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                                                                   EXHIBIT 10.10


                           ENTRUST TECHNOLOGIES INC.

                AMENDED AND RESTATED 1996 STOCK INCENTIVE PLAN

1.   Purpose
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     The purpose of this Amended and Restated 1996 Stock Incentive Plan (the
"Plan") of Entrust Technologies Inc., a Maryland corporation (the "Company"), is
to advance the interests of the Company's stockholders by enhancing the
Company's ability to attract, retain and motivate persons who make (or are
expected to make) important contributions to the Company by providing such
persons with equity ownership opportunities and performance-based incentives and
thereby better aligning the interests of such persons with those of the
Company's stockholders.  Except where the context otherwise requires, the term
"Company" shall include any present or future subsidiary corporations of Entrust
Technologies Inc. as defined in Section 424(f) of the Internal Revenue Code of
1986, as amended, and any regulations promulgated thereunder (the "Code").

2.   Eligibility
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     All of the Company's employees, officers, directors, consultants and
advisors are eligible to be granted options, restricted stock, or other stock-
based awards (each, an "Award") under the Plan.  Any person who has been granted
an Award under the Plan shall be deemed a "Participant."

3.   Administration, Delegation
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     a.   Administration by Board of Directors.  The Plan will be administered
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by the Board of Directors of the Company (the "Board"). The Board shall have
authority to grant Awards and to adopt, amend and repeal such administrative
rules, guidelines and practices relating to the Plan as it shall deem advisable.
The Board may correct any defect, supply any omission or reconcile any
inconsistency in the Plan or any Award in the manner and to the extent it shall
deem expedient to carry the Plan into effect and it shall be the sole and final
judge of such expediency. All decisions by the Board shall be made in the
Board's sole discretion and shall be final and binding on all persons having or
claiming any interest in the Plan or in any Award. No director or person acting
pursuant to the authority delegated by the Board shall be liable for any action
or determination relating to or under the Plan made in good faith.

     b.   Delegation to Executive Officers.  To the extent permitted by
          --------------------------------
applicable law, the Board may delegate to one or more executive officers of the
Company the power to make Awards and exercise such other powers under the Plan
as the Board may determine, provided that the Board shall fix the maximum number
of shares subject to Awards and the maximum number of shares for any one
Participant to be made by such executive officers.

     c.   Appointment of Committees.  To the extent permitted by applicable law,
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the Board may delegate any or all of its powers under the Plan to one or more
committees or subcommittees of the Board (a "Committee"). If and when the Series
A Common Stock, $.01 par value per share, of the Company (after giving effect to
the redesignation of the Company's Series A Common Stock into Common Stock upon
the filing of Articles of Amendment and
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Restatement, the "Common Stock") is registered under the Securities Exchange Act
of 1934 (the "Exchange Act"), the Board shall appoint one such Committee of not
less than two members, each member of which shall be an "outside director"
within the meaning of Section 162(m) of the Code and a "non-employee director"
as defined in Rule 16b-3 promulgated under the Exchange Act. All references in
the Plan to the "Board" shall mean the Board or a Committee of the Board or the
executive officer referred to in Section 3(b) to the extent that the Board's
powers or authority under the Plan have been delegated to such Committee or
executive officer.

4.   Stock Available for Awards
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     a.   Number of Shares.  Subject to adjustment under Section 4(c), Awards
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may be made under the Plan for up to 9,600,000 shares of Common Stock (after
giving effect to the four-for-one split of the Common Stock in the form of a
stock dividend declared by the Board on June 15, 1998 (the "Split")). If any
Award expires or is terminated, surrendered or canceled without having been
fully exercised or is forfeited in whole or in part or results in any Common
Stock not being issued, the unused Common Stock covered by such Award shall
again be available for the grant of Awards under the Plan, subject, however, in
the case of Incentive Stock Options (as hereinafter defined), to any limitation
required under the Code. Shares issued under the Plan may consist in whole or in
part of authorized but unissued shares or treasury shares.

     b.   Per-Participant Limit.  Subject to adjustment under Section 4(c), for
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Awards granted after the Common Stock is registered under the Exchange Act, the
maximum number of shares with respect to which an Award may be granted to any
Participant under the Plan shall be 5,000,000 per calendar year (after giving
effect to the Split). The per-participant limit described in this Section 4(b)
shall be construed and applied consistently with Section 162(m) of the Code.

     c.   Adjustment to Common Stock.  In the event of any stock split, stock
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dividend, recapitalization, reorganization, merger, consolidation, combination,
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, (i) the number and class of securities available
under this Plan, (ii) the number and class of security and exercise price per
share subject to each outstanding option, (iii) the repurchase price per
security subject to each outstanding Restricted Stock Award and (iv) the terms
of each other outstanding stock-based Award shall be appropriately adjusted by
the Company (or substituted Awards may be made, if applicable) to the extent the
Board shall determine, in good faith, that such an adjustment (or substitution)
is necessary and appropriate.  If this Section 4(c) applies and Section 8(e)(i)
also applies to any event, Section 8(e)(i) shall be applicable to such event,
and this Section 4(c) shall not be applicable.

5.   Stock Options
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     a.   General.  The Board may grant options to purchase Common Stock
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(each, an "Option") and determine the number of shares of Common Stock to be
covered by each option, the exercise price of each option and the conditions and
limitations applicable to the exercise of each option, including conditions
relating to applicable federal or state securities laws, as it considers
necessary or advisable. An option which is not intended to be an Incentive Stock
Option (as hereinafter defined) shall be designated a "Nonstatutory Stock
Option."

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     b.   Incentive Stock Options.  An Option that the Board intends to be an
          -----------------------
"incentive stock option" as defined in Section 422 of the Code (an "Incentive
Stock option") shall only be granted to employees of the Company and shall be
subject to and shall be construed consistently with the requirements of Section
422 of the Code.  The Company shall have no liability to a Participant, or any
other party, if an Option (or any part thereof) which is intended to be an
Incentive Stock Option is not an Incentive Stock Option.

     c.   Exercise Price.  The Board shall establish the exercise price at the
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time each Option is granted and specify it in the applicable option agreement.

     d.   Duration of Options.  Each option shall be exercisable at such times
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and subject to such terms and conditions as the Board may specify in the
applicable option agreement.

     e.   Exercise of Option.  Options may be exercised only by delivery to the
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company of a written notice of exercise signed by the proper person together
with payment in full as specified in Section 5(f) for the number of shares for
which the Option is exercised.

     f.   Payment Upon Exercise.  Common Stock purchased upon the exercise of an
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option granted under the Plan shall be paid for as follows:

          i.    in cash or by check, payable to the order of the Company;

          ii.    except as the Board may otherwise provide in an option
Agreement, delivery of an irrevocable and unconditional undertaking by a
creditworthy broker to deliver promptly to the Company sufficient funds to pay
the exercise price, or 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;

          iii.   to the extent permitted by the Board and explicitly provided in
an Option Agreement (i) by delivery of shares of Common Stock owned by the
Participant valued at their fair market value as determined by the Board in good
faith ("Fair Market Value"), which Common Stock was owned by the Participant at
least six months prior to such delivery, (ii) by delivery of a promissory note
of the Participant to the Company on terms determined by the Board, or (iii) by
payment of such other lawful consideration as the Board may determine; or

          iv.    any combination of the above permitted forms of payment.

6.   Restricted Stock
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     a.   Grants.  The Board may grant Awards entitling recipients to acquire
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shares of Common Stock, subject to the right of the Company to repurchase all or
part of such shares at their issue price or other stated or formula price (or to
require forfeiture of such shares if issued at no cost) from the recipient in
the event that conditions specified by the Board in the applicable Award are not
satisfied prior to the end of the applicable restriction period or periods
established by the Board for such Award (each, "Restricted Stock Award").

     b.   Terms and Conditions.  The Board shall determine the terms and
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conditions of any such Restricted Stock Award, including the conditions for
repurchase (or forfeiture) and the

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issue price, if any. Any stock certificates issued in respect of a Restricted
Stock Award shall be registered in the name of the Participant and, unless
otherwise determined by the Board, deposited by the Participant, together with a
stock power endorsed in blank, with the Company (or its designee). At the
expiration of the applicable restriction periods, the Company (or such designee)
shall deliver the certificates no longer subject to such restrictions to the
Participant or if the Participant has died, to the beneficiary designated, in a
manner determined by the Board, by a Participant to receive amounts due or
exercise rights of the Participant in the event of the Participant's death (the
"Designated Beneficiary"). In the absence of an effective designation by a
Participant, Designated Beneficiary shall mean the Participant's estate.

7.   Other Stock-Based Awards
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     The Board shall have the right to grant other Awards based upon the Common
Stock having such terms and conditions as the Board may determine, including the
grant of shares based upon certain conditions, the grant of securities
convertible into Common Stock and the grant of stock appreciation rights.

8.   General Provisions Applicable to Awards
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     a.   Transferability of Awards.  Except as the Board may otherwise
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determine or provide in an Award, Awards shall not be sold, assigned,
transferred, pledged or otherwise encumbered by the person to whom they are
granted, either voluntarily or by operation of law, except by will or the laws
of descent and distribution, and, during the life of the Participant, shall be
exercisable only by the Participant. References to a Participant, to the extent
relevant in the context, shall include references to authorized transferees.

     b.   Documentation.  Each Award under the Plan shall be evidenced by a
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written instrument in such form as the Board shall determine. Each Award may
contain terms and conditions in addition to those set forth in the Plan.

     c.   Board Discretion.  Except as otherwise provided by the Plan, each type
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of Award may be made alone or in addition or in relation to any other type of
Award. The terms of each type of Award need not be identical, and the Board need
not treat Participants uniformly.

     d.   Termination of Status.  The Board shall determine the effect on an
          ---------------------
Award of the disability, death, retirement, authorized leave of absence or other
change in the employment or other status of a Participant and the extent to
which, and the period during which, the Participant, the Participant's legal
representative, conservator, guardian or Designated Beneficiary may exercise
rights under the Award.

     e.   Acquisition Events
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          i.   Consequences of Acquisition Events.  Upon the occurrence of an
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Acquisition Event (as defined below), or the execution by the Company of any
agreement with respect to an Acquisition Event, the Board shall take any one or
more of the following actions with respect to then outstanding Awards: (i)
provide that outstanding Options shall be assumed, or equivalent Options shall
be substituted, by the acquiring or succeeding corporation (or an affiliate
thereof), provided that any such Options substituted for Incentive Stock options
shall

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satisfy, in the determination of the Board, the requirements of Section 424(a)
of the Code; (ii) upon written notice to the Participants, provide that all then
unexercised Options will become exercisable in full and will terminate
immediately prior to the consummation of such Acquisition Event, except to the
extent exercised by the Participants within a specified period following the
date of such notice; (iii) in the event of an Acquisition Event under the terms
of which holders of Common Stock will receive upon consummation thereof a cash
payment for each share of Common Stock surrendered pursuant to such Acquisition
Event (the "Acquisition Price"), provide that all outstanding Options shall
terminate upon consummation of the Acquisition Event and that Participants shall
receive, in exchange therefor, a cash payment equal to the amount (if any) by
which (A) the Acquisition Price multiplied by the number of shares of Common
Stock subject to such outstanding Options (whether or not then exercisable),
exceeds (B) the aggregate exercise price of such options; (iv) provide that all
Restricted Stock Awards then outstanding shall become free of all restrictions
prior to the consummation of the Acquisition Event; and (v) provide that any
other stock-based Awards outstanding (A) shall become exercisable, realizable or
vested in full, or shall be free of all conditions or restrictions, as
applicable to each such Award, prior to the consummation of the Acquisition
Event, or (B) shall be assumed, or equivalent Awards shall be substituted, by
the acquiring or succeeding corporation (or an affiliate thereof).

     An "Acquisition Event" shall mean:  (a) 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 60% 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; (b) any sale of all or substantially all of the assets
of the Company; (c) the complete liquidation of the Company; or (d) the
acquisition of "beneficial ownership" (as defined in Rule 13d-3 under the
Exchange Act) of securities of the Company representing 60% 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, 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.  Notwithstanding the foregoing, the exercise
of the Triggering event option (as defined in the Company's Articles of
Incorporation) by the holders of the Company's Series B Common Stock shall not
be deemed to be an Acquisition Event.

          ii.  Assumption of Options Upon Certain Events.  The Board may grant
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Awards under the Plan in substitution for stock and stock-based awards held by
employees of another corporation who become employees of the Company as a result
of a merger or consolidation of the employing corporation with the Company or
the acquisition by the Company of property or stock of the employing
corporation. The substitute Awards shall be granted on such terms and conditions
as the Board considers appropriate in the circumstances.

     f.   Withholding.  Each Participant shall pay to the Company, or make
provision satisfactory to the Board for payment of, any taxes required by law to
be withheld in connection with Awards to such Participant no later than the date
of the event creating the tax liability. The

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Board may allow Participants to satisfy such tax obligations in whole or in part
in shares of Common Stock, including shares retained from the Award creating the
tax obligation, valued at their Fair Market Value. The Company may, to the
extent permitted by law, deduct any such tax obligations from any payment of any
kind otherwise due to a Participant.

     g.   Amendment of Award.  The Board may amend, modify or terminate any
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outstanding Award, including but not limited to, substituting therefor another
Award of the same or a different type, changing the date of exercise or
realization, and converting an Incentive Stock Option to a Nonstatutory Stock
option, provided that the Participant's consent to such action shall be required
unless the Board determines that the action, taking into account any related
action, would not materially and adversely affect the Participant.

     h.   Conditions on Delivery of Stock.  The Company will not be obligated to
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deliver any shares of Common Stock pursuant to the Plan or to remove
restrictions from shares previously delivered under the Plan until (i) all
conditions of the Award have been met or removed to the satisfaction of the
Company, (ii) in the opinion of the Company's counsel, all other legal matters
in connection with the issuance and delivery of such shares have been satisfied,
including any applicable securities laws and any applicable stock exchange or
stock market rules and regulations, and (iii) the Participant has executed and
delivered to the Company such representations or agreements as the Company may
consider appropriate to satisfy the requirements of any applicable laws, rules
or regulations.

     i.   Acceleration.  The Board may at any time provide that any Options
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shall become immediately exercisable in full or in part, that any Restricted
Stock Awards shall be free of all restrictions or that any other stock-based
Awards may become exercisable in full or in part or free of some or all
restrictions or conditions, or otherwise realizable in full or in part, as the
case may be.

9.   Miscellaneous
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     a.   No Right To Employment or Other Status.  No person shall have any
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claim or right to be granted an Award, and the grant of an Award shall not be
construed as giving a Participant the right to continued employment or any other
relationship with the Company. The Company expressly reserves the right at any
time to dismiss or otherwise terminate its relationship with a Participant free
from any liability or claim under the Plan, except as expressly provided in the
applicable Award.

     b.   No Rights As Stockholder.  Subject to the provisions of the applicable
          ------------------------
Award, no Participant or Designated Beneficiary shall have any rights as a
stockholder with respect to any shares of Common Stock to be distributed with
respect to an Award until becoming the record holder of such shares.

      c.  Effective Date and Term of Plan.  The Plan shall become effective on
the date on which it is adopted by the Board, but no Award granted to a
Participant designated as subject to Section 162(m) by the Board shall become
exercisable, vested or realizable, as applicable to such Award, unless and until
the Plan has been approved by the Company's stockholders. No Awards shall be
granted under the Plan after the completion of ten years from the earlier of (i)
the date on

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which the Plan was adopted by the Board or (ii) the date the Plan was approved
by the Company's stockholders, but Awards previously granted may extend beyond
that date.

     d.   Amendment of Plan.  The Board may amend, suspend or terminate the Plan
          -----------------
or any portion thereof at any time, provided that no Award granted to a
Participant designated as subject to Section 162(m) by the Board after the date
of such amendment shall become exercisable, realizable or vested, as applicable
to such Award (to the extent that such amendment to the Plan was required to
grant such Award to a particular Participant), unless and until such amendment
shall have been approved by the Company's stockholders.

     e.   Stockholder Approval.  For purposes of this Plan, stockholder approval
          --------------------
shall mean approval by a vote of the stockholders in accordance with the
requirements of Section 162(m) of the Code.

     f.  Governing Law.  The provisions of the Plan and all Awards made
hereunder shall be governed by and interpreted in accordance with the laws of
the State of Maryland, without regard to any applicable conflicts of law.

                              Adopted by the Board of Directors on June 18, 1998


                              Approved by the Stockholders on July 7, 1998

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                                AMENDMENT NO. 1
                                    TO THE
                AMENDED AND RESTATED 1996 STOCK INCENTIVE PLAN
                                      OF
                           ENTRUST TECHNOLOGIES INC.


     The Amended and Restated 1996 Stock Incentive Plan (the "Plan") of Entrust
Technologies Inc. is hereby amended as follows (capitalized terms used herein
and not defined herein shall have the respective meanings ascribed to such terms
in the Plan):

1.   Section 5(e) of the Plan shall be deleted in its entirety and replaced with
the following:

          "(e) Exercise of Option.  Options may be exercised by delivery to the
               ------------------
     Company of a written notice of exercise signed by the proper person or by
     any other form of notice (including electronic notice) approved by the
     Board together with payment in full as specified in Section 5(f) for the
     number of shares for which the Option is exercised."

2.   Section 8(b) of the Plan shall be deleted in its entirety and replaced with
the following:

          "(b) Documentation.  Each Award shall be evidenced by a written
               -------------
     instrument in such form as the Board shall determine, it being understood
     that an electronic form of Award shall be deemed to be a written instrument
     for purposes of the Plan.  Each Award may contain terms and conditions in
     addition to those set forth in the Plan."

3.   Except as aforesaid, the Plan shall remain in full force and effect.

                    Adopted by the Board of Directors on December 10, 1999
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                                AMENDMENT NO. 2
                                    TO THE
                AMENDED AND RESTATED 1996 STOCK INCENTIVE PLAN
                                      OF
                           ENTRUST TECHNOLOGIES INC.


     The Amended and Restated 1996 Stock Incentive Plan, as amended (the
"Plan"), of Entrust Technologies Inc. is hereby further amended as follows (all
capitalized terms used herein and not defined herein shall have the respective
meanings ascribed to such terms in the Plan):

1.   The first sentence of Section 4(a) of the Plan shall be deleted in its
entirety and replaced with the following:

          "(a) Number of Shares.  Subject to adjustment under Section 4(c),
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     Awards may be made under the Plan for up to 14,600,000 shares of Common
     Stock, plus an annual increase to be added on each of January 1, 2001 and
     January 1, 2002, equal to the lower of (i) 5% of the total number of
     outstanding shares of Common Stock on such date or (ii) a lesser amount
     determined by the Board; provided, however, that the maximum number of
     shares of Common Stock available for issuance hereunder shall be 26,000,000
     shares.  (The foregoing share numbers reflect a four-for-one split of the
     Common Stock which was effected in the form of a stock dividend declared by
     the Board on June 15, 1998.)"


2.   Except as aforesaid, the Plan shall remain in full force and effect.


                        Adopted by the Board of Directors on January 28, 2000

                        Approved by the Stockholders on April 27, 2000