Document:

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                                 EXHIBIT 10(k)
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                                                                   Exhibit 10(k)

                                 FIRST AMENDMENT
                          TO SOUTHSIDE BANCSHARES CORP.
                    DEFERRED COMPENSATION PLAN FOR DIRECTORS

         This First Amendment (hereinafter referred to as the "Amendment") is
entered into this 1st day of December, 1999, the effective date, between
SOUTHSIDE BANCSHARES CORP., with its principal place of business in St. Louis,
Missouri (the "Company"), and NORVILLE K. MCCLAIN, a director of the Company
(hereinafter referred to as the "Director").

         WHEREAS, the Director has served on the Board of Directors of the
Company (hereinafter referred to as the "Board"), and the Board wishes to
provide additional incentives for the Director's continued service; and

         WHEREAS, the Director has contributed to the success and profitability
of the Company and is expected to continue such contribution; and

         WHEREAS, the Director and the Company have previously entered into a
plan entitled Southside Bancshares Corp. Deferred Compensation Plan for
Directors, dated April 25, 1996, which includes an agreement entitled the
Southside Bancshares Corp. Deferred Compensation Plan for Directors
Participation Agreement executed by the Director (hereinafter collectively
referred to as the "Previous Plan"), which provided that the Company would
provide certain benefits to the Director upon his retirement; and

         WHEREAS, the Company and the Director desire to set forth their
Amendment to the Previous Plan as to fees the Director has already deferred and
the continued deferral of a portion of the Director's fees as a deferred
compensation plan and to provide certain additional benefits in the case of the
Director's death while serving as a Director of the Company; and

         WHEREAS, the Company and the Director desire to provide the Director,
in lieu of Director's fees already deferred and the deferral of annual
Director's fees of Thirty Five Thousand Four Hundred and 00/100 Dollars
($35,400.00) per year for the next seven (7) years, as compensation for his
services to the Company, a post-retirement income or a pre-retirement death
benefit to his beneficiary.

         NOW, THEREFORE, in consideration of the mutual agreements contained
herein, the Company and the Director hereby amend and restate the Previous Plan
as follows:

         1. Director agrees that the benefits provided under this Amendment are
in lieu of the benefits accumulated to the Director under the Previous Plan.

         2. The liability existing on the financial records on the Company
("Rollover Balance") under the Previous Plan as of the effective date of this
Amendment will be included in the Director's Account as hereinafter defined.

         3. Director revokes all prior deferral elections and agrees to a
reduction of the current payment of his compensation for service on the Board by
Thirty Five Thousand Four Hundred and
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00/100 Dollars ($35,400.00) per year, annually deferred in twelve (12)
substantially equal monthly installments, for a period of seven (7) years, or
such other amount as shall be elected by the Director in a signed writing
delivered to the Company, and to defer receipt of such amount until paid
pursuant to later provisions of this Amendment. Compensation reductions under
this Amendment shall cease at the earlier of the end of the deferral period or
when said Director attains age seventy-seven (77). The Director may change the
amount of or suspend future deferrals with respect to fees and retainers earned
for calendar years commencing after the date of change or suspension as he may
specify by written notice to the Company. Following any such suspension, the
Director may make a new election to again become a deferral participant;
however, the election to defer shall be irrevocable for the particular year, and
must be made prior to the beginning of the calendar year.

         4. The Company will record amounts deferred pursuant to paragraphs 2
and 3 and amounts credited pursuant to paragraph 5 in a separate account
(hereinafter referred to as the "Account") in the financial records of the
Company.

         5. Until the Director attains age seventy-seven (77), the Company will
credit interest compounded monthly to the Account as follows: subject to a
minimum annual rate of six percent (6%) and a maximum annual rate of fifteen
percent (15%), a rate equal to the annual percentage increase (the "Annual
Rate") of the stock price of Southside Bancshares Corp (the "Stock Price"). The
annual percentage increase of the Stock Price shall be initially determined
utilizing a fraction that has a numerator calculated by subtracting the closing
bid price one year prior to the effective date of this Amendment from the
closing bid price on the effective date of this Amendment and a denominator
equal to the closing bid price one year prior to the effective date of this
Amendment. For each subsequent year that this Amendment is effective, the Annual
Rate will be determined utilizing a fraction that has a numerator calculated by
subtracting the closing bid price one year prior to each anniversary of
effective date of this Amendment from the closing bid price on each anniversary
of effective date of this Amendment and a denominator equal to the closing bid
price one year prior to the anniversary of effective date of this Amendment.
Notwithstanding the above, at any time the Director fails to defer a monthly
amount under paragraph 3, the annual interest rate the Company will credit the
Account under this paragraph will be six percent (6%), compounded monthly for
the period the Director makes no deferral. Once the Director attains age
seventy-seven (77) or the service of the Director is terminated and payments
from the Account continue to be deferred, the Company will credit interest
compounded monthly to the Account at a rate of six percent (6%) until the
balance of the Account is fully paid.

         6. The Account will be unfunded and no assets of the Company will be
segregated with respect to the Account. Further, the Account shall be kept only
for purposes of its identification on the books and records of the Company as a
liability of the Company to the Director, and the Account will be subject to the
claims of general creditors of the Company.

         7. Amounts held in the Account or a death benefit will be payable as
indicated in Paragraph 8 upon the first to occur of the following events:

                  (a) termination of the Director's membership on the Board of
         the Company other than by death; or

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                  (b) termination of this Agreement pursuant to Paragraph 17; or

                  (c) the occurrence of the Director's 77th birthday; or

                  (d) the death of the Director.

The Company shall only have the obligation to complete making payments under
Paragraph 8 to the Director, his/her designated beneficiary, or the estate of
the designated beneficiary pursuant to the applicable subparagraph above.

8.

                  a. If payment is to be made due to the occurrence of an event
described in 7(a) or in 7(b), subject to provisions of paragraph 9, an amount
equal to the balance in the Account shall be paid to the Director in one lump
sum not later than sixty (60) days following the occurrence of the event.

                  b. If payment is to be made due to the occurrence of the event
described in 7(c), the balance in the Account shall be paid to the Director in
substantially equal monthly installments over a thirty-six (36) month period
commencing on the first day of the month following the Director's birthday.

                  c. If payment is to be made due to the occurrence of the event
described in 7(d), the amount payable to the Director's beneficiary shall be the
monthly amount stated in Addendum A multiplied by a fraction the numerator of
which is equal to the sum of: (i) the Rollover Balance, including interest
credited to this amount through the date of the Director's death pursuant to
paragraph 5 of this Amendment; (ii) the amount actually deferred under this
Amendment until the Director's death, including the interest credited to these
deferrals through the date of the Director's death pursuant to paragraph 5 of
this Amendment; (iii) the projected amounts that would have been deferred from
the date of the Director's death through the date the Director would have
attained age seventy-seven (77), based on the Director's elected deferral amount
in effect on the date of the Director's death; and (iv) the interest that would
have been credited to the amounts in (i), (ii), and (iii) immediately above
pursuant to paragraph 5 from the date of the Director's death until the date the
Director would have reached age 77 assuming an Annual Rate that would equal the
average annual interest credited to the Director's Account from the effective
date of this Amendment through the Director's death or an Annual Rate equal to
six percent (6%) if the Director was not making monthly deferrals at the date of
the Director's death; and the denominator of which shall equal the sum of the
Rollover Balance and the projected total deferral that would have occurred if
the Director would have deferred the amount set forth in paragraph 3 from the
date of this Amendment through the date the Director would have attained age
seventy-seven (77), including the maximum annual interest credited under
paragraph 5 of this Amendment to the Rollover balance and to the projected
deferrals under paragraph 3; provided, however, under no circumstances shall the
monthly benefit be greater than that stated in Addendum A. Payments to the
Director's designated beneficiary shall begin the first day of the month
following the month the Director would have attained age seventy-seven (77).

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         9. If payment is to be made under subparagraph 7 (a) and the Director's
termination is due to disability covered under a disability insurance policy,
the Company may, in its sole discretion, defer payment until payments under the
disability policy cease.

         10. In the event the Director should die before receiving the payment
due under subparagraph 8(a) or the payments due under subparagraph 8(b), the
remaining payment or payments, as the case may be, shall be paid to the
Director's designated beneficiary.

         11. If the Director's designated beneficiary dies before receiving all
payments due, the Company shall pay the remaining payments, in the same form of
pay out as the designated beneficiary has been receiving or is to receive, to
the revocable trust of the Designated beneficiary and, if none, to the estate of
the designated beneficiary.

         12. Director may request in a signed writing delivered to the Board,
that the Company pay a hardship distribution to the Director from amounts held
in the Account. Hardship means an unforeseen event or situation that creates an
extraordinary financial need that cannot reasonably be met by other resources of
the Director. The Board shall elect in its sole discretion, without
participation of the Director making the request, whether or not to grant such
request.

         13. Any amounts payable to the Director's designated beneficiary
pursuant to this Amendment will be paid to the beneficiary designated by the
Director in a signed writing delivered to the Company. Director has the right to
change his beneficiary designation by delivering to the Company a subsequent
signed writing. If Director does not designate a beneficiary in the manner
described in this paragraph 13, or if the designated beneficiary has predeceased
the Director, then amounts payable hereunder will be payable first to the
Director's surviving spouse; and if the Director has no surviving spouse, then
such amounts will then be payable to the Director's estate or as provided by a
decree of distribution or other proper order by the court having jurisdiction of
such estate. No one other than the Director shall have any right to designate a
beneficiary.

         14. The right to receive payments under this Amendment shall not be
assigned or encumbered, or subject to anticipation, garnishment, attachment, or
any other legal process of creditors of the Director or of any designated
beneficiary. If the Director or a designated beneficiary attempts to assign such
right, the Board, in its sole discretion, may suspend, reduce or terminate any
or all rights created by this Amendment as to the Director or the designated
beneficiary attempting said assignment.

         15. Nothing in this Amendment shall be construed as giving the Director
the right to be retained on the Company's Board. The Director shall remain
subject to discharge at any time and to the same extent as if this Amendment had
not been executed.

         16. The Company does not assure or guarantee the tax consequences of
payments provided hereunder or matters beyond its control, and the Director
certifies that his decision to reduce and defer receipt of his compensation is
not due to any reliance upon financial, tax or legal advice given by the Company
or any of its employees.

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         17. This Amendment may be amended or terminated at any time by the
Company in writing; however, no amendment or termination may reduce amounts
payable to Director or his designated beneficiary below the then Account
balance, without such person's written consent.

         18. The Board upon ninety (90) days advance written notice to the
Director may terminate this Amendment and, in the event of such termination,
shall pay an amount equal to the then Account balance in a lump sum to the
Director within sixty (60) days following such termination.

         19. While the Company intends that this Plan will result in the
deferral of the imposition of a federal income tax on the funds credited
hereunder until such time as they actually be paid to a Director, nothing herein
shall be construed as a promise, guarantee or other representation by the
Company of such tax effect nor, without limitation, shall the Company be liable
for any taxes, penalties or other amounts incurred by Directors in the event it
is determined by applicable authorities that such deferral was not accomplished,
and the Director should consult his or her own tax advisor(s) to determine the
tax consequences in his or her specific case.

         IN WITNESS WHEREOF, the parties hereof have entered into this Amendment
at St. Louis, Missouri, as of the date first above written.

                           SOUTHSIDE BANCSHARES CORP.

                           BY:      /S/ THOMAS M. TESCHNER
                           ITS:      PRESIDENT & CEO

                           DIRECTOR:

                               /S/ NORVILLE K. MCCLAIN
                           NORVILLE K. MCCLAIN

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                             BENEFICIARY DESIGNATION

I, Norville K. McClain, designate the following as beneficiary of any death
benefits payable under the Second Amendment to Southside Bancshares Corp.
Deferred Compensation Plan for Directors myself and Southside Bancshares Corp.:

 Primary Beneficiary

 Name             Dawn L. McClain                  Relationship      Wife

 Address          13629 Klondike Road              DeSoto, MO 63020

Contingent Beneficiary (to receive the benefits if there is no surviving Primary
Beneficiary)

 Name                                     Relationship

 Address

NOTE: TO NAME A TRUST AS BENEFICIARY, PLEASE PROVIDE THE NAME OF THE TRUSTEE AND
THE EXACT DATE OF THE TRUST AGREEMENT.

I understand that I may change these beneficiary designations by filing a new
written designation with the Company. I further understand that the designations
will be automatically revoked if the beneficiary predeceases me, or, if I have
named my spouse as beneficiary, in the event of the dissolution of our marriage.
I further understand that this beneficiary designation revokes all prior
beneficiary designations applicable to this Amendment.

                                           Consented to by Director's spouse:
Director's Signature:                      Spouse's Signature:

  /s/ Norville K. McClain
NORVILLE K. MCCLAIN

Date: December 23, 1999                    Date:

Accepted by the Company this 23rd day of December, 1999.

By:      /s/ Thomas M. Teschner
Title:   President
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                                   ADDENDUM A

Eighteen Thousand Six Hundred Seventy Two and 67/100 dollars ($18,672.67) per
month for thirty six (36) months.

ADDENDUM A - PAGE SOLO<PAGE>   1

                                 EXHIBIT 10(l)
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                                                                   Exhibit 10(l)

                            SOUTHSIDE BANCSHARES CORP
                             SPLIT DOLLAR AGREEMENT

       THIS AGREEMENT is made and entered into this 1st day of December, 1999,
by and between SOUTHSIDE BANCSHARES CORP a bank holding company located in St.
Louis, Missouri (the "Company"), and the THOMAS M. TESCHNER IRREVOCABLE
INSURANCE TRUST dated November 18, 1999 (the "Trust"). This Agreement shall
append the Split Dollar Endorsement entered into on December 1, 1999, or as
subsequently amended, by and between the aforementioned parties.

                                  INTRODUCTION

       WHEREAS, THOMAS M. TESCHNER (the "Executive") has contributed
substantially to the success of the Company. The Company, as a fringe benefit,
is willing to divide the death proceeds of a life insurance policy on the
Executive's life. The Company will pay life insurance premiums from its general
assets.

                                   ARTICLE 1
                               GENERAL DEFINITIONS

The following terms shall have the meanings specified:

         1.1. "Annual Tax Amount" shall mean the individual income tax (computed
using the highest marginal state and federal individual income tax rates for the
year the income is imputed) attributable to the annual imputed income described
in Section 3.2 increased by eight (8%) compounded annually during the
Executive's employment.

         1.2. "Insurer" means each of the following: Alexander Hamilton Life
Insurance Company.

         1.3. "Policy" means each of the following: insurance policy #AH5061692
issued by Alexander Hamilton Life Insurance Company.

         1.4. "Insured" means the Executive.

         1.5. "Normal Retirement Date" means the Executive's 65th birthday.

         1.6. "Termination of Employment" means the Executive ceasing to be
employed by the Company for any reason whatsoever, other than by reason of an
approved leave of absence.
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         1.7. "Trustee" refers to the trustee or trustees of the Trust.

         1.8. "Shareholder" means the existing owners of all issued and
outstanding stock of the Company as of the date this Agreement is signed.

                                   ARTICLE 2
                           POLICY OWNERSHIP/INTERESTS

         2.1. Company Ownership. The Company is the sole owner of the Policy and
shall have the right to exercise all incidents of ownership. The Company shall
be the direct beneficiary of an amount of death proceeds, less policy loans to
the Company, if any, in excess of: (i) prior to or on the Normal Retirement
Date, $3,474,940.00; and (ii) after the Normal Retirement Date amounts set forth
on the attached Schedule A calculated in accordance with Schedule A.

         2.2. Trust's Interest. The Trust shall be the beneficiary of an amount
equal to: (i) prior to or on the Normal Retirement Date, $3,474,940.00; and (ii)
after the Normal Retirement Date amounts set forth on the attached Schedule A
calculated in accordance with Schedule A. The Trust shall also have the right to
elect and change settlement options that may be permitted. Provided, however,
the Executive, the Trust or its transferee beneficiary shall have no rights or
interests in the Policy with respect to that portion of the death proceeds
designated in this section 2.2 upon the Executive's Termination of Employment
prior to Normal Retirement Age.

         2.3. Option to Purchase. Prior to the Executive's Normal Retirement
Date, the Company shall not sell, surrender or transfer ownership of the Policy
while this Agreement is in effect without first giving the Trust or the Trust's
transferee the option to purchase the Policy for a period of sixty (60) days
from written notice of such intention. The purchase price shall be an amount
equal to the cash surrender value of the Policy.

         2.4. Comparable Coverage. Notwithstanding anything in this Agreement to
the contrary, on or after the Executive's Normal Retirement Date, the Company
shall maintain the Policy in full force and effect and in no event shall the
Company amend, terminate or otherwise abrogate the Trust's interest in the
Policy, unless the Company replaces the Policy with a comparable insurance
policy to cover the benefit provided under this Agreement.

         2.5. Termination of Employment Prior to Normal Retirement Date. Should
Termination of Employment occur prior to the Normal Retirement Date, the Company
shall pay to the Executive an amount equal to the sum of each Annual Tax Amount
divided by 1.00 minus the highest marginal combined state and federal individual
income tax rates as of the date of Termination of Employment. The tax rates used
to determine the amount under this section 2.5 shall be the rates in effect for
the year Termination of Employment occurs. The Company shall pay this amount
within sixty (60) days from the date of Termination of Employment.

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         2.6. Parachute Payment. If it is determined that any portion of the
benefit payment to the Executive under Section 2.5 constitutes a parachute
payment under Section 280G of the Code subject to the excise tax of Section 4999
of the Code, the Executive shall be entitled to receive from the Company a lump
sum cash payment sufficient to place the Executive in the same net after tax
position that the Executive would have been in had such payment not been subject
to such excise tax; provided, however, the Executive shall be entitled to a
payment under this Section 2.6 only to the extent that the Executive is not
entitled to an equivalent payment under any other agreement.

                                   ARTICLE 3
                                    PREMIUMS

         3.1. Premium Payment. The Company shall pay any premiums due on the
Policy.

         3.2. Imputed Income. The Company shall impute income annually to the
Executive in an amount equal to the current term rate for the Executive's age
multiplied by the aggregate death benefit payable to the Executive's
beneficiary. The "current term rate" is the minimum amount required to be
imputed under Revenue Rulings 64-328 and 66-110, or any subsequent applicable
authority.

                                   ARTICLE 4
                                   ASSIGNMENT

         The Trust may assign without consideration all of its interests in the
Policy and in this Agreement to any person, entity or other trust. In the event
the Trust shall transfer all of its interest in the Policy, then all of the
Trust's interest in the Policy and in the Agreement shall be vested in its
transferee, who shall be substituted as a party hereunder and the Trust shall
have no further interest in the Policy or in this Agreement.

                                   ARTICLE 5
                                     INSURER

         The Insurer shall be bound only by the terms of the Policy. Any
payments the Insurer makes or actions it takes in accordance with the Policy
shall fully discharge it from all claims, suits and demands of all entities or
persons. The Insurer shall not be bound by or be deemed to have notice of the
provisions of this Agreement.

                                   ARTICLE 6
                                    EXECUTIVE

         The Executive is not a party to this Agreement or to the corresponding
Endorsement. Except as otherwise provided herein, the Executive shall have no
rights, title or interest hereunder.

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                                   ARTICLE 7
                                CLAIMS PROCEDURE

         7.1. Claims Procedure. The Company shall notify the Trust, the Trust's
transferee or beneficiary, or any other party who claims a right to an interest
under this Agreement (the "Claimant') in writing, within 90 days of Claimant's
written application for benefits, of his or her eligibility or ineligibility for
benefits under this Agreement. If the Company determines that the Claimant is
not eligible for benefits or full benefits, the notice shall set forth (1) the
specific reasons for such denial, (2) a specific reference to the provisions of
this Agreement on which the denial is based, (3) a description of any additional
information or material necessary for the Claimant to perfect his or her claim,
and a description of why it is needed, and (4) an explanation of this
Agreement's claims review procedure and other appropriate information as to the
steps to be taken if the Claimant wishes to have the claim reviewed. If the
Company determines that there are special circumstances requiring additional
time to make a decision, the Company shall notify the Claimant of the special
circumstances and the date by which a decision is expected to be made, and may
extend the time for up to an additional 90 days.

         7.2. Review Procedure. If the Claimant is determined by the Company not
to be eligible for benefits, or if the Claimant believes that he or she is
entitled to greater or different benefits, the Claimant shall have the
opportunity to have such claim reviewed by the Company by filing a petition for
review with the Company within 60 days after receipt of the notice issued by the
Company. Said petition shall state the specific reasons which the Claimant
believes entitle him or her to benefits or to greater or different benefits.
Within 60 days after receipt by the Company of the petition, the Company shall
afford the Claimant (and counsel, if any) an opportunity to present his or her
position to the Company verbally or in writing, and the Claimant (or counsel)
shall have the right to review the pertinent documents. The Company shall notify
the Claimant of its decision in writing within the 60-day period, stating
specifically the basis of its decision, written in a manner calculated to be
understood by the Claimant and the specific provisions of this Agreement on
which the decision is based. If, because of the need for a hearing, the 60-day
period is not sufficient, the decision may be deferred for up to another 60 days
at the election of the Company, but notice of this deferral shall be given to
the Claimant.

                                   ARTICLE 8
                           AMENDMENTS AND TERMINATION

         This Agreement may be amended or terminated only by a written agreement
signed by the Company and the Trustee. However, unless otherwise agreed to by
the Company and the Trust, subject to section 2.3, this Agreement will
automatically terminate upon the Executive's Termination of Employment prior to
Normal Retirement Age.

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                                   ARTICLE 9
                                  MISCELLANEOUS

         9.1. Binding Effect. This Agreement shall bind the Trust and the
Company, their beneficiaries, survivors, executors, administrators and
transferees, and any Policy beneficiary.

         9.2. No Guarantee of Employment. This Agreement is not an employment
policy or contract. It does not give the Executive the right to remain an
employee of the Company, nor does it interfere with the Company's right to
discharge the Executive. It also does not require the Executive to remain an
employee nor interfere with the Executive's right to terminate employment at any
time.

         9.3. Creditor Claims. The Policy or any comparable policy subject to
this agreement are general assets of the Company and shall be subject to the
claims of the Company's creditors.

         9.4. Applicable Law. The Agreement and all rights hereunder shall be
governed by and construed according to the laws of the State of Missouri, except
to the extent preempted by the laws of the United States of America.

         9.5. Reorganization. The Company shall not merge or consolidate into or
with another company, or reorganize, or sell substantially all of its assets to
another company, firm or person unless such succeeding or continuing company,
firm or person agrees to assume and discharge the obligations of the Company.

         9.6. Notice. Any notice, consent or demand required or permitted to be
given under the provisions of this Split Dollar Agreement by one party to
another shall be in writing, shall be signed by the party giving or making the
same, and may be given either by delivering the same to such other party
personally, or by mailing the same, by United States certified mail, postage
prepaid, to such party, addressed to his or her last known address as shown on
the records of the Company. The date of such mailing shall be deemed the date of
such mailed notice, consent or demand.

         9.7. Entire Agreement. This Agreement constitutes the entire agreement
between the Company and the Trust as to the subject matter hereof. No rights are
granted to the Trust by virtue of this Agreement other than those specifically
set forth herein.

         9.8. Administration. The Company shall have powers that are necessary
to administer this Agreement, including but not limited to:

                  (a) Interpreting the provisions of the Agreement;

                  (b) Establishing and revising the method of accounting for the
         Agreement;

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                  (c) Maintaining a record of benefit payments; and

                  (d) Establishing rules and prescribing any forms necessary or
         desirable to administer the Agreement.

         9.9. Named Fiduciary. The Company shall be the named fiduciary and plan
administrator under the Agreement. The named fiduciary may delegate to others
certain aspects of the management and operation responsibilities of the plan
including the employment of advisors and the delegation of ministerial duties to
qualified individuals

       IN WITNESS WHEREOF, the parties have executed this Agreement the day and
year first above written.

TRUST:                                         COMPANY:
THOMAS M. TESCHNER                             SOUTHSIDE BANCSHARES CORP
IRREVOCABLE INSURANCE TRUST

BY      /S/ JOHN K. PRUELLAGE                  BY    /S/ JOSEPH W. POPE
     CO-TRUSTEE                                TITLE CHIEF FINANCIAL OFFICER

BY
     CO-TRUSTEE

                                       6
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                         SPLIT DOLLAR POLICY ENDORSEMENT
                SOUTHSIDE BANCSHARES CORP SPLIT DOLLAR AGREEMENT

Policy No. AH506 1692                            Insured: THOMAS M. TESCHNER

Supplementing and amending the application for insurance to Alexander Hamilton
Life Insurance Company ("Insurer") on November 24, 1999, the applicant requests
and directs that:

                                  BENEFICIARIES

         1. SOUTHSIDE BANCSHARES CORP. a bank holding company located in St.
Louis, Missouri (the "Company"), shall be the direct beneficiary of an amount of
death proceeds, less policy loans to the Company, if any, in excess of: (i)
prior to or on the Normal Retirement Date, $3,474,940.00; and (ii) after the
Normal Retirement Date amounts set forth on the attached Schedule A calculated
in accordance with Schedule A.

         2. Subject to the provisions of paragraph (5) below, the THOMAS M.
TESCHNER IRREVOCABLE INSURANCE TRUST (the "Trust") or the Trust's transferee
shall be the beneficiary of an amount equal to: (i) prior to or on the Normal
Retirement Date, $3,474,940.00; and (ii) after the Normal Retirement Date
amounts set forth on the attached Schedule A calculated in accordance with
Schedule A.

                                    OWNERSHIP

         3. The Owner of the policy shall be the Company. The Owner shall have
all ownership rights in the Policy except as may be specifically granted to the
Trust or its transferee in paragraph (4) of this endorsement.

         4. The Trust or its transferee shall have the right to assign all
rights and interests in the Policy with respect to that portion of the death
proceeds designated in paragraph (2) of this endorsement, and to exercise all
settlement options with respect to such death proceeds.

         5. Notwithstanding the provisions of paragraph (4) above, the Trust or
its transferee shall have no rights or interests in the Policy with respect to
that portion of the death proceeds designated in paragraph (2) of this
endorsement if the Insured ceases to be employed by the Company prior to the
Normal Retirement Date of 65 for any reason whatsoever (other than by reason of
a leave of absence which is approved by the Company), unless otherwise agreed to
by the Company and the Executive.

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               MODIFICATION OF ASSIGNMENT PROVISIONS OF THE POLICY

Upon the death of the Insured, the interest of any collateral assignee of the
Owner of the Policy designated in (3) above shall be limited to the portion of
the proceeds described in paragraph (1) above.

                                OWNERS AUTHORITY

The Insurer is hereby authorized to recognize the Owner's claim to rights
hereunder without investigating the reason for any action taken by the Owner,
including its statement of the amount of premiums it has paid on the Policy. The
signature of the Owner shall be sufficient for the exercise of any rights under
this Endorsement and the receipt of the Owner for any sums received by it shall
be a full discharge and release therefore to the Insurer.

Any transferee's rights shall be subject to this Endorsement.

The owner accepts and agrees to this split dollar endorsement.

Signed at St. Louis, Missouri, this 21st day of December, 1999.

COMPANY:

SOUTHSIDE BANCSHARES CORP.

By   /s/ Joseph W. Pope
Its Chief Financial Officer

The Trust accepts and agrees to the foregoing as direct beneficiary of the
portion of the proceeds described in paragraph (2) above.

Signed at St. Louis, Missouri, this 21st day of December, 1999.

TRUST:

THOMAS H. TESCHNER IRREVOCABLE
INSURANCE TRUST

By    /s/ John K. Pruellage
         Its Co-Trustee

By
         Its Co-Trustee

                                       8
<PAGE>   10
                                   SCHEDULE A

                         SPLIT DOLLAR AGREEMENT BETWEEN
                 SOUTHSIDE BANCSHARES CORP. AND THOMAS TESCHNER

<TABLE>
<CAPTION>
                 Age of                          TRUST INTEREST IN
              MR. TESCHNER                         Death Proceeds
<S>                                              <C>
        less than or equal to 65                     $3,474,940

                   66                                 3,349,917

                   67                                 3,214,517

                   68                                 3,067,879

                   69                                 2,909,070

                   70                                 2,737,080

                   71                                 2,550,815

                   72                                 2,349,090

                   73                                 2,130,622

                   74                                 1,894,021

                   75                                 1,637,783

                   76                                 1,360,277

                   77                                 1,059,738

                   78                                   734,254

                   79                                   381,756

      greater than or equal to 80                           -0-
            End of Schedule
</TABLE>

To calculate an amount for less than a full year of age of Executive, take the
number of completed months of service into the current Plan Year and divide by
12. Then multiply that fraction by the difference between (i) the balance for
the birthday prior to Executive's death and (ii) the balance for the next
birthday Executive would have attained had his death not occurred. Then subtract
that amount from the balance for the birthday prior to Executive's death. For
example, if the Executive's death occurs during the 70th year of age four months
after the Executive's birthday, then you would take 4/12 times the balance shown
for Age 70 minus the balance shown for Age 71. Then subtract that amount from
the balance shown for Age 70 to determine the amount due as death benefit
payment.

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00005-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00005-of-00352.parquet"}]]