<PAGE>

                                                                     EXHIBIT 4.1

                              AMENDED AND RESTATED
Form BCA-10.30               ARTICLES OF AMENDMENT
(Rev. Jan. 1999)                                       File #
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Jesse White
Secretary of State
Department of Business Services                        This space for use by
Springfield, IL 62756                                   Secretary of State
Telephone (217) 782-1832
-------------------------------
Remit payment in check or money                        Date
order, payable to "Secretary of
State."                                                Franchise Tax  $
                                                       Filing Fee*    $25.00
The filing fee for restated                            Penalty        $
articles of amendment - $100.00
                                                       Approved:
http://www.sos.state.il.us
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1.   CORPORATE NAME: Main Street Trust, Inc.
                    ------------------------------------------------------------
                                                                 (Note 1)

2.   MANNER OF ADOPTION OF AMENDMENT:

          The following amendment of the Articles of Incorporation was adopted
          on        March 21       ,    2000      in the manner indicated below.
             ----------------------  ------------
                (Month & Day)           (Year)
          ("X" one box only)

     / /  By a majority of the incorporators, provided no directors were named
          in the articles of incorporation and no directors have been elected;
                                                                 (Note 2)

     / /  By a majority of the board of directors, in accordance with Section
          10.10, the corporation having issued no shares as of the time of
          adoption of this amendment;
                                                                 (Note 2)

     / /  By a majority of the board of directors, in accordance with Section
          10.15, shares having been issued but shareholder action not being
          required for the adoption of the amendment;
                                                                 (Note 3)

     / /  By the shareholders, in accordance with Section 10.20, a resolution of
          the board of directors having been duly adopted and submitted to the
          shareholders. At a meeting shareholders, not less than the minimum
          number of votes required by statute and by the articles of
          incorporation were voted in favor of the amendment;
                                                                 (Note 4)

     / /  By the shareholders, in accordance with Sections 10.20 and 7.10, a
          resolution of the board of directors having been duly adopted and
          submitted to the shareholders. A consent in writing has been signed
          by shareholders having not less than the minimum number of votes
          required by statute and by the articles of incorporation. Shareholders
          who have not consented in writing have been given notice in accordance
          with Section 7.10;
                                                                 (Notes 4 & 5)

     /X/  By the shareholders, in accordance with Sections 10.20 and 7.10, a
          resolution of the board of directors having been duly adopted and
          submitted to the shareholders. A consent in writing has been signed
          by all the shareholders entitled to vote on this amendment;

                                                                 (Note 5)

3.   TEXT OF AMENDMENT:

     a.   When amendment effects a name change, insert the new corporate name
          below. Use Page 2 for all other amendments.

          Article I: The name of the corporation is:


--------------------------------------------------------------------------------
                                   (NEW NAME)


                 All changes other than name, include on page 2
                                     (over)

<PAGE>

                                TEXT OF AMENDMENT

     b.   (IF AMENDMENT AFFECTS THE CORPORATE PURPOSE, THE AMENDED PURPOSE IS
          REQUIRED TO BE SET FORTH IN ITS ENTIRETY. IF THERE IS NOT SUFFICIENT
          SPACE TO DO SO, ADD ONE OR MORE SHEETS OF THIS SIZE.)

                                 See Exhibit A







                                     Page 2
<PAGE>


4.  The manner, if not set forth in Article 3b, in which any exchange,
    reclassification or cancellation of issued shares, or a reduction of the
    number of authorized shares of any class below the number of issued
    shares of that class, provided for or effected by this amendment, is as
    follows: (IF NOT APPLICABLE, INSERT "NO CHANGE")

    No Change

5.  (a) The manner, if not set forth in Article 3b, in which said amendment
    effects a change in the amount of paid-in capital (Paid-in capital
    replaces the terms Stated Capital and Paid-in Surplus and is equal to the
    total of these accounts) is as follows: (IF NOT APPLICABLE, INSERT "NO
    CHANGE")

    No Change

    (b) The amount of paid-in capital (Paid-in Capital replaces the terms
    Stated Capital and Paid-in Surplus and is equal to the  total of these
    accounts) as changed by this amendment is as follows: (IF NOT APPLICABLE,
    INSERT "NO CHANGE")

    No Change

                                   Before Amendment       After Amendment

                Paid-in Capital    $_______________       $______________


   (Complete either Item 6 or 7 below. All signatures must be in BLACK INK.)

6.  The undersigned corporation has caused this statement to be signed by its
    duly authorized officers, each of whom affirms, under penalties of
    perjury, that the facts stated herein are true.

<TABLE>

<S>                                                 <C>
Date         March 21,                    2000      Main Street Trust, Inc.
     ----------------------------------, ------     ------------------------------------------------
         (MONTH & DAY)                   (YEAR)     (EXACT NAME OF CORPORATION AT DATE OF EXECUTION)

attested by /s/ Teresa M. Marsh                     by /s/ Van A. Dukeman
            ----------------------                     ---------------------------------------------
(SIGNATURE OF SECRETARY OR ASSISTANT SECRETARY)         (SIGNATURE OF PRESIDENT OR VICE PRESIDENT)
            -----------------------------------     ------------------------------------------------
            Teresa M. Marsh, Secretary              Van A. Dukeman, President
            -----------------------------------     ------------------------------------------------
               (TYPE OR PRINT NAME AND TITLE)               (TYPE OR PRINT NAME AND TITLE)
</TABLE>

7.  If amendment is authorized pursuant to Section 10.10 by the incorporators,
    the incorporators must sign below, and type or print name and title.

                                       OR

    If amendment is authorized by the directors pursuant to Section 10.10 and
    there are no officers, then a majority of the directors or such directors
    as may be designated by the board, must sign below, and type or print name
    and title.

    The undersigned affirms, under the penalties of perjury, that the facts
    stated herein are true.

<TABLE>

<S>                                                 <C>
Dated ____________________________, _________
            (MONTH & DAY)            (YEAR)
_____________________________________________     _______________________________________

_____________________________________________     _______________________________________

_____________________________________________     _______________________________________

_____________________________________________     _______________________________________

</TABLE>

                                   Page 3

<PAGE>


                            NOTES and INSTRUCTIONS

NOTE 1:   State the true exact corporate name as it appears on the records of
          the office of the Secretary of State, BEFORE any amendments herein
          reported.

NOTE 2:   Incorporators are permitted to adopt amendments ONLY before any
          shares have been issued and before any directors have been named
          or elected.                                       (Section 10.10)

NOTE 3:   Directors may adopt amendments without shareholder approval in only
          seven instances, as follows:
          (a)  to remove the names and addresses of directors named in the
               articles of incorporation;
          (b)  to remove the name and address of the initial registered agent
               and registered office, provided a statement pursuant to
               Section 5.10 is also filed;
          (c)  to increase, decrease, create or eliminate the par value of
               the shares of any class, so long as no class or series of shares
               is adversely affected.
          (d)  to split the issued whole shares and unissued authorized
               shares by multiplying them by a whole number, so long as no
               class or series is adversely affected thereby;
          (e)  to change the corporate name by substituting the word
               "corporation", "incorporated", "company", "limited", or the
               abbreviation "corp.", "inc.", "co.", or "ltd." for a similar
               word or abbreviation in the name, or by adding a geographical
               attribution to the name;
          (f)  to reduce the authorized shares of any class pursuant to a
               cancellation statement filed in accordance with Section 9.05.
          (g)  to restate the articles of incorporation as currently amended.
                                                               (Section 10.15)
NOTE 4:   All amendments not adopted under Section 10.10 or Section 10.15
          require (1) that the board of directors adopt a resolution setting
          forth the proposed amendment and (2) that the shareholders approve
          the amendment.

          Shareholder approval may be (1) by vote at a shareholders' meeting
          (EITHER ANNUAL OR SPECIAL) or (2) by consent in writing, without a
          meeting.

          To be adopted, the amendment must receive the affirmative vote or
          consent of the holders of at least 2/3 of the outstanding shares
          entitled to vote on the amendment (BUT IF CLASS VOTING APPLIES,
          THEN ALSO AT LEAST A 2/3 VOTE WITHIN EACH CLASS IS REQUIRED).

          The articles of incorporation may supersede the 2/3 vote
          requirement by specifying any smaller or larger vote requirement not
          less than a majority of the outstanding shares entitled to vote and
          not less than a majority within each class when class voting
          applies.                                              (Section 10.20)

NOTE 5:   When shareholder approval is by consent, all shareholders must be
          given notice of the proposed amendment at least 5 days before the
          consent is signed. If the amendment is adopted, shareholders who
          have not signed the consent must be promptly notified of the
          passage of the amendment.                   (Sections 7.10 & 10.20)



                                     Page 4


<PAGE>

                                    EXHIBIT A

                          ATTACHMENT TO THE ARTICLES OF
                          AMENDMENT AND RESTATEMENT OF
                          ARTICLES OF INCORPORATION OF
                             MAIN STREET TRUST, INC.
                        ORIGINALLY FILED AUGUST 12, 1999


                              ARTICLE 1 - RESTATED
                                      NAME

             The name of the Corporation is Main Street Trust, Inc.

                              ARTICLE 2 - RESTATED
                           REGISTERED OFFICE AND AGENT

     The name and address of the Corporation's registered agent and office is:

               Registered Agent                    Registered Office
               ----------------                    -----------------
               Dennis R. Wendte                    333 West Wacker Drive
                                                   Suite 2700
                                                   Chicago, Illinois 60606

                              ARTICLE 3 - RESTATED
                                     PURPOSE

     The transaction of any or all lawful purposes for which corporations may be
incorporated under the Illinois Business Corporation Act of 1983, as amended.

                        ARTICLE 4 - AMENDED AND RESTATED
                                AUTHORIZED STOCK

     PARAGRAPH 1. The total number of shares of all classes of capital stock
which the Corporation has the authority to issue is 17,000,000 shares, which are
divided into two classes as follows:

          (a)  2,000,000 shares of Preferred Stock without par value (the
"Preferred Stock"); and


<PAGE>

          (b)  15,000,000 shares of Common Stock with a par value of $0.01 per
share (the "Common Stock").

     PARAGRAPH 2. The preferences, qualifications, limitations, restrictions and
special or relative rights in respect of the shares of each class are:

          SECTION 1. PREFERRED STOCK. The board of directors is authorized, at
any time and from time to time, to provide for the issuance of shares of
Preferred Stock in one or more series with such designations, preferences,
voting powers and relative, participating, optional or other special rights and
qualifications, limitations or restrictions thereof as are stated and expressed
in the resolution or resolutions providing for the issuance of such Preferred
Stock adopted by the board of directors, and as are not stated and expressed in
these articles of incorporation or any amendment thereto, including, but not
limited to, determination of any of the following:

          (a)  the distinctive serial designation and the number of shares
     constituting a series;

          (b)  the dividend rate or rates, whether dividends are cumulative (and
     if so on what terms and conditions), the payment date or dates for
     dividends and the participating or other special rights, if any, with
     respect to dividends;

          (c)  the voting rights, full or limited, if any, of the shares of the
     series, which could include the right to elect a specified number of
     directors in any case if dividends on the series are not paid for in a
     specified period of time;

          (d)  whether the shares of the series are redeemable and, if so, the
     price or prices at which, and the terms and conditions on which, the shares
     may be redeemed, which prices, terms and conditions may vary under
     different conditions and at different redemption dates;

          (e)  the amount or amounts, if any, payable upon the shares of the
     series in the event of voluntary or involuntary liquidation, dissolution or
     winding up of the Corporation prior to any payment or distribution of the
     assets of the Corporation to any class or classes of stock of the
     Corporation ranking junior to the series;

          (f)  whether the shares of the series are entitled to the benefit of a
     sinking or retirement fund to be applied to the purchase or redemption of
     shares of the series and the amount of the fund and the manner of its
     application, including the price or prices at which the shares of the
     series may be redeemed or purchased through the application of the fund;

          (g)  whether the shares are convertible into, or exchangeable for,
     shares of any other class or classes or of any other series of the same or
     any other class or classes of stock of the Corporation and the conversion
     price or prices, or the rates of exchange, and


                                       2

<PAGE>

     the adjustments thereof, if any, at which the conversion or exchange may be
     made, and any other terms and conditions of the conversion or exchange; and

          (h)  any other preferences, privileges and powers, and relative,
     participating, optional or other special rights, and qualifications,
     limitations or restrictions of a series, as the board of directors may deem
     advisable and as are not inconsistent with the provisions of these articles
     of incorporation.

          SECTION 2. COMMON STOCK.

               A.   DIVIDENDS. Subject to the preferential rights of the
Preferred Stock, the holders of the Common Stock are entitled to receive, to the
extent permitted by law, such dividends as may be declared from time to time by
the board of directors.

               B.   LIQUIDATION. In the event of the voluntary or involuntary
liquidation, dissolution, distribution of assets or winding up of the
Corporation, after distribution in full of the preferential amounts, if any, to
be distributed to the holders of shares of Preferred Stock, holders of Common
Stock shall be entitled to receive all of the remaining assets of the
Corporation of whatever kind available for distribution to stockholders ratably
in proportion to the number of shares of Common Stock held by them respectively.
The board of directors may distribute in kind to the holders of Common Stock
such remaining assets of the Corporation or may sell, transfer or otherwise
dispose of all or any part of such remaining assets to any other corporation,
trust or other entity and receive payment therefor in cash, stock or obligations
of such other corporation, trust or other entity, or any combination hereof, and
may sell all or any part of the consideration so received and distribute any
balance thereof in kind to holders of Common Stock. Neither the merger or
consolidation of the Corporation into or with any other corporation or
corporations, nor the purchase or redemption of shares of stock of the
Corporation of any class, nor the sale or transfer by the Corporation of all or
any part of its assets, nor the reorganization or recapitalization of the
Corporation, shall be deemed to be a dissolution, liquidation or winding up of
the Corporation for the purposes of this paragraph.

               C.   VOTING RIGHTS. Except as may be otherwise required by law or
in these articles of incorporation or any amendment thereto, each holder of
Common Stock has one vote in respect of each share of stock held by the holder
of record on the books of the Corporation on all matters voted upon by the
stockholders. No shareholder shall have cumulative voting rights for the
election of directors.

     PARAGRAPH 3. OTHER PROVISIONS.

          SECTION 1. NO PREEMPTIVE RIGHTS. No stockholder shall have any
preemptive right to subscribe to an additional issue of stock, whether now or
hereafter authorized, of any class or series or to any securities of the
Corporation convertible into such stock.

          SECTION 2. UNCLAIMED DIVIDENDS. Any and all right, title, interest and
claim in or to any dividends declared by the Corporation, whether in cash,
stock, or otherwise, which are unclaimed by the stockholder entitled thereto for
a period of five years after the close of


                                       3
<PAGE>

business on the payment date, shall be and be deemed to be extinguished and
abandoned; and such unclaimed dividends in the possession of the Corporation,
its transfer agents or other agents or depositaries shall at such time become
the absolute property of the Corporation, free and clear of any and all claims
of any persons whatsoever.

                              ARTICLE 5 - RESTATED
                          ISSUED AND OUTSTANDING SHARES

     The number of shares of each class issued and outstanding on the date of
filing these Articles of Amendment and Restatement of the Articles of
Incorporation of the Corporation are:

<TABLE>
<CAPTION>
               Par Value per   Number of Shares   Number of Shares
    Class          Share          Authorized         Issued           Paid-in Capital
    -----      -------------   ----------------   ----------------    ---------------
<S>            <C>             <C>                <C>                 <C>
Common             $0.01            1,000              1,000               $100.00
Preferred          No par               0                  0                  0.00
                                                              Total        $100.00
</TABLE>

                              ARTICLE 6 - RESTATED
                                     BYLAWS

     The bylaws may be amended, altered or repealed by the board of directors in
the manner provided in the bylaws.

                              ARTICLE 7 - RESTATED
                                 WRITTEN BALLOTS

     Election of directors need not be by written ballot unless the bylaws of
the Corporation so provide.

                              ARTICLE 8 - RESTATED
                                   AMENDMENTS

     The Corporation reserves the right to amend, alter, change or repeal any
provision contained in these articles of incorporation, in the manner now or
hereafter prescribed by statute, and all rights conferred upon shareholders
herein are granted subject to this reservation.

                              ARTICLE 9 - RESTATED
                                 INDEMNIFICATION

     Each person who is or was a director or officer of the Corporation and each
person who serves or served at the request of the Corporation as a director,
officer or partner of another

                                       4
<PAGE>

enterprise shall be indemnified by the Corporation in accordance with, and to
the fullest extent authorized by, the Illinois Business Corporation Act of 1983,
as the same now exists or may be hereafter amended. No amendment to or repeal of
this Article shall apply to or have any effect on the rights of any individual
referred to in this Article for or with respect to acts or omissions of such
individual occurring prior to such amendment or repeal.

                              ARTICLE 10 - RESTATED
                         PERSONAL LIABILITY OF DIRECTORS

     To the fullest extent permitted by the Illinois Business Corporation Act of
1983, as the same exists or may hereafter be amended, a director of the
Corporation shall not be personally liable to the Corporation or its
shareholders for monetary damages for breach of fiduciary duty of a director.

                        ARTICLE 11 - AMENDED AND RESTATED
                               BOARD OF DIRECTORS

     The number of directors constituting the entire board of directors shall
not be less than twelve (12) nor more than seventeen (17) as fixed from time to
time by resolution of a majority of the number of directors which immediately
prior to such proposed change had been fixed, in the manner prescribed herein,
by the board of directors of the Corporation, PROVIDED, HOWEVER, that the number
of directors shall not be reduced as to shorten the term of any director at the
time in office, and provided further, that the number of directors constituting
the entire board of directors shall be two (2) until otherwise fixed as
described immediately above.

     The directors of the Corporation shall be divided into three classes, Class
I, Class II and Class III, as nearly equal in number as the then total number of
directors constituting the entire board of directors permits with the term of
office of one class expiring each year. Directors of Class I shall hold office
for an initial term expiring at the 2000 annual meeting, directors of Class II
shall hold office for an initial term expiring at the 2001 annual meeting and
directors of Class III shall hold office for an initial term expiring at the
2002 annual meeting. At each annual meeting of shareholders, the successors to
the class of directors whose term shall then expire shall be elected to hold
office for a term expiring at the third succeeding annual meeting. Any vacancies
in the board of directors for any reason, and any directorships resulting from
any increase in the number of directors, may be filled by the board of
directors, acting by a majority of the directors then in office, although less
than a quorum, and any directors so chosen shall hold office until the next
election of the class for which such directors shall have been chosen and until
their successors shall be elected and qualified. If the number of directors is
changed, any increase or decrease in the number of directors shall be
apportioned among the classes so as to maintain all classes as equal in number
as possible. There shall be no cumulative voting in the election of directors.

     Notwithstanding any other provisions of these articles of incorporation or
the bylaws of the Corporation (and notwithstanding the fact that some lesser
percentage may be specified by law, these articles of incorporation or the
bylaws of the Corporation), any director or the entire


                                       5
<PAGE>

board of directors of the Corporation may be removed at any time, but only for
cause and by shareholder action at an annual meeting of shareholders or at a
meeting of the shareholders called for that purpose. Cause for removal shall be
deemed to exist only if the director whose removal is proposed has been
convicted of a felony by a court of competent jurisdiction or has been adjudged
by a court of competent jurisdiction to be liable for gross negligence or
willful misconduct in the performance of such director's duty to the Corporation
and such adjudication is no longer subject to direct appeal.

                       ARTICLE 12 - AMENDED AND RETSTATED
                         ADDITIONAL VOTING REQUIREMENTS

          PARAGRAPH 1. VOTING REQUIREMENTS. Notwithstanding any other provision
of these articles of incorporation:

               (a)  any merger or consolidation of the Corporation into any
other corporation;

               (b)  any sale, lease, exchange or other disposition by the
Corporation of assets constituting all or substantially all of the assets of the
Corporation and its Subsidiaries taken as a whole to or with any other
corporation, person or other entity in a single transaction or a series of
related transactions;

               (c)  the voluntary dissolution of the Corporation; and

               (d)  the amendment, alteration, change or repeal of these
articles of incorporation;

shall require the affirmative vote of the holders of shares having at least a
majority of the voting power of all outstanding stock of the Corporation
entitled to vote thereon. Such affirmative vote shall be required
notwithstanding the fact that a greater vote may be specified by law in the
absence of this provision, or otherwise in these articles of incorporation or by
the bylaws of the Corporation.

          PARAGRAPH 2. DEFINITIONS. For purposes of this Article, the term
"Subsidiary" means any entity in which the Corporation beneficially owns,
directly or indirectly, more than 80% of the outstanding voting stock. The
phrase "voting security" as used in paragraph A of this Article shall mean any
security which is (or upon the happening of any event, would be) entitled to
vote for the election of directors, and any security convertible, with or
without consideration into such security or carrying any warrant or right to
subscribe to or purchase such a security.


                                       6