Document:

<PAGE>   1
                                                                    EXHIBIT 10.5

                          [ENTRUST TECHNOLOGIES LOGO]

                      ENTERPRISE AND CA SERVICES AGREEMENT

This Enterprise and CA Services Agreement ("Agreement") is made between:

Entrust Technologies Inc.                ZixIt Corporation
4975 Preston Park Blvd., Suite 400       2711 N. Haskell Ave., Suite 2850 LB 36
Plano, Texas, U.S.A. 75093               Dallas, Texas, U.S.A.  75204-2911
("Entrust")                              ("Customer")

This Agreement shall be effective November 6, 2000 ("Effective Date"). Entrust
and Customer agree that the following terms and conditions will apply to the
licenses and services provided under this Agreement and Schedules attached
hereto.

1.       DEFINITIONS

(a)      "AFFILIATE" of a party means any corporation or other entity that a
         party directly or indirectly controls. In this context, a party
         "controls" a corporation or other entity if it owns fifty percent (50%)
         or more of the voting rights for the board of directors or other
         mechanism of control for the corporation or other entity.

(b)      "APPLICATION" means a single software product from a single vendor
         (either an Entrust product or a third party product) used by an
         individual or device which performs a single function such as word
         processing or electronic mail. For greater certainty, a utility or
         multi-function program shall be considered to consist of multiple
         Applications.

(c)      "CA SERVICES" means those services described in Schedule C, (Section 2)
         which Customer may provide to CA Services Subscribers and CA Services
         Subscriber Users.

(d)      "CA SERVICES AGREEMENT" means a written agreement between Customer and
         a CA Services Subscriber to provide CA Services.

(e)      "CA SERVICES SOFTWARE" means the software listed in Schedule C,
         (Section 3).

(f)      "CA SERVICES SUBSCRIBER" means an entity meeting the requirements of
         Schedule C, (Section 1) which entity must have entered into a CA
         Services Agreement with Customer. Such entity shall be a CA Service
         Subscriber only for so long as such entity continues to contract for
         and receive CA Services.

(g)      "CA SERVICES SUBSCRIBER USER" in respect of a CA Service Subscriber (i)
         that is not a government or government entity, means a customer,
         supplier, or other such entity communicating with the CA Services
         Subscriber in regard to the business of the CA Services Subscriber,
         (ii) that is a government or government entity, means any employees
         within the government or government entity, unless Entrust agrees
         otherwise in writing.

(h)      "CERTIFICATE LICENSE" means a right to use a digital certificate issued
         by the Entrust/Authority software (or any connector add-on to the
         Entrust/Authority software). The maximum number of digital certificates
         issued by the Entrust/Authority software for each type of digital
         certificate is set by a Licensing String.

(i)      "CERTIFICATION AUTHORITY" means an entity or organization that (i)
         creates and signs digital certificates that contain among other things
         a subject's public key and other information that is intended to
         identify the subject, (ii) makes digital certificates available to
         facilitate verification of and communication with subjects named in
         such digital certificate, and (iii) creates and digitally signs
         certificate revocation lists and/or other forms of revocation
         information about digital certificates that have been revoked and which
         should no longer be used or relied upon.

(j)      "CLIENT ACCESS LICENSE (CAL)" means a user contained in a Single Data
         Set who is authorized to sign on and utilize the getAccess software.

(k)      "CLIENT SOFTWARE" means the Software listed under the heading "Client
         Software" in Schedule A for which the Enterprise has acquired the right
         to use under this Agreement in machine-readable object code form only
         and associated documentation.

(l)      "CONFIDENTIAL INFORMATION" means any business, marketing, technical,
         scientific or other information disclosed by either party (including
         its Affiliates) which, at the time of disclosure is designated as
         confidential (or like designation), is disclosed in

U.S. CASP 5.4                             1
October 24, 2000

<PAGE>   2

         circumstances of confidence, or would be understood by the parties (or
         its Affiliates), exercising reasonable business judgment, to be
         confidential.

(m)      "ENTERPRISE" means, collectively, the Customer and Affiliates of
         Customer.

(n)      "ENTRUST ENGINE" means a set of files included in an Entrust/Toolkit,
         which must be resident on the desktop or server to allow an
         Entrust-Ready Application to work. The set of files contains one or
         more functions that are compiled, linked and stored separately from the
         processes that use them. These files do not need to be compiled with
         the main application program. The operating system maps the engines, in
         the form of DLLs on the Windows platform or shared libraries on the
         unix platform, into the memory/address space of the calling application
         when the application is starting or while it is running.

(O)      "ENTRUST-READY APPLICATION" means any computer program created by
         Customer using an Entrust/Toolkit that does not contain any of the
         executable object code modules provided with an Entrust/Toolkit that
         implement an Entrust API or any of the Entrust functions including, but
         not limited to, encryption, digital signature, and any key management
         function, and revisions and updates thereto.

(p)      "INFRASTRUCTURE SOFTWARE" means the Software listed under the heading
         "Infrastructure Software" in Schedule A for which the Enterprise has
         acquired the right to use under this Agreement in machine-readable
         object code form only and associated documentation.

(q)      "LICENSING STRING" means a series of computer-generated characters
         provided to Customer by Entrust for the purpose of setting the number
         of Certificate Licenses or User Identities for an item of
         Infrastructure Software.

(r)      "SERVICES" means consulting, installation and training services
         provided by Entrust under the terms of this Agreement.

(s)      "SINGLE DATA SET" means a unique collection of user names in a
         repository (eg. a database) which is supported by the getAccess
         software. Replication of the identical collection of user names in a
         separate repository for development, testing, back up and load
         balancing purposes shall be considered the same Single Data Set. In
         addition, the occurrence of the same users or a subset of such users in
         a separate directory (e.g., LDAP Directory) used in combination with
         the repository is considered the same Single Data Set.

(t)      "SOFTWARE" means the Entrust computer software programs listed in
         Schedules A and C for which the Enterprise has acquired the right to
         use under this Agreement in machine-readable object code form only and
         associated documentation. If Enterprise elects to purchase Support, any
         Upgrades and Upissues provided to Enterprise pursuant to such Support
         shall be deemed to be Software for the purposes of this Agreement.

(u)      "SUPPORT" means Software maintenance, Upgrade and Upissue services as
         set forth in Schedule B of this Agreement.

(v)      "UPGRADE" means a subsequent release of existing Software, other than
         those reasonably designated as new products for which Entrust charges
         separately, which will generally contain new functionality and
         enhancements in addition to bug fixes. Upgrade releases will be
         designated by a change in the digit of the release number to the left
         of the decimal. e.g. 1.X to 2.Y.

(w)      "UPISSUE" means a subsequent release of existing Software which will
         generally contain bug-fixes and which will generally not contain major,
         new functionality. Upissue releases will be designated by a change in
         the digit of the release number to the right of the decimal. e.g. X.1
         to X.2.

(x)      "USER IDENTITY" means an electronic identity utilized by the
         Entrust/Authority software for interaction with Client Software. The
         maximum number of electronic identities recognized by the
         Entrust/Authority software is set by a Licensing String.

2.       ENTERPRISE AND CA SERVICES LICENSES

(a)      INFRASTRUCTURE SOFTWARE LICENSES FOR ENTERPRISE USE. Subject to the
         terms and conditions of this Agreement, Entrust hereby grants to
         Enterprise and Enterprise accepts a non-exclusive, non-transferable,
         internal license to use and copy Infrastructure Software to the extent
         of the number of copies of Infrastructure Software licensed to
         Enterprise and to the extent of the number of User Identities and
         Certificate Licenses set by the Licensing String(s) delivered to
         Enterprise with or for that copy of Infrastructure Software for
         internal communications within the Enterprise and for communications
         between Enterprise and third parties concerning Enterprise business
         other than CA Services ("Enterprise Use"). If the number of permitted
         User Identities or Certificate Licenses for a copy of Infrastructure
         Software is not controlled using a Licensing String, Enterprise shall
         use such copy of Infrastructure Software to the extent of the number of
         User Identities and Certificate Licenses permitted for use with such
         copy of Infrastructure Software pursuant to this Agreement. Enterprise
         may only use Licensing Strings provided by Entrust and only in
         conjunction with the copy of Infrastructure Software for which it was
         delivered. Enterprise may not copy or alter a Licensing String.

U.S. CASP 5.4                             2
October 24, 2000

<PAGE>   3
         If Customer licenses the getAccess software, Entrust hereby grants to
         Enterprise a non-exclusive, non-transferable, internal license for the
         number of Client Access Licenses acquired pursuant to this Agreement
         for use in a Single Data Set.

(b)      CLIENT SOFTWARE LICENSES AND DISTRIBUTION RIGHT FOR ENTERPRISE USE.
         Subject to the terms and conditions of this Agreement, Entrust hereby
         grants to the Enterprise and the Enterprise accepts a non-exclusive,
         non-transferable license to use and copy the number copies of Client
         Software licensed herein solely for Enterprise Use. Enterprise may
         distribute Client Software to third parties, provided, however, that:
         (i) the Client Software is provided to a third party solely for
         Enterprise Use; (ii) Entrust is identified as the source of the Client
         Software; and (iii) the Client Software is licensed to third parties
         pursuant to the terms and conditions of the shrink wrap license
         agreement embedded in or included with the Client Software. Each copy
         of Client Software provided to a third party pursuant to this
         distribution right shall count as a copy of Client Software granted or
         licensed to Enterprise herein. The maximum number of copies of Client
         Software for distribution by Enterprise for Enterprise Use is limited
         to those copies acquired by Enterprise under this Agreement for such
         use.

(c)      CERTIFICATE LICENSES, USER IDENTITIES AND DISTRIBUTION RIGHT
         FOR ENTERPRISE USE. Subject to the terms and conditions of this
         Agreement, Entrust grants to Enterprise a non-exclusive,
         non-transferable license to use the number of Certificate Licenses and
         User Identities licensed herein to Enterprise for Enterprise Use. A
         User Identity or Certificate License may not be assigned to more than
         one user, server or network node. Once a User Identity or Certificate
         License has been issued it may not be altered or re-deployed. Customer
         may license and distribute Certificate Licenses and User Identities to
         third parties solely for Enterprise Use. The maximum number of User
         Identities and Certificate Licenses for licensing and distribution by
         Customer for Enterprise Use is limited to those acquired by Customer
         under this Agreement for such use. The User Identities and Certificates
         Licenses licensed or distributed to third parties shall not contain any
         trademarks, tradenames, logos or any other designations of Entrust. All
         User Identities and Certificate Licenses distributed for Enterprise Use
         must be issued by Enterprise. Certificate Licenses must be time
         limited. A Certificate License which expires may not be renewed,
         instead, a new Certificate License must be issued. Each User Identity
         or Certificate License used or distributed shall count as one (1) User
         Identity or one (1) Certificate License granted or licensed herein.

(d)      INFRASTRUCTURE SOFTWARE LICENSES FOR CA SERVICES. Subject to the terms
         and conditions of this Agreement, Entrust hereby grants to Customer and
         Customer accepts a non-exclusive, non-transferable, internal license to
         use and copy the Infrastructure Software to the extent of the number of
         copies of Infrastructure Software licensed to Customer and to the
         extent of the number of User Identities and Certificate Licenses set by
         the Licensing String(s) delivered to Customer with or for that copy of
         Infrastructure Software to provide CA Services to CA Services
         Subscribers and CA Services Subscriber Users. If the number of
         permitted User Identities or Certificate Licenses for a copy of
         Infrastructure Software is not controlled using a Licensing String,
         Customer shall use such copy of Infrastructure Software to the extent
         of the number of User Identities and Certificate Licenses permitted for
         use with such copy of Infrastructure Software pursuant to this
         Agreement. The maximum number of copies of Infrastructure Software for
         use by Customer for the provision of CA Services is limited to those
         acquired by Customer pursuant to this Agreement for such use. Customer
         shall only use Licensing Strings provided by Entrust and only in
         conjunction with the copy of Infrastructure Software for which such
         Licensing Strings were delivered. Customer shall not copy or alter a
         Licensing String and may not provide the Infrastructure Software to any
         CA Services Subscribers or any CA Services Subscriber Users.

(e)      RIGHT TO DISTRIBUTE CA SERVICES SOFTWARE FOR CA SERVICES. Subject to
         the terms and conditions of this Agreement, Entrust grants to Customer
         a non-exclusive, non-transferable license to distribute CA Services
         Software to (i) CA Services Subscribers solely for use with the CA
         Services provided by Customer to such CA Services Subscribers, (ii) CA
         Services Subscriber Users solely for use with the CA Services provided
         by Customer to such CA Services Subscriber Users, and (iii) CA Services
         Subscribers for re-distribution by such CA Services Subscribers to CA
         Services Subscriber Users solely for use with the CA Services provided
         by Customer to such CA Services Subscriber Users. Such distribution
         rights are granted to Customer and CA Services Subscribers provided
         that; (i) Entrust is identified as the source of the CA Services
         Software, (ii) the CA Services Software is licensed to CA Services
         Subscribers and CA Services Subscriber Users pursuant to the terms and
         conditions of the shrink wrap license agreement embedded in or included
         with the CA Services Software. Customer shall give notice to CA
         Services Subscribers, prior to delivery, that the CA Services Software
         is for use only in conjunction with the CA Services. The maximum number
         of copies of CA Services Software for distribution by Customer for CA
         Services is limited to those acquired by Customer under this Agreement
         for such use. In the case of CA Services Software that is subject to a
         Restricted Use License (as described in Section 2(j)), Customer shall
         give notice of such restriction, prior to delivery, to each (i) CA

U.S. CASP 5.4                             3
October 24, 2000
<PAGE>   4

         Services Subscriber, and (ii) CA Services Subscriber User, of the
         applicable restrictions. Each copy of CA Services Software distributed
         by Customer to (i) a CA Services Subscriber, or (ii) a CA Services
         Subscriber User, shall count as one (1) copy of CA Services Software
         licensed hereunder. Each copy of CA Services Software distributed to a
         CA Services Subscriber for further re-distribution to a CA Services
         Subscriber User shall count as one (1) copy of CA Services Software
         licensed hereunder.

(f)      RIGHT TO DISTRIBUTE CERTIFICATE LICENSES AND USER IDENTITIES FOR CA
         SERVICES. Subject to the terms and conditions of this Agreement,
         Entrust grants to Customer a non-exclusive, non-transferable license to
         license and distribute Certificate Licenses and User Identities to (i)
         CA Services Subscribers, solely for use with the CA Services provided
         by Customer to such CA Services Subscribers, (ii) CA Services
         Subscriber Users, solely for use with the CA Services provided by
         Customer to such CA Services Subscriber Users, and (iii) CA Services
         Subscribers for re-distribution by such CA Services Subscribers to CA
         Services Subscriber Users solely for use with the CA Services provided
         by Customer to such CA Services Subscriber Users. The maximum number of
         User Identities and Certificate Licenses for licensing and distribution
         by Customer for CA Services is limited to those acquired by Customer
         under this Agreement for such use. Each User Identity or Certificate
         License distributed by Customer to (i) a CA Services Subscriber, or
         (ii) a CA Services Subscriber User, shall count as one (1) User
         Identity or one (1) Certificate License issued hereunder. A User
         Identity or Certificate License licensed and/or distributed by Customer
         for CA Services may not be assigned to more than one (1) user, server,
         or network node. If any User Identity or Certificate License used in
         the provision of the CA Services is subject to a Restricted Use License
         (as described in Section 2(j)), Customer shall provide notice of such
         restriction, prior to delivery, to each CA Services Subscriber and/or
         CA Services Subscriber User, as the case may be. The User Identities
         and Certificates licenses licensed and/or distributed to CA Services
         Subscribers and/or CA Services Subscriber Users shall not contain any
         trademarks, tradenames, logos, or any other designations of Entrust.
         Each User Identity or Certificate License deployed to a CA Services
         Subscriber for further redistribution to a CA Services Subscriber User
         shall count as one (1) User Identity or one (1) Certificate License
         issued hereunder. All User Identities and Certificate Licenses to be
         used for the CA Services must be issued by Customer. Customer shall be
         entitled to use Certificate Licenses and User Identities as required by
         a copy of Infrastructure Software to enable the operation of such copy
         of Infrastructure Software within any Certificate Authorities that
         Customer is entitled, pursuant to this Agreement, to operate for the
         provision of CA Services.

(g)      RESTRICTIONS ON PROVISION OF CA SERVICES. In no event shall Customer
         provide CA Services in Japan, except Customer may distribute CA
         Services Software in Japan to employees of a non-Japanese CA Services
         Subscribers whose global corporate headquarters are not located in
         Japan.

(h)      ENTRUST/TOOLKIT LICENSES. Subject to the terms and conditions of this
         Agreement, Entrust hereby grants and Customer accepts a non-exclusive,
         non-transferable, internal license to use and make copies of each
         Entrust/Toolkit for the purpose of developing Entrust-Ready
         Applications that are to be used with the Software. Entrust licenses to
         the Customer the non-exclusive right to use and make multiple copies of
         any Entrust APIs incorporated into Entrust-Ready Applications by way of
         an Entrust/Toolkit. Customer shall not otherwise sell, license,
         distribute or in any other manner commercially exploit any part of an
         Entrust/Toolkit (including the Entrust Engines). Customer shall not
         modify or distribute any part of an Entrust Engine, or any parts
         thereof. Any attempt to use information received as a part of an
         Entrust/Toolkit for any other purpose including, but not limited to,
         creation of an emulator of an item of Software constitutes a material
         breach of this Agreement.

(i)      OTHER SOFTWARE LICENSES. For all Software for which licensing terms are
         not provided elsewhere in this Section 2, subject to the terms and
         conditions of this Agreement, Entrust hereby grants to the Enterprise
         and the Enterprise accepts a non-exclusive, non-transferable, internal
         license (i) to make the number of copies of such Software as licensed
         herein, and (ii) to use each copy of such Software as set forth in its
         documentation. Entrust/Access software is a third party product and if
         Enterprise has acquired a license to such software pursuant to this
         Agreement, the terms of such license shall be those terms and
         conditions contained in the shrink wrap license accompanying or
         embedded in such software.

(j)      PROVISIONS COVERING ALL SOFTWARE. Enterprise does not acquire any
         rights, express or implied, in the Software, other than those rights
         specified in this Agreement. Enterprise may make additional copies of
         each item of Software, but only for back-up or archival reasons. Each
         permitted copy of all or part of an item of Software must include all
         copyright notices, restricted rights legends, proprietary markings and
         the like exactly as they appear on the copy delivered by Entrust to
         Enterprise. Enterprise may not host, time-share, rent, lease, sell,
         license, sublicense, assign, distribute or otherwise transfer an item
         of Software, except as provided in this Agreement. The Software and all
         modifications, enhancements and derivative works thereof, including all
         right, title and interest (and all intellectual proprietary rights
         therein) remain the sole and exclusive property of

U.S. CASP 5.4                             4
October 24, 2000

<PAGE>   5

         Entrust and/or its third-party licensors. Any third party software
         included with the Software may be used only with the Software unless
         otherwise authorized in writing by Entrust. If third party software is
         subject to a separate license agreement, then such separate agreement
         shall apply to Enterprise's use of the third party software. Enterprise
         shall not copy, modify, adapt or merge copies of the Software except as
         provided in this Agreement. Enterprise shall not translate, reverse
         engineer, de-compile or disassemble the Software except to the extent
         that law explicitly prohibits this restriction notwithstanding a
         contractual restriction to the contrary. If Enterprise obtains User
         Identities under this Agreement that (i) have been bundled together
         with Client Software or CA Services Software, or (ii) are authorized
         for use with a specific number of Applications (in the case of a single
         Application, referred to as a Single Application Bundle (SAB)), such
         User Identities shall be restricted for use only with the Client
         Software or CA Services Software with which such User Identities were
         bundled or with the number of Applications for which such User
         Identities were authorized ("RESTRICTED USE LICENSE").

3.       SUPPORT AND SERVICES

(a)      SUPPORT. Entrust shall provide Support to Customer in accordance with
         the terms and conditions set forth in Schedule B. The fees for Support
         to be provided by Entrust to Customer are set forth in Schedule A.
         Customer shall provide CA Services Subscribers and CA Services
         Subscriber Users with support services.

(b)      SERVICES. Upon Customer's request, Entrust will provide Services to
         Enterprise pursuant to a mutually agreed upon Statement of Work
         ("SOW").

4.       PRICE AND PAYMENT

(a)      PRICE. The fees for Software and Support are set forth in Schedule A.
         Unless otherwise stated, all fees excludes applicable federal, state,
         provincial, use, value-added and local taxes (excluding taxes based
         upon Entrust's net income) and the costs relating to the delivery of
         the Software. Customer shall pay to Entrust the amount of any such tax
         or additional costs.

(b)      PAYMENT. Unless otherwise stated in Schedule A, all Software fees are
         payable on delivery and all Support fees are payable annually, in
         advance. All amounts payable under this Agreement shall be paid by the
         Customer to the invoicing Affiliate of Entrust within thirty (30) days
         of the date of invoice. Unpaid invoices more than thirty (30) days
         overdue may be subject to an interest charge of one percent (1%) per
         month or the maximum rate legally permitted, whichever is less.

5.       ORDERS AND DELIVERY

(a)      SOFTWARE ORDERS. Customer shall be entitled to order Software, User
         Identities and Certificate Licenses pursuant to a purchase order
         document accepted by Entrust. Such Software, User Identities and
         Certificate Licenses shall be deemed delivered pursuant to terms of
         this Agreement. A purchase order shall be in writing and identify the
         Software being ordered, the quantity of User Identities or Certificate
         Licenses required (if applicable) and the shipping and invoicing
         locations. Upon receipt of a new Licensing String, the Customer shall
         stop using and destroy the previous Licensing String for the Software.
         All terms and conditions on a purchase order document shall be of no
         contractual effect between the parties.

(b)      DELIVERY. Entrust or one of its Affiliates shall deliver Customer's
         order, F.O.B. shipping point, to a location specified by the Customer
         within thirty (30) days of receipt of such order, subject to the
         receipt of all required documentation, including any required export
         and import permits. Thereafter, Customer shall be responsible for and
         bear all expenses (including taxes) related to making the permitted
         number of copies and distributing such copies as permitted in this
         Agreement. Customer will be the importer of record for the Software.

6.       SOFTWARE WARRANTY

(a)      SOFTWARE WARRANTY. Entrust warrants that (i) for a period of ninety
         (90) days from the date of delivery, each item of Software will perform
         in substantial accordance with the documentation delivered with such
         Software, and (ii) at the time of delivery, Entrust shall have used
         commercially reasonable efforts to cause the Software to be free of any
         known computer virus or harmful, malicious, or hidden program, data, or
         other computer instructions whose purpose is to disrupt, damage, or
         interfere with the use of computer and telecommunications software or
         hardware for their normal purposes.

(b)      EXCEPTIONS TO WARRANTY. Notwithstanding the foregoing, Entrust shall
         have no obligation to fix errors in the Software caused by accident,
         misuse, abuse, improper operation, misapplication, or any other cause
         external to the Software, or if such repair service would constitute an
         excluded service pursuant to the Support provisions.

(c)      REMEDY FOR BREACH OF WARRANTY. Except as specifically stated herein,
         Entrust's sole liability and the Enterprise's sole and exclusive remedy
         for breach of the provisions of this warranty section shall be, at
         Entrust's option, to (i) repair or replace the Software which does not
         meet Entrust's warranty and which is returned to Entrust, or (ii) take
         return of the Software and refund the price paid for the Software.

U.S. CASP 5.4                             5
October 24, 2000

<PAGE>   6

7.       INTELLECTUAL PROPERTY

(a)      INTELLECTUAL PROPERTY INDEMNITY. Entrust shall defend Customer from any
         claims by third parties that the Software furnished and used within the
         scope of this Agreement infringes upon or misappropriates a Canadian,
         United States or European patent, trademark, copyright, trade secret or
         other proprietary right (a "Claim"), and will pay any damages,
         settlements, costs, and expenses, including without limitation court
         costs and reasonable attorney's fees, finally awarded against Customer
         by a court or arbitrator in any proceeding related to such Claim,
         provided, however, that the Customer (i) gives to Entrust prompt
         written notice of each Claim threatened or received by the Customer,
         (ii) gives to Entrust the sole right to control and direct the
         investigation, defense and settlement of such Claim, and (iii) has not
         compromised or settled the Claim.

(b)      MITIGATION BY ENTRUST. If (i) Entrust becomes aware of an actual or
         potential Claim, or (ii) Customer provides Entrust with notice of an
         actual or potential Claim, Entrust may (or in the case of an injunction
         against Customer, shall), at Entrust's sole option and expense:

         (i)      procure for the Customer the right to continue to use the
                  affected portion of the Software;

         (ii)     modify or replace the affected portion of the Software with
                  functionally equivalent or superior software so that
                  Customer's use is non-infringing; or

         (iii)    if (i) or (ii) are not commercially reasonable, take return of
                  the affected portion of the Software and pay to Customer the
                  cost of the affected portion of the Software depreciated over
                  a three (3) year period from the date of acquisition on a
                  straight line basis less any outstanding moneys owed on such
                  affected portion of the Software.

(c)      EXCEPTIONS TO INDEMNITY. Entrust shall have no liability, and shall be
         indemnified and held harmless by the Customer against any Claim in
         respect of any Software if:

         (i)      such Software is used by the Enterprise outside the scope or
                  the license granted in this Agreement or in a manner or for a
                  purpose other than that for which it was supplied, as
                  contemplated by Entrust's documentation;

         (ii)     such Software is modified by the Enterprise without the
                  written consent of Entrust;

         (iii)    such Software is used by the Enterprise in combination with
                  other software not provided by Entrust and the infringement
                  arises from such combination or the use thereof; or

         (iv)     the Claim relates to the use of any version of the Software
                  other than the current, unaltered release, if such Claim would
                  have been avoided by the use of a current unaltered release of
                  the Software.

(d)      LIMIT TO INDEMNITY. THE PROVISIONS OF THIS ARTICLE 7 STATE THE SOLE AND
         EXCLUSIVE LIABILITY OF ENTRUST, AND THE SOLE AND EXCLUSIVE REMEDY OF
         ENTERPRISE WITH RESPECT TO ANY CLAIM OF THE NATURE DESCRIBED HEREIN.
         ENTRUST'S TOTAL CUMULATIVE LIABILITY TO ENTERPRISE FOR ANY CLAIM OR
         INDEMNITY UNDER THIS ARTICLE 7 SHALL NOT EXCEED ONE MILLION
         ($1,000,000.00) U.S. DOLLARS.

8.       LIMITATION OF LIABILITY

(a)      NO OTHER WARRANTIES OR REMEDIES. EXCEPT AS SPECIFICALLY PROVIDED IN
         THIS AGREEMENT, ENTRUST DISCLAIMS ALL OTHER REPRESENTATIONS, WARRANTIES
         AND CONDITIONS, EITHER EXPRESS, IMPLIED, STATUTORY, BY USAGE OF TRADE
         OR OTHERWISE INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTIES OF
         MERCHANTABILITY, NON-INFRINGEMENT, TITLE, SATISFACTORY QUALITY OR
         FITNESS FOR A PARTICULAR PURPOSE.

(b)      LIMITATION OF LIABILITY. IN NO EVENT SHALL ENTRUST OR ENTERPRISE
         (INCLUDING SUCH PARTY'S AFFILIATES, SUBCONTRACTORS, AGENTS, SUPPLIERS,
         DIRECTORS OR EMPLOYEES) BE LIABLE FOR ANY SPECIAL, INCIDENTAL,
         PUNITIVE, EXEMPLARY, INDIRECT, RELIANCE OR CONSEQUENTIAL DAMAGES
         (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS, LOSS OF
         PROFITS, BUSINESS INTERRUPTION, LOSS OF DATA, LOST SAVINGS OR OTHER
         SIMILAR PECUNIARY LOSS) WHETHER ARISING FROM CONTRACT (INCLUDING
         FUNDAMENTAL BREACH), TORT (INCLUDING NEGLIGENCE) OR ANY OTHER THEORY OF
         LIABILITY. EXCEPT ENTRUST'S INDEMNITY OBLIGATIONS IN SECTION 7, IN NO
         EVENT SHALL ENTRUST'S TOTAL CUMULATIVE LIABILITY PURSUANT TO THIS
         AGREEMENT EXCEED THE LICENSE FEES PAID BY CUSTOMER TO ENTRUST HEREIN.

U.S. CASP 5.4                             6
October 24, 2000
<PAGE>   7

(c)      NOTWITHSTANDING THE FOREGOING, NO LIMITATION OF EITHER PARTY'S
         LIABILITY SET FORTH IN THIS AGREEMENT SHALL APPLY TO (I) DAMAGES
         ARISING FROM A PARTY'S BREACH OF ITS CONFIDENTIALITY OBLIGATIONS, (II)
         DAMAGES ARISING FROM A PARTY'S INFRINGEMENT OF THE OTHER PARTY'S
         INTELLECTUAL PROPERTY RIGHTS, OR (III) CLAIMS FOR INJURY TO INDIVIDUALS
         OR DAMAGE TO TANGIBLE PROPERTY CAUSED BY THE NEGLIGENCE OF SUCH PARTY
         OR ITS EMPLOYEES, SUBCONTRACTORS OR AGENTS.

9.       CONFIDENTIALITY

(a)      TREATMENT OF CONFIDENTIAL INFORMATION. Enterprise acknowledges that the
         Software (and any information incorporated therein or related thereto)
         is the Confidential Information of Entrust. Enterprise shall not
         disclose the results of any benchmark tests of the Software to any
         third party without the prior written approval of Entrust. Each party
         (including its Affiliates) shall retain the Confidential Information of
         the other party (including its Affiliates) in confidence and shall use
         and disclose it solely for the purpose of, and in accordance with, this
         Agreement. Each party (including its Affiliates) shall only disclose
         Confidential Information of the other party (or any of its Affiliates)
         to those of its employees with a need to know such Confidential
         Information. Each party (including its Affiliates) shall use the same
         degree of care as it uses to protect its own confidential information
         of a similar nature, but no less than reasonable care, to prevent the
         unauthorized use or disclosure of the other party's (or any of its
         Affiliates) Confidential Information.

         Neither party (or any of its Affiliates) shall be bound by any
         obligations restricting disclosure and use set forth in this Agreement
         with respect to Confidential Information of the other party (or any of
         its Affiliates), or any part thereof, which:

         (i)      was known to the receiving party (or any of its Affiliates)
                  prior to disclosure;

         (ii)     was lawfully in the public domain prior to its disclosure, or
                  becomes publicly available other than through a breach of this
                  Agreement;

         (iii)    was disclosed to the receiving party (or any of its
                  Affiliates) by a third party, provided that such third party
                  is not in breach of any confidentiality obligation in respect
                  of such information; or

         (iv)     is independently developed by the receiving party (or any of
                  its Affiliates).

(b)      If the receiving party (or any of its Affiliates) is compelled pursuant
         to legal, judicial, or administrative proceedings, or otherwise
         required by law, to disclose Confidential Information of the disclosing
         party (or any of its Affiliates), the receiving party (or, if
         applicable, its Affiliates) shall use reasonable efforts to (i) seek
         confidential treatment for such Confidential Information, and (ii)
         provide prior notice to the disclosing party (or, if applicable, its
         Affiliates) to allow the disclosing party (or, if applicable, its
         Affiliates) to seek protective or other court orders.

10.      TERM AND TERMINATION

(a)      TERM. This Agreement shall commence on the Effective Date and shall
         continue in effect unless terminated as set out herein.

(b)      TERMINATION BY ENTRUST. Entrust may terminate this Agreement with
         notice if the Customer:

         (i)      assigns or attempts to assign this Agreement or any of the
                  Customer's rights hereunder to a third party except in
                  accordance with Section 11(h);

         (ii)     fails to correct a material breach of its obligations to
                  Entrust within thirty (30) days after written notification
                  from Entrust of such material breach;

         (iii)    files a bankruptcy petition or has such a petition filed
                  involuntarily against it, becomes insolvent, makes an
                  assignment for the benefit of creditors, consents to the
                  appointment of a trustee, or if bankruptcy reorganization or
                  insolvency proceedings are instituted by or against the
                  Customer.

(c)      TERMINATION BY CUSTOMER. Customer may terminate this Agreement with
         notice if Entrust:

         (i)      assigns or attempts to assign this Agreement or any of
                  Entrust's obligations hereunder to a third party except in
                  accordance with Section 11(h);

         (ii)     fails to correct a material breach of its obligations to
                  Customer within thirty (30) days after written notification
                  from the Customer of such material breach; or

         (iii)    files a bankruptcy petition or has such a petition filed
                  voluntarily against it, becomes insolvent, makes an assignment
                  for the benefit of creditors, consents to the appointment of a
                  trustee, or if bankruptcy, reorganization or insolvency
                  proceedings are instituted by or against Entrust.

U.S. CASP 5.4                             7
October 24, 2000

<PAGE>   8

(d)      EFFECTS OF TERMINATION. In the event of such termination by Entrust,
         the Customer shall destroy or return immediately the Software and all
         copies thereof to Entrust. In the event of such termination by
         Customer, Customer shall be entitled to use the Software licensed prior
         to the date of termination provided that Customer complies with the
         terms of this Agreement in respect to the use of such Software.

(e)      SURVIVAL. In addition to this Section, Sections 1, 6, 7, 8, 9 and 11
         shall survive any termination or expiration of this Agreement. All
         payment obligations shall survive any termination or expiration of this
         Agreement.

11.      GENERAL

(a)      AUDIT RIGHTS. The Customer shall keep reasonable records relating to
         (i) the number of copies of Software made, used or distributed by
         Enterprise; and (ii) the number of User Identities and Certificate
         Licenses issued, used or distributed by Enterprise. A chartered or
         certified public accountant selected by Entrust may, upon reasonable
         notice and during normal business hours, but no more often than once a
         year, inspect the records of the Customer.

(b)      U.S. GOVERNMENT END-USERS. The Software is a "commercial item" as that
         term is defined at 48 C.F.R. 2.101 (JAN 1998), consisting of
         "commercial computer software" and "commercial computer software
         documentation" as such terms are used in 48 C.F.R. 12.212 (SEPT 1995),
         and is provided to the U.S. Government only as a commercial end item.
         Government end users acquire the rights set out in this Agreement for
         the Software consistent with: (i) for acquisition by or on behalf of
         civilian agencies, the terms set forth in 48 C.F.R. 12.212 (SEPT 1995);
         or (ii) for acquisition by or on behalf of units of the Department of
         Defense, the terms set forth in 48 C.F.R. 227.7202.

(c)      EXPORT RESTRICTIONS. The Software and related information is subject to
         export and import restrictions. Customer shall comply with any laws
         which may impact Customer's right to export, import or use the Software
         or related information (including, without limitation, United States
         and Canadian export laws). Customer shall not use the Software or
         related information for any purposes prohibited by export laws,
         including, without limitation, nuclear, chemical or biological weapons
         proliferation. Customer shall be responsible for procuring all required
         permissions for any subsequent export, import or use of the Software or
         related information.

(d)      INCLUSION OF AFFILIATES. Each party warrants that it has the authority
         to bind its Affiliates to the provisions of this Agreement. Entrust may
         use one or more Affiliates to perform its obligations under this
         Agreement, provided that such use will not affect Entrust's obligations
         hereunder. Customer may extend the rights designated for Affiliates
         under this Agreement to its Affiliates, provided that any such
         Affiliates agree to comply with the obligations, and otherwise be
         subject to the terms and conditions, of this Agreement and that
         Customer shall cause each such Affiliate to comply with the terms and
         conditions of this Agreement to the full extent as if the Affiliate
         were a party hereto, and that any act or omission relating to this
         Agreement (including without limitation a breach hereof) by such
         Affiliate shall constitute an act or omission of Customer.

(e)      NOTICE. Any notice to be given hereunder shall be given in writing by
         prepaid receipted mail, facsimile, or overnight courier, and shall be
         effective as follows (i) in the case of facsimile or courier, on the
         next business day, and (ii) in the case of receipted mail, five (5)
         business days following the date of deposit in the mail.

(f)      FORCE MAJEURE. Neither party shall be deemed in default hereunder or
         liable for any loss or damage resulting from delays in performance or
         from failure to perform or comply with the terms of this Agreement due
         to any causes beyond its reasonable control, which causes include but
         are not limited to acts of God or the public enemy; riots and
         insurrections, war, accidents, fire, strikes and other labor
         difficulties (whether or not the party is in a position to concede to
         such demands), embargoes, judicial action, lack of or inability to
         obtain export permits or approvals, necessary labor, materials, energy,
         utilities, components or machinery, acts of civil or military
         authorities.

(g)      WAIVER. The failure of a party to claim a breach of any term of this
         Agreement shall not constitute a waiver of such breach or the right of
         such party to enforce any subsequent breach of such term.

(h)      ASSIGNMENT. Neither the Customer nor Entrust shall assign this
         Agreement, any interest herein or any rights hereunder without the
         prior written consent of the other party, except that:

         (i)      the Customer may assign this Agreement to any party which
                  acquires all or substantially all of its related business by
                  merger, sale of assets, or otherwise or to an Affiliate of
                  Customer; and

         (ii)     Entrust may assign this Agreement to any party which acquires
                  all or substantially all of its related business by merger,
                  sale of assets, or otherwise or to an Affiliate of Entrust.

(i)      SEVERABILITY. In the event that any provision of this Agreement is
         found to be invalid, void or

U.S. CASP 5.4                             8
October 24, 2000

<PAGE>   9

         unenforceable, the parties agree that unless such provision materially
         affects the intent and purpose of this Agreement, such invalidity,
         voidability or unenforceability shall not affect the validity of this
         Agreement nor the remaining provisions herein.

(j)      THIRD PARTY BENEFICIARIES. Customer hereby acknowledges that there may
         be third party beneficiaries to this Agreement. To the extent that this
         Agreement contains provisions that relate to the use of Software in
         which such third parties have an interest, such provisions are made
         expressly for the benefit of such third party beneficiaries and are
         enforceable by such third-party beneficiaries in addition to being
         enforceable by Entrust.

(k)      GOVERNING LAW. This Agreement shall be governed by the laws of the
         State of Texas, U.S.A., without regard to its conflict of law
         principles. The jurisdiction for any legal action shall be exclusively
         a state or federal court in Dallas County, Texas, U.S.A. The
         application of the United Nations Convention on Contracts for the
         International Sale of Goods to this Agreement is expressly excluded.

(l)      ENTIRE AGREEMENT. This Agreement and the Schedules hereto constitute
         the entire agreement between the parties on the subject matter hereof
         and supersede all prior agreements, communications and understandings
         of any nature whatsoever, oral or written including any shrink wrap
         license included with the Software. This Agreement may not be modified
         or waived orally and may be modified only in a writing signed by a duly
         authorized representative of both parties.

IN WITNESS WHEREOF, the parties have signed this Agreement as of the Effective
Date.

ENTRUST TECHNOLOGIES INC.                          ZIXIT CORPORATION

By:    /s/ RICHARD D. SPURR                        By:    /s/ RONALD A. WOESSNER
   -------------------------------------                 ----------------------

Name:  Richard D. Spurr                            Name: Ronald A. Woessner
     -----------------------------------                 ----------------------

Title: Exec. V.P. Global Sales & Service           Title: S.V.P.
      ----------------------------------                 ----------------------

Date:  11/6/00                                     Date: 11/6/00
     -----------------------------------                -----------------------

U.S. CASP 5.4                             9
October 24, 2000<PAGE>   1
                                                                    EXHIBIT 10.1

                                 AMENDMENT NO. 1
                                       TO
                           PURCHASE AND SALE AGREEMENT

         THIS AMENDMENT NO. 1 TO PURCHASE AND SALE AGREEMENT (this "Amendment")
dated September 25, 2000, is made by and between III Exploration Company, an
Idaho corporation ("Seller"), and Petroglyph Energy, Inc., a Delaware
corporation ("Buyer").

                                  WITNESSETH:

         WHEREAS, pursuant to that certain Purchase and Sale Agreement dated
December 28, 1999 by and between Seller and Buyer, as supplemented by that
certain letter agreement dated February 18, 2000 (collectively, the
"Agreement"), Seller sold, assigned and conveyed to Buyer, and Buyer purchased
and accepted, certain oil and gas properties and related assets located in the
States of Utah, Colorado and Wyoming;

         WHEREAS, Seller and Buyer desire to amend the Agreement to accurately
reflect the oil and gas properties actually conveyed to Buyer; and

         WHEREAS, Seller and Buyer deem it in their mutual best interests to
execute and deliver this Amendment.

         NOW, THEREFORE, in consideration of the foregoing recitals and the
mutual covenants and agreements contained herein, Seller and Buyer do hereby
agree as follows:

1.       Amendment to Property Exhibits. Exhibit II to the Agreement is amended
         and restated in its entirety as set forth on Exhibit II to this
         Amendment.

2.       Purchase Price Adjustment. In consideration for the amendment of
         Exhibit II to the Agreement, Seller shall pay to Buyer the sum of
         $402,909.85 in immediately available funds by wire transfer to a bank
         account designated by Buyer.

3.       Defined Terms. Capitalized terms used in this Amendment and not
         otherwise defined shall have the respective meanings assigned to such
         terms in the Agreement.

4.       Counterparts. This Amendment may be executed in counterparts, all of
         which are identical and all of which constitute one and the same
         instrument. It shall not be necessary for Buyer and Seller to sign the
         same counterpart.

5.       No Further Modification. Except as expressly modified hereby, all of
         the representations, warranties, terms, covenants, conditions and other
         provisions of the Agreement shall remain in full force and effect in
         accordance with their respective terms.

                                      -1-

<PAGE>   2

         IN WITNESS WHEREOF, this Agreement is executed by the parties hereto on
the date set forth above.

                                            SELLER:

                                            III EXPLORATION COMPANY

                                            By: /s/ William C. Glynn
                                                ---------------------
                                                William C. Glynn
                                                President

                                            BUYER:

                                            PETROGLYPH ENERGY, INC.

                                            By: /s/ Robert C. Murdock
                                                ---------------------
                                                Robert C. Murdock
                                                President

                                      -2-

<PAGE>   3

                                   EXHIBIT II

<TABLE>
<CAPTION>
               WELL NAME                       STATE         OPERATOR
               ---------                       -----         --------
<S>       <C>                                  <C>          <C>

   1      Wilkin Ridge 13-23                     ?           Chandler

   2      E. Hunter Mesa 3-11                    CO          Chandler

   3      Antelope Draw #2-17-4C                 UT          Chandler

   4      Antelope Draw #3-17-3C                 UT          Chandler

   5      Desert Springs 16-19-10-1              UT          Chandler

   6      Desert Springs 3-29-10-18              UT          Chandler

   7      Desert Springs Fed 20-1                UT          Chandler

   8      E Coyote Fed 14-4-8-25                 UT          Chandler

   9      Fed 14-4                               UT          Chandler

   10     Flu Knolls Fed 23-3                    UT          Chandler

   11     Glen Bench 2-36                        UT          Chandler

   12     Glen Bench 8-19                        UT          Chandler

   13     Glen Bench Federal #13-20              UT          Chandler

   14     Glen Bench Federal #31-20              UT          Chandler

   15     Glen Bench Federal #31-30              UT          Chandler

   16     Glen Bench State #6-16                 UT          Chandler

   17     Glen Bench State 6-36-8-21             UT          Chandler

   18     Glen Bench State 8A-36-8-21            UT          Chandler

   19     Glen Bench Unit 11-16-8-22             UT          Chandler

   20     Glen Bench Unit 12-36                  UT          Chandler

   21     Glen Bench Unit 15-19-8-22             UT          Chandler

   22     Sage Grouse Fed 6-14                   UT          Chandler

   23     UTD Walton 26-03                       UT          Chandler

   24     W. River Bend 16-17-10-1               UT          Chandler

   25     W. River Bend 3-12-10-15               UT          Chandler

   26     White River Unit 13-35-8-22            UT          Chandler

   27     White River Unit 15-35-8-22            UT          Chandler

   28     WRU #16-9                              UT          Chandler
</TABLE>

                                      -3-

<PAGE>   4

<TABLE>
<CAPTION>
               WELL NAME                       STATE         OPERATOR
               ---------                       -----         --------
<S>       <C>                                  <C>          <C>
   29     WRU #31-4                              UT          Chandler

   30     WRU #43-16                             UT          Chandler

   31     WRU #45-16                             UT          Chandler

   32     Tribal 36-53                           UT           Coastal

   33     Duncan Fed 33-09                       UT       Coastal/Conoco

   34     Fed 35-05                              UT       Coastal/Conoco

   35     Tribal 36-17                           UT       Coastal/Conoco

   36     Stage Coach 14-34                      UT            Enron

   37     Stage Coach 19-33                      UT            Enron
</TABLE>

                                      -4-

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00017-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00017-of-00352.parquet"}]]