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                                                                    EXHIBIT 10.2
                                                                    ------------

                           ENTRUST TECHNOLOGIES INC.

                  Special Nonstatutory Stock Option Agreement
                  -------------------------------------------


1.   Grant of Option.
     ---------------

     This Agreement evidences the grant by Entrust Technologies Inc., a Maryland
corporation (the "Company"), on April 22, 2001 (the "Grant Date") to F. William
Conner, President and Chief Executive Officer of the Company (the "Executive"),
of an option to purchase (this "Option"), in whole or in part, on the terms
provided herein, and on the terms provided in the Employment Agreement dated
April 22, 2001 between the Company and the Executive (the "Employment
Agreement"), a total of 2,000,000 shares (the "Shares") of common stock, $0.01
par value per share, of the Company (the "Common Stock") at $6.87 per share (the
"Option Price").  Unless earlier terminated, this Option shall expire on the
tenth anniversary of the Grant Date (the "Final Exercise Date").  It is intended
that the Option shall not be an incentive stock option as defined in Section 422
of the Internal Revenue Code of 1986, as amended (the "Code").

2.   Vesting Schedule.
     ----------------

     (a) Regular Vesting.  The Option shall vest as follows:
         ---------------

          (i)   800,000 Shares (the "Time Shares") at a rate of 1/24th of such
     amount upon each complete month of continued employment following the
     second anniversary of the Grant Date;

          (ii)  550,000 Shares (the "First Performance Shares") upon the earlier
     of (A) the fifth anniversary of the Grant Date or (B) the first day on
     which the closing price of the Company's Common Stock on the Nasdaq
     National Market ("Nasdaq"), as reported by Nasdaq, shall have been at least
     $15.00 per share for at least 50 out of 60 consecutive trading days
     (including the day of vesting pursuant to this clause (ii)), provided that,
     in either case (A) or (B), the Executive remains employed with the Company
     as of such date; and

          (iii) 650,000 Shares (the "Second Performance Shares") upon the
     earlier of (A) the fifth anniversary of the Grant Date or (B) the first day
     on which the closing price of the Company's Common Stock on Nasdaq, as
     reported by Nasdaq, shall have been at least $25.00 per share for at least
     50 out of 60 consecutive trading days (including the day of vesting
     pursuant to this clause (iii)), provided that, in either case (A) or (B),
     the Executive remains employed with the Company as of such date.

     (b) Accelerated Vesting.  Upon the occurrence of an Acquisition Event (as
         -------------------
defined below), or upon termination of the Executive's employment by the Company
for any reason other than for Cause (as defined in the Employment Agreement)
within 120 days before either an
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Acquisition Event or the announcement of an Acquisition Event, the vesting
schedule with respect to the Time Shares shall be accelerated so that all of the
Time Shares that would otherwise have first become exercisable on any vesting
date scheduled to occur on or after the date of such Acquisition Event shall
become vested immediately prior to such Acquisition Event. If an Acquisition
Event involves the purchase or exchange of the Company's Common Stock at a price
per share equal to or greater than one or both of the target prices described in
clauses (ii) and (iii) of Section 2(a) hereof, the vesting schedule with respect
to the First Performance Shares and, if applicable, the Second Performance
Shares shall be accelerated so that all of the First Performance Shares and, if
applicable, the Second Performance Shares that would otherwise have first become
exercisable on any vesting date scheduled to occur on or after the date of such
Acquisition Event shall become vested immediately prior to such Acquisition
Event. For purposes of this Agreement, an "Acquisition Event" shall mean:

          (i)   any merger or consolidation which would result in the voting
     securities of the Company outstanding immediately prior thereto continuing
     to represent (either by remaining outstanding or by being converted into
     voting securities of the surviving or acquiring entity) less than 70% of
     the combined voting power of the voting securities of the Company or such
     surviving or acquiring entity outstanding immediately after such merger or
     consolidation;

          (ii)  any sale of all or substantially all of the assets of the
     Company;

          (iii) the complete liquidation of the Company; or

          (iv)  the acquisition of "beneficial ownership" (as defined in Rule
     13d-3 under the Securities Exchange Act of 1934 (the "Exchange Act")) of
     securities of the Company representing 30% or more of the combined voting
     power of the Company's then outstanding securities (other than through an
     acquisition of securities directly from the Company) by any "person" (as
     such term is used in Sections 13(d) and 14(d) of the Exchange Act) other
     than the Company, Nortel Networks.com, any trustee or other fiduciary
     holding securities under an employee benefit plan of the Company, or any
     corporation owned directly or indirectly by the stockholders of the Company
     in substantially the same proportion as their ownership of stock of the
     Company.


3.   Exercise of Option.
     ------------------

     (a) Form of Exercise.
         ----------------

          (i)   Subject to Sections 3(a)(ii) and (iii) below, each election to
     exercise this Option shall be in writing, signed by the Executive, and
     received by the Company at its principal office, accompanied by this
     Agreement and payment in full, by cashier's or certified check payable to
     the order of the Company, of the exercise price and required tax
     withholding.

          (ii)  In lieu of exercising this Option for cash pursuant to the
     immediately preceding clause, the Executive may, subject to the discretion
     of the Company's Board of Directors (or the Compensation Committee of the
     Company's Board of Directors), which

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     approval shall not be required if the Company's Common Stock is not listed
     on the Nasdaq Stock Market ("Nasdaq") or any other exchange at the time of
     the proposed exercise, elect to receive Shares equal to the value of this
     Option (or the portion thereof being cance led) by surrender of this Option
     at the principal office of the Company and specifications of such election
     on the Notice of Election, in which event the Company shall issue to the
     Executive a number of Shares computed using the following formula:


         X = Y(A-B-C)
             -------
                A

     Where      X   = the number of Shares to be issued to the Executive.

                Y   = the number of Shares for which this Option is then being
                      exercised.

                A   = the fair market value of one share of the Company's
                      Common Stock.

                B   = the Option Price (as adjusted to the date of such
                      calculation).

                C   = the applicable per Share tax incurred by the Executive by
                      reason of such exercise, computed in the manner set forth
                      in Section 3(a) of the Employment Agreement.

                (iii)  The Participant may pay for shares of the Company's
     Common Stock purchased upon exercise of this option by (A) delivery of an
     irrevocable and unconditional undertaking by a creditworthy broker to
     deliver promptly to the Company sufficient funds to pay the exercise price
     and any required tax withholding, (B) delivery by the Participant to the
     Company of a copy of irrevocable and unconditional instructions to a
     creditworthy broker to deliver promptly to the Company cash or a check
     sufficient to pay the exercise price and any required tax withholding, or
     (C) when the Company's Common Stock is registered under the Securities
     Exchange Act of 1934, as amended, delivery of shares of the Company's
     Common Stock owned by the Executive valued at their fair market value (as
     defined below), provided (A) such method of payment is then permitted under
     applicable law and (B) such shares, if acquired directly from the Company,
     were owned by the Executive at least six months prior to such delivery;

                (iv)   For purposes of this Section 3, the fair market value of
     the Company's Common Stock shall mean: (A) when the Company's Common Stock
     is listed on Nasdaq or any other exchange, the closing sale price of the
     Company's Common Stock quoted on Nasdaq or any other exchange, whichever is
     applicable, as published in The Wall Street Journal for the day on which
                                 -----------------------
     the option is exercised and (B) when the Company's Common Stock is not
     listed on Nasdaq or any other exchange, the fair market value of the
     Company's Common Stock as determined by the Company's Board of Directors
     (or Compensation Committee of the Company's Board of Directors) in good
     faith.

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  (b) Continuous Relationship with the Company Required.  Except as otherwise
      -------------------------------------------------
provided herein, this Option may not be exercised unless the Executive, at the
time he exercises this Option, is, and has been at all times since the Grant
Date, the President and Chief Executive Officer of the Company.

  (c) Termination by the Company Without Cause or by the Executive With Good
      ----------------------------------------------------------------------
Reason. If, prior to the Final Exercise Date, the Company terminates the
------
Executive's employment other than for Cause (as defined in the Employment
Agreement), death or disability, or the Executive terminates his employment for
Good Reason (as defined in the Employment Agreement), the vesting schedule
described in Section 2(a) hereof shall be accelerated such that this Option
shall immediately vest with respect to the additional Shares that would have
vested had the Executive been employed by the Company during the one-year period
commencing on such termination date; provided, however, that if such termination
occurs after the first 24 months of the Executive's employment with the Company,
such vesting schedule shall be further accelerated such that this Option shall
immediately vest with respect to the additional Shares that would have vested
had the Executive been employed by the Company during the period extending from
the 13th month following such termination date through and including the 18th
month following such termination date.  This Option, to the extent vested as
described in this Section 3(c), shall remain exercisable for 180 days following
the date on which the Executive's employment with the Company ceases (but in no
event after the Final Exercise Date).

  (d) Termination Upon Death or Disability.  If, prior to the Final Exercise
      ------------------------------------
Date, the Executive's employment with the Company is terminated due to his death
or disability (as defined in Section 4(c) of the Employment Agreement), (i) this
Option shall immediately vest with respect to the Time Shares that would have
vested had the Executive been employed by the Company during the one-year period
commencing on his death or disability, as the case may be, and (ii) the period
during which the performance targets described in clauses (ii) and (iii) of
Section 2(a) hereof may be met shall be extended for twelve months following the
date on which the Executive's employment with the Company ceases.  This Option,
to the extent vested with respect to the Time Shares, shall be exercisable by
the Executive or his estate for twelve months following his death or disability
(but in no event after the Final Exercise Date).  This Option, to the extent
vested with respect to the First Performance Shares or Second Performance
Shares, shall be exercisable by the Executive or his estate for 180 days
following the date on which such shares vest (but in no event after the Final
Exercise Date).

  (e) Termination by the Company for Cause or by the Executive Without Good
      ---------------------------------------------------------------------
Reason.  If, prior to the Final Exercise Date, the Company terminates the
------
Executive's employment for Cause (as defined in the Employment Agreement), or
the Executive terminates his employment with the Company without Good Reason (as
defined in the Employment Agreement), the right to exercise this Option shall
terminate on the date on which the Executive's employment with the Company
ceases.

4.  Withholding.
    -----------

    No Shares will be issued pursuant to the exercise of this Option unless and
until the Executive pays to the Company, or makes provision satisfactory to the
Company for payment of,

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any federal, state or local withholding taxes required by law to be withheld in
respect of this Option.

5.  Nontransferability of Option.
    ----------------------------

    This Option may not be sold, assigned, transferred, pledged or otherwise
encumbered by the Executive, either voluntarily or by operation of law, except
by will or the laws of descent and distribution, and, during the lifetime of the
Executive, this Option shall be exercisable only by the Executive.

6.  Conditions on Delivery of Stock.
    -------------------------------

    Notwithstanding anything to the contrary in this Agreement, no Shares
purchased upon exercise of this Option, and no certificate representing such
Shares, shall be issued or delivered if (a) such Shares have not been admitted
to listing upon official notice of issuance on each stock exchange upon which
Shares of that class are then listed, or (b) in the opinion of counsel to the
Company, such issuance or delivery would (i) cause the Company to be in
violation of or to incur liability under any federal, state or other securities
law, or any requirement of any stock exchange listing agreement to which the
Company is a party, or any other requirement of law or of any administrative or
regulatory body having jurisdiction over the Company, or (ii) require
registration (apart from such registrations as have been theretofore completed
by the Company covering such shares) under any federal, state or other
securities or similar law.

7.  Adjustments.
    -----------

    In the event of any stock split, stock dividend, recapitalization,
reorganization, merger, consolidation, combination or exchange of shares,
liquidation, spin-off or other similar change in capitalization or event, or any
distribution to holders of Common Stock other than a normal cash dividend, the
number and class of security and exercise price per share subject to the
unexercised portion of this Option as well as the per share thresholds referred
to in Sections 2(a)(ii) and 2(a)(iii) hereof shall be proportionally adjusted.
If this Section 7 applies and Section 2(b) also applies to any event, Section
2(b) shall be applicable to such event, and this Section 7 shall not be
applicable.

8.  Continuation of Employment.
    --------------------------

    Neither this Agreement nor the Option shall confer upon the Executive any
right to continued employment by (or any other relationship with) the Company or
any subsidiary, affiliate or parent thereof, or limit in any respect the right
of the Company to terminate the Executive's employment or other relationship
with the Company or any subsidiary, affiliate or parent thereof, as the case may
be, at any time.

9.  Stockholder Rights.
    ------------------

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    No person or entity shall have any rights as a stockholder with respect to
any shares of Common Stock to be distributed with respect to this Option until
becoming the record holder of such shares.

10. Construction.
    ------------

    This Agreement is subject to, and shall be interpreted consistent with, the
terms of the Employment Agreement.

11. Governing Law.
    -------------

    This Agreement shall be governed by and construed in accordance with the
laws of the State of Maryland, but without regard to the principle of conflict
of laws thereof.  If any one or more provisions of this Agreement shall be found
to be illegal or unenforceable in any respect, the validity and enforceability
of the remaining provisions hereof shall not in any way be affected or impaired
thereby.

12. Successors and Assigns.
    ----------------------

    This Agreement shall inure to the benefit of and be binding upon the
Executive, the Company, their respective beneficiaries, heirs, executors,
administrators, legal representatives and guardians, and their permitted
successors and assigns.

13. Notices.
    -------

    All notices and other communications required or permitted hereunder shall
be in writing and deemed to have been received on the date of delivery if
delivered by hand or overnight express, or three days after the date of posting
if mailed by registered or certified mail, postage prepaid, addressed to the
Company at One Preston Park South, Suite 400, 4975 Preston Park Boulevard,
Plano, Texas 75093, and to the Executive at 6130 Tulip Lane, Dallas, Texas 75230
(or such other address to which the Company or the Executive hereby notifies the
other party hereto to send such notices and communications).  Such notices and
other communications shall not be considered delivered until actually received
or deemed received pursuant to this Section 13.

14. Amendment of Option.
    -------------------

    The Company may not amend or modify this Option without the consent of the
Executive, unless the Board of Directors of the Company determines that such
amendment or modification, taking into account any related action, would not
materially and adversely affect the Executive, in which case the Executive's
consent shall not be required.

                                     *****

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     IN WITNESS WHEREOF, the Company has caused this option to be executed under
its corporate seal by its duly authorized officer.  This Option shall take
effect as a sealed instrument.


                                        ENTRUST TECHNOLOGIES INC.


                                        By:  /s/ James A. Thomson
                                             ---------------------------
                                        Name:  James A. Thomson
                                             ---------------------------
                                        Title:  Chairman
                                             ---------------------------


AGREED TO AND ACCEPTED BY:

EXECUTIVE


/s/ F. William Conner
--------------------------------
F. William Conner

Address:  6130 Tulip Lane
          Dallas, Texas  75230

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