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                                                                   EXHIBIT 10.15
                         EXECUTIVE EMPLOYMENT AGREEMENT

           AGREEMENT, dated and entered into as of the 13th day of January,
1997, by and between Voicetek Corporation , a Massachusetts corporation (the
"Company"), and Daniel Poranski, an individual residing at 137 Linebrook Road,
Ipswich, MA 01938 (the "Executive").

           WHEREAS, the Company desires to engage the full-time services of the
Executive;

           WHEREAS, the Executive desires to be so employed by the Company; and

           WHEREAS, the Company desires to be assured that the unique and expert
services of the Executive will be available solely to the Company on such
full-time basis, and that the Executive is willing and able to render such
services on the terms and conditions hereinafter set forth.

           NOW, THEREFORE, in consideration of such employment and the mutual
covenants and promises herein contained, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
Company and the Executive agree as follows:

           Section 1. Employment. The Company hereby employs the Executive as
its Vice President of Marketing, and the Executive hereby accepts such
employment under and subject to the terms and conditions hereinafter set forth.
The Executive further agrees to serve as a member of the Board of Directors (the
"Board") of the Company if elected or appointed to such office in accordance
with the Company's By-Laws.

           Section 2. Term. Unless sooner terminated as provided in Section 7,
the term of employment under this Agreement shall begin on the date hereof and
shall conclude on
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January 12, 2000 (the "Term").

           Section 3. Duties. The Executive shall serve as Vice President of
Marketing, and he shall perform additional duties as the Board of Directors or
the President of the Corporation may assign to him from time
to time. The Executive hereby agrees to devote his full business time and best
efforts to the faithful performance of such duties and to the promotion and
forwarding of the business and affairs of the Company for the Term.

           Section 4. Salary Compensation. In consideration of the services
rendered by the Executive under this Agreement, the Company shall pay the
Executive a base salary (the "Base Salary") at the rate of One Hundred
Thirty-Two Thousand Dollars ($132,000) per calendar year. The Base Salary shall
be paid in such installments and at such times as the Company pays its regularly
salaried key executive employees, and the Board may change the Base Salary from
time to time in its sole discretion; provided, however, that in no event shall
the Base Salary for any calendar year be less than the Base Salary in effect for
the immediately prior calendar year. 

           Section 5. Bonus Compensation. The Executive shall be entitled to
receive such incentive or performance bonuses as the Board may determine from
time to time.

           Section 6. Fringe Benefits. As a key executive employee of the
Company, the Executive shall be eligible to participate in all employee fringe
benefit programs as are made available from time to time to the Company's key
executive employees.

           Section 6. Benefits. In addition to the compensation detailed in
Section 4 and 5 of this Agreement, the Executive shall be entitled to the
following additional benefits:

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           Section 6.01. Paid Vacation. The Executive shall be entitled to
fifteen (15) business days paid vacation per calendar year. The Executive shall
be entitled to an additional vacation day for each full year during which the
Executive has been in the full time employment of the Company, with an
additional vacation day per year granted upon each subsequent anniversary of the
commencement of the Executive's full time employment with the Company, which
occurred on April 1, 1996; provided that the number of paid vacation days to
which the Executive shall be entitled in a calendar year shall not exceed twenty
(20) business days. Such vacation shall extend for such periods and shall be
taken at such intervals as shall be appropriate and consistent with the proper
performance of the Executive's duties hereunder and consistent with the
Company's vacation policy.

           Section 6.02. Insurance Coverage. During the Term, the Company shall
provide the Executive with group health, dental and life insurance protection to
the same extent that it makes such protection available to its other key
executive employees.

           Section 6.03. Reimbursement of Expenses. The Company shall reimburse
the Executive for all reasonable expenses actually incurred by the Executive in
connection with the business affairs of the Company and the performance of his
duties hereunder. The Executive shall comply with such reasonable limitations
and reporting requirements with respect to such expenses as the Board may
establish from time to time.

           Section 6.04. Disability and Other Benefits. If the Executive suffers
any illness, disability or incapacity which prevents the Executive from
performing the Executive's duties hereunder, and such illness, disability or
incapacity shall be deemed by a duly licensed physician

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(who may be the Executive's personal physician) to be permanent; or, if the
Executive is unable to render full-time services to the Company of the character
required hereunder for a period of six (6) consecutive months by reason of
illness, disability or incapacity, and the Board has determined that the
Executive has been permanently disabled; then, and in either of such events, the
Executive shall render such advisory and consulting services to the Company as
may be reasonably requested of the Executive by the Board and officers of the
Company but only to the extent that the Executive is able to perform such
services. In such event, the Executive shall be paid the amount of One Hundred
Thirty-Two Thousand Dollars ($132,000) annually, payable in equal installments
in conformity with the Company's normal payroll period. Such disability
compensation shall commence upon the first day of the first month following the
determination that the Executive's illness, disability or incapacity is
permanent, and shall be paid for the balance of the Term even if the Executive's
Employee's illness, disability or incapacity prevents the rendering by the
Executive of any services to the Company and continues for the entire remaining
Term. During such periods of disability, the Company reserves the right to, at
its own expense, have a licensed physician examine the person of the Executive
when and as often as it may reasonably require to determine if the Executive is
permanently disabled. The Executive's disability compensation hereunder shall be
reduced by the amount of any disability insurance proceeds paid to or for the
benefit of the Executive under any policy, the premiums for which have been paid
by the Company. The Executive will also be provided with those other benefits
generally equivalent to those made available to key executive employees
performing similar functions for similarly situated companies.

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           Section 7. Termination. This Agreement shall be terminated at the end
of the Term, or earlier as follows:

           Section 7.01. Death. This Agreement shall terminate upon the death of
the Executive, except that the compensation provided in Section 4 shall continue
through the end of the month in which the Executive's death occurs.

           Section 7.02. Permanent Disability. In the event of any physical or
mental disability of the Executive rendering the Executive unable to perform his
or her duties hereunder for a period of at least one hundred twenty (120)
consecutive days and the further determination that the disability is permanent
with regard to the Executive's ability to return to work in his or full
capacity, this Agreement shall terminate automatically. Any determination of
disability shall be made by the Board in consultation with a qualified physician
or physicians selected by the Board and reasonably acceptable to the Executive.

           Section 7.03. By The Company For Cause. The employment of the
Executive may be terminated by the Company for Cause (as defined below) at any
time effective upon written notice to the Executive. The Company shall provide
the Executive with at least ten (10) business days' prior written notice of a
Board meeting at which a termination for Cause will be considered and the
Executive will have an opportunity to attend and participate in that meeting.
For purposes hereof, the term "Cause" shall mean that the Board has determined
that any one or more of the following has occurred:

                    (a) The Executive shall have been convicted of, or shall
                    have pleaded guilty or nolo contendere to, any felony or a
                    crime involving moral turpitude;

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                    (b) The Executive shall have repeatedly failed or refused to
                    perform his duties hereunder and such failure or refusal
                    shall have continued for a period of ten (10) days following
                    written notice from the Board, it being understood that the
                    Company's failure to achieve its business plan or
                    projections shall not itself be considered a failure or
                    refusal to perform duties;

                    (c) the Executive shall have intentionally committed any
                    fraud, embezzlement, misappropriation of funds, breach of
                    fiduciary duty or other act of dishonesty against the
                    Company which has a material adverse effect on the Company;
                    or

                    (d) the Executive shall have (i) failed to perform his
                    duties hereunder in a manner that is reasonably satisfactory
                    to the Board, (ii) refused to carry out the duties assigned
                    to him by the Board, or (iii) breached any one or more of
                    the material provisions of this Agreement, which failure,
                    refusal or breach shall have continued for a period of at
                    least ten (10) days after notice from the Company describing
                    such failure, refusal or breach in reasonable detail.

           Section 7.04. By the Company Without Cause. The Company may terminate
the Executive's employment at any time without Cause effective upon written
notice to the Executive.

           Section 7.05. Termination Without Cause Following Change of Control.
IN THE EVENT THE COMPANY UNDERGOES A CHANGE OF CONTROL, EACH OF THE FOLLOWING
EVENTS AT ANY TIME SUBSEQUENT TO SUCH CHANGE OF CONTROL SHALL BE DEEMED TO BE A
TERMINATION WITHOUT CAUSE: (i) ANY REDUCTION IN THE COMPENSATION PAYABLE TO THE
EXECUTIVE SET FORTH IN SECTION 4 HEREIN; (ii) ANY CHANGE IN THE LOCATION OF THE
PLACE OF WORK OF THE EXECUTIVE TO A LOCATION MORE THAN THIRTY MILES FROM
DOWNTOWN BOSTON; AND (iii) ANY VIOLATION BY THE COMPANY OF ANY PROVISION OF THIS
AGREEMENT.

           For purposes hereof a "Change of Control" shall mean the happening of
any of the following events: (i) an acquisition by any person or group of
persons of 50% or more of the

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combined voting power of the then outstanding securities entitled to vote
generally in the election of directors of the Company; (ii) the approval by the
Directors or Shareholders of the Company of a reorganization, merger or
consolidation or sale or other disposition of all substantially all of the
assets of the Company which would result in the voting securities of the Company
immediately prior to such transaction continuing to represent less than 50% of
the combined voting power of the securities entitled to vote generally in the
election of directors of the Company or such other entity outstanding
immediately after such transaction, or (iii) the members of the Board of
Directors of the Company (or their respective successors designated by the
stockholders which designated current members of the Board of Directors) on the
date hereof shall not constitute a majority of the Board of Directors of the
Company.

           Section 7.06. By the Executive Voluntarily. The Executive may
terminate this Agreement at any time effective upon at least fifteen (15)
business days' prior written notice to the Company.

           Section 8. Termination Payments and Benefits.

           Section 8.01. Voluntary Termination, Termination For Cause. Upon any
termination of this Agreement: (1) voluntarily by the Executive or (2) by the
Company for Cause as provided in Section 7.04, all payments, salary and other
benefits hereunder shall cease at the effective date of termination except as
specifically provided in this Section 8.02.

           Section 8.02. Termination without Cause, Company Election Not To
Renew, Death, Disability In the event that this Agreement is terminated by the
Company without Cause, or because of the death or permanent disability of the
Executive, the Executive shall receive as a 

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termination settlement an amount equal to six (6) month's salary as is in effect
at the effective date of termination (the "Termination Payment"). The
Termination Payment shall be paid in six (6) monthly installments on the first
business day of each month following the effective date of termination. If six
(6) months following the termination, the Executive has not obtained employment
with similar salary, benefits and responsibilities as described herein, the
Executive shall receive as an additional termination settlement an amount equal
to six (6) month's salary (the "Additional Termination Payment"); provided,
however, such Additional Termination Payment shall be mitigated by the amount of
salary the Executive shall receive during such additional six (6) month period.
The Termination Payment shall be reduced by any statutorily-mandated severance,
change of control, plant closing, or similar payment to the Executive by the
Company or its stockholders. In addition to the Termination Payment, the
Executive shall continue to receive the insurance benefits included as part of
the fringe benefits referenced in Section 6 for a period of six (6) months
following the effective date of termination and any death and disability
benefits hereunder for a period of (eighteen) 18 months following the effective
date of termination.

           Section 8.03. Acceleration of Options. In the event the Executive's
employment terminates for any reason, other than for Cause or voluntarily by the
Executive, any and all options to purchase Common Stock held by the Executive
shall immediately vest and become fully exercisable. In addition, in the event
the Company undergoes a Change of Control, all options of the Executive to
purchase Common Stock of the Company which, by the terms of the grant of such
options otherwise would become exercisable within one year following the date of

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the Change of Control, shall become exercisable upon the Change of Control, and
all other options shall become exercisable one year earlier than provided for in
the grant of such options.

           Section 8.04. Health and Life Insurance. In the event the Executive's
employment terminates for any reason, other than for Cause, the Company shall
continue to provide the Executive the benefits set forth in Section 6.02 hereof
for a period of six (6) months following the date of such termination.

            Section 8.05. Outplacement Assistance. In the event the Executive's
employment terminates for any reason , other than for Cause, the Company shall
provide outplacement assistance to the Executive as is then reasonable and
customary for similarly situated businesses up to a $15,000 maximum expenditure
by the Company.

            Section 8.06. Public Statement of Termination. In the event the
Executive's employment terminates for any reason, the Company and the Executive
shall agree upon a public statement pertaining to the Executive's termination of
employment, and the terms of said statement shall not be subject to subsequent
modification by either party unless required by law; provided, however, that in
the event the Company and the Executive are unable in good faith to agree on
such a statement, the Company may make public statements as are necessary to
comply with the law.

           Section 8.07. No Other Benefits. Except as specifically provided in
this section 8, the Executive shall not be entitled to any compensation,
severance or other benefits from the Company upon the termination of this
Agreement for any reason whatsoever.

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           Section 9. Merger Clause. The Company shall not consolidate, merge or
transfer all or a substantial portion of its assets without requiring the
transferee to assume this Agreement and the obligations hereunder.

           Section 10. Severable Provisions. The provisions of this Agreement
are severable and the invalidity of any one or more provisions shall not affect
the validity of any other provision. In the event that a court of competent
jurisdiction shall determine that any provision of this Agreement or the
application thereof is unenforceable in whole or in part because of the duration
or scope thereof, the parties hereto agree that said court in making such
determination shall have the power to reduce the duration and scope of such
provision to the extent necessary to make it enforceable, and that the Agreement
in its reduced form shall be valid and enforceable to the full extent permitted
by law.

           Section 11. Notices. All notices hereunder, to be effective, shall be
in writing and shall be delivered by hand or mailed by certified mail, postage
and fees prepaid, as follows:

                    If to the Company:      Voicetek Corporation
                                            19 Alpha Road
                                            Chelmsford, MA  01824-4175
                                            Attn: President

                    Copy to:                Anthony J. Medaglia, Jr., Esq.
                                            HUTCHINS, WHEELER & DITTMAR
                                            A Professional Corporation
                                            101 Federal Street
                                            Boston, MA  02110

                    If to the Executive:    Daniel Poranski
                                            137 Linebrook Road
                                            Ipswich, MA  01938

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or to such other address as a party may notify the other pursuant to a notice
given in accordance with this Section 11.

           Section 12. Miscellaneous.

           Section 12.01. Modification. This Agreement constitutes the entire
Agreement between the parties hereto with regard to the subject matter hereof,
superseding all prior understandings and agreements, whether written or oral.
This Agreement may not be amended or revised except by a writing signed by the
parties.

           Section 12.02. Assignment and Transfer. This Agreement shall not be
terminated by the merger or consolidation of the Company with any corporate or
other entity or by the transfer of all or substantially all of the assets of the
Company to any other person, corporation, firm or entity. The provisions of this
Agreement shall be binding on and shall inure to the benefit of any such
successor in interest to the Company. Neither this Agreement nor any of the
rights, duties or obligations of the Executive shall be assignable by the
Executive, nor shall any of the payments required or permitted to be made to the
Executive by this Agreement be encumbered, transferred or in any way
anticipated.

           Section 12.03. Captions. Captions herein have been inserted solely
for convenience of reference and in no way define, limit or describe the scope
or substance of any provision of this Agreement.

           Section 12.04. Governing Law. This Agreement shall be construed under
and enforced in accordance with the laws of The Commonwealth of Massachusetts.

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           IN WITNESS WHEREOF, the parties hereto have duly executed this
Agreement as a sealed instrument as of the day and year first above written.


                                            VOICETEK



                                       By:_____________________________________
                                            President



                                            EXECUTIVE



                                       By:_____________________________________
                                            Name:

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