenforceable as to any person or circumstance, such finding shall not
         render that provision invalid or unenforceable as to any other persons
         or circumstances, and all provisions of this Guaranty in all other
         respects shall remain valid and enforceable. If any one or more of
         Borrower or Guarantor are corporations or partnerships, it is not
         necessary for Lender to inquire into the powers of Borrower or
         Guarantor or of the officers, directors, partners, or agents acting or
         purporting to act on their behalf, and any Indebtedness made or
         created in reliance upon the professed exercise of such powers shall
         be guaranteed under this Guaranty.

         WAIVER. Lender shall not be deemed to have waived any rights under
         this Guaranty unless such waiver is given in writing and signed by
         Lender. No delay or omission on the part of Lender in exercising any
         right shall operate as a waiver of such right or any other right. A
         waiver by Lender of a provision of this Guaranty shall not prejudice
         or constitute a waiver of Lender's right otherwise to demand strict
         compliance with that provision or any other provision of this
         Guaranty. No prior waiver by Lender, nor any course of dealing between
         Lender and Guarantor, shall constitute a waiver of any of Lender's
         rights or of any of Guarantor's obligations as to any future
         transactions. Whenever the consent of Lender is required under this
         Guaranty, the granting of such


<PAGE>   12

         consent by Lender in any instance shall not constitute continuing
         consent to subsequent instances where such consent is required and in
         all cases such consent may be granted or withheld in the sole
         discretion of Lender.

EACH UNDERSIGNED GUARANTOR ACKNOWLEDGES HAVING READ ALL THE PROVISIONS OF THIS
GUARANTY AND AGREES TO ITS TERMS. IN ADDITION, EACH GUARANTOR UNDERSTANDS THAT
THIS GUARANTY IS EFFECTIVE UPON GUARANTOR'S EXECUTION AND DELIVERY OF THIS
GUARANTY TO LENDER AND THAT THE GUARANTY WILL CONTINUE UNTIL TERMINATED IN THE
MANNER SET FORTH IN THE SECTION TITLED "DURATION OF GUARANTY." NO FORMAL
ACCEPTANCE BY LENDER IS NECESSARY TO MAKE THIS GUARANTY EFFECTIVE. THIS
GUARANTY IS DATED MARCH 6, 2000.

IN WITNESS WHEREOF, THIS GUARANTY HAS BEEN SIGNED AND SEALED BY THE
UNDERSIGNED, WHO ACKNOWLEDGES A COMPLETED COPY HEREOF.


X                                           (SEAL)
 -------------------------------------------
     Guarantor


Signed, Sealed and Delivered in the presence of:


X                                           (SEAL)
 -------------------------------------------
     Unofficial Witness



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

Notary Public,_______________________ County


                  (NOTARY SEAL)

My Commission expires:______________________

LENDER:

The Bankers Bank

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


<PAGE>   13


                             SCHEDULE OF GUARANTORS



James O. Andrews

James H. Daws

James E. Hinshaw, Sr.

Donald F. Jackson

Lewis A. Massey

Tyler C. McCain

M. Lauch McKinnon

D. Alan Najjar

D. Arnold Tillman, Jr.

Jeffrey S. Tucker


<PAGE>   14

                                          FORM OF CORPORATE RESOLUTION TO BORROW
<TABLE>
<CAPTION>
----------------- ------------- ------------- -------------- --------- ----------- ------------ ------------ --------------
     PRINCIPAL       LOAN DATE     MATURITY       LOAN NO.      CALL    COLLATERAL    ACCOUNT      OFFICER       INITIALS
<S>               <C>           <C>           <C>            <C>       <C>         <C>          <C>
    $750,000.00     03-06-2000    06-28-2000     4021395101                           4021395        JKG
---------------------------------------------------------------------------------------------------------------------------
References in the shaded area are for Lender's use only and do not limit the applicability of this document to any
particular loan or item
---------------------------------------------------------------------------------------------------------------------------
</TABLE>

BORROWER:    SOUTHERNBANK HOLDINGS, INC.        LENDER:   THE BANKERS BANK
             P.O. BOX 967                                 2410 PACES FERRY ROAD
             BUFORD, GA  30515-0967                       600 PACES SUMMIT
                                                          ATLANTA, GA  30339

===============================================================================

I, THE UNDERSIGNED SECRETARY OR ASSISTANT SECRETARY OF SOUTHERNBANK HOLDINGS,
INC. (THE "CORPORATION"), HEREBY CERTIFY THAT the Corporation is organized and
existing under and by virtue of the laws of the State of Georgia as a
corporation for profit, with its principal office at P.O. Box 967, BUFORD, GA
30515-0967, and is duly authorized to transact business in the State of
Georgia.

I FURTHER CERTIFY that at a meeting of the Directors of the Corporation, duly
called and held on __________________________, at which a quorum was present
and voting, or by other duly authorized corporate action in lieu of a meeting,
the following resolutions were

BE IT RESOLVED, that any TWO (2) of the following named officers, employees, or
agents of this Corporation, whose actual signatures are shown below:

<TABLE>
<CAPTION>
     NAMES                    POSITIONS           ACTUAL SIGNATURES
     -----                    ---------           -----------------
     <S>                      <C>                 <C>
     D. Arnold Tillman        CEO                 x
                                                   -----------------------

     M. Lauch McKinnon        President           x
                                                   -----------------------
</TABLE>

acting for and on behalf of the Corporation and as its act and deed be, and
they hereby are, authorized and empowered:

     BORROW MONEY. To borrow from time to time from The Bankers Bank
     ("Lender"), on such terms as may be agreed upon between the Corporation
     and Lender, such sum or sums OF money as in their judgment should be
     borrowed; however, not exceeding at any one time the amount OF SEVEN
     HUNDRED FIFTY THOUSAND & 00/100 DOLLARS ($750,000.00), in addition to such
     sum or sums of money as may be currently borrowed by the Corporation from
     Lender.

     EXECUTE NOTES. To execute and deliver to Lender the promissory note or
     notes, or other evidence of credit accommodations of the Corporation, on
     Lender's forms, at such rates of interest and on such terms as may be
     agreed upon, evidencing the sums of money so borrowed or any indebtedness
     of the Corporation to Lender, and also to execute and deliver to Lender
     one or more renewals, extensions, modifications, refinancings,
     consolidations, or substitutions for one or more of the notes, any portion
     of the notes, or any other evidence of credit accommodations.


<PAGE>   15

     GRANT SECURITY. To mortgage, pledge, transfer, endorse, hypothecate, or
     otherwise encumber and deliver to Lender, as security for the payment of
     any loans or credit accommodations so obtained, any promissory notes so
     executed (including any amendments to or modifications, renewals, and
     extensions of such promissory notes), or any other or further indebtedness
     of the Corporation to Lender at any time owing, however the same may be
     evidenced, any property now or hereafter belonging to the Corporation or
     in which the Corporation now or hereafter may have an interest, including
     without limitation all real property and all personal property (tangible
     or intangible) of the Corporation. Such property may be mortgaged,
     pledged, transferred, endorsed, hypothecated, or encumbered at the time
     such loans are obtained or such indebtedness is incurred, or at any other
     time or times, and may be either in addition to or in lieu of any property
     theretofore mortgaged, pledged, transferred, endorsed, hypothecated, or,
     encumbered.

     EXECUTE SECURITY DOCUMENTS. To execute and deliver to Lender the forms of
     mortgage, deed of trust, pledge agreement, hypothecation agreement, and
     other security agreements and financing statements which may be submitted
     by Lender, and which shall evidence the terms and conditions under and
     pursuant to which such liens and encumbrances . or any of them, are given;
     and also to execute and deliver to Lender any other written instruments,
     any chattel paper, or any other collateral, of any kind or nature, which
     they may in their discretion deem reasonably necessary or proper in
     connection with or pertaining to the giving of the liens and encumbrances.
     Notwithstanding the foregoing, any one of the above authorized persons may
     execute, deliver, or record financing statements.

     NEGOTIATE ITEMS. To draw, endorse, and discount with Lender all drafts,
     trade acceptances, promissory notes, or other evidences of indebtedness
     payable to or belonging to the Corporation in which the Corporation may
     have an interest, and either to receive cash for the same or to cause such
     proceeds to be credited to the account of the Corporation with Lender, or
     to cause such other disposition of the proceeds derived therefrom as they
     may deem advisable.

     FURTHER ACTS. in the case of lines of credit, to designate additional or
     alternate individuals as being authorized to request advances thereunder,
     and in all cases, to do and perform such other acts and things, to pay any
     and all fees and costs, and to execute and deliver such other documents
     and agreements as they may in their discretion deem reasonably necessary
     or proper in order to carry into effect the provisions of these
     Resolutions. The following person or persons currently are authorized to
     request advances and authorize payments under the line OF credit until
     Lender receives written notice of revocation of their authority: D.
     Arnold Tillman, Tyler C. McCain and M. Lauch McKinnon.

BE IT FURTHER RESOLVED, that any and all acts authorized pursuant to these
Resolutions and performed prior to the passage of these Resolutions are hereby
ratified and approved, that these Resolutions shall remain in full force and
effect and Lender may rely on these Resolutions until written notice of their
revocation shall have been delivered to and received by Lender. Any such notice
shall not affect any OF the Corporation's agreements or commitments in effect
at the time notice is given.


<PAGE>   16

BE IT FURTHER RESOLVED, that the Corporation will notify Lender in writing at
Lender's address shown above (or such other addresses as Lender may designate
from time to time) prior to any (a) change in the name of the Corporation, (b)
change in the assumed business name(s) of the Corporation, (c) change in the
management of the Corporation,, (d) change in the authorized signer(s), (e)
conversion of the Corporation to A new or different type of business entity, or
(f) change in any other aspect of the Corporation that directly or indirectly
relates to any agreements between the Corporation and Lender. No change in the
name of the Corporation will take effect until after Lender has been notified.

I FURTHER CERTIFY that the officers, employees, and agents named above are duly
elected, appointed, or employed by or for the Corporation, as the case may be,
and occupy the positions set opposite their respective names; that the
foregoing Resolutions now stand of record on the books of the Corporation; and
that the Resolutions are in full force and effect and have not been modified or
revoked in any manner whatsoever. The Corporation has no corporate seal, and
therefore, no seal is affixed to this certificate,

IN TESTIMONY WHEREOF, I HAVE HEREUNTO SET MY HAND AND SEAL ON MARCH 6, 2000 AND
ATTEST THAT THE SIGNATURES SET OPPOSITE THE NAMES LISTED ABOVE ARE THEIR
GENUINE SIGNATURES.

                                             CERTIFIED TO AND ATTESTED BY:


                                            X                            (SEAL)
                                             ----------------------------

                                            X                            (SEAL)
                                             ----------------------------