<PAGE>

                                                                    EXHIBIT 10.9

                         REGISTRATION RIGHTS AGREEMENT

    AGREEMENT, made as of the 31st day of March, 1999 by and between Be Free,
Inc., (f/k/a Freedom of Information, Inc.), a Delaware corporation (the
"Company") and those persons identified on the signature pages hereto as an
"Investor" (each an "Investor" and collectively, the "Investors").

    WHEREAS, the Investors are entering into a Series B Convertible Preferred
Stock Purchase Agreement of even date with the Company (the "Purchase
Agreement"), pursuant to which the Investors are acquiring shares of Series B
Convertible Participating Preferred Stock (the "Preferred Stock"); and

    WHEREAS, the execution of this Agreement by the Company is a condition
precedent to the obligations of the Investors to perform their obligations under
the Purchase Agreement.

    NOW, THEREFORE, in consideration of the premises and mutual covenants
contained herein, the parties hereto agree as follows:

    1.  Certain Definitions.  As used in this Agreement, the following terms
shall have the following respective meanings:

    "Act" means the Securities Act of 1933, as amended, or any successor federal
statute, and the rules and regulations of the Commission thereunder, all as the
same shall be in effect at the time.

    "Commission" means the Securities and Exchange Commission, or any other
Federal agency at the time administering the Act.

    "Company" means Be Free, Inc., a Delaware corporation, and its successors
and assigns.

    "Exchange Act" means the Securities Exchange Act of 1934, as amended, or any
successor federal statute, and the rules and regulations of the Commission
thereunder, all as the same shall be in effect at the time.

    "Holder" means the person who is then the record owner of Registrable
Securities which have not been sold to the public.


    "Registrable Securities" means (i) all shares of Common Stock now owned or
hereafter acquired by an Investor, including any shares of Preferred Stock which
are to be (but have not yet been) converted into Common Stock in connection with
the consummation of a
<PAGE>

registration hereunder; and (ii) any Common Stock issued in respect of the
shares described in clause (i) upon any stock split, stock dividend,
recapitalization or other similar event.

    The term "register" means to register under the Act and applicable state
securities laws for the purpose of effecting a public sale of securities.

    2.  Requested Registrations

        (a) Demand.  At any time after the earlier of June 30, 2001 or 180 days
after the effective date of the Company's first registration statement under the
Securities Act for an offering with proceeds of at least Two Million Five
Hundred Thousand Dollars ($2,500,000) (an "Initial Public Offering"), one or
more Investors may request in writing that the Company effect the registration
of Registrable Securities representing at least thirty-three and one-third
percent (33 1/3%) of the Registrable Securities held by the Investors (or any
lesser percentage if the reasonably anticipated aggregate price to the public of
the Registrable Securities to be included in such registration would exceed
$5,000,000).

        (b) Form S-3.  After an Initial Public Offering, the Company shall use
its reasonable best efforts to qualify and remain qualified to register
securities on Form S-3 (or any successor form) under the Act.  Any Holder or
Holders shall have the right to request registrations for an offering with
proceeds of at least One Million Dollars ($1,000,000) on Form S-3 (or any
successor form) for the Registrable Securities held by such requesting Holder,
including registrations for the sale of such Registrable Securities on a delayed
or continuous basis pursuant to Rule 415 under the Act.  Such requests shall be
in writing and shall state the number of shares of Registrable Securities to be
disposed of and the intended method of disposition of such shares by such Holder
or Holders.

        (c) In the case of a requested registration under this Section 2, the
Company will:

            (i)    promptly give written notice of the proposed registration to
    all other Holders; and

            (ii)   as soon as practicable, use its best efforts to cause such
    Registrable Securities specified in such a request (together with such
    portion of the Registrable Securities of any Holder or Holders joining in
    such request pursuant to Section 3 as are specified in a written request
    given within ten (10) days after receipt of such written notice from the
    Company) to be registered as soon as practicable so as to permit the sale
    thereof and in connection therewith prepare and file a registration
    statement on Form S-1 under the Securities Act (or on such other form as may
    be appropriate) to effect such registration and seek to have such
    registration statement become effective as promptly as practicable;
    provided, however, that such request shall (i) specify the

                                      -2-
<PAGE>

    number of Registrable Securities intended to be offered and sold, (ii)
    express the present intention of the Holders to offer or cause the offering
    of such Registrable Securities for distribution, (iii) describe the nature
    or method of the proposed offer and sale thereof, and (iv) contain the
    undertaking of the Holders to provide all such information and materials and
    take all such action as may be reasonably required in order to permit the
    Company to comply with all applicable requirements of the Commission and to
    obtain any desired acceleration of the effective date of such registration
    statement. Upon any registration becoming effective pursuant to this Section
    2(a), the Company shall use reasonable efforts to keep such registration
    statement current for a period of 90 days.

        (d) Limit on Requested Registrations.  The obligation of the Company to
register any Registrable Securities on demand by the Investors under Section 2
hereof shall continue only until the Company has effected two (2) demand
registrations on behalf of the Holders pursuant to this Section 2(a) and 2(b);
provided, however, no registration initiated hereunder shall count as a
registration initiated hereunder unless and until it shall have been
consummated.

        (e) Selection of Underwriter.  The underwriter of any underwriting
requested under this Section 2 that is not on Form S-1 shall be selected by the
Holders, holding a majority of the Registrable Securities included therein;
provided that such underwriter must be reasonably acceptable to the Company with
the Company specifying in writing the reasons for any rejection of an
underwriter selected by the Holders.  The Company shall select the underwriter
for any registration effected on Form S-1.

    3.  "Piggy Back" Registrations.

        (a) The rights contained in this Section 3 shall be in addition to the
rights provided in Section 2 hereof.  If the Company shall determine to register
any of its securities, either for its own account or the account of a security
holder or holders exercising their registration rights (subject to the
provisions of Section 2), other than a registration relating solely to employee
benefit plans or a registration on any registration form which does not permit
secondary sales or does not include substantially the same information as would
be required to be included in a registration statement covering the sale of
shares or pursuant to Form S-4, the Company will:

            (i)    Promptly give to each Holder of Registrable Securities
    written notice thereof (which shall include the number of shares the Company
    or other security holder proposes to register and, if known, the name of the
    proposed underwriter); and

            (ii)   Use its best efforts to include in such registration all the
    Registrable Securities specified in a written request or requests, made by
    any Holder within ten (10) days after the date of delivery of the written
    notice from the Company described in

                                      -3-
<PAGE>

    clause (i) above. If in the good faith judgment of the managing underwriter
    of such public offering, the inclusion of all or any portion of the shares
    held by the Holders originally included in a request for registration would
    reduce the number of shares to be offered by the Company (or by another
    holder of shares that initiated the offering by exercising rights to demand
    such registration) or interfere with the successful marketing of the
    securities offered by the Company (or by such other holder that initiated
    the offering (the "Initiating Holder")), the number of shares otherwise to
    be included by the Holders in the underwritten public offering may be
    reduced pro rata or excluded altogether; provided, however, that (A) in any
    such offering by the Company, the shares to be included by the Holders may
    be excluded altogether but must be treated in the same manner as all other
    selling security holders, and (B) in any such offering initiated by an
    Initiating Holder, the shares otherwise to be included by the Holders (other
    than the Initiating Holder) shall be allocated pro rata based on the number
    of Registrable Securities each such Holder owns to the number of shares of
    Common Stock (and shares convertible into Common Stock) owned by all other
    holders having contractual piggyback registration rights and requesting
    inclusion in such registration, and can be excluded altogether but shall be
    treated in the same manner as all selling security holders (other than the
    Initiating Holder).

        (b) The Company shall select the underwriter for an offering made
pursuant to this Section 3.

    4.  Expenses.  The Company shall pay all out-of-pocket costs in connection
with any registration pursuant to this Agreement.  The costs and expenses of any
such registration shall include, without limitation, the fees and expenses of
the Company's counsel and its accountants and all other out-of-pocket costs and
expenses of the Company incident to the preparation, printing and filing under
the Securities Act of the registration statement and all amendments and
supplements thereto and the cost of furnishing copies of each preliminary
prospectus, each final prospectus and each amendment or supplement thereto to
underwriters, dealers and other purchasers of the securities so registered, the
costs and expenses incurred in connection with the qualification of such
securities so registered under the "blue sky" laws of various jurisdictions, the
fees and expenses of the Company's transfer agent, the reasonable fees and
expenses of one counsel for the Investors, expenses of all marketing and
promotional efforts requested by the managing underwriter and all other costs
and expenses of complying with the foregoing provisions hereof with respect to
such registration.  The Holders shall bear underwriting discounts, selling
commissions and transfer taxes with respect to the shares sold by them pursuant
to the registration.

    5.  Registration Procedures.  In the case of each registration effected by
the Company pursuant to this Agreement, the Company will keep each Holder of
Registrable Securities included in such registration advised in writing as to
the initiation of each

                                      -4-
<PAGE>

registration and as to the completion thereof. At its expense, the Company will
do the following for the benefit of such Holders:

        (a) Keep such registration effective for a period of 90 days or until
the Holder or Holders have completed the distribution described in the
registration statement relating thereto, whichever first occurs, and amend or
supplement such registration statement and the prospectus contained therein from
time to time to the extent necessary to comply with the Act and applicable state
securities laws.  If at any time the Commission should institute or threaten to
institute any proceedings for the purpose of issuing, or should issue a stop
order suspending the effectiveness of any such registration statement, the
Company will promptly notify the Holder and will use reasonable efforts to
prevent the issuance of any such stop order or to obtain the withdrawal thereof
as soon as possible;

        (b) Use its best efforts to register or qualify the Registrable
Securities covered by such registration under the applicable securities or "blue
sky" laws of such jurisdictions as the selling shareholders may reasonably
request; provided, that the Company shall not be obligated to qualify to do
business in any jurisdiction where it is not then so qualified or otherwise
required to be so qualified or to take any action which would subject it to the
service of process in suits other than those arising out of such registration;

        (c) Furnish such number of prospectuses and other documents incident
thereto as a Holder or the underwriter from time to time may reasonably request;

        (d) In connection with any underwritten offering pursuant to a
registration statement filed pursuant to Section 2 hereof, the Company will
enter into any underwriting agreement reasonably necessary to effect the offer
and sale of Common Stock, provided such underwriting agreement contains
customary underwriting provisions and is entered into by the Holder and provided
further that, if the underwriter so requests, the underwriting agreement will
contain customary contribution provisions on the part of the Company;

        (e) To the extent then permitted under applicable professional
guidelines and standards, use its best efforts to obtain a comfort letter from
the Company's independent public accountants in customary form and covering such
matters of the type customarily covered by comfort letters and an opinion from
the Company's counsel in customary form and covering such matters of the type
customarily covered in a public issuance of securities, in each case addressed
to the Holders, and provide copies thereof to the Holders; and

        (f) Permit the counsel to the Holders whose expenses are being paid
pursuant to Section 4 hereof to inspect and copy such corporate documents as he
may reasonably request.

    6.  Indemnification.

                                      -5-
<PAGE>

        (a) The Company will, and hereby does, indemnify and hold harmless each
Holder, each of its officers, directors and partners, and each person
controlling such Holder within the meaning of the Act, with respect to which
registration, qualification or compliance has been effected pursuant to this
Agreement, and each underwriter, if any, and each person who controls such
underwriter within the meaning of the Act, against all claims, losses, damages
and liabilities (or actions in respect thereof) arising out of or based on any
untrue statement (or alleged untrue statement) of a material fact contained in
any prospectus, offering circular or other document (including any related
registration statement, notification or the like) incident to any such
registration, qualification or compliance, or based on any omission (or alleged
omission) to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, or any violation by the
Company of the Act or the Exchange Act or securities act of any state or any
rule or regulation thereunder applicable to the Company and relating to action
or inaction required of the Company in connection with any such registration,
qualification or compliance, and will reimburse each such Holder, each of its
officers, directors and partners, and each person controlling such Holder, each
such underwriter and each person who controls any such underwriter, for any
legal and any other expenses reasonably incurred in connection with
investigating and defending any such claim, loss, damage, liability or action,
whether or not resulting in any liability; provided that the Company will not be
liable in any such case to the extent that any such claim, loss, damage,
liability or expense arises out of or is (x) based upon any such untrue
statement or omission or alleged untrue statement or omission made in reliance
upon information furnished in writing to the Company by the Holders or any
underwriter or any controlling person of the Holders or any such underwriter
specifically for use therein, or (y) made in any preliminary prospectus, if the
prospectus contained in the registration statement as declared effective or in
the form filed by the Company with the Commission pursuant to Rule 424 under the
Securities Act shall have corrected such statement or omission, ample copies of
such prospectus (together with a statement that such corrected prospectus must
be used in lieu of all prior prospectuses) shall have been provided by the
Company to the Holders or underwriter, and a copy of such prospectus shall not
have been sent or otherwise delivered to such person by the Holders or
underwriter at or prior to the confirmation of such sale to such person.

        (b)  By requesting registration under this Agreement each Holder shall
agree in the same manner and to the same extent as set forth in the preceding
paragraph, to indemnify and to hold harmless the Company and its directors and
officers and each person, if any, who controls the Company within the meaning of
the Securities Act and any underwriter (as defined in the Securities Act) of any
shares offered by the Holders, against any such claim, loss, damage, liability
or expense, joint or several, to which any of such persons may be subject under
the Securities Act or otherwise, and to reimburse any of such persons for any
legal or other expenses reasonably incurred by them in connection with
investigating or defending against any such claim, loss, damage, liability or
expense, but only to the extent it arises out of or is based upon an untrue
statement or alleged untrue statement

                                      -6-
<PAGE>

or omission or alleged omission of a material fact in any registration statement
under which the Holders' registered under the Securities Act pursuant to this
Agreement, any prospectus contained therein, or any amendment or supplement
thereto, which was based upon and made in conformity with information furnished
in writing to the Company by the Holders or such underwriter expressly for use
therein; provided however, that the obligations of each Holder hereunder shall
be limited to an amount equal to the lesser of (i) net proceeds received by such
Holder upon the sales of the securities and (ii) such Holder's pro rata share of
such claim, loss, damage, liability or expense.

        (c) Each party entitled to indemnification under this Section 6 (the
"Indemnified Party") shall give notice to the party required to provide
indemnification (the "Indemnifying Party") promptly after such Indemnified Party
has actual knowledge of any claim as to which indemnity may be sought.  The
failure of any Indemnified Party to give such notice shall not relieve the
Indemnifying Party of its obligations under this Section 6, except and to the
extent the Indemnifying Party has been prejudiced as a consequence thereof and
in no event shall such failure relieve the underlying party from any other
liability which it may have to such indemnified party.  The Indemnifying Party
will be entitled to participate in, and to the extent that it may elect by
written notice delivered to the Indemnified Party promptly after receiving the
aforesaid notice from such Indemnified Party, at its expense to assume, the
defense of any such claim or any litigation resulting therefrom (including
control over any settlement thereof), with counsel reasonably satisfactory to
such Indemnified Party, provided that the Indemnified Party may participate in
such defense at its expense, notwithstanding the assumption of such defense by
the Indemnifying Party, and provided, further, that if the defendants in any
such action shall include both the Indemnified Party and the Indemnifying Party
and the Indemnified Party shall have reasonably concluded that there may be
legal defenses available to it and/or other Indemnified Parties which are
different from or additional to those available to the Indemnifying Party, the
Indemnified Party or Parties shall have the right to select separate counsel to
assert such legal defenses and to otherwise participate in the defense of such
action on behalf of such Indemnified Party or Parties and the fees and expenses
of such counsel shall be paid by the Indemnifying Party.  No Indemnifying Party,
in the defense of any such claim or litigation, shall, except with the consent
of each Indemnified Party, consent to entry of any judgment or enter into any
settlement which does not include as an unconditional term thereof the giving by
the claimant or plaintiff to such Indemnified Party of a release from all
liability in respect to such claim or litigation.  Each Indemnified Party shall
(i) furnish such information regarding itself or the claim in question as an
Indemnifying Party may reasonably request in writing and as shall be reasonably
required in connection with defense of such claim and litigation resulting
therefrom and (ii) shall reasonably assist the Indemnifying Party in any such
defense, provided that the Indemnified Party shall not be required to expend its
funds in connection with such assistance.

                                      -7-
<PAGE>

        (d) No Holder shall be required to participate in a registration
pursuant to which it would be required to execute an underwriting agreement in
connection with a registration effected under Section 2 or 3 which imposes
indemnification or contribution obligations on such Holder more onerous than
those imposed hereunder; provided, however, that the Company shall not be deemed
to breach the provisions of Section 2 or 3 if a Holder is not permitted to
participate in a registration on account of his refusal to execute an
underwriting agreement on the basis of this subsection (d).

    7.  Lock-up Agreement.  If requested by the underwriter in any registered
public offering by the Company, each Holder agrees not to sell or otherwise
transfer any Registrable Securities for such period of time after the date of
such offering as may be requested by the underwriter, but in no event to exceed
180 days from the close of the initial registered public offering and 90 days
from the close of any subsequent registered public offering, provided that all
executive officers and directors of the Company enter into similar agreements.

    8.  Information by Holder.  Each Holder of Registrable Securities included
in any registration shall furnish to the Company such information regarding such
Holder and the distribution proposed by such Holder as the Company may
reasonably request in writing and as shall be reasonably required in connection
with any registration, qualification or compliance referred to in this Agreement
or otherwise required by applicable state or federal securities laws.

    9.  Limitations on Registration Rights.  From and after the date of this
Agreement, the Company shall not, without the prior written consent of the
holders of a majority in interest of the Preferred Stock or Conversion Shares,
enter into any agreement with any holder or prospective holder of any securities
of the Company which would give any such holder or prospective holder (a) the
right to require the Company, upon any registration of any of its securities, to
include, among the securities which the Company is then registering, securities
owned by such holder, unless under the terms of such agreement, Holders of
Registrable Shares shall be entitled to include Registrable Shares in such
registration statement on terms no less favorable to the Holder of Registrable
Shares than those provided to such holder or prospective holder hereunder; or
(b) the right to require the Company to initiate any registration of any
securities of the Company prior to January 1, 2002 or 360 days after the
effective date of the Company's Initial Public Offering.

    10. Exception to Registration.  The Company shall not be required to effect
a registration under this Agreement if (i) in the written opinion of counsel for
the Company, which counsel and the opinion so rendered shall be reasonably
acceptable to the Holders of Registrable Securities, such Holders may sell
without registration under the Act all Registrable Securities for which they
requested registration under the provisions of the Act, or (ii) the Company
shall have obtained from the Commission a "no-action" letter to that effect;
provided that this Section 10 shall not apply to sales made under Rule 144(k) or
any

                                      -8-
<PAGE>

successor rule promulgated by the Commission until after the effective date of
the Company's initial registration of shares under the Act. Notwithstanding the
foregoing, in no event shall the provisions of this Section 10 be construed to
preclude a Holder of Registrable Securities from exercising rights under Section
3 for a period of three years after the effective date of the Company's initial
registration of shares under the Act.

    11.  Rule 144 Reporting.  With a view to making available the benefits of
certain rules and regulations of the Commission which may permit the sale of
restricted securities (as that term is used in Rule 144 under the Act) to the
public without registration, the Company agrees to:

         (a) make and keep public information available as those terms are
understood and defined in Rule 144 under the Act, at all times from and after
ninety days following the effective date of the first registration under the Act
filed by the Company for an offering of its securities to the general public;

         (b) use its best efforts to file with the Commission in a timely manner
all reports and other documents required of the Company under the Act and the
Exchange Act at any time after it has become subject to such reporting
requirements; and

         (c) so long as an Investor owns any restricted securities, furnish to
the Investor forthwith upon request a written statement by the Company as to its
compliance with the reporting requirements of Rule 144 (at any time from and
after ninety days following the effective date of the first registration
statement filed by the Company for an offering of its securities to the general
public), and of the Act and Exchange Act (at any time after it has become
subject to such reporting requirements), a copy of the most recent annual or
quarterly report of the Company, and such other reports and documents so filed
by the Company as an Investor may reasonably request in availing itself of any
rule or regulation of the Commission allowing an Investor to sell any such
securities without registration.

    12.  Damages.  The Company recognizes and agrees that the Holders of
Registrable Securities shall not have an adequate remedy if the Company fails to
comply with the provisions of this Agreement, and that damages will not be
readily ascertainable, and the Company expressly agrees that in the event of
such failure any Holder of Registrable Securities shall be entitled to seek
specific performance of the Company's obligations hereunder and that the Company
will not oppose an application seeking such specific performance.

    13.  Miscellaneous.

         (a) All covenants and agreements contained in this Agreement by or on
behalf of any of the parties hereto shall bind and inure to the benefit of the
respective

                                      -9-
<PAGE>

successors and assigns of the parties hereto (including without limitation
transferees of Registrable Securities as set forth in this Section 13(a)),
whether so expressed or not. The registration rights herein may be assigned (i)
in connection with any transaction or series of related transactions involving
the transfer or assignment to one or more transferees of at least 500,000 shares
of capital stock of the Company, other than pursuant to an effective
registration statement under the Securities Act or pursuant to Rule 144
thereunder (subject to adjustments for stock splits, stock dividends and the
like and aggregating all contemporaneous transfers by Holders), or (ii) to any
of the limited partners of a Holder that is a partnership, and upon any such
transfer such transferee shall be deemed to be included within the definition of
a "Holder".

         (b) All notices, requests, consents and other communications hereunder
shall be in writing and shall be mailed by certified or registered mail, return
receipt requested, postage prepaid, or telecopied or sent by other facsimile
method addressed as follows:

         If to the Company, or an Investor, at the address of such party set
    forth on Schedule I hereto or the most recent address as is shown on the
    stock records of the Company; and

         If to any subsequent Holder of Registrable Securities, to it at such
    address as may have been furnished to the Company in writing by such Holder;
    or, in any case, at such other address or addresses as shall have been
    furnished in writing to the Company (in the case of a Holder of Registrable
    Securities) or to the Holders of Registrable Securities (in the case of the
    Company) in accordance with the provisions of this paragraph.

         (c) This Agreement shall be governed by and construed in accordance
with the laws of the state of incorporation of Company, without giving effect to
the conflicts of laws principles thereof.

         (d) This Agreement may not be amended or modified, and no provision
hereof may be waived, without the written consent of the Company and the holders
of a majority in interest of the then outstanding shares held by the Investors.

         (e) This Agreement may be executed in two or more counterparts, each of
which shall be deemed an original, but all of which together shall constitute
one and the same instrument.

                                      -10-
<PAGE>

         (f) If any provision of this Agreement shall be held to be illegal,
invalid or unenforceable, such illegality, invalidity or unenforceability shall
attach only to such provision and shall not in any manner affect or render
illegal, invalid or unenforceable any other provision of this Agreement, and
this Agreement shall be carried out as if any such illegal, invalid or
unenforceable provision were not contained herein.

           [THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK]

                                      -11-
<PAGE>

    IN WITNESS WHEREOF, this Agreement has been executed by duly authorized
representation of each of the signatories hereto as of the date and year first
above written.


                              BE FREE, INC.


                              By: /s/ Stephen M. Joseph
                                  -------------------------------------
                                  Name: Stephen M. Joseph
                                  Title:   CFO


                              INVESTORS

                              HIGHLAND CAPITAL PARTNERS IV
                              LIMITED PARTNERSHIP

                              By:  Highland Management Partners IV, LLC,
                                  Its General Partner

                              By: /s/ illegible
                                  -------------------------------------
                                  Member

                              HIGHLAND ENTREPRENEURS' FUND IV
                              LIMITED PARTNERSHIP

                              By:  HIGHLAND ENTREPRENEURS'
                                   FUND IV, LLC, Its General Partner

                              By:  /s/ illegible
                                  -------------------------------------
                                  Member

                                      -12-
<PAGE>

                              COMDISCO, INC

                              By:  /s/ James Labe
                                  -------------------------------------
                                  Name: James Labe, President
                                  Title:   Comdisco Venture Division

                              THOMSON U.S. INC.


                              By:  /s/ James R. Schurr
                                  -------------------------------------
                                  Name:  James R. Schurr
                                  Title:  Vice President


                                  /s/ Josh M. Holden
                                  -------------------------------------
                                  Josh M. Holden, individually


                                  /s/Stephen Maysonave
                                  -------------------------------------
                                  Stephen Maysonave, individually


                                  /s/Daniel Rimer
                                  -------------------------------------
                                  Daniel Rimer, individually


                                  /s/ David Cowan
                                  -------------------------------------
                                  David Cowan, individually


                                  /s/ Thomas Paul
                                  -------------------------------------
                                  Thomas Paul, individually

                                      -13-
<PAGE>

                                  MATRIX PARTNERS V, L.P.

                                  By:  Matrix V Management Co, L.L.C., its
                                       General Partner

                                  By:  /s/ W. Michael Humphreys
                                       --------------------------------
                                       W. Michael Humphreys
                                       Managing Member


                              CHARLES RIVER PARTNERSHIP VIII,
                              A LIMITED PARTNERSHIP

                              By: Charles River VIII GP Limited Partnership,
                                  its General Partner


                              By:  /s/ Ted R. Dintersmith
                                  -------------------------------------
                                  Ted R. Dintersmith
                                  General Partner

                              CHARLES RIVER VIII-A LLC

                              By: Charles River Friends VII, Inc.,
                                  its Manager


                              By:  /s/ Ted R. Dintersmith
                                  -------------------------------------
                                  Ted R. Dintersmith
                                  Vice President

                                  MATRIX V ENTREPRENEURS FUND, L.P.

                                  By: Matrix V Management Co, L.L.C., its
                                       General Partner

                                  By: /s/ W. Michael Humphreys
                                       ---------------------------------
                                       W. Michael Humphreys
                                       Managing Member
<PAGE>

                                  DBV INVESTMENTS, L.P.

                                  By: DRT Capital, LLC, its General Partner


                                  By:  /s/ John Phelan
                                      ---------------------------------
                                      John Phelan,
                                      Manager

                                      /s/ Manuel Henriquez
                                      ---------------------------------
                                      Manuel Henriquez

                                      /s/ James Labe
                                      ---------------------------------
                                      Two Loons Trust