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                                                                   EXHIBIT 10.9



                                SUMMA FOUR, INC.

                   1993 DIRECTOR STOCK OPTION PLAN, AS AMENDED


         1.       PURPOSE

                  The purpose of this 1993 Director Stock Option Plan (the
"Plan") of Summa Four, Inc. (the "Company") is to encourage ownership in the
Company by outside directors of the Company whose continued services are
considered essential to the Company's future progress and to provide them with a
further incentive to remain as directors of the Company.

         2.       ADMINISTRATION

                  The Board of Directors shall supervise and administer the
Plan. Grants of stock options under the Plan and the amount and nature of the
awards to be granted shall be automatic in accordance with Section 5. However,
all questions of interpretation of the Plan or of any options issued under it
shall be determined by the Board of Directors and such determination shall be
final and binding upon all persons having an interest in the Plan.

         3.       PARTICIPATION IN THE PLAN

                  Directors of the Company who are not employees of the Company
or any subsidiary of the Company shall be eligible to participate in the Plan.

         4.       STOCK SUBJECT TO THE PLAN

                  a.       The maximum number of shares which may be issued
under the Plan shall be 63,000 shares of the Company's Common Stock, par value
$.01 per share ("Common Stock"), subject to adjustment as provided in Section 9
of the Plan. All share amounts set forth in this Plan reflect the 3.5-for-1
stock split approved by the Board of Directors on July 14, 1993.

                  b.       If any outstanding option under the Plan for any
reason expires or is terminated without having been exercised in full, the
shares allocable to the unexercised portion of such option shall again become
available for grant pursuant to the Plan.

                  c.       All options granted under the Plan shall be
nonstatutory options not entitled to special tax treatment under Section 422 of
the Internal Revenue Code of 1986, as amended to date and as it may be amended
from time to time (the "Code").






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         5.       TERMS, CONDITIONS AND FORM OF OPTIONS

                  Each option granted under the Plan shall be evidenced by a
written agreement in such form as the Board of Directors shall from time to time
approve, which agreements shall comply with and be subject to the following
terms and conditions:

                  a.       OPTION GRANT DATES.

                  i.       Upon the initial election of any eligible director as
                           a director of the Company, the Company shall grant to
                           such director an option to purchase 7,000 shares of
                           Common Stock (the "Initial Option").

                  ii.      On the date of each annual meeting of stockholders of
                           the Company, the Company shall grant to each eligible
                           director an option to purchase 2,500 shares of Common
                           Stock (the "Annual Option").

                  b.       OPTION EXERCISE PRICE. The option exercise price per
share for each option granted under the Plan shall equal (i) the last reported
sales price per share of the Company's Common Stock on the NASDAQ National
Market System (or, if the Company is traded on a nationally recognized
securities exchange on the date of grant, the reported closing sales price per
share of the Company's Common Stock by such exchange) on the date of grant (or
if no such price is reported on such date such price as reported on the nearest
preceding day) or (ii) if the Common Stock is not traded on NASDAQ or an
exchange, the fair market value per share on the date of grant as determined by
the Board of Directors.

                  c.       OPTIONS NON-TRANSFERABLE. Each option granted under
the Plan by its terms shall not be transferable by the optionee otherwise than
by will, or by the laws of descent and distribution, and shall be exercised
during the lifetime of the optionee only by him. No option or interest therein
may be transferred, assigned, pledged or hypothecated by the optionee during his
lifetime, whether by operation of law or otherwise, or be made subject to
execution, attachment or similar process.

                  d.       EXERCISE PERIOD. Each Initial Option shall become
exercisable on a cumulative basis as to one-fifth of the shares subject to the
option on the date of grant of such option and each of the first, second, third
and fourth anniversaries of the date of grant. Each Annual Option shall be fully
exercisable on the date of grant. In the event an optionee ceases to serve as a
director, each such option may be exercised by the optionee (or, in the event of
his death, by his administrator, executor or heirs), at any time within 12
months after the optionee ceases to serve as a director, to the extent such
option was exercisable at the time of such cessation of



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service. Notwithstanding the foregoing, no option shall be exercisable after
the expiration of ten years from the date of grant.

                  e.       EXERCISE PROCEDURE. Options may be exercised only by
written notice to the Company at its principal office accompanied by (i) payment
in cash of the full consideration for the shares as to which they are exercised
or (ii) an irrevocable undertaking by a broker to deliver promptly to the
Company sufficient funds to pay the exercise price or delivery of irrevocable
instructions to a broker to deliver promptly to the Company cash or a check
sufficient to pay the exercise price.

         6.       ASSIGNMENTS

                  The rights and benefits of participants under the Plan may not
be assigned, whether voluntarily or by operation of law, except as provided in
Section 5(d).

         7.       EFFECTIVE DATE

                  The Plan shall become effective immediately upon its adoption
by the Board of Directors, but all grants of options shall be conditional upon
the approval of the Plan by the stockholders of the Company within 12 months
after adoption of the Plan by the Board of Directors.

         8.       LIMITATION OF RIGHTS

                  a.       NO RIGHT TO CONTINUE AS A DIRECTOR. Neither the Plan,
nor the granting of an option nor any other action taken pursuant to the Plan,
shall constitute or be evidence of any agreement or understanding, express or
implied, that the Company will retain a director for any period of time.

                  b.       NO STOCKHOLDERS' RIGHTS FOR OPTIONS. An optionee
shall have no rights as a stockholder with respect to the shares covered by his
options until the date of the issuance to him of a stock certificate therefor,
and no adjustment will be made for dividends or other rights (except as provided
in Section 9) for which the record date is prior to the date such certificate is
issued.

         9.       CHANGES IN COMMON STOCK

                  If the outstanding shares of Common Stock are increased,
decreased or exchanged for a different number or kind of shares or other
securities, or if additional shares or new or different shares or other
securities are distributed with respect to such shares of Common Stock or other
securities, through merger, consolidation, sale of all or substantially all of
the assets of the Company, reorganization, recapitalization, reclassification,
stock dividend, stock split, reverse stock split or




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other distribution with respect to such shares of Common Stock, or other
securities, an appropriate and proportionate adjustment will be made in (i) the
maximum number and kind of shares reserved for issuance under the Plan, (ii) the
number and kind of shares or other securities subject to then outstanding
options under the Plan and (iii) the price for each share subject to any then
outstanding options under the Plan, without changing the aggregate purchase
price as to which such options remain exercisable. No fractional shares will be
issued under the Plan on account of any such adjustments.

         10.      CHANGE IN CONTROL

                  Notwithstanding any other provision to the contrary in this
Plan, in the event of a Change of Control (as defined below), all options
outstanding as of the date such Change in Control occurs shall become
exercisable in full, whether or not exercisable in accordance with their terms.
A "Change in Control" shall occur or be deemed to have occurred only if any of
the following events occur: (i) any "person," as such term is used in Sections
13(d) and 14(d) of the Securities Exchange Act of 1934, as amended (the
"Exchange Act") (other than the Company, any trustee or other fiduciary holding
securities under an employee benefit plan of the Company, or any corporation
owned directly or indirectly by the stockholders of the Company in substantially
the same proportion as their ownership of stock of the Company) is or becomes
the "beneficial owner" (as defined in Rule 13d-3 under the Exchange Act),
directly or indirectly, of securities of the Company representing 50% or more of
the combined voting power of the Company's then outstanding securities; (ii)
individuals who, as of the date this Plan is adopted, constitute the Board of
Directors of the Company (as of the date thereof, the "Incumbent Board") cease
for any reason to constitute at least a majority of the Board, provided that any
person becoming a director subsequent to the date thereof whose election, or
nomination for election by the Company's stockholders, was approved by a vote of
at least a majority of the directors then comprising the Incumbent Board (other
than an election or nomination of an individual whose initial assumption of
office is in connection with an actual or threatened election contest relating
to the election of the directors of the Company, as such terms are used in Rule
14a-11 of Regulation 14A under the Exchange Act) shall be, for purposes of this
Agreement, considered as though such person were a member of the Incumbent
Board; (iii) the stockholders of the Company approve a merger or consolidation
of the Company with any other corporation, other than (A) a merger or
consolidation which would result in the voting securities of the Company
outstanding immediately prior thereto continuing to represent (either by
remaining outstanding or by being converted into voting securities of the
surviving entity) more than 50% of the combined voting power of the voting
securities of the Company or such surviving entity outstanding immediately after
such merger or consolidation or (B) a merger or consolidation effected to
implement a recapitalization of the Company (or similar transaction) in which no
"person" (as hereinabove defined) acquires more than 30% of the combined voting
power of the Company's then



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outstanding securities; or (iv) the stockholders of the Company approve a plan
of complete liquidation of the Company or an agreement for the sale or
disposition by the Company of all or substantially all of the Company's assets.

         11.      AMENDMENT OF THE PLAN

                  The Board of Directors may suspend or discontinue the Plan or
review or amend it in any respect whatsoever; provided, however, that without
approval of the stockholders of the Company no revision or amendment shall
change the number of shares subject to the Plan (except as provided in Section
9), change the designation of the class of directors eligible to receive
options, or materially increase the benefits accruing to participants under the
Plan. The Plan may not be amended more than once in any six-month period.

         12.      NOTICE

                  Any written notice to the Company required by any of the
provisions of the Plan shall be addressed to the Treasurer of the Company and
shall become effective when it is received.

         13.      GOVERNING LAW

                  The Plan and all determinations made and actions taken
pursuant hereto shall be governed by the laws of the State of New Hampshire.





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                                   Adopted by the Board of Directors 
                                   on June 7, 1993.

                                   Approved by the stockholders 
                                   on August 16, 1993.

                                   Amended by the Board of Directors 
                                   on May 1, 1995.

                                   Amendment approved by stockholders 
                                   on July 21, 1995.





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