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                                                                  EXHIBIT 10.39

                      AMENDMENT TO STOCK PURCHASE AGREEMENT



         This Amendment to the Stock Purchase Agreement (this "Amendment") is
made and entered into effective as of April 2, 1996, by and between Software
Publishing Corporation (the "Buyer") and Daniel J. Fraisl, Carl Meyer and
Anthony N. Hoeber (collectively referred to as the "Shareholders"), with
reference to the following facts:

         A. WHEREAS, the parties have previously entered into that certain Stock
Purchase Agreement, effective as of March 31, 1995 (the "Stock Purchase
Agreement"), pursuant to which Buyer acquired all of the outstanding capital
stock of Digital Paper, Inc. from the Shareholders.

         B. WHEREAS, pursuant to Sections 2.3 (a) and 2.3 (b) of the Stock
Purchase Agreement, the Shareholders were to receive certain conditional
payments upon the occurrence of certain events, such that an aggregate of
$1,500,000 would be paid to the Shareholders if all such events did occur.

         C. WHEREAS, the parties now desire to amend the Stock Purchase
Agreement, in order to modify the events which shall trigger the payment of such
conditional payments.

         NOW, THEREFORE, in consideration of the foregoing and the mutual
covenants and conditions hereinafter contained, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged,
Buyer and the Shareholders agree as follows:

         1. Modification of Section 2.3(a)(iii) Event Which Triggers Conditional
Payments.

         At the end of Section 2.3(a)(iii) of the Stock Purchase Agreement, the
following provision shall be added:

         IN THE EVENT THAT COMPLETION OF DEVELOPMENT (ENGINEERING RELEASE) OF
         THE PRODUCT CODE-NAMED "ASAP OFFICE" OCCURS PRIOR TO THE DATE THAT THE
         ASAP PRODUCT'S CUMULATIVE SELL-THROUGH UNITS EXCEED 50,000 UNITS SOLD
         OR LICENSED, PROVIDED THAT COMPLETION OF DEVELOPMENT OF SUCH PRODUCT
         OCCURS NO LATER THAN EIGHTEEN MONTHS FOLLOWING THE FIRST CUSTOMER
         SHIPMENT DATE OF THE FIRST ASAP PRODUCT, THEN BUYER WILL CAUSE THE
         ESCROW AGENT TO PAY TO THE SHAREHOLDERS 70% OF THIS MILESTONE PAYMENT
         ($175,000) UPON SUCH COMPLETION OF DEVELOPMENT (ENGINEERING RELEASE) OF
         THE PRODUCT CODE-NAMED "ASAP OFFICE," AND BUYER WILL CAUSE THE ESCROW
         AGENT TO PAY TO THE SHAREHOLDERS THE REMAINDER OF THIS MILESTONE
         PAYMENT ($75,000) UPON THE DATE THAT CUMULATIVE SELL-THROUGH UNITS OF
         THE COMPANY'S ASAP PRODUCTS AND ANY OTHER PRODUCT DERIVATIVE THAT
         INCORPORATES THE SMARTSLIDE TECHNOLOGY, TOGETHER EXCEED 50,000 UNITS
         SOLD OR LICENSED.
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         2. Modification of Section 2.3(a)(iv) Event Which Triggers Conditional
Payments.

         Section 2.3(a)(iv) of the Stock Purchase Agreement shall be deleted in
full and replaced with the following:

         THE DATE THAT CUMULATIVE SELL-THROUGH UNITS OF THE COMPANY'S ASAP
         PRODUCT, THE SECOND PRODUCT AND ANY OTHER PRODUCT DERIVATIVE THAT
         INCORPORATES THE SMARTSLIDE TECHNOLOGY, TOGETHER, BY BUYER AND ITS
         AFFILIATES AND LICENSEES EXCEED 75,000 UNITS SOLD OR LICENSED, PROVIDED
         THAT THIS MILESTONE IS ACHIEVED NO LATER THAN 36 MONTHS FOLLOWING THE
         FIRST CUSTOMER SHIPMENT DATE OF THE COMPANY'S FIRST ASAP PRODUCT. IN
         THE EVENT THAT COMPLETION OF DEVELOPMENT (ENGINEERING RELEASE) OF A
         REVENUE-GENERATING "CONFERENCING" PRODUCT CODE- NAMED "JADE" OCCURS
         PRIOR TO THE DATE THAT CUMULATIVE SELL-THROUGH UNITS OF THE COMPANY'S
         ASAP PRODUCTS EXCEED 75,000 UNITS SOLD OR LICENSED, THEN BUYER SHALL
         CAUSE THE ESCROW AGENT TO PAY TO THE SHAREHOLDERS 70% OF THIS MILESTONE
         PAYMENT ($175,000) UPON SUCH COMPLETION OF DEVELOPMENT (ENGINEERING
         RELEASE) OF A REVENUE-GENERATING "CONFERENCING" PRODUCT CODE-NAMED
         "JADE", AND BUYER SHALL CAUSE THE ESCROW AGENT TO PAY TO THE
         SHAREHOLDERS THE REMAINDER OF THIS MILESTONE PAYMENT ($75,000) ON THE
         DATE THAT CUMULATIVE SELL- THROUGH UNITS OF THE COMPANY'S ASAP PRODUCTS
         EXCEED 75,000 UNITS SOLD OR LICENSED.

         3. Modification of Section 2.3(b) Event Which Triggers Conditional
Payments.

         Section 2.3(b) of the Stock Purchase Agreement shall be deleted in full
and replaced with the following:

         (i) BUYER SHALL PAY THE SHAREHOLDERS AN ADDITIONAL $175,000 UPON
         COMPLETION OF DEVELOPMENT (ENGINEERING RELEASE) OF THE PRODUCT
         CODE-NAMED "ASAP OFFICE", PROVIDED THAT COMPLETION OF DEVELOPMENT OF
         THIS PRODUCT IS ACHIEVED BY NO LATER THAN SEPTEMBER 30, 1996.

         (ii) BUYER SHALL PAY THE SHAREHOLDERS AN ADDITIONAL $175,000 UPON
         COMPLETION OF DEVELOPMENT (ENGINEERING RELEASE) OF A REVENUE-GENERATING
         "CONFERENCING" PRODUCT CODE-NAMED "JADE."

         (iii) BUYER SHALL PAY THE SHAREHOLDERS UP TO AN ADDITIONAL $150,000 IF
         CUMULATIVE REVENUES TO BUYER AND ITS AFFILIATES FROM THE SALE OF
         SELL-THROUGH UNITS OF THE ASAP PRODUCT, THE SECOND PRODUCT AND ANY
         OTHER PRODUCT DERIVATIVE THAT INCORPORATES THE SMARTSLIDE TECHNOLOGY,
         TOGETHER, BY BUYER, ITS AFFILIATES AND LICENSEES EQUAL OR EXCEED AN
         AGGREGATE OF $18,000,000 (THE "SALES MINIMUM") DURING THE THREE-YEAR
         PERIOD FOLLOWING THE FIRST CUSTOMER SHIPMENT DATE OF THE COMPANY'S
         FIRST ASAP PRODUCT, AS FOLLOWS: BUYER WILL HAVE THE OBLIGATION TO PAY
         THE SHAREHOLDERS AS SET FORTH BELOW IN CASH OR BY
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         CHECK OR BY WIRE TRANSFER (a) $21,429 FOLLOWING THE ACHIEVEMENT OF THE
         SALES MINIMUM AND (b) AN ADDITIONAL $21,429 FOLLOWING THE ACHIEVEMENT
         OF EACH ADDITIONAL $1,000,000 OF REVENUES FROM THE SALE OF SELL-THROUGH
         UNITS, UP TO A MAXIMUM PAYMENT BY BUYER TO THE SHAREHOLDERS OF $150,000
         UPON THE ACHIEVEMENT OF AT LEAST $25,000,000 OF REVENUES TO BUYER AND
         ITS AFFILIATES FROM THE SALE OR LICENSE OF CUMULATIVE SELL-THROUGH
         UNITS WITHIN SUCH THREE-YEAR PERIOD. SUCH ADDITIONAL PAYMENTS PURSUANT
         TO THIS SECTION 2.3(b)(iii) SHALL: (a) BE MADE BY BUYER WITHIN
         FORTY-FIVE (45) DAYS OF THE DATE FOLLOWING EACH OF THE THREE
         ANNIVERSARIES OF THE FIRST CUSTOMER SHIPMENT DATE IN WHICH SUCH
         ADDITIONAL PAYMENTS SHALL HAVE ACCRUED IN FAVOR OF THE SHAREHOLDERS;
         AND (b) BE ACCOMPANIED BY A STATEMENT SETTING FORTH IN REASONABLE
         DETAIL THE CUMULATIVE REVENUE TO THE COMPANY OF SELL-THROUGH UNITS OF
         SUCH PRODUCTS. SHAREHOLDERS SHALL HAVE THE RIGHT, AT THEIR COST, TO
         HAVE AN INDEPENDENT AUDITOR OF SHAREHOLDERS' CHOICE PERFORM AN AUDIT OF
         THE BOOKS AND FINANCIAL RECORDS OF BUYER AND ITS AFFILIATES TO VERIFY
         THE ACCURACY AND COMPLETENESS OF PAYMENTS PURSUANT TO THIS SECTION
         2.3(b)(iii) ON REASONABLE NOTICE TO BUYER DURING BUYER'S BUSINESS
         HOURS; PROVIDED THAT SUCH AUDITS SHALL OCCUR DURING THE THREE-MONTH
         PERIOD FOLLOWING THE END OF EACH ANNIVERSARY OF THE FIRST CUSTOMER
         SHIPMENT DATE.

         4. Effect of Amendment.

         Except as expressly provided herein, all other provisions, terms and
conditions of the Stock Purchase Agreement shall remain in full force and
effect.

         IN WITNESS WHEREOF, the parties hereto have duly executed this
Amendment effective as of the date first written above.


THE SHAREHOLDERS:                                BUYER:
                                                 SOFTWARE PUBLISHING CORPORATION

By: /s/ Daniel J. Fraisl                         By: /s/ Irfan Salim
    ---------------------------                      ---------------------------
    Daniel J. Fraisl                                 Irfan Salim,
                                                     President and C.E.O.

By: /s/ Carl Meyer
    ---------------------------
    Carl Meyer


By: /s/ Anthony N. Hoeber
    ---------------------------
    Anthony N. Hoeber