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                                                                   Exhibit 10.15


                           RESTRICTED STOCK AGREEMENT


NAME OF GRANTEE:              GLENDA DAVIS

NO. OF SHARES:                100,000

VESTING COMMENCEMENT DATE:    JANUARY 19, 2001

GRANT DATE:                   MARCH 13, 2001

PER SHARE PURCHASE PRICE:     $2.5312


     MCK Communications, Inc., a Delaware corporation (together with its
successors, the "COMPANY"), hereby grants, sells and issues to the person named
above (the "GRANTEE"), who is an officer, employee, director or Consultant of
the Company or any of its Subsidiaries, the number of shares of Common Stock,
par value $0.001 per share (together with any successor securities, including
stock of any successor corporation, "COMMON STOCK"), of the Company indicated
above (subject to the provisions below, the "SHARES"), for the per share
purchase price specified above, subject to the terms and conditions set forth
herein. The Grantee agrees to the provisions set forth herein and acknowledges
that each such provision is a material condition of the Company's agreement to
issue and sell the Shares to her. The Company hereby acknowledges receipt of TWO
HUNDRED FIFTY THREE THOUSAND ONE HUNDRED TWENTY DOLLARS AND NO CENTS
($253,120.00) in full payment for the Shares of which ONE HUNDRED DOLLARS AND NO
CENTS ($100.00) (representing the par value for the Shares) was paid to the
Company in cash. All references to share prices and amounts herein shall be
equitably adjusted to reflect stock splits, stock dividends, recapitalizations,
mergers, reorganizations and similar changes affecting the capital stock of the
Company, and any shares of capital stock of the Company received on or in
respect of Shares in connection with any such event (including any shares of
capital stock or any right, option or warrant to receive the same or any
security convertible into or exchangeable for any such shares or received upon
conversion of any such shares) shall be subject to this Agreement on the same
basis and extent at the relevant time as the Shares in respect of which they
were issued, and shall be deemed Shares as if and to the same extent they were
issued on the grant date as set forth above (the "GRANT DATE").

     1.   DEFINITIONS. For the purposes of this Agreement, the following terms
shall have the following respective meanings.

          "ACT" shall mean the Securities Act of 1933, as amended, and the rules
and regulations thereunder.

          "CAUSE" shall mean the determination by a majority of the Board of
Directors of the Company that are not employees of the Company that any one or
more of the following


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events has occurred: (A) dishonesty, breach of fiduciary duty or breach of the
terms of this Agreement or any other agreements executed by the Grantee; (B)
commission by the Grantee of any act of embezzlement, fraud, larceny or theft on
or from the Company; (C) substantial and continuing neglect or inattention by
the Grantee of duties of his employment which shall continue for 30 business
days following written notification by the Board of Directors; (D) willful
misconduct or gross negligence of the Grantee in connection with the performance
of such duties; (E) commission by the Grantee of any acts of moral turpitude;
(F) the conviction of the Grantee of a felony. A determination by the Board of
Directors, after notice to the Grantee and providing the Grantee an opportunity
to be heard, that the Grantee has committed an act of the sort mentioned in (A)
through (F) above shall be conclusive, whether or not there are proceedings by
public authorities with respect thereto and without regard to the outcome
thereof.

          "CONSULTANT" means a person engaged to provide consulting or advisory
services (other than as an employee or director) to the Company or its
Subsidiaries, provided that the identity of such person, the nature of such
services or the entity to which such services are provided would not preclude
the Company from offering or selling securities to such person pursuant to the
Plan in reliance on registration on a Form S-8 Registration Statement under the
Act.

          "GOOD REASON" shall mean the occurrence of any of the following
events: (i) a substantial adverse change in the nature or scope of the Grantee's
responsibilities, authorities, powers, functions or duties (other than changes
to reflect an integration of the Company into an acquiring entity in the event
of a Transaction); or (ii) a reduction in the Grantee's annual base salary or
bonus compensation (subject to applicable performance requirements with respect
to the actual amount of bonus compensation earned) except for across-the-board
reductions similarly affecting all, or substantially all, similar employees.

          "PERMITTED TRANSFEREES" shall mean any of the following to whom the
Grantee may transfer Shares hereunder: the Grantee's spouse, children (natural
or adopted), stepchildren or a trust for their sole benefit of which the Grantee
is the settlor; PROVIDED, HOWEVER, that any such trust does not require or
permit distribution of any Shares during the term of this Agreement unless
subject to its terms.

          "PERSON" shall mean any individual, corporation, partnership (limited
or general), limited liability company, limited liability partnership,
association, trust, joint venture, unincorporated organization or any similar
entity.

          "RESTRICTED SHARES" shall initially mean all of the Shares being
purchased by the Grantee on the Grant Date, PROVIDED that Shares shall become
Vested Shares with respect to 1/4th of the Shares on the first anniversary of
the Vesting Commencement Date and 1/48th of the Shares at the end of each full
calendar month thereafter. Notwithstanding the foregoing, Restricted Shares may
become Vested Shares in accordance with the provisions of Section 3(d).

          "SERVICE RELATIONSHIP" means the Grantee's employment or service with
the Company or its Subsidiary, whether in the capacity of an employee, director
or a Consultant.


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Unless otherwise determined by the Board of Directors, the Grantee's Service
Relationship shall not be deemed to have terminated merely because of a change
in the capacity in which the Grantee renders service to the Company or a
transfer between locations of the Company or its Subsidiaries or a transfer
between the Company and any Subsidiary, provided that there is no interruption
or other termination of the Service Relationship. The Board of Directors, in its
discretion, shall determine whether the Grantee's Service Relationship has
terminated and the effective date of such termination.

          "SUBSIDIARY" means any corporation (other than the Company) in any
unbroken chain of corporations beginning with the Company if each of the
corporations (other than the last corporation in the unbroken chain) owns stock
possessing fifty percent (50%) or more of the total combined voting power of all
classes of stock in one of the other corporations in the chain.

          "TERMINATION EVENT" shall mean the termination of the Grantee's
Service Relationship for any reason whatsoever, regardless of the circumstances
thereof, and including without limitation upon death, disability, retirement or
discharge or resignation for any reason, whether voluntary or involuntary. For
purposes hereof, the Board of Directors' determination of the reason for
termination of the Grantee's employment shall be conclusive and binding on the
Grantee and the Grantee's representatives or legatees.

          "TRANSACTION" shall mean (i) a merger, reorganization or consolidation
between the Company and another person or entity (other than a holding company
or Parent or Subsidiary of the Company) as a result of which the holders of the
Company's outstanding voting stock immediately prior to the transaction hold
less than a majority of the outstanding voting stock of the surviving entity
immediately after the transaction, (ii) the sale of all or substantially all of
the assets of the Company to an unrelated person or entity, or (iii) the direct
or indirect sale or exchange in a single or series of related transactions by
the stockholders of the Company of more than fifty percent (50%) of all of the
Stock of the Company to an unrelated person or entity as a result of which the
holders of the Company's outstanding voting stock immediately prior to the
transaction hold less than a majority of the outstanding voting stock of the
surviving entity immediately after the transaction.

          "VESTED SHARES" shall mean all Shares which are not Restricted Shares.

     2.   PURCHASE AND SALE OF SHARES; INVESTMENT REPRESENTATIONS.

          (a) PURCHASE AND SALE. On the date hereof, the Company hereby sells to
the Grantee, and the Grantee hereby purchases from the Company, the number of
Shares set forth above for the purchase price per share set forth above.

          (b) INVESTMENT REPRESENTATIONS. In connection with the purchase and
sale of the Shares contemplated by SECTION 2(a) above, the Grantee hereby
represents and warrants to the Company as follows:


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               (i) The Grantee is purchasing the Shares for the Grantee's own
account for investment only, and not for resale or with a view to the
distribution thereof.

               (ii) The Grantee has had such an opportunity as she has deemed
adequate to obtain from the Company such information as is necessary to permit
her to evaluate the merits and risks of the Grantee's investment in the Company
and has consulted with the Grantee's own advisers with respect to the Grantee's
investment in the Company.

               (iii) The Grantee has sufficient experience in business,
financial and investment matters to be able to evaluate the risks involved in
the purchase of the Shares and to make an informed investment decision with
respect to such purchase.

               (iv) The Grantee can afford a complete loss of the value of the
Shares and is able to bear the economic risk of holding such Shares for an
indefinite period.

               (v) The Grantee understands that the Shares are not registered
under the Act or any applicable state securities or "blue sky" laws and may not
be sold or otherwise transferred or disposed of in the absence of an effective
registration statement under the Act and under any applicable state securities
or "blue sky" laws (or exemptions from the registration requirements thereof).
The Grantee further acknowledges that certificates representing the Shares will
bear restrictive legends reflecting the foregoing.

     3.   REPURCHASE OF RESTRICTED SHARES.

          (a) REPURCHASE. Upon the occurrence of a Termination Event, the
Company or its assigns shall have the right and option to repurchase all or any
portion of the Restricted Shares held by the Grantee, any Permitted Transferee
or any other applicable person or entity as of the date of such Termination
Event at the per share purchase price set forth above, subject to adjustment as
provided above. The purchase and sale arrangements contemplated by the preceding
sentences of this SECTION 3 are referred to herein as the "REPURCHASE."

          (b) CLOSING PROCEDURE. The Company or its assigns shall effect the
Repurchase (if so elected) by delivering or mailing to the Grantee (and/or, if
applicable, any Permitted Transferees or any other applicable person or entity)
written notice within ninety (90) days after the Termination Event, specifying a
date within such ninety (90) day period in which the Repurchase shall be
effected. Upon such notification, the Grantee, any Permitted Transferees and/or
any other applicable person or entity shall promptly surrender to the Company
any certificates representing the Restricted Shares being purchased, together
with a duly executed stock power for the transfer of such Restricted Shares to
the Company or the Company's assignee or assignees (as contemplated by SECTION
6, if applicable). Upon the Company's or its assignee's receipt of the
certificates from the Grantee, any Permitted Transferees or any other applicable
person or entity, the Company or its assignee or assignees shall deliver to him,
her or them a check for the purchase price of the Restricted Shares being
purchased, PROVIDED, HOWEVER, that if such Restricted Shares are being purchased
from the Grantee, the Company may pay the purchase price for such shares by
offsetting and canceling any indebtedness then owed


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by the Grantee to the Company. At such time, the Grantee, any Permitted
Transferees and/or any holders of the Restricted Shares shall deliver to the
Company the certificate or certificates representing the Restricted Shares so
repurchased, duly endorsed for transfer, free and clear of any liens or
encumbrances. The Repurchase right specified herein shall survive and remain in
effect as to Restricted Shares following and notwithstanding any merger or other
transaction involving the Company and certificates representing such Restricted
Shares shall bear legends to such effect.

          (c) REMEDY. Without limitation of any other provision of this
Agreement or other rights, in the event that the Grantee, any Permitted
Transferees or any other applicable person or entity is required to sell the
Grantee's Restricted Shares pursuant to the provisions of this SECTION 3 and in
the further event that she refuses or for any reason fails to deliver to the
designated purchaser of such Restricted Shares the certificate or certificates
evidencing such Restricted Shares together with a related stock power, such
designated purchaser may deposit the purchase price for such Restricted Shares
with a bank designated by the Company, or with the Company's independent public
accounting firm, as agent or trustee, or in escrow, for the Grantee, any
Permitted Transferees or any other applicable person or entity, to be held by
such bank or accounting firm for the benefit of and for delivery to him, her,
them or it, and/or, in its discretion, pay such purchase price by offsetting any
indebtedness then owed by the Grantee as provided above. Upon any such deposit
and/or offset by the designated purchaser of such amount and upon notice to the
person or entity who was required to sell the Restricted Shares to be sold
pursuant to the provisions of this SECTION 3, such Restricted Shares shall at
such time be deemed to have been sold, assigned, transferred and conveyed to
such purchaser, the holder thereof shall have no further rights thereto (other
than the right to withdraw the payment thereof held in escrow, if applicable),
and the Company shall record such transfer in its stock transfer book or in any
appropriate manner.

          (d) SALE OF THE COMPANY. Upon and subject to the occurrence of a
Transaction in which the Company's assets or stock are acquired or exchanged for
consideration that consists solely of cash consideration or the dissolution or
liquidation of the Company, the Company shall have the right to acquire, on the
effective date of such Transaction, dissolution or liquidation and upon exercise
of such right, and the Grantee, any Permitted Transferees or any other
applicable person or entity shall sell to the Company or its assigns on the
effective date of such Transaction, dissolution or liquidation, some or all of
the Restricted Shares (after giving effect to any acceleration of vesting, if
any, arising as a result of such Transaction) held by the Grantee, any Permitted
Transferees or any other applicable person or entity as of such effective date
at a price per share equal to the per share purchase price set forth above,
subject to adjustment as provided in this Agreement. In the event of a
Transaction in which the Company's assets or stock are acquired or exchanged for
stock consideration, the provisions of this Agreement, including the Repurchase
provisions and the vesting schedule set forth herein, shall remain applicable to
the shares of such stock consideration received by the Grantee and any Permitted
Transferees; PROVIDED that if the Grantee's Service Relationship with such
successor entity is, on or within one (1) year after such Transaction, (i)
terminated by the successor entity without Cause, or (ii) terminated by the
Grantee for Good Reason, then one hundred percent (100%) of the Restricted
Shares shall become Vested Shares.


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     4.   RESTRICTIONS ON TRANSFER OF SHARES. None of the Shares now owned or
hereafter acquired shall be sold, assigned, transferred, pledged, hypothecated,
given away or in any other manner disposed of or encumbered, whether voluntarily
or by operation of law, unless such transfer is in compliance with all
applicable securities laws (including, without limitation, the Act), and such
disposition is in accordance with the terms and conditions of this SECTION 4. In
connection with any transfer of Shares, the Company may require the transferor
to provide at the Grantee's own expense an opinion of counsel to the transferor,
satisfactory to the Company, that such transfer is in compliance with all
foreign, federal and state securities laws (including, without limitation, the
Act). Any attempted disposition of Shares not in accordance with the terms and
conditions of this SECTION 4 shall be null and void, and the Company shall not
reflect on its records any change in record ownership of any Shares as a result
of any such disposition, shall otherwise refuse to recognize any such
disposition and shall not in any way give effect to any such disposition of any
Shares. Subject to the foregoing general provisions, the Grantee may sell,
assign, transfer or give away any or all of the Shares to Permitted Transferees;
PROVIDED, HOWEVER, that such Permitted Transferee(s) shall, as a condition to
any such transfer, agree to be subject to the provisions of this Agreement
(including, without limitation, the provisions of SECTION 3 and this SECTION 4)
and shall have delivered a written acknowledgment to that effect to the Company.

     5.   LEGEND. Any certificate(s) representing the Shares shall carry
substantially the following legend:

               "The transferability of this certificate and the shares of stock
          represented hereby are subject to the restrictions, terms and
          conditions (including repurchase and restrictions against transfers)
          contained in a certain Restricted Stock Agreement, as amended from
          time to time, between the Company and the holder of this certificate
          (a copy of which is available at the offices of the Company for
          examination)."

               "The shares represented by this certificate have not been
          registered under the Securities Act of 1933 or the securities laws of
          any state. The shares may not be sold or transferred in the absence of
          such registration or an exemption from registration."

     6.   ESCROW. In order to carry out the provisions of SECTIONS 3 and 4 of
this Agreement more effectively, the Company shall hold the Shares in escrow
together with separate stock powers executed by the Grantee in blank for
transfer, and any Permitted Transferee shall, as an additional condition to any
transfer of Shares, execute a like stock power as to such Shares. The Company
shall not dispose of the Shares except as otherwise provided in this Agreement.
In the event of any Repurchase, the Company is hereby authorized by the Grantee
and any Permitted Transferee, as the Grantee's and each such Permitted
Transferee's attorney-in-fact, to date and complete the stock powers necessary
for the transfer of the Shares being purchased and to transfer such Shares in
accordance with the terms hereof. At such time as any Shares are no


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longer Restricted Shares, the Company shall, at the written request of the
Grantee, Permitted Transferee or other applicable person or entity, deliver to
the Grantee (or the relevant Permitted Transferee or other applicable person or
entity) a certificate representing such Shares with the balance of the Shares to
be held in escrow pursuant to this SECTION 6.

     7.   WITHHOLDING TAXES. The Grantee acknowledges and agrees that the
Company or any of its Subsidiaries have the right to deduct from payments of any
kind otherwise due to the Grantee, or from the Shares held pursuant to SECTION 6
hereof, any federal, state or local taxes of any kind required by law to be
withheld with respect to the purchase of the Shares by the Grantee. In
furtherance of the foregoing the Grantee agrees to elect, in accordance with
Section 83(b) of the Internal Revenue Code of 1986, as amended, to recognize
ordinary income in the year of acquisition of the Shares, and to pay to the
Company all withholding taxes shown as due on his or her Section 83(b) election
form, or otherwise ultimately determined to be due with respect to such
election, based on the excess, if any, of the fair market value of such Shares
as of the date of the purchase of such Shares by the Grantee over the purchase
price for such Shares.

     8.   ASSIGNMENT. At the discretion of the Board of Directors of the
Company, the Company shall have the right to assign the right to exercise its
rights with respect to the Repurchase to any Person or Persons, in whole or in
part in any particular instance, upon the same terms and conditions applicable
to the exercise thereof by the Company, and such assignee or assignees of the
Company shall then take and hold any Shares so acquired subject to such terms as
may be specified by the Company in connection with any such assignment.

     9.   REGISTRATIONS RIGHTS.

          (a) PIGGYBACK REGISTRATIONS. Whenever the Company proposes to register
any of its securities under the Securities Act (except for registration
statements on Forms S-4 and S-8) and the registration form to be used may be
used for the registration of shares of the Company's Common Stock held by the
Grantee ("REGISTRABLE SECURITIES") (a "PIGGYBACK REGISTRATION"), the Company
shall give prompt written notice to Grantee of its intention to effect such a
registration and shall include in such registration all Registrable Securities
with respect to which the Company has received written requests for inclusion
therein within 20 days after the receipt of the Company's notice.

          (b) PIGGYBACK EXPENSES. All registration expenses of the Grantee
incurred in connection with a Piggyback Registration shall be paid by the
Company.

          (c) PRIORITY ON PRIMARY REGISTRATION. If a Piggyback Registration is
an underwritten registration, and the managing underwriters advise the Company
in writing that in their opinion the number of securities requested to be
included in such registration exceeds the number which can be sold in such
offering without adversely affecting the marketability of the offering, the
Company shall include in such registration (i) first, the securities the Company
proposes to sell, (ii) second, the securities requested to be included in such
registration by the stockholder(s) requesting such registration, (iii) third,
Registrable Securities held by the Grantee and (iv) fourth, all other securities
requested to be included in such registration.


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     10.  MISCELLANEOUS PROVISIONS.

          (a) RECORD OWNER; DIVIDENDS. The Grantee and any Permitted
Transferees, or other applicable person or entity during the duration of this
Agreement, shall be considered the record owners of and shall be entitled to
vote the Shares. The Grantee and any Permitted Transferees or other applicable
person or entity shall be entitled to receive all dividends and any other
distributions declared on the Shares; PROVIDED, HOWEVER, that the Company is
under no duty to declare any such dividends or to make any such distribution.

          (b) EQUITABLE RELIEF. The parties hereto agree and declare that legal
remedies are inadequate to enforce the provisions of this Agreement and that
equitable relief, including specific performance and injunctive relief, may be
used to enforce the provisions of this Agreement.

          (c) CHANGE AND MODIFICATIONS. This Agreement may not be orally
changed, modified or terminated, nor shall any oral waiver of any of its terms
be effective. This Agreement may be changed, modified or terminated only by an
agreement in writing signed by the Company and the Grantee.

          (d) GOVERNING LAW. This Agreement shall be governed by and construed
in accordance with the laws of the State of Delaware without regard to conflict
of laws principles.

          (e) HEADINGS. The headings are intended only for convenience in
finding the subject matter and do not constitute part of the text of this
Agreement and shall not be considered in the interpretation of this Agreement.

          (f) SAVING CLAUSE. If any provision(s) of this Agreement shall be
determined to be illegal or unenforceable, such determination shall in no manner
affect the legality or enforceability of any other provision hereof.

          (g) NOTICES. All notices, requests, consents and other communications
shall be in writing and be deemed given when delivered personally, by telex or
facsimile transmission or when received if mailed by first class registered or
certified mail, postage prepaid. Notices to the Company or the Grantee shall be
addressed as set forth underneath their signatures below, or to such other
address or addresses as may have been furnished by such party in writing to the
other. Notices to any holder of the Shares other than the Grantee shall be
addressed to the address furnished by such holder to the Company.

          (h) BENEFIT AND BINDING EFFECT. This Agreement shall be binding upon
and shall inure to the benefit of the parties hereto, their respective
successors, assigns, and legal representatives. Without limitation of the
foregoing, upon any stock-for-stock merger in which the Company is not the
surviving entity, shares of the Company's successor issued in respect of the
Shares shall remain subject to vesting and the Repurchase hereunder. The Company
has the right to assign this Agreement, and such assignee shall become entitled
to all the rights of the Company hereunder to the extent of such assignment.


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          (i) EMPLOYMENT. This Agreement does not confer upon the Grantee any
right to continued employment or service with the Company or any Subsidiary, or
interfere in any way with the right of the Company or its Subsidiary to
terminate the Grantee's employment or service at any time.

          (j) COUNTERPARTS. For the convenience of the parties and to facilitate
execution, this Agreement may be executed in two or more counterparts, each of
which shall be deemed an original, but all of which shall constitute one and the
same document.


                            [Signature page follows]


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     IN WITNESS WHEREOF, the Company and the Grantee have executed this
Restricted Stock Agreement as of the date first above written.

                                        COMPANY:

                                        MCK COMMUNICATIONS, INC.


                                        By: /s/ Paul K. Zurlo
                                            ------------------------------------
                                            Name: Paul K. Zurlo
                                            Title: Chief Financial Officer


                                        GRANTEE:


                                        /s/ Glenda Davis
                                        ----------------------------------------
                                        Glenda Davis

                                        Address:

                                        c/o MCK Communications, Inc.
                                        117 Kendrick Street
                                        Needham, MA 02494