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                                  Exhibit 31.1


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                    CERTIFICATION OF CHIEF EXECUTIVE OFFICER
            PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002


I, Richard A. Foss, certify that:

1.      I have reviewed this annual report on Form 10-K of Jacksonville Bancorp,
        Inc.;

2.      Based on my knowledge, this annual report does not contain any untrue
        statement of a material fact or omit to state a material fact necessary
        to make the statements made, in light of the circumstances under which
        such statements were made, not misleading with respect to the period
        covered by this quarterly report;

3.      Based on my knowledge, the financial statements, and other financial
        information included in this annual report, fairly present in all
        material respects the financial condition, results of operations and
        cash flows of the registrant as of, and for, the periods presented in
        this annual report;

4.      The registrant's other certifying officer(s) and I are responsible for
        establishing and maintaining disclosure controls and procedures (as
        defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
        registrant and have:

        a)      designed such disclosure controls and procedures or caused such
                disclosure controls and procedures to be designed under our
                supervision, to ensure that material information relating to the
                registrant, including its consolidated subsidiaries, is made
                known to us by others within those entities, particularly during
                the period in which this report is being prepared;

        b)      [intentionally omitted]

        c)      evaluated the effectiveness of the registrant's disclosure
                controls and procedures and presented in this report our
                conclusions about the effectiveness of the disclosure controls
                and procedures as of the period covered by this report based on
                such evaluation; and

        d)      disclosed in this report any change in the registrant's internal
                control over financial reporting that occurred during the
                registrant's most recent fiscal quarter (the registrant's fourth
                fiscal quarter in the case of an annul report) that has
                materially affected, or is reasonably likely to materially
                affect the registrant's internal control over financial
                reporting; and

5.      The registrant's other certifying officer(s) and I have disclosed, based
        on our most recent evaluation of internal control over financial
        reporting, to the registrant's auditors and the audit committee of
        registrant's board of directors (or persons performing the equivalent
        functions):

        a)      all significant deficiencies and material weaknesses in the
                design or operation of internal control over financial reporting
                which are reasonably likely to adversely affect the registrant's
                ability to record, process, summarize and report financial
                information; and

        b)      any fraud, whether or not material, that involves management or
                other employees who have a significant role in the registrant's
                internal controls over financial reporting.


March 23, 2006                            /s/ Richard A. Foss
--------------                            --------------------------------------
Date                                      Richard A. Foss
                                          President and Chief Executive Officer