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                                                                    EXHIBIT 10.1

                  FOURTH AMENDMENT TO THE HARBINGER CORPORATION

                             1996 STOCK OPTION PLAN



         THIS FOURTH AMENDMENT TO THE HARBINGER CORPORATION 1996 STOCK OPTION
PLAN (the "Amendment") is made effective as of the _____ day of May, 1999 (the
"Effective Date"), by HARBINGER CORPORATION, a corporation organized and doing
business under the laws of the State of Georgia (the "Company"). All capitalized
terms in this Amendment have the meaning ascribed to such term as in the
Harbinger Corporation 1996 Stock Option Plan (the "Plan"), unless otherwise
stated herein.

                              W I T N E S S E T H:

         WHEREAS, the First Amendment to the Plan was approved by the
shareholders of the Company at the 1997 Annual Meeting
of Shareholders;

         WHEREAS, the Second Amendment to the Plan was approved by the
shareholders of the Company at the Special Meeting of Shareholders held on
December 18, 1997;

         WHEREAS, the Third Amendment to the Plan was approved by the
shareholders of the Company at the 1998 Annual Meeting of Shareholders; and

         WHEREAS, the Board of Directors of the Company desires to amend the
Plan to add certain provisions to insure compliance with the safe harbor
provisions of Section 162(m) of the Internal Revenue Code of 1986, as amended,
and the regulations promulgated thereunder;

         NOW, THEREFORE, in consideration of the premises and mutual promises
contained herein, the Plan is hereby amended as follows:

         SECTION 1. Section 3.1 of the Plan is hereby amended by deleting the
first sentence of Section 3.1 of the Plan in its entirety and substituting in
lieu thereof the following:

                           "3.1 Shares Reserved for Issuance. Subject to any
                  antidilution adjustment pursuant to Section 3.2, the maximum
                  number of Shares that may be subject to Options granted
                  hereunder shall not exceed 8,737,500, plus the number of Prior
                  Plan Shares; provided, however, the maximum number of Shares
                  with respect to which Options may be granted to any individual
                  grantee in any calendar year shall be 1,000,000."

         SECTION 2. Section 5 of the Plan is hereby amended by deleting the
first sentence of Section 2 in its entirety and substituting in lieu thereof the
following:

                           "This Plan shall be administered by the Committee,
                  which shall consist of three (3) or more directors appointed
                  by the Board, each of whom is an "outside director" within the
                  meaning of Section 162(m) of the Code and is not while a
                  member of the Committee, or was not during the one (1) year
                  prior to serving as a member of the Committee, eligible to
                  receive equity securities of the Company, or any affiliate of
                  the Company, pursuant to this Plan, the Prior Plan, or any
                  other plan of the Company or any affiliate of the Company,
                  except as may be permitted under Section 16(b)(3) of the
                  Exchange Act."

         SECTION 3. Except as specifically amended by this Fourth Amendment, the
Plan shall remain in full force and effect as prior to this Fourth Amendment.

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         IN WITNESS WHEREOF, the Company has caused this FOURTH AMENDMENT TO THE
HARBINGER CORPORATION 1996 STOCK OPTION PLAN to be executed on the Effective
Date.


                                      HARBINGER CORPORATION


                                      By:
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ATTEST:


By:
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