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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. 6)

                             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: third-party tender offer subject to Rule 14d-1.

[X]  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:
[X]
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                                   SCHEDULE TO

     This Amendment No. 6 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, Amendment No. 2 filed on
July 18, 2003, Amendment No. 3 filed on July 31, 2003, Amendment No. 4 filed on
August 1, 2003 and Amendment No. 5 filed on August 12, 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.

ITEMS 1 THROUGH 9, AND ITEM 11.

     On August 13, 2003, Geac, Purchaser and the Company executed the First
Amendment to Agreement and Plan of Merger (the "First Amendment"). The First
Amendment, a copy of which is attached hereto as Exhibit (d)(8) and incorporated
by reference herein, is intended to facilitate Purchaser's exercise of the
Top-Up Option by making certain technical amendments to the terms of the Top-Up
Option to permit Purchaser to exercise the Top-Up Option in whole or in part, on
more than one occasion from time to time.

     The subsequent offering period of the Offer expired at 5:00 p.m., Eastern
time, on Wednesday, August 13, 2003. The Depositary for the Offer has advised
Geac and Purchaser that, as of the expiration of the subsequent offering period
of the Offer, and including Shares tendered and accepted during the initial
offering period which expired on July 31, 2003, an aggregate of approximately
9,792,548 Shares were validly tendered to Purchaser in the Offer. Purchaser has
accepted all validly tendered Shares for payment in accordance with the terms of
the Offer.

     Also on August 13, 2003, Purchaser purchased directly from the Company an
additional 363,201 shares of common stock of the Company at a price of $4.60 per
share, for an aggregate price of $1,670,725, in connection with the exercise of
the Top-Up Option granted in the Merger Agreement, as amended. The shares
purchased pursuant to the Top-Up Option, together with the shares tendered and
accepted pursuant to the Offer, represent a total of 10,155,749 Shares, or
90.61%, of the 11,208,347 Shares outstanding as of August 13, 2003.

     Pursuant to the terms of the Merger Agreement, Geac will cause the merger
of Purchaser with and into the Company as soon as practicable. As a result of
the Merger, each issued and outstanding Share that was not tendered in the Offer
(other than Shares that are owned by Geac


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or the Company or any of their respective wholly owned subsidiaries, all of
which will be cancelled without any consideration being exchanged therefor) will
be, by virtue of the Merger and without any action on the part of the holder
thereof, converted into the right to receive $4.60 in cash, without interest
thereon and less any required withholding taxes, upon surrender of the
certificate representing such Share, and the Company will become an indirect
wholly owned subsidiary of Geac.

     On August 14, 2003, Geac issued a press release, a copy of which is
attached hereto as Exhibit (a)(1)(M) and incorporated by reference herein,
announcing the expiration of the subsequent offering period of the Offer and
Purchaser's exercise of the Top-Up Option pursuant to the terms of the Merger
Agreement, as amended.


ITEM 12. EXHIBITS.

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

     "(a)(1)(M) Press Release dated August 14, 2003."

     "(d)(8)    First Amendment to Agreement and Plan of Merger, by and among
                Geac, Purchaser and the Company, dated as of August 13, 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, and Corporate Secretary


                                           CONDUCTOR ACQUISITION CORP.


                                           /s/ Craig C. Thorburn
                                           -------------------------------------
                                           By: Craig C. Thorburn
                                           Its: Vice President


Date:  August 14, 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.***

  (a)(1)(J)        Press Release dated August 1, 2003.****

  (a)(1)(K)        Press Release dated August 1, 2003.****

  (a)(1)(L)        Press Release dated August 12, 2003.*****

  (a)(1)(M)        Press Release dated August 14, 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.*



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  (d)(8)           First Amendment to Agreement and Plan of Merger, by and
                   among Geac, Purchaser and the Company, dated as of August
                   13, 2003.

  (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.

***   Previously filed on July 31, 2003 with the Securities and Exchange
      Commission on Schedule TO by Purchaser and Geac.

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

***** Previously filed on August 12, 2003 with the Securities and Exchange
      Commission on Schedule TO by Purchaser and Geac.





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