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                                                                   EXHIBIT 10.21

                            SECURED PROMISSORY NOTE


$1,048,826.34                                           Pittsburgh, Pennsylvania

                                                   Dated as of December 22, 1999


        FOR VALUE RECEIVED, the undersigned, JOSEPH WHANG ("Borrower"), promises
to pay to the order of PROGRAPH SYSTEMS, INC., a Pennsylvania corporation (the
"Company"), the principal sum of One Million, Forty Eight Thousand, Eight
Hundred Twenty-six Dollars and thirty-four Cents ($1,048,826.34) with interest
from the date hereof on the unpaid balance as specified herein. The entire
unpaid balance of principal and interest shall be due and payable, on the
earlier to occur of (1) Five (5) years from date of this note, (2) breach of the
Pledge Agreement dated the date hereof between the Company and Borrower, or (3)
a date specified in a written notice provided by Borrower to the Company setting
forth a date for repayment at least 5 business days after the date of such
notice.

        The interest rate on this note shall be an annual rate of interest equal
to six percent (6%), compounded semiannually. Interest shall be computed on the
basis of a year of 365 days and the actual number of days elapsed, except that
interest shall not be computed on the day of full repayment of this note.
Interest not paid when due shall earn interest at the rate specified above.

        If payment is not made when due, and if action is instituted on this
note, the undersigned agrees to pay the Company reasonable attorneys' fees and
costs of suit, as fixed by court in connection with the collection of the
outstanding amounts due under this note.

        The undersigned shall have the right to prepay all or any part of the
unpaid principal amount of this note, without premium, at any time prior to the
maturity hereof.


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        This note is originally secured by a pledge of shares of Common Stock of
the Company pursuant to a Pledge Agreement of even date herewith, which is on
file with the Secretary of the Company.

        If one or more of the provisions hereof shall be declared or held to be
invalid, illegal, or unenforceable in any respect in any jurisdiction, the
validity, legality and enforceability of the remaining provisions hereof shall
not in any way be affected or impaired thereby and any such declaration or
holding shall not invalidate or render unenforceable such provision in any other
jurisdiction.

        In case the note shall become mutilated or defaced, or be destroyed,
lost or stolen, the Borrower shall execute and deliver a new note of like
principal amount in exchange and substitution for the mutilated or defaced note,
or in lieu of and in substitution for the destroyed, lost or stolen note. In the
case of a mutilated or defaced note, the Company shall surrender such note to
the Borrower. In the case of any destroyed, lost or stolen note, the Company
shall furnish to the Borrower evidence to its satisfaction of the destruction,
loss or theft of such note.

        Notwithstanding anything to the contrary herein, in the event the value
of the Shares secured by the Pledge Agreement is insufficient to pay the full
amount due and owing hereunder, the Company may seek reimbursement from Borrower
for any deficiency, plus all interest accrued from the date of this note to the
due date as determined pursuant to the first paragraph of this note.

        This note shall be governed by and construed in accordance with the laws
of the Commonwealth of Pennsylvania, without regard to Pennsylvania choice of
law provisions.


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        IN WITNESS WHEREOF, the undersigned has signed, dated and delivered this
note as of the date and year first above written.



                                             /s/ Joseph Whang
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                                            Joseph Whang


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