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                                                                    Exhibit 10.4

                              DT INDUSTRIES, INC.
               THIRD AMENDMENT TO 1994 EMPLOYEE STOCK OPTION PLAN


     WHEREAS, DT Industries, Inc., a Delaware Corporation (the "Company"),
adopted the DT Industries, Inc. 1994 Employee Stock Option Plan (as amended, the
"Plan"); and

     WHEREAS, capitalized terms used herein and not otherwise defined have the
meanings given such terms in the Plan; and

     WHEREAS, Article IV of the Plan provides that the Board may at any time
amend or revise the terms of the Plan, subject to certain limitations described
therein; and

     WHEREAS, the Board has resolved to make certain amendments and revisions to
the Plan.

     NOW, THEREFORE, the Plan is hereby amended, effective as of June 20, 2002,
as follows:

     1. Section 2 of Article II is hereby amended to add subsection (e) at the
end of that section, as follows:

          e. Unless approved by a majority vote of the shares of Common Stock
     then outstanding, the Company shall not reduce the per share option price
     of any Non-Qualified Option or per share exercise price of any Incentive
     Option outstanding or to be granted in the future; cancel any outstanding
     Non-Qualified Options or Incentive Options held by a grantee with an
     agreement to re-grant Non-Qualified Options or Incentive Options to such
     optionee at a lower exercise price (including entering into any "6 month
     and 1 day" cancellation and re-grant scheme), whether or not the cancelled
     options are put back into the available pool for grant; replace underwater
     options with restricted stock in an exchange, buy-back or other similar
     scheme; or replace any options with new options having a lower exercise
     price or accelerated vesting schedule in an exchange, buy-back or other
     similar scheme.

     2. Section 1(a) of Article IV of the Plan, as amended, is hereby amended
and restated to read in its entirety as follows:

          a. The Board may, in its discretion, at any time suspend or terminate
     the Plan. The Board may also at any time amend or revise the terms of the
     Plan or any Option granted under the Plan, provided that no such amendment
     or revision shall without shareholder approval:

               (i) increase the number of shares reserved for issuance pursuant
          to the Options granted under the Plan (except as permitted under the
          provisions of Article III hereof);


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               (ii) change the purchase price established pursuant to Section 2
          of Article II hereof (except as permitted under the provisions of
          Article III hereof);

               (iii) permit the granting of Options to anyone other than as
          provided in Article II hereof; or

               (iv) modify the provisions of Sections 2(a) or 2(e) of Article
          II.

     3. No other provision of the Plan shall be altered, amended, revised or
otherwise modified hereby.

         IN WITNESS WHEREOF, this Amendment has been duly executed by order of
the Board as of the 20th day of June, 2002.


                                     DT INDUSTRIES, INC.

                                     By:   /s/ Dennis S. Dockins
                                        ------------------------
                                        Dennis S. Dockins
                                        General Counsel and Secretary