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                                                                    EXHIBIT 99.1

                                 CERTIFICATIONS

I, William B. Kretzmer, certify that:

1. I have reviewed this quarterly report on Form 10-Q of MAI Systems
Corporation;

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 annual
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 officers and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-14 and 15d-14) for the registrant and we have:

    a)  designed such disclosure controls and procedures 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 annual report is being
        prepared;

    b)  evaluated the effectiveness of the registrant's disclosure controls and
        procedures as of a date within 90 days prior to the filing date of this
        annual report (the "Evaluation Date"); and

    c)  presented in this annual report our conclusions about the effectiveness
        of the disclosure controls and procedures based on our evaluation as of
        the Evaluation Date;

5. The registrant's other certifying officers and I have disclosed, based on our
most recent evaluation, to the registrant's auditors and the audit committee of
registrant's board of directors (or persons performing the equivalent function):

    a)  all significant deficiencies in the design or operation of internal
        controls which could adversely affect the registrant's ability to
        record, process, summarize and report financial data and have identified
        for the registrant's auditors any material weaknesses in internal
        controls; 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; and

6. The registrant's other certifying officers and I have indicated in this
annual report whether or not there were significant changes in internal controls
or in other factors that could significantly affect internal controls subsequent
to the date of our most recent evaluation, including any corrective actions with
regard to significant deficiencies and material weaknesses.

   Date: April 28, 2003                  By:  /s/ William B. Kretzmer
                                             ---------------------------------
                                              William B. Kretzmer
                                              Chief Executive Officer
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In connection with the Quarterly Report on Form 10-Q of MAI Systems Corporation
(the Company) for the period ended March 31, 2003 as filed with the Securities
and Exchange Commission on the date hereof (the Report), I, William B. Kretzmer,
Chief Executive Officer of the Company, certify pursuant to 18 U. S. C. Section
1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002,
that:

    1.  The Report fully complies with the requirements of Section 13 (a) or 15
        (d) of the Securities Exchange Act of 1934, as amended; and

    2.  The information contained in the Report fairly presents, in all material
        respects, the financial condition and results of operations of the
        Company.

   Date: April 28, 2003                  By:  /s/ William B. Kretzmer
                                             ---------------------------------
                                              William B. Kretzmer
                                              Chief Executive Officer