Exhibit 4.22

                             TERMINATION AGREEMENT

Effective this 1st day of November, 2002.

BETWEEN:

                  MITEL KNOWLEDGE CORPORATION
                  A corporation incorporated under the laws of Canada,

                  hereinafter referred to "MKC"

AND:

                  MITEL NETWORKS CORPORATION
                  A corporation incorporated under the laws of Canada

                  hereinafter referred to as "MNC"

In this agreement, MKC and MNC may be collectively referred to as the "Parties."

WHEREAS:

A.    MNC and MKC executed a Research and Development Agreement (the "R&D
      Agreement"), effective as of the 27th day of March, 2001, pursuant to
      which MKC retained MNC to perform certain research and development work.

B.    The R&D Agreement may be terminated by the Parties at any time upon such
      terms as they may agree.

C.    The Parties have agreed to terminate the R&D Agreement.

NOW THEREFORE in consideration of the premises and mutual covenants herein
contained, and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the Parties hereto covenant and
agree as follows:

1.    Definitions

1.1   Except as expressly set out herein,  defined terms used in this  Agreement
      shall have the meanings accorded to them in the R&D Agreement.

1.2   For greater  certainty,  the Parties expressly  acknowledge and agree that
      the  "MKC  Technology"  does  not  include  any  technology  that has been
      independently  developed by MKC including the  technology  embodied in the
      Mitel Networks 3050 ICP and the  additional  work done to complete the SIP
      capable 5055 and 5056 IP phones from the working  prototype  stage reached
      by MNC,  all rights,  title,  interest  and  benefits in an to which shall
      remain vested in MKC.
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2.    Termination of R&D Agreement.

The Parties hereby agree to terminate the R&D Agreement pursuant to Clause 12.2
thereof ("Termination by Mutual Consent").

3.    Effect of Termination.

3.1   Except as provided in Clauses 3.2 below,  upon the  termination of the R&D
      Agreement,  neither party shall have any further obligations under the R&D
      Agreement.  MNC may, at its  discretion,  continue any of the research and
      development  activities  commenced  under  the R&D  Agreement  for its own
      account.  After the effective  date of this  Agreement,  MKC shall have no
      rights,  title or interest in or to any MKC  Technology,  whether  created
      prior to or after the termination of the R&D Agreement.

3.2   Sections 7.1 and 10 of the R&D Agreement  shall survive  termination,  and
      shall remain in full force and effect according to their terms.

IN WITNESS WHEREOF the Parties have caused this Agreement to be executed by
their duly authorized representatives as of the date first written above.

MITEL NETWORKS CORPORATION MITEL KNOWLEDGE CORPORATION


Per:                                Per:
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Name:                               Name:
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Date:                               Date:
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