Exhibit 99.4

                               CERTIFICATE OF AMENDMENT
                                          TO
                              ARTICLES OF INCORPORATION
                                          OF
                                     ZAPPCO, INC.


    The undersigned, being the Chief Executive Officer and Secretary of 
Zappco, Inc., a Minnesota corporation, do hereby certify that the following 
amendment to Article VII of the Articles of Incorporation was adopted by vote 
of the Shareholders and Directors of the corporation on September 4, 1987 and 
shall read as follows:

                                     ARTICLE VII

         The aggregate number of shares which this Corporation shall have
    authority to issue is 35,000 shares, of which 25,000 shares shall be known
    as "Common Stock", and 10,000 shares shall be known as "Perpetual Preferred
    Stock".

         The 25,000 shares of Common Stock shall be voting stock and have a par
    value of $1.00 per share, and an aggregate par value of $25,000.00.  The
    10,000 shares of Perpetual Preferred Stock shall be non-voting and have a
    par value of $100.00 per share, and an aggregate par value of
    $1,000,000.00.

         A.   The holders of the Perpetual Preferred Stock shall be entitled to
              receive out of earnings or surplus legally available therefor,
              semi-annual dividends payable in cash at such times and rates as
              shall be determined by the Board of Directors.  Such dividends
              shall be paid before any dividends shall be set apart or paid on
              the Common Stock.  Should the surplus or net profits arising from
              the business of the corporation prior to any dividend day be
              insufficient to pay dividends on the Perpetual Preferred Stock,
              such dividends shall be payable from future profits, and no
              dividends shall, at any time, be paid on the Common Stock, until
              the full amount owing on all the Perpetual Preferred Stock shall
              have been paid or set apart.

         B.   In the event of liquidation or dissolution or winding up (whether
              voluntary or involuntary) of the Corporation, the holders of the
              Perpetual Preferred Stock shall be entitled to be paid One
              Hundred and no/100 ($100.00) Dollars per share and the unpaid
              dividends accrued thereon before any amount shall be paid to the
              holders of the Common Stock; and, after the payment thereof the
              remaining assets and funds shall be divided



              and paid to holders of the Common Stock pro rata according to
              their respective shares.

         C.   The Corporation shall have the right from time to time to
              purchase, redeem, retire and cancel any or all of the outstanding
              Perpetual Preferred Stock of the Corporation, on any date upon 30
              days' or more written notice to the holder or holders of the
              Perpetual Preferred Stock, in such manner and amounts as the
              Board of Directors may determine, by paying to the respective
              holders of the stocks so retired a sum equal to One Hundred and
              no/100 ($100.00) Dollars per share of the stock so retired and
              canceled, together with all unpaid accumulated dividends thereon,
              if any.

         D.   The holders of the Common Stock shall be entitled to receive,
              when and as declared by the Board of Directors, out of earnings
              or surplus legally advisable therefor, dividends, payable either
              in cash, in property or in shares of the Capital Stock of the
              Corporation, provided that all dividends due and owing the
              holders of the Perpetual Preferred shares of stock have been
              paid.

         E.   All shares of stock may be allotted as and when the Board of
              Directors shall determine and, under and pursuant to the laws of
              the State of Minnesota, the Board of Directors shall have the
              power to fix or alter, from time to time, in respect to each
              class of shares then unalloted, any and all of the following:
              the dividend rate; the redemption price; the liquidation price;
              the conversion rights and the sinking or purchase fund rights of
              shares of any class, or any series of any class, or the number of
              shares constituting the series of any class.

         F.   The Board of Directors shall have the power to fix the terms,
              provisions and conditions of options to purchase or subscribe
              for, or rights to convert any of its securities into, shares of
              any class or classes, including the price and conversion basis
              thereof, and authorize the issuance thereof.

         G.   The Board of Directors shall have the power to issue, upon
              authorization of the shareholders, any such other equity
              instruments, which may or may not be convertible to shares of any
              class of stock of the Corporation, for the purpose of increasing
              the Corporation's total capital.


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         H.   No holder of any class of stock of the Corporation shall be
              entitled to any cumulative voting rights.

         I.   No holder of stock of the Corporation shall have any
              preferential, pre-emptive or other right of subscription to any
              shares or any class of stock of the Corporation allotted or sold
              or to be allotted or sold and now or hereafter authorized, or to
              any obligations convertible into stock of the Corporation of any
              class, nor any right of subscription to any part thereof.

    IN WITNESS WHEREOF, the undersigned have hereunto set their hands this 4th
day of September, 1987.



                                    /s/Edward Zapp
                                  -----------------------------------
                                  President and Chief Executive Officer


                                   /s/Gerald Plachecki
                                  -----------------------------------
                                  Secretary


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