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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                              ---------------------

                                  SCHEDULE TO/A
                                 (Rule 14d-100)

            TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR 13(e)(1)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

                                (AMENDMENT NO. 3)

                             COMSHARE, INCORPORATED
                       (Name of Subject Company (Issuer))

                           CONDUCTOR ACQUISITION CORP.
                                    (Offeror)
                     an indirect wholly-owned subsidiary of
                        GEAC COMPUTER CORPORATION LIMITED
                               (Parent of Offeror)
                            (Names of Filing Persons)

                     COMMON STOCK, PAR VALUE $1.00 PER SHARE
                         (Title of Class of Securities)

                                    205912108
                      (CUSIP Number of Class of Securities)

                                CHARLES S. JONES
                      PRESIDENT AND CHIEF EXECUTIVE OFFICER
                        GEAC COMPUTER CORPORATION LIMITED
                         11 ALLSTATE PARKWAY, SUITE 300
                            MARKHAM, ONTARIO L3R 9T8
                                     CANADA
                                 (905) 475-0525
           (Name, address, and telephone numbers of person authorized
       to receive notices and communications on behalf of filing persons)

                                 with copies to:

                          ROBERT W. SWEET, JR., ESQUIRE
                                 FOLEY HOAG LLP
                              155 SEAPORT BOULEVARD
                           BOSTON, MASSACHUSETTS 02210


                            CALCULATION OF FILING FEE



    Transaction valuation*                                Amount of filing fee**
    ----------------------                                --------------------
                                                       
           $52,008,427                                            $4,208 ***




*Estimated for purposes of calculating the amount of the filing fee only. This
amount assumes the purchase at $4.60 per share in cash, pursuant to the Offer to
Purchase, of all 10,827,583 issued and outstanding shares of common stock, par
value $1.00 per share, of Comshare, Incorporated as of June 30, 2003 plus the
aggregate amount in cash to be paid to holders of outstanding options to
purchase shares of Comshare common stock determined by multiplying the excess,
if any, of $4.60 over the applicable exercise price of each such option by the
number of shares of Comshare common stock underlying such option.

**The amount of the filing fee, calculated in accordance with Rule 0-11 of the
Securities Exchange Act of 1934, as amended, equals $80.90 per $1,000,000 of the
transaction value.

***Previously paid in connection with the Offerors' Schedule TO filed with the
Securities and Exchange Commission on July 1, 2003.

[ ]   Check the box if any part of the fee is offset as provided by Rule
      0-11(a)(2) and identify the filing with which the offsetting fee was
      previously paid. Identify the previous filing by registration statement
      number, or the Form or Schedule and the date of its filing.

            Amount Previously Paid:

            Form or Registration No.:

            Filing Party:

            Date Filed:


[ ]   Check the box if the filing relates solely to preliminary communications
      made before the commencement of a tender offer.

[ ]   Check the appropriate boxes below to designate any transactions to which
      the statement relates:

[X]   third-party tender offer subject to Rule 14d-1.

[ ]   issuer tender offer subject to Rule 13e-4.

[ ]   going-private transaction subject to Rule 13e-3.

[ ]   amendment to Schedule 13D under Rule 13d-2


Check the following box if the filing is a final amendment reporting the results
of the tender offer:
[ ]

                                   SCHEDULE TO

      This Amendment No. 3 amends and supplements the Tender Offer Statement on
Schedule TO filed with the Securities and Exchange Commission on July 1, 2003,
as amended by Amendment No. 1 filed on July 17, 2003 and by Amendment No. 2
filed on July 18, 2003 (as amended, the "Schedule TO"), by Geac Computer
Corporation Limited, a corporation governed by the Canada Business Corporations
Act ("Geac") and Conductor Acquisition Corp., a Michigan corporation
("Purchaser") and an indirect wholly owned subsidiary of Geac. The Schedule TO
relates to the offer by Purchaser to purchase all of the outstanding shares of
common stock, par value $1.00 per share (the "Shares"), of Comshare,
Incorporated, a Michigan corporation (the "Company"), at a purchase price of
$4.60 per Share, net to the seller in cash, without interest thereon, upon the
terms and subject to the conditions set forth in the Offer to Purchase, dated
July 1, 2003, as amended, filed as Exhibit (a)(1)(A) to the Schedule TO (the
"Offer to Purchase"), and in the related Letter of Transmittal filed as Exhibit
(a)(1)(B) to the Schedule TO. The item numbers and responses thereto below are
in accordance with the requirements of Schedule TO. Unless otherwise defined
herein, all capitalized terms used herein shall have the respective meanings
given to such terms in the Offer to Purchase.

ITEM 11. ADDITIONAL INFORMATION

      Item 11 of the Schedule TO is hereby amended and supplemented to add the
following:

      "On July 31, 2003, Geac issued a press release, a copy of which is
attached hereto as Exhibit (a)(1)(I) and incorporated by reference herein,
announcing that Purchaser had extended the Offer, upon the terms and subject to
the conditions set forth in the Offer to Purchase, until 12:00 midnight, Eastern
time, on Friday, July 31, 2003, which will permit the acceptance by the
Purchaser of late tenders. A copy of the press release is attached hereto as
Exhibit (a)(1)(I) and is incorporated herein by reference. The Offer had been
previously scheduled to expire at 12:00 midnight, Eastern time, on Thursday,
July 31, 2003. EquiServe Trust Company, N.A., the depositary for the Offer (the
"Depositary"), has advised Geac and Purchaser that, as of the close of business
on July 30, 2003, an aggregate of approximately 8,832,531 Shares were tendered
to Purchaser pursuant to the Offer, including approximately 141,514 Shares
delivered through notices of guaranteed delivery, representing approximately
81.6% of the outstanding Shares.

      "Except for the extension of the expiration date, the Offer remains
subject to the terms and conditions set forth in the Offer to Purchase, as
amended, and other related materials filed by Geac and Purchaser with the
Commission."

ITEM  12. EXHIBITS.

      Item 12 of the Schedule TO is hereby amended and supplemented to add the
following:

      "(a)(1)(I) Press Release dated July 31, 2003."

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                                                     SIGNATURE

After due inquiry and to the best of my knowledge and belief, I certify that the
information set forth in this statement is true, complete and correct.

                                    GEAC COMPUTER CORPORATION LIMITED

                                    /s/ Craig C. Thorburn
                                    ____________________________________________

                                    By:  Craig C. Thorburn

                                    Its: Senior Vice President, Mergers &
                                          Acquisitions, Corporate Secretary

                                    CONDUCTOR ACQUISITION CORP.

                                    /s/ Craig C. Thorburn
                                    ____________________________________________

                                    By:  Craig C. Thorburn

                                    Its: Vice President

Date:  July 31, 2003



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                                INDEX TO EXHIBITS

EXHIBIT NUMBER             DESCRIPTION

(a) (1) (A)           Offer to Purchase, dated July 1, 2003.*

(a) (1) (B)           Letter of Transmittal.*

(a) (1) (C)           Notice of Guaranteed Delivery.*

(a) (1) (D)           Letter to Brokers, Dealers, Banks, Trust Companies and
                      other Nominees.*

(a) (1) (E)           Letter to Clients for use by Brokers, Dealers, Banks,
                      Trust Companies and other Nominees.*

(a) (1) (F)           Press Release dated July 1, 2003.*

(a) (1) (G)           Summary Advertisement, published in the New York Times on
                      July 3, 2003.*

(a) (1) (H)           Press Release dated July 16, 2003.**

(a) (1) (I)           Press Release dated July 31, 2003.

(b)                   Not Applicable.

(c)                   Not Applicable.

(d) (1)               Confidentiality Agreement dated April 24, 2003 between
                      Geac and the Company.*

(d) (2)               Confidentiality Agreement effective May 1, 2003 between
                      Geac and the Company.*

(d) (3)               Agreement and Plan of Merger, dated as of June 22, 2003,
                      by and among Geac, Purchaser and the Company.*

(d) (4)               Voting and Tender Agreement, dated as of June 22, 2003,
                      by and among Geac, Purchaser and Dennis G. Ganster.*

(d) (5)               Voting and Tender Agreement, dated as of June 22, 2003, by
                      and among Geac, Purchaser and each of Codec Systems
                      Limited and Anthony Stafford.*

(d) (6)               Employment agreement dated June 19, 2003 by and among the
                      Company, Geac Computers, Inc., Geac and Brian Hartlen.*

(d) (7)               Employment agreement dated June 19, 2003 by and among the
                      Company, Geac Computers, Inc., Geac and David King.*

(g)                   Not Applicable.

(h)                   Not Applicable.

*     Previously filed on July 1, 2003 with the Securities and Exchange
      Commission on Schedule TO by Purchaser and Geac.

**    Previously filed on July 17, 2003 with the Securities and Exchange
      Commission on Schedule TO by Purchaser and Geac.



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