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                                   EXHIBIT 99A
                              EMPLOYMENT AGREEMENT
















                                   FORM 10-Q
                                    PAGE 24
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                             CONTRACT OF EMPLOYMENT


The undersigned:

1.       HARBINGER CORPORATION, established in Atlanta, Georgia, USA (hereafter
         known as the "Company")


         and


2.       MR. WILLEM VAN NIEUWENHUYZEN residing in Zeist, The Netherlands
         (hereafter known as "Mr. van Nieuwenhuyzen" or the "Employee")

Declare Agreement as to the following:

1.       Function

         a.       The Company employs Mr. van Nieuwenhuyzen in the function of
                  General Manager, Europe and Africa. He reports to the Chief
                  Executive Officer, Harbinger Corporation.

         b.       Mr. van Nieuwenhuyzen binds himself to undertaking the
                  responsibilities reasonably demanded of him by the Company in
                  the function of General Manager, Europe and Africa. Mr. van
                  Nieuwenhuyzen places his entire energies at the disposal of
                  the Company.

         c.       Mr. van Nieuwenhuyzen will not undertake any supplemental
                  employment, paid or unpaid, without written permission from
                  the Company.

         d.       Mr. van Nieuwenhuyzen agrees to perform to the best of his
                  abilities all duties which may reasonably be assigned to him
                  by or on behalf of the Company and which are connected with
                  the Company's business, and to follow the directions which
                  shall be given by or on behalf of the Company.

         e.       Mr. van Nieuwenhuyzen's principal place of work is The
                  Netherlands, unless changed by the Company. Mr. van
                  Nieuwenhuyzen will travel throughout Europe and Africa.

2.       The Term of the Contract

         This Agreement has been entered into for an indefinite period of time,
         effective August 1, 1997 and starting October 1, 1997.


3.       Salary, Bonus and Stock Option

         Mr. van Nieuwenhuyzen's salary is Gldrs 30,770 per month. The salary
         will be paid in arrears by the Company prior to the end of each month
         into a bank account to be specified by Mr. van Nieuwenhuyzen.

         Moreover, Mr. van Nieuwenhuyzen is entitled to the annual holiday
         supplement, which is established at 8.33% of gross salary (Gldrs.
         30,700) and will be paid annually in the month of July, adjusted
         proportionately for actual length of service during a given year.

         Total annual salary is 12 times monthly salary plus annual holiday
         supplement, and excluding bonuses, commissions, incentives and other
         allowances.


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         The Company shall deduct and pay all the obligatory wage taxes and
         social insurance premiums according to Dutch law in respect of all
         amounts to be paid to Mr. van Nieuwenhuyzen under this Agreement;
         unless, in accordance with Dutch law and regulations, it results from
         this Agreement and from the nature of the payment to be made that it
         can be made untaxed and not subject to withholding.

         The employee cannot claim compensation for overwork.

         In addition to the Base Salary, Mr. van Nieuwenhuyzen will be eligible
         for participation in an incentive bonus program as established by the
         Company (subject to meeting targets, based on criteria to be determined
         by the Company at its sole discretion) with the bonus in the amount of
         40% of Base Salary plus annual holiday supplement upon achieving the
         targets. Such bonus is not guaranteed, but is subject to an
         accelerator/decelerator based on beating/missing the European and
         overall Company financial plan. It is expected that about 80% of this
         payment will be based on European performance and 20% on total Company
         performance, and may vary from year to year. For the first two quarters
         of employment, the bonus will be guaranteed and paid in arrears at
         40,000 Gldrs each quarter. Thereafter, bonus is not guaranteed and will
         be paid annually soon after the end of the Company's fiscal year end
         (December 31st).

         In addition to the Base Salary, Mr. van Nieuwenhuyzen will receive a
         stock option for 50,000 shares awarded under the Harbinger Corporation
         1996 Stock Option Plan ("Plan"). Shares underlying award vest evenly
         over 4 years. The option is awarded under the Plan approved by the
         Dutch tax authorities. Mr. van Nieuwenhuyzen will be liable for any tax
         liability from this award. The Company will loan Mr. van Nieuwenhuyzen
         up to 100,000 Gldrs to pay these taxes, for one year, at an interest
         rate of 9.0% after which principal and interest will be due and payable
         in full.

         Mr. van Nieuwenhuyzen will receive an expense allowance of Gldrs.
         10,000 per year.

4.       Company Car

         a.       In order to carry out his duties, the Company will place a
                  company car equal to a BMW 525 or equivalent at Mr. van
                  Nieuwenhuyzen's disposal, including petrol costs but excluding
                  VAT, on lease basis based on 30,000 km per year, with due
                  consideration of the clause below referring to private use.
                  The company car is provided pursuant to a separate company car
                  Agreement.

                  Mr. van Nieuwenhuyzen is authorized to use the company car for
                  reasonable private use including travel aboard. It is at the
                  discretion of the Company to decide what is understood by
                  reasonable private use.

         b.       When Mr. van Nieuwenhuyzen, for any reason, does not carry out
                  any duties for the Company for a period in excess of one
                  month, he is obliged to return the car to the Company.

         c.       Mr. van Nieuwenhuyzen acknowledges that the allowances and
                  private use of the car mentioned hereabove might give rise to
                  tax liability. The financial consequences of such liability
                  shall be borne by Mr. van Nieuwenhuyzen.

5.       Paid Leave

         a.       Each calendar year the employee is entitled to 25 days leave.
                  The dates will be fixed by the Company after consultation with
                  Mr. van Nieuwenhuyzen.

         b.       The company will not provide financial compensation for unused
                  days of leave.




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         c.       Upon termination of employment, Mr. van Nieuwenhuyzen will
                  receive compensation for the remaining days of leave.

         d.       If Mr. van Nieuwenhuyzen has taken too many days leave in
                  proportion to the term of employment, he will repay the
                  Company with an amount representing the excess days. This
                  amount can be deducted by the Company from the amount still
                  owing to Mr. van Nieuwenhuyzen.

6.       Incapacity to work due to illness

         a.       In the event that Mr. van Nieuwenhuyzen is unable to perform
                  his duties for reasons of illness, the Company will pay one
                  hundred percent (100%) of the Employee's last earned gross
                  Base Salary for a maximum period of four weeks. Thereafter the
                  Company will pay seventy (70%) of the Employee's last earned
                  gross Base Salary for a maximum period of 48 weeks.

         b.       The employee shall not be entitled to receive supplementary
                  payments 30% over the legal minimum of 70% of his salary
                  payments, if and to the extent that the employee shall have a
                  claim on a third party in connection with his disability to
                  work. Notwithstanding the foregoing, the Company may at its
                  sole discretion nevertheless decide to make these
                  supplementary payments by way of an advance on damages to be
                  received by the employee from such third party, subject to
                  assignment by the employee to the Company of that claim on a
                  third party for the amount of the advances made by the
                  Company.

7.       Duty to Maintain Secrecy

         a.       The Company may disclose to Employee certain Trade Secrets and
                  Confidential Information (defined below). Employee
                  acknowledges and agrees that the Trade Secrets and
                  Confidential Information are the sole and exclusive property
                  of the Company (or a third party providing such information to
                  the Company) and that the Company or such third party owns all
                  worldwide rights therein under patent, copyright, trade
                  secret, confidential information, or other property right.
                  Employee acknowledges and agrees that the disclosure of the
                  Trade Secrets and Confidential Information to Employee does
                  not confer upon Employee and license, interest or rights of
                  any kind in or to the Trade Secrets of Confidential
                  Information. Employee may use the Trade Secrets and
                  Confidential Information solely for the benefit of the Company
                  while Employee is employed or retained by the Company. Except
                  in the performance of services for the Company, Employee will
                  hold in confidence and not reproduce, distribute, transmit,
                  reverse engineer, decompile, disassemble, or transfer,
                  directly or indirectly, in any form, by any means, or for any
                  purpose, the Trade Secrets or the Confidential Information or
                  any portion thereof. Employee agrees to return tot he Company,
                  upon request by the Company, the Trade Secrets and
                  Confidential Information and all materials relating thereto.

         b.       Employee's obligations under this Agreement with regard to the
                  Trade Secrets shall remain in effect for as long as such
                  information shall remain a trade secret under applicable law.
                  Employee acknowledges that its obligations with regard to the
                  Confidential Information shall remain in effect while Employee
                  is employed or retained by the Company and for three (3) years
                  thereafter. As used herein, "Trade Secrets" means information
                  of the Company, its licensers, suppliers, customers, or
                  prospective licensers or customers, including, but not limited
                  to, technical or non-technical data, formulas, patterns,
                  compilations, programs, devices, methods, techniques,
                  drawings, processes, financial data, financial plans, product
                  plans, or a list of actual or potential customers or
                  suppliers, which (a) derives economic value, actual or
                  potential, from not being generally known to, and not being
                  readily ascertainable by proper means by, other persons who
                  can obtain economic value from its disclosure or user; and (b)
                  is the subject of efforts that are reasonable under the
                  circumstances to maintain its secrecy. As used herein,
                  "Confidential Information" means information, other than Trade
                  Secrets, that is of value to its owner and is 


                                   FORM 10-Q
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                  treated as confidential, including, but not limited to, future
                  business plans, licensing strategies, advertising campaigns,
                  information regarding executives and employees, and the terms
                  and conditions of this Agreement.

         c.       The employee must obtain written permission of the Company
                  before submission of any written material submitted for
                  publication, which have any relation to the Company or related
                  companies.

8.       Supplementary Occupational Disability

         The Company has arranged for a supplementary occupational disability
         insurance, which will provide coverage in case of disability
         (arbeidsongeschiktheid). The Company will pay 50% of the premium for
         such insurance. This coverage will pay the difference between 70% of
         the annual salary and the maximum payment by the state provided under
         the Disability Act (WAO), known as wage-privation
         (loondervingsuitkering). In many cases the state provided payment may
         decrease significantly over time or be lower, if the employee does not
         or no longer qualifies for this wage-privation payment. The difference
         between the wage-privation payment and the lower level (known as
         WAO-gat) will not be covered by the Company's disability plan. This
         coverage is not mandatory. The employee can make arrangements for such
         coverage at his own discretion.

         This insurance is subject to satisfying medical eligibility. The
         regulations of this insurance will be provided as a supplement to this
         contract.

9.       Health Insurance

         The Company shall provide Employee with enrollment in Company's Dutch
         medical plan subject to benefits and restrictions applicable to all
         Dutch employees of the Company

10.      Pension

         There are no pension contributions by the company to Mr. van
         Nieuwenhuyzen in his position.

11.      Non-competition

         Mr. van Nieuwenhuyzen will during a period of one year after
         termination of his employment abstain by way of employment or otherwise
         of exercising any activity, which may be considered to be competitive
         with that, activity carried out by Harbinger Corporation and/or an
         affiliated company. The restriction shall be valid in Europe and
         Africa.

         The Company may give permission in writing to allow Mr. van
         Nieuwenhuyzen to not be bound by some or all of the terms of this
         provision.

12.      Severance Payment

         In case of termination of this contract by the Company without cause,
         the company will continue salary payments to the employee for a minimum
         of three months after termination or one month per year, whichever is
         greater.

13.      Inventions

         The Company must immediately be informed of all inventions (patentable
         or not) made by the employee during his employment with the Company and
         the three years thereafter, independently or in connection with others,
         having any connection with the Company activities. All such invention
         becomes 


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         unconditional property of the Company. The duty of maintaining secrecy
         as described in Article 7 also applies in such cases.

         All designs, drawings, memoranda, notes, brochures and similar
         documents containing information concerning such inventions, or other
         confidential, financial or business information will be returned by the
         employee to the Company upon request.

         As far as it is necessary, the employee will cooperate with
         establishment of industrial property rights over the inventions as
         described in this article and make over such rights to the Company.

14.      Amendments

         Amendments to this contract of employment can only be agreed upon in
         written form.

15.      Applicable Law

         This Agreement will be governed by and shall be construed in accordance
         with the laws of The Netherlands. All conflicts shall be submitted to
         the competent court in The Netherlands. This Agreement cancels and
         replaces all past Agreements, understandings and all letters or
         documents exchanged between the parties, prior to the date of this
         Agreement.

HARBINGER CORPORATION               MR. VAN NIEUWENHUYZEN



/s/ David Leach                     /s/ Willem van Nieuwenhuyzen
----------------------              ----------------------------
By:                                 The Employee








                                   FORM 10-Q
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