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                                                                     EXHIBIT 4.1

                        PRINCETON NATIONAL BANCORP, INC.
                              AMENDED AND RESTATED
                          EMPLOYEE STOCK PURCHASE PLAN

     WHEREAS, Princeton National Bancorp, Inc., a Delaware corporation (the
"Company"), desires to establish the Princeton National Bancorp, Inc. Employee
Stock Purchase Plan (the "Plan") to provide a convenient and economical way for
certain employees of the Company or its subsidiaries to commence or increase
their ownership of the Company's common stock;

     NOW, THEREFORE, the Company hereby establishes the Plan, effective January
1, 1995, the terms of which shall be as follows:

     1.   DEFINITIONS. Wherever used herein, the following words and phrases
          shall have the meanings stated below unless a different meaning is
          plainly required by the content:

          (a)  "BOARD" means the Board of Directors of the Company.

          (b)  "COMMON STOCK" means shares of the common stock of the Company,
               $5.00 par value per share.

          (c)  "ELIGIBLE DIRECTOR" means each person who is not employed by the
               Company or a Subsidiary, who from time to time serves on the
               Board or on the board of directors of a Subsidiary, and who has
               been designated by the Board as eligible to purchase Common Stock
               under the Plan.

          (d)  "ELIGIBLE EMPLOYEE" means each person who is employed by the
               Company or a Subsidiary and who has been designated by the Board
               as eligible to purchase Common Stock under the Plan.

          (e)  "INVESTMENT DATE" means the last business day of each quarter
               (i.e., March 31, June 30, September 30 and December 31).

          (f)  "PARTICIPANT" means an Eligible Director or an Eligible Employee
               who has elected to participate in the Plan by completing an
               Authorization Card and making a lump-sum contribution or
               authorizing payroll deductions pursuant to Sections 5 and 6 of
               the Plan.

          (g)  "SUBSIDIARY" or "SUBSIDIARIES" means a corporation or
               corporations that, with the Company, is a member of a controlled
               group of corporations (as defined in Section 1563 of the Internal
               Revenue Code).

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     2. PURPOSE. The purpose of the Plan is to give Eligible Directors and
Eligible Employees of the Company and its Subsidiaries an opportunity to acquire
shares of Common Stock, and to promote the best interests of the Company and
enhance its long-term performance. Once an Eligible Director or Eligible
Employee is a Participant in the Plan, his lump-sum contributions and/or payroll
deductions will be used to purchase Common Stock under the terms of the Plan
during the period of time that such Eligible Director or Eligible Employee is a
Participant. Participants shall pay no brokerage commissions or service charges
for purchases made under the Plan. The Plan is not subject to the provisions of
the Employee Retirement Income Security Act of 1974.

     3. ADMINISTRATION. The Plan shall be administered by the Company, which, in
its discretion and by action of the Board, may delegate its powers with respect
to the administration of the Plan to any person or entity. Under the Plan, the
Company shall make purchases of Common Stock as agent for the Participants. If
an Eligible Director or an Eligible Employee elects to participate in the Plan,
the Company will keep a continuous record of his participation and send him a
semi-annual statement of his account under the Plan. The Company will also hold
and act as custodian of shares of Common Stock purchased under the Plan. This
will relieve Participants of the responsibility for the safekeeping of multiple
certificates for shares purchased and protect against loss, theft or destruction
of stock certificates. Normally, certificates for shares of Common Stock
purchased under the Plan will not be issued to Participants. The number of
shares of Common Stock credited to a Participant's account under the Plan will
be shown on his statement of account. However, certificates for any number of
whole shares of Common Stock credited to a Participant's account under the Plan
will be issued to him upon his written request to the Company, delivered to the
Company's address. In addition, at the Company's option, any time that the
number of shares in a Participant's account exceeds 50, a certificate for 50
shares may be issued to him. In either case, any remaining shares will continue
to be credited to the Participant's account. Certificates for fractional share
interests will not be issued.

     The Company reserves the right to interpret and regulate the Plan. The
Company may establish such procedures and make such other provisions for the
administration and operation of the Plan as it deems appropriate to give effect
to its purpose.

     4. ELIGIBILITY. As of November 30th of each calendar year, the Board will
designate each director and employee of the Company and its Subsidiaries who
will be an Eligible Director or Eligible Employee during the next calendar year;
provided, however, that no director shall vote with respect to his own
designation as an Eligible Director. An "Eligible Employee" must, as of such
November 30 date, be age 18 or older and have completed at least one year of
service in the employment of the Company or a Subsidiary. For this purpose, one
year of service shall mean 1,000 hours of employment.

     5. ELECTION TO PARTICIPATE. An Eligible Director or Eligible Employee may
become a Participant in the Plan during any calendar year in which he is an
Eligible Director or Eligible Employee by either of the two following methods:
(1) an Eligible Employee will become a

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Participant during the payroll period following receipt by the Company of a
completed Authorization Card approving payroll deductions or (2) an Eligible
Director will become a Participant following receipt by the Company of a
completed Authorization Card accompanying a lump-sum contribution; provided,
however, that lump-sum contributions received by the Company at least five
business days before an Investment Date will be invested on such Investment Date
in accordance with Section 6 below, and lump-sum contributions made within five
days before an Investment Date will be invested on the next following Investment
Date in accordance with Section 6. An Eligible Director or Eligible Employee may
join the Plan at any time during any calendar year in which he is an Eligible
Director or Eligible Employee.

     6. PAYROLL DEDUCTIONS AND LUMP-SUM CONTRIBUTIONS. In order to purchase
Common Stock under the Plan by payroll deductions, an Eligible Employee must
complete an Authorization Card indicating the amount the Company is to withhold
each pay period from the Eligible Employee's paychecks during the applicable
calendar year and directing the Company to use such amounts to purchase shares
of Common Stock. Deductions may be authorized in even multiples of $5 from a
minimum of $20 per month to a maximum of $20,000 in any calendar year.

     After an Authorization Card has been received by the Company and the
authority for the payroll deductions has been noted on the Company's payroll
records, the Company will withhold from a Participant's paychecks the amount
authorized by the Participant. The withholding will be made each pay period from
the paycheck for such period. The amounts withheld from all Participants'
paychecks during each month, and any lump-sum contributions made to the Plan
within the time specified in Section 5 above, will be pooled and used to buy
shares of Common Stock for the accounts of all Participants under the Plan on
the Investment Date immediately following the date on which such payments are
made, or deemed made, to the Plan.

     The amount of a Participant's payroll deductions can be revised, changed or
terminated by the Participant at any time by written notice to the Company and
completion of a new Authorization Card. Commencement, revision or termination of
payroll deductions will become effective as soon as practicable after a
Participant's new Authorization Card is received by the Company.

     An Eligible Director may purchase Common Stock under the Plan by making a
lump-sum payment to the Plan and completing an Authorization Card, not more
frequently than once each quarter during a calendar year that he is an Eligible
Director. In no event may the aggregate amount of lump-sum contributions made to
the Plan by an Eligible Director exceed $20,000 in any calendar year.

     Authorization Cards are effective until the earliest to occur of (1) the
date the Eligible Employee or Eligible Director elects to cease participation in
the Plan, (2) the date an individual ceases to be an Eligible Employee or an
Eligible Director, or (3) the date of the termination of the Plan. No interest
will be paid on payroll deductions or lump-sum contributions made to the Plan
pending investment on an Investment Date.

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     7. PURCHASE PRICE. The price of the shares bought with a Participant's
payroll deductions and/or lump-sum contributions will be the bid price for the
Common Stock, as reported in the Midwest Edition of the WALL STREET JOURNAL or
as reported by ABN AMRO Chicago Corporation in the event that the WALL STREET
JOURNAL does not list such price, in each case for the Investment Date on which
the shares are purchased (or, the next preceding day if no trading occurs in the
Common Stock on the Investment Date).

     8. NUMBER OF SHARES PURCHASED. On each Investment Date, accumulated payroll
deductions and lump-sum contributions from all Participants will be pooled and
used to purchase shares of Common Stock for the accounts of the Participants.
The maximum number of whole shares shall be purchased with such deductions and
contributions. The Company shall then contribute to the Plan an amount
sufficient to supplement the total of (1) any payroll deductions and lump-sum
contributions remaining after purchase of such maximum number of whole shares in
accordance with the preceding sentence, less (2) the value of any fractional
shares remaining in the suspense account described below from the prior
Investment Date, so that an additional whole share of Common Stock can be
purchased on such Investment Date. Each Participant's account shall be credited
with his pro rata share (computed to four decimal places) of the shares of
Common Stock purchased on such Investment Date. The number of shares credited to
each Participant's account will depend on the amount of the Participant's
payroll deductions and lump-sum contributions, as the case may be, and price of
the shares determined as provided under the heading "Purchase Price." Any
fractional shares remaining after the purchase of Common Stock for Plan to
Participants shall be held in a suspense account for the benefit of the Company
and used to offset the number of shares of Common Stock needed to fill purchases
for Participants on the next Investment Date.

     9. FEES AND EXPENSES. Participants will incur no brokerage commissions or
service charges for purchases made under the Plan. Certain charges as described
under the heading "Withdrawal" may be incurred upon a Participant's withdrawal
from the Plan or upon termination of the Plan.

     10. WITHDRAWAL. A Participant may withdraw from the Plan at any time. To
withdraw from the Plan, a Participant must notify the Company in writing of his
withdrawal. In the event a Participant withdraws, or in the event of the
termination of the Plan, within a reasonable time following the withdrawal
request or the termination of the Plan, certificates for whole shares credited
to the account of the withdrawing Participant, or all Participants in the case
of a termination of the Plan, will be delivered by the Company and a cash
payment will be made for the sale price (less brokerage commission and transfer
taxes, if any) of any fractional share interest and any additional payroll
deductions or lump-sum contributions credited to the account of the withdrawing
Participant, or all Participants in the case of a termination of the Plan. The
Company may establish such equitable arrangements for the sale of fractional
share interests as it shall deem appropriate. As an alternative to receiving
certificates for whole shares, a Participant may request the Company to sell all
of the shares held in his account under the Plan. The proceeds from the sale
(less any brokerage commissions and any transfer taxes) will be remitted to him
as soon as reasonably practical after his withdrawal request is received. Sale
requests may be accumulated and sales transactions, if

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necessary, will occur at least every twenty-five business days.

     If a request to withdraw is received by the Company at least five business
days prior to any Investment Date, the amount of the Participant's payroll
deductions and/or lump-sum contributions which would otherwise have been
invested on such Investment Date will be repaid to him as soon as practicable.
If a request to withdraw is received by the Company within five business days
prior to any Investment Date, the amount of the payroll deductions and lump-sum
contributions scheduled to be invested on such Investment Date will be so
invested. In either event, no subsequent payroll deductions will be made from
the paychecks of the Participant, and no lump sum contributions will be accepted
from the Participant, unless he completes a new Authorization Card providing for
such deductions or contributions.

     11. TERMINATION OF EMPLOYMENT OR SERVICE AS A DIRECTOR. A Participant's
participation in the Plan shall cease immediately upon his termination of
employment with the Company and its Subsidiaries for any reason, or his
termination of service on the Board or on the board of directors of a Subsidiary
for any reason. Within 60 days of a Participant's termination of employment or
service, certificates for whole shares credited to his account will be delivered
to him by the Company and a cash payment will be made to him for the sale price
(less brokerage commission and transfer taxes, if any) of any fractional share
interest and any additional payroll deduction or lump-sum contributions credited
to his account. In the event of the death of a Participant prior to receipt of
all payments and distributions to be made to him under the Plan, payments and
distributions shall be made to his beneficiary last designated by written
instrument delivered to the Company. If the Participant has not designated a
beneficiary or if the designated beneficiary is not living at such time, then
such payments and distributions shall be made to the Participant's spouse, or if
none, to his lawful descendants, per stirpes, or if none, to the legally
appointed representative of his estate.

     12. VOTING OF SHARES. Each Participant will have the authority to direct
the Company in the manner of voting the number of shares held in his account.
The shares of Common Stock in the suspense account created pursuant to Section 8
shall be voted by the Company in its sole discretion.

     13. CASH DIVIDENDS. Cash dividends paid on shares of Common Stock credited
to a Participant's account will be paid to the Participant as soon as
practicable following the dividend payment date. Dividend amounts payable to
Participants will be rounded to the nearest whole cent in the case of fractional
share interests.

     14. STOCK DIVIDENDS, STOCK SPLITS, OR RIGHTS OFFERING. Any shares
distributed by the Company as a stock dividend on shares of Common Stock
credited to a Participant's account under the Plan, or upon any split of such
shares, will be credited to his account. In a rights offering, the Company will
sell the rights to which a Participant is entitled by virtue of the shares of
Common Stock allocated to his account under the Plan and the proceeds will be
credited to his account and applied to the purchase of shares on the next
Investment Date.

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     15. AUTHORIZED SHARES. The Company has reserved 80,000 shares of Common
Stock for issuance under the Plan. Unless terminated earlier by the Company, the
Plan will terminate when all such shares have been purchased by Participants. In
the event of any change in the outstanding Common Stock of the Company as a
result of a merger, reorganization, stock split, reverse stock split, stock
dividend, recapitalization, combination or reclassification appropriate
proportionate adjustments will be made in the aggregate number of shares
reserved under the Plan.

     16. AMENDMENT AND TERMINATION. Although the Company intends to continue the
Plan as long as Common Stock reserved for issuance under it remains, the Company
reserves the right to suspend, modify or terminate the Plan at any time. Any
such suspension, modification or termination shall not affect a Participant's
right to shares of Common Stock already purchased for him (except that the
Company may take any action necessary to comply with applicable law). Upon the
termination of the Plan, the Company shall return to Participants any
accumulated payroll deductions and lump-sum contributions that have not been
used to purchase Common Stock as soon as practicable. Any Common Stock held in
the suspense account created pursuant to Section 8 shall be distributed to the
Company.

     17. STATEMENTS. Each Participant will receive a semi-annual statement of
his account, reflecting all activity in the account over such period.
Participants will also receive communications sent to other stockholders,
including the Annual Report of the Company, and its Notice of Annual Meeting and
Proxy Statement. Participants will receive information necessary for reporting
income, if any, realized by them under the Plan to the Internal Revenue Service.

     18. WITHHOLDING. All taxes subject to withholding payable with respect to
the amount of each Participant's payroll deductions under the Plan will be
deducted from the Participant's salary and will not reduce the amounts to be
paid to the Company.

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