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                                                                   EXHIBIT 10.50


                                     FORM OF
                         FOUNDER STOCK PLEDGE AGREEMENT

         PLEDGE AGREEMENT dated as of September 8, 2000 between ________________
("Pledgor") and Adir Technologies, Inc., a Delaware corporation (the "Pledgee"
or the "Company").

         Pursuant to a promissory note secured by a pledge of stock dated the
date hereof, a copy of which is attached hereto (the "Note"), the Pledgee has
loaned to Pledgor $_________. Pledgor desires to pledge, as security for its
repayment obligation under the Note, ____ shares of Common Stock of the Company,
as set forth in Schedule I attached hereto. The shares of Common Stock of the
Company pledged hereunder are collectively referred to as the "Shares."

         In consideration of the foregoing and the mutual covenants and
conditions contained herein, the parties hereto agree as follows:

         1. GRANT OF SECURITY INTEREST. Pledgor, as security for the due
performance by Pledgor of all of the agreements and obligations to be performed
and kept by Pledgor under the Note and this Pledge Agreement, hereby assigns,
hypothecates, transfers, and pledges to the Pledgee and hereby creates a present
security interest in favor of the Pledgee in the Shares.

         2. CERTIFICATES REPRESENTING PLEDGED SECURITIES. Pledgor hereby
delivers to the Pledgee a certificate or certificates representing the Shares
with undated, executed blank stock power(s) attached.

         3. ADDITIONAL STOCK. If, on or subsequent to the date hereof, the
Common Stock of the Company is increased, decreased, changed into or exchanged
for a different number or kind of shares or securities of the Company or any
other corporation through reorganization, recapitalization, reclassification,
stock dividend, stock split or reverse stock split, or otherwise, such shares or
securities shall be delivered to the Pledgee, together with duly executed stock
powers in blank, to be held subject to all the terms and conditions of this
Pledge Agreement, in addition to or in substitution for the certificates
representing the Shares delivered pursuant to Section 2 hereof, and the term
"Shares" shall also be deemed to refer to such shares or securities.

         4. VOTING AND DIVIDEND RIGHTS. While the Shares are in the possession
of the Pledgee and unless and until a Default (as defined in the Note) or a
breach of this Pledge Agreement occurs (collectively, a "default"), the Pledgor
shall retain each and all of the voting rights and dividend rights of the
Shares. The transfer of the voting rights of the Shares as contemplated hereby
shall constitute an irrevocable proxy coupled with an interest for as long as
and to the extent that the Pledgor is in default under the Note or this Pledge
Agreement. Upon the cure of such default, the voting rights and dividend rights
shall be transferred back to and exercisable by Pledgor until a further default
occurs, if any.

         5. DEFAULT. Subject to the limitations set forth in the Note, upon
Pledgor's default under the Note or this Pledge Agreement, the Pledgee shall
have all rights and remedies of a secured party under the Uniform Commercial
Code as in effect in the State of New Jersey, including the right to exercise
and enjoy the voting and dividend rights of the Shares, in addition


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to the rights and remedies provided in this Agreement. All of the rights of the
Pledgee under this Pledge Agreement and the Note shall be cumulative and the
election of any one or more remedies shall not bar any other remedy or remedies.

         6. LIMITATION. Neither the Pledgee nor any assignee of the Pledgee
shall subject the Shares to a put, call, or other option or buy-sell or similar
arrangement other than those in effect on the date hereof.

         7. RELEASE OF PLEDGE. On repayment of all principal and accrued
interest on the Note, the certificates, stock powers, and other evidence
representing the Shares shall thereupon be released from pledge and delivered to
Pledgor.

         8. SUBSTITUTION OF COLLATERAL. At any time and from time to time, upon
request of Pledgor, the Pledgee may, in its sole discretion, release all or any
part of the Shares and accept substitute collateral for the pledged stock,
without affecting the liability or obligations of Pledgor or any other person
for payment of the indebtedness secured hereby.

         9. WARRANTY OF PLEDGOR. Pledgor warrants and represents that it is the
record and beneficial owner of the Shares, with full power and authority to
enter into this Pledge Agreement and to grant a security interest in the Shares
to the Pledgee as contemplated hereby. The Shares are not subject to any other
security interest or to any lien, encumbrance or adverse claim.

         10. NOTICES. All notices, demands or other communications to be given
or delivered under or by reason of the provisions of this Agreement will be in
writing and will be deemed to have been given when delivered personally, or one
business day following when sent next-day delivery via a nationally recognized
overnight courier, or when sent, when sent via facsimile confirmed in writing to
the recipient. Such notices, demands and other communications will be sent to
the address indicated below:

                  To the Pledgee:

                           Adir Technologies, Inc.
                           520 Broad Street
                           Newark, NJ 07102
                           Attn:  President
                           Facsimile: (973) ___-____

                  To the Pledgor:

                           _________________________
                           Net2Phone, Inc.
                           520 Broad Street
                           Newark, NJ 07102
                           Attn:  President
                           Facsimile: (973) ___-____


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or such other address or to the attention of such other Person as the recipient
party shall have specified by prior written notice to the sending party.

         11. COUNTERPARTS. This Pledge Agreement may be executed in
counterparts, each of which shall be an original but all of which shall
constitute one and the same instrument.

         12. GOVERNING LAW. This Note shall be construed in accordance with the
domestic laws of the State of New Jersey, without giving effect to any choice of
law or conflict of law provision or rule (whether of the State of New Jersey or
any other jurisdiction) that would cause the application of the laws of any
jurisdiction other than the State of New Jersey.

         13. MODIFICATIONS AND AMENDMENTS. This Pledge Agreement may not be
modified, changed or supplemented, nor may any obligations hereunder be waived,
except by written instrument signed by the party to be charged or by its agent
duly authorized in writing or as otherwise expressly permitted herein.

         14. NO THIRD PARTY RIGHTS. The parties do not intend to confer any
benefit hereunder on any person, firm or corporation other than the parties
hereto.

         15. WAIVERS AND EXTENSIONS. No waiver of any breach of any agreement or
provision herein contained shall be deemed a waiver of any preceding or
succeeding breach hereof or of any other agreement or provision herein
contained. No extension of time for performance of any obligations or acts shall
be deemed an extension of the time for performance of any other obligations or
acts.

         16. NON-WAIVER OF RIGHTS. No failure or delay of either party in the
exercise of any right given to such party hereunder shall constitute a waiver
thereof unless the time specified herein for exercise of such right has expired,
nor shall any single or partial exercise of any right preclude other or further
exercise thereof or of any other right.

         17. TITLES AND HEADINGS. Titles and headings of sections of this Pledge
Agreement are for convenience of reference only and shall not affect the meaning
or interpretation of any provision of this Pledge Agreement.

         18. FURTHER ASSURANCES. The parties agree to do such further acts and
things and to execute and deliver such additional agreements and instruments as
may reasonably be required to consummate, evidence, or confirm the agreement
contained herein in the manner contemplated hereby.

         19. SUCCESSORS AND ASSIGNS. This Pledge Agreement shall be binding upon
and inure to the benefit of the heirs, representatives, successors, and assigns
of the parties, provided however, that this Pledge Agreement may not be assigned
by the Pledgor without the prior written consent of the Pledgee.

         20. SEVERABILITY. Every provision of this Pledge Agreement is intended
to be severable. In the event any term or portion hereof is declared to be
illegal or invalid for any


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reason whatsoever by a court of competent jurisdiction, such illegality or
invalidity shall not affect any other term or portion of this Pledge Agreement,
which shall remain binding and enforceable.

         21. CONSENTS AND APPROVALS. Wherever the consent or approval of either
party is provided for in this Pledge Agreement, such consent or approval may not
unreasonably be withheld and shall be given in writing to the requesting party.

                                    * * * * *


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         IN WITNESS WHEREOF, the parties hereto have executed this Pledge
Agreement as of the date first above written.



                                       ______________________________



                                       ADIR TECHNOLOGIES, INC.



                                       By: _____________________________________
                                       Name: ___________________________________
                                       Title: __________________________________
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                                                                      SCHEDULE I


<TABLE>
<CAPTION>
       CERTIFICATE NUMBER OF
         THE PLEDGED SHARES                      NUMBER OF SHARES
<S>                                              <C>

</TABLE>