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                                                                    EXHIBIT 10.4



                             INTERFACE SYSTEMS, INC.
                          EMPLOYEE STOCK PURCHASE PLAN



         1.     Purpose. The purpose of the Interface Systems, Inc. Employee
Stock Purchase Plan (the "Plan") is to promote the best interests of Interface
Systems, Inc. (the "Company") and its stockholders by encouraging employees of
the Company to acquire a proprietary interest in the Company, thus identifying
their interests with those of stockholders and encouraging the employees to make
even greater efforts on behalf of the Company. The Plan is intended to
constitute an "employee stock purchase plan" under Section 423 of the Internal
Revenue Code of 1986, as amended (the "Code").

         2.     Certain Definitions. As used in this Plan, the term "employee"
means an individual with an "employment relationship" with the Company as
defined in Regulation 1.421-7(h) of the Income Tax Regulations; the term 
"employment" means employment with the Company, the term "Purchase Period" means
a six month offering period commencing each June 1 and December 1; and the term
"compensation" means cash compensation, not including overtime and bonuses.

         3.     Stock. The stock subject to option and purchase under the Plan
shall be the Common Stock of the Company (the "Common Stock") and may be either
authorized and unissued shares or shares that have been reacquired by the
Company. The total amount of Common Stock on which options may be granted under
the Plan shall not exceed 225,000 shares, subject to adjustment in accordance
with Section 12. Shares of Common Stock subject to any unexercised portion of a
terminated, canceled or expired option granted under the Plan may again be used
for option grants under the Plan.

         4.     Administration. The Plan shall be administered by the
Compensation Committee (the "Committee") of the Board of Directors ("Board"),
comprised of nonemployee members of the Board, as defined in Rule 16b-3
promulgated under the Securities Exchange Act of 1934, as amended ("Exchange 
Act"). The Committee may prescribe rules and regulations from time to time for 
the administration of the Plan and may decide questions which may arise with
respect to its interpretation or application. The decisions of the Committee in 
interpreting the Plan shall be final, conclusive and binding on all persons, 
including the Company, its employees and optionees. In the event of insufficient
shares during a Purchase Period, the Committee shall allocate shares 
proportionately on the basis of compensation.

         5.     Participants. (a) Except as provided in Section 6, below, any
employee who is employed by the Company on the first day of a Purchase Period is
eligible to participate in the Plan in accordance with its terms.


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         6.     Ownership and Purchase Limitations. Notwithstanding anything
herein to the contrary, no employee shall be entitled to participate in an
offering under the Plan if such employee, immediately after a grant under this
Plan, would, in the aggregate, own or hold options to purchase shares of Common
Stock equal to or exceeding five percent (5%) or more of the total combined
voting power or value of all classes of stock of the Company or of its
subsidiary corporations. For the foregoing purposes, the rules of Section 424(d)
of the Code shall apply in determining stock ownership. With respect to
individual employees, Section 424(d) provides that an employee shall be
considered as owning the stock owned directly or indirectly, by or for his
brothers and sisters (whether by the whole or half blood), spouse, ancestors,
and lineal descendants. No employee shall be granted an option under the Plan
which, together with options granted under all employee stock purchase plans
(qualified under Section 423 of the Code) of the Company and its subsidiaries
permits the employee to accrue option rights to purchase shares in any calendar
year in excess of $25,000 of fair market value of such shares (determined at the
time the option is granted). For purposes of this Plan, the "grant date" shall
be the first day of each Purchase Period, as defined in Section 9(b), below. The
Company's non-employee directors are not eligible to participate in the Plan.

         7.     Option Price. The option price of the shares shall be the lower
of 85% the fair market value of the Common Stock on first day of the Purchase
Period or 85% of the fair market value of the Common Stock on the last day of
the Purchase Period. For purposes of this paragraph, the fair market value as of
any date and in respect of any share of Common Stock shall be the last sale
price of the Common Stock on The Nasdaq Stock Market, National Market (the
"National Market"), on the date of determination or, if no such reported sale of
the Stock shall have occurred on such date on the National Market, on the
preceding date on which there was such a reported sale on such National Market.

         8.     Payment for Option Shares.

                (a)      Shares Under Option. An eligible employee may elect to
participate in an offering by filing with the Human Resources Department a
payroll deduction form within the election period designated by the Company
prior to each Purchase Period (the "Election Period"). An eligible employee's
election to participate and payroll deduction form from the preceding Election
Period automatically shall carry over to the next Election Period unless
affirmatively revoked by the employee. An employee who elects to participate may
not authorize payroll deductions which, in the aggregate, are less than one
percent (1%) of the employee's cash compensation during the Purchase Period (not
including overtime and bonus payments) or are more than 15% of the employee's
cash compensation during the Purchase Period (not including overtime and bonus
payments). Only whole shares of' Common Stock may be purchased under the Plan.

                (b)      A participating employee must authorize payroll
deductions over a six month Period beginning on June 1 or December 1 (the
"Purchase Period"). Purchase Periods automatically shall run successively unless
designated otherwise by the Company. An employee may suspend payroll deductions
during a Purchase Period at any time upon written notice to the Human Resources

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Department which shall become effective no later than the next payroll period
following the suspension; provided, however, that payroll deductions made prior
to the suspension shall still be used to purchase Common Stock for the employee
at the end of the Purchase Period. Upon suspension of such deductions, no
further deductions will be made during the Purchase Period or any future
Purchase Periods unless the employee submits the appropriate form to the Human
Resources Department electing to again participate in the Plan.

                (c)      Payroll deductions shall commence on the first payroll
date in the Purchase Period and shall continue until the last payroll date in
the Purchase Period; provided, however, that unless an election is revoked, such
election shall continue into successive six month Purchase Periods.

                (d)      A participating employee's option shall be deemed to
have been exercised on the last business day of the Purchase Period.

                (e)      The Company retains the right to designate an exclusive
broker to handle the Common Stock transactions under the Plan. As soon as
practicable after the end of the Purchase Period, the Company shall deliver to
each employee or a designated brokerage account, through a certificate or
electronic transfer, the shares of Common Stock that such employee has
purchased. Any amount that has been deducted and withheld in excess of the
option price automatically shall be applied toward the purchase of option shares
in the next Purchase Period. An employee who elects not to participate in the
following Purchase Period shall receive a check from the Company for any amount
that has been deducted and withheld in excess of the cost of shares.

         9.     Interest. No interest shall accrue or be paid on any amounts
paid by payroll deduction by any participating employee.

         10.    Termination of Employment, Unpaid Leave of Absence or Layoff. If
a participating employee ceases to be employed by the Company for any reason
(with or without severance pay), including but not limited to, voluntary or
forced resignation, retirement, death, layoff, or if an employee is on an unpaid
leave of absence, or during any period of severance, within a reasonable time
after notice of the termination or unpaid leave of absence, the Company shall
issue a check to the former employee (or executor, administrator or legal
representative, if applicable) in the aggregate amount of the employee's payroll
deductions that had not yet been applied towards the purchase of shares as of
the employee's date of separation.

         11.    Non-Assignability. No option shall be transferable by an
employee, and an option shall be exercised only by an employee. Upon the death
of a participating employee, his or her executor, administrator or other legal
representative shall receive a check from the Company representing the aggregate
amount of the deceased employee's payroll deductions that had not yet been
applied towards the purchase of option shares as of the date of death.


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         12.    Adjustments. The total amount of Common Stock for which options
may be granted under the Plan, and the number of shares subject to any option
granted to a participant (both as to the number of shares of Common Stock and
the option price), shall be appropriately adjusted for any increase or decrease
in the number of outstanding shares of Common Stock resulting from payment of a
stock dividend on Common Stock, a subdivision or combination of shares of Common
Stock, or a reclassification of Common Stock, and, pursuant to the paragraph
below, in the event of a merger in which the Company shall be the surviving
corporation.

         After any merger of one or more corporations into the Company, or after
any consolidation of the Company and one or more corporations in which the
Company shall be the surviving corporation, each participant shall, at no
additional cost, be entitled upon the exercise of an option, to receive (subject
to any required action by stockholders), in lieu of the number of shares to
which such option shall then be exercised, the number and class of shares of
stock or other securities to which such participant would have been entitled to
receive pursuant to the terms of the agreement of merger or consolidation if at
the time of such merger or consolidation such participant had been a holder of
record of a number of shares of Common Stock equal to the number of shares to
which such option shall then be so exercised. Comparable rights shall accrue to
each participant in the event of successive mergers or consolidations of the
character described above.

         Anything contained herein to the contrary, upon the dissolution or
liquidation of the Company or upon any merger or consolidation in which the
Company is not the surviving corporation, the Purchase Period for any option
granted under this Plan shall terminate as of the date of the aforementioned
event, but each participant who is then an employee of the Company or a
subsidiary shall have the right, immediately prior to such dissolution,
liquidation, merger or consolidation, to exercise his option for such Purchase
Period in full on the earlier of the date of the merger or liquidation or the
last day of the Purchase Period.

         The foregoing adjustments and the manner of application of the
foregoing provisions shall be determined by the Committee in its sole
discretion. Any such adjustment may provide for the elimination of any
fractional share which might otherwise become subject to an option.

         13.    Termination and Amendment. The Board may terminate the Plan, or
the granting of options under the Plan, at any time. No option shall be granted
under the Plan after October 30, 2007.

         The Board may amend or modify the Plan at any time and from time to
time, but no amendment or modification shall disqualify the Plan under Section
423 of the Code.

         No amendment, modification, or termination of the Plan shall in any
manner affect any option granted under the Plan without the consent of the
participant holding the option.

         14.    Rule 16b-3 Requirements. Notwithstanding any other provision of
the Plan, the Committee may impose such conditions on the exercise of an option
as may be required to satisfy

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the requirements of Rule 16b-3 of the Exchange Act, as amended from time to time
(or any successor rule).

         15.    Rights Prior to Delivery of Shares. No participant shall have
any rights as a stockholder with respect to shares covered by an option until
the issuance of a stock certificate or electronic transfer to the employee or
his brokerage account of such shares. No adjustment shall be made for dividends
or other rights with respect to such shares for which the record date is prior
to the date the certificate is issued or the shares electronically delivered to
a brokerage account.

         16.    Securities Laws. Anything to the contrary herein
notwithstanding, the Company's obligation to sell and deliver stock pursuant to
the exercise of an option is subject to such compliance with federal and state
laws, rules and regulations applying to the authorization, issuance or sale of
securities as the Company deems necessary or advisable. The Company shall not be
required to sell and deliver stock unless and until it receives satisfactory
assurance that the issuance or transfer of such shares will not violate any of
the provisions of the Securities Act of 1933 or the Exchange Act, or the rules
and regulations of the Securities Exchange Commission promulgated thereunder or
those of any stock exchange on which the stock may be listed, the provisions of
any state laws governing the sale of securities, or that there has been
compliance with the provisions of such acts, rules, regulations and laws.

         The Committee may impose such restrictions on any shares of Common
Stock acquired pursuant to the exercise of an option under the Plan as it may
deem advisable, including, without limitation, restrictions (a) under applicable
federal securities laws, (b) under the requirements of any stock exchange or
other recognized trading market upon which such shares of Common Stock are then
listed or traded, and (c) under any blue sky or state securities laws applicable
to such shares. No shares shall be issued until counsel for the Company has
determined that the Company has complied with all requirements under appropriate
securities laws.

         17.    Approval of Plan. The Plan shall be subject to the approval of
at least a majority of the votes cast by the holders of the Company's Common
Stock entitled to vote at a meeting of stockholders of the Company held within
12 months after the October 31, 1997 adoption of the Plan by the Board. If not
approved by stockholders within such 12-month period, the Plan and any options
granted hereunder shall become void and of no effect, and the participating
employees shall receive a check from the Company for all payroll deductions
relating to the Plan.

         18.    Effect on Employment. Neither the adoption of the Plan nor the
granting of an option pursuant to it shall be deemed to create any right in any
employee to be retained or continued in the employment of the Company.

         19.    Use of Proceeds. The proceeds received from the sale of shares
of Common Stock pursuant to the Plan shall be used for corporate purposes by the
Company.

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         THIS EMPLOYEE STOCK PURCHASE PLAN is hereby executed on this the 21st
day of November, 1997.



                                         INTERFACE SYSTEMS, INC.



                                         By:/s/ Robert A. Nero
                                            ------------------------------------
                                            Robert A. Nero
                                            President



                  BOARD OF DIRECTORS APPROVAL: October 31, 1997
                      STOCKHOLDER APPROVAL: March 20, 1998









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