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                                                                     EXHIBIT 4.2


           SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT

        This Second Amended and Restated Registration Rights Agreement (the
"Agreement") is made and entered into as of December 8, 1999 between ATG GROUP,
INC. a Delaware corporation (the "Company"), and those persons listed on
Schedule 1 hereto (such persons, together with Affiliates thereof that hold
Registrable Securities are referred to as the "Investors").

        WHEREAS, those Investors holding Series A Preferred Stock, Series B
Preferred Stock and Series C Preferred Stock and the Founder Investors
(collectively, the "Prior Investors") entered into a Registration Rights
Agreement with the Company, dated July 30, 1999 (the "Prior Agreement");

        WHEREAS, the Company is selling shares of its Series D Preferred Stock
to certain purchasers (the "Series D Purchasers");

        WHEREAS, in order to induce the Series D Purchasers to purchase the
Series D Preferred Stock, the Investors and the Company have agreed to provide
for the registration rights set forth in this Agreement;

        WHEREAS, the Company and the Investors desire to amend and restate the
Prior Agreement, as amended by the Amendment, to read in its entirety as set
forth in this Agreement.

        NOW, THEREFORE, the parties to this Agreement hereby agree as follows:

        Unless otherwise defined herein, capitalized terms so used herein and
not defined shall have the same meaning as provided in the Purchase Agreement.

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

               "Commission" means the Securities and Exchange Commission.

               "Commission Form S-3" has the meaning specified in Section 2(a)
of this Agreement.

               "Common Stock" means the Common Stock, par value $.0001 per
share, of the Company, as constituted on the date hereof, any shares of the
Company's capital stock into which such Common Stock shall be changed, or any
shares of the Company's capital stock resulting from any reclassification of
such Common Stock or recapitalization of the Company.

               "Conversion Stock" means the Common Stock issued or issuable
pursuant to the conversion of the Convertible Preferred Stock.

               "Convertible Preferred Stock" means the Series A Preferred Stock,
Series B Preferred Stock, Series C Preferred Stock and Series D Preferred Stock.



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

               "Founder Investors" means Clifford G. Rudolph, Michael Black and
Curtis Wheeling and a "Founder Investor" means any one of them.

               "Founder Stock" means the Common Stock held by the Founder
Investors and the Rudolph Family 1997 Trust dated 10/10/97.

               "Incidental Registration" has the meaning specified in Section
2(b) of this Agreement.

               "Indemnified Parties" has the meaning specified in Section 6(a)
of this Agreement.

               "Indemnifying Party" has the meaning specified in Section 6(c) of
this Agreement.

               "Investors" means the Investors referred to in the Preamble and
any other person holding Registrable Securities to whom these registration
rights have been assigned pursuant to Section 9(f) of this Agreement.

               "Majority Investors" means at any time the holders of a majority
of the Conversion Stock.

               "Person" shall mean an individual, partnership, corporation,
association, trust, joint venture, unincorporated organization and any
government, governmental department or agency or political subdivision thereof.

               "Purchase Agreement" means the Securities Purchase Agreement of
even date herewith among the Company and each of the parties named therein as
"Investors."

               "Redeemable Preferred Stock" means the Company's Redeemable
Preferred Stock, par value $.0001 per share.

               "Registrable Securities" means the following (in each case as
adjusted for stock splits, recapitalizations and other similar events) (i) the
Conversion Stock; (ii) any Common Stock or other securities issued or issuable
with respect to the Conversion Stock pursuant to any stock split, stock
dividend, recapitalization, or similar event; (iii) securities (other than
Redeemable Preferred Stock) issued in replacement or exchange of any of the
securities issued in clauses (i) or (ii) above; and (iv) Founder Stock;
provided, however, that any and all shares described in clauses (i)-(iv) above
that are resold to the public pursuant to a registration statement or pursuant
to Rule 144(g) promulgated under the Securities Act shall cease to be
Registrable Securities upon such resale.

               "Registration Expenses" means all expenses incident to the
Company's performance of or compliance with this Agreement, including, without
limitation, all registration, filing, listing and National Association of
Securities Dealers, Inc. ("NASD") fees, all fees and expenses of complying with
securities or blue sky laws, all word processing, duplicating and printing
expenses,


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all messenger and delivery expenses, any transfer taxes, the fees and expenses
of the Company's legal counsel and independent public accountants, including the
expenses of any special audits or "cold comfort" letters required by or incident
to such performance and compliance, the reasonable fees and disbursements of one
counsel for all of the Investors, and any fees and disbursements of underwriters
customarily paid by issuers or sellers of securities; provided, however, that
Registration Expenses shall not include underwriting discounts and commissions.

               "Required Registration" has the meaning specified in Section 2(a)
of this Agreement.

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

               "Series A Preferred Stock" means the Company's Series A Preferred
Stock, par value $.0001 per share.

               "Series B Preferred Stock" means the Company's Series B Preferred
Stock, par value $.0001 per share.

               "Series C Preferred Stock" means the Company's Series C Preferred
Stock, par value $.0001 per share.

               "Series D Preferred Stock" means the Company's Series D Preferred
Stock, par value $.0001 per share.

               "Underwriter's Maximum Number" has the meaning specified in
Section 2(f) of this Agreement.

        2. Registration.

               (a) Requested Registration. At any time after the earlier of: (i)
Company's initial public offering of equity securities, or (ii) the second
anniversary of the date of this Agreement, upon written request by the Majority
Investors that the Company effect the registration under the Securities Act of
all or part of the Registrable Securities (a "Requested Registration"), the
Company shall use its diligent efforts to effect the registration under the
Securities Act of the Registrable Securities that the Company has been so
requested to register by such Majority Investors within ninety (90) days after
receipt of such request or within forty-five (45) days after receipt of such
request if the Company is qualified to file a registration statement on
Commission Form S-3 or any successor or similar short-form registration
statement (collectively, "Commission Form S-3"); provided, however, that (i) the
Company shall not be obligated to effect a Requested Registration on Commission
Form S-3 pursuant to this Section 2(a) unless the anticipated aggregate offering
price of the Registrable Securities to be sold pursuant thereto is at least
$5,000,000 in the aggregate and (ii) each Investor, acting alone, shall have the
right to request that the Company register all or any portion of such Investor's
Registrable Securities (subject to the $5,000,000 aggregate offering threshold
referenced above) if the Company is qualified to file a registration statement
on Commission Form S-3, whether or not the Majority Investors join in such
request, and thereupon the Company shall use its diligent efforts to effect such
registration in accordance with the provisions


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hereof. The Company must effect an unlimited number of registrations pursuant to
this Section 2(a) to the extent such registrations may be effected on Commission
Form S-3 (and meet the $5,000,000 aggregate offering threshold referenced
above); provided, however, that (i) the Company shall not be obligated to effect
more than three (3) Requested Registrations hereunder on Commission Form S-1 or
any other Commission Form other than Commission Form S-3; and (ii) the Company
shall not be obligated to keep effective at any one time more than three
registration statements on Commission Form S-3 with respect to Registrable
Securities requested to be registered in accordance with this Section 2(a), and
if the Company is requested to effect the registration of Registrable Securities
on Commission Form S-3 at a time when it is keeping three such registration
statements effective, it may delay effecting such Requested Registration until
it is no longer required in accordance with Section 3(a)(iii) to keep effective
one of the then effective registration statements on Commission Form S-3.
Subject to Section 2(f) and the next succeeding sentence of this section 2(a),
the Company may include in such Requested Registration other securities of the
Company for sale, for the Company's account or for the account of any other
person, if and to the extent that the managing underwriter determines that the
inclusion of such additional shares will not interfere with the orderly sale of
the Registrable Securities subject to such Requested Registration at a price
range approved in writing by the Majority Investors. Upon receipt of any such
written request by the Majority Investors that the Company effect a Requested
Registration, the Company will notify each other Investor of such request at
least thirty (30) days prior to the filing of such registration statement, and
upon the request of any such Investor given in writing within fifteen (15) days
after the receipt of such notice, subject to Section 2(f), the Company shall as
soon as practicable thereafter cause any of the Registrable Securities specified
by any such Investor to be included in such registration statement (and any
related qualification under blue sky laws or other compliance) to the extent
such registration is permissible under the Securities Act and subject to the
conditions of the Securities Act.).

               (b) Incidental Registration. If the Company for itself or any of
its security holders shall at any time or times after the date hereof determine
or is requested in accordance with Section 2(a) to register under the Securities
Act any shares of its capital stock or other securities (other than (i) the
registration of an offer, sale or other disposition of securities solely to
employees of, or other persons providing services to, the Company, or any
subsidiary pursuant to an employee or similar benefit plan registered on Form
S-8 or a similar successor form or (ii) relating to a merger, acquisition or
other transaction of the type described in Rule 145 under the Securities Act or
a comparable or successor rule, registered on Form S-4 or similar or successor
forms), on each such occasion the Company will notify each Investor of such
determination or request at least thirty (30) days prior to the filing of such
registration statement, and upon the request of any Investor given in writing
within twenty (20) days after the receipt of such notice, subject to Section
2(f), the Company shall use its diligent efforts as soon as practicable
thereafter to cause any of the Registrable Securities specified by any such
Investor to be included in such registration statement to the extent such
registration is permissible under the Securities Act and subject to the
conditions of the Securities Act (an "Incidental Registration").

               (c) Registration Statement Form. The Company shall, if permitted
by law, effect any applicable registration requested under Section 2 by the
filing of a registration statement on Commission Form S-3 and shall use its
diligent efforts to take any action necessary to maintain its eligibility to
utilize Commission Form S-3 to permit resales as requested by the Investors with


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respect to "Transactions Involving Secondary Offerings" as described in General
Instruction 1.B.3 of Commission Form S-3.

               (d) Expenses. The Company shall pay all Registration Expenses
incurred in connection with any Incidental Registration and any Requested
Registrations meeting the requirements set forth in this Section 2, including
the fees and disbursements of one firm of attorneys representing the Investors
participating in each Incidental Registration and each Requested Registration.

               (e) Effective Registration Statement. A Requested Registration or
an Incidental Registration requested pursuant to Section 2(a) or Section 2(b),
respectively, shall not be deemed to have been effected unless the registration
statement filed with respect thereto in accordance with the Securities Act has
become effective with the Commission. Notwithstanding the foregoing, a
registration statement will not be deemed to have become effective if (i) after
it has become effective with the Commission, such registration is made subject
to any stop order, injunction, or other order or requirement of the Commission
or other governmental agency or any court proceeding for any reason other than a
misrepresentation or omission by any Investor, or (ii) the conditions to closing
specified in the purchase agreement or underwriting agreement entered into in
connection with such registration are not satisfied, other than solely by reason
of some act or omission by any Investor.

               (f) Priority in Registration. If a Requested Registration or an
Incidental Registration is an underwritten offering, and the managing
underwriters shall give written advice to the Investors or the Company, as the
case may be, that, in their opinion, market conditions dictate that no more than
a specified maximum number of securities (the "Underwriter's Maximum Number")
could successfully be included in such registration, then the Company and the
Investors will be able to participate in such offering in the following order of
priority: (A) in the case of a Requested Registration, (i) first, there shall be
included in such registration that number of Registrable Securities issued upon
conversion of shares of Convertible Preferred Stock that the holders thereof
shall have requested to be included in such offering, either in a request by the
Majority Investors or in a notice given to the Company pursuant to the final
sentence of Section 2(a), pro rata in accordance with the relative number of
shares originally requested to be included in such registration statement by
such Investors, to the full extent of the Underwriter's Maximum Number; (ii)
second, the Company shall be entitled to include in such registration that
number of securities that it proposes to offer and sell for its own account to
the full extent of the remaining portion of the Underwriter's Maximum Number;
and (iii) third, to the extent not inconsistent with any registration rights
hereafter granted by the Company to holders of Company securities, the Founder
Investors shall be entitled to include in such registration that number of
shares of Registrable Securities that the Founder Investors shall have requested
to be included in such registration to the full extent of the remaining portion
of the Underwriter's Maximum Number; and (B) in the case of an Incidental
Registration (i) first, the Company shall be entitled to include in such
registration that number of securities that the Company proposes to offer and
sell for its own account in such registration and that does not exceed the
Underwriter's Maximum Number; (ii) second, the Company will be obligated and
required to include in such registration that number of shares of Registrable
Securities issued upon the conversion of shares of Convertible Preferred Stock
that the holders thereof shall have requested to be included in such offering,
pro rata in accordance with the relative number of shares originally requested
to be included in such registration statement by such Investors, to the full


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extent of the remaining portion of the Underwriter's Maximum Number; and (iii)
third, to the extent not inconsistent with any registration rights hereafter
granted by the Company to holders of the Company's securities, the Company will
be obligated and required to include in such registration that number of shares
of Founder Stock requested to be included in such offering by the Founder
Investors along with other securities of the Company that shall have been
requested by other Persons having registration rights pursuant to one or more
other registration rights agreements with the Company. If the number of shares
of Registrable Securities requested to be included in an underwritten offering
exceeds the then remaining portion of the Underwriter's Maximum Number as
provided in clauses (A) and (B) of this Section 2(f), as the case may be, then
the Investors whose aggregate request so exceeds the then remaining portion of
the Underwriter's Maximum Number may include shares of Registrable Securities in
such underwritten offering pro rata in accordance with the relative number of
shares originally requested to be included in such offering by such Investors in
the writing delivered in accordance with Section 2(a) or Section 2(b), as the
case may be.

               (g) Delay of Registration. Notwithstanding anything in this
Section 2 to the contrary, the Company shall have the right to delay any
registration of Registrable Securities requested pursuant to paragraph (a) of
this Section 2 for up to ninety (90) days if such registration would, in the
judgment of the Company's Board of Directors, be detrimental to the Company and
its stockholders for such registration statement to be filed on or before the
date filing would otherwise be required and it would be essential to defer such
filing.

               (h) Limitations. Notwithstanding anything in this Agreement to
the contrary, the Company shall not be obligated to take any action to effect
registration, qualification or compliance with respect to its Registrable
Securities:

                      (i) in any particular jurisdiction in which the Company
would be required to execute a general consent to service of process unless the
Company is already subject to service in such jurisdiction and except as
required by the Securities Act;

                      (ii) that would require it to qualify generally to do
business in any jurisdiction in which it is not already so qualified;

                      (iii) that would subject it to general taxation in a
jurisdiction in which it is not already subject generally to taxation; or

                      (iv) during the period starting with the date sixty (60)
days prior to the Company's estimated date of filing of, and ending on the 180th
day immediately following the effective date of any registration statement
pertaining to securities of the Company, provided that the Company is actively
employing in good faith reasonable efforts to cause such registration statement
to become effective.

               (i) Termination. The rights to Requested Registrations in
accordance with Section 2(a) and to participate in Incidental Registrations in
accordance with Section 2(b) shall terminate on the seventh anniversary of the
Company's first Qualified Public Offering (as such term


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is defined in the Company's Third Amended and Restated Certificate of
Incorporation as in effect on the date hereof).

        3. Registration Procedures.

               (a) If and whenever the Company is required to use its diligent
efforts to effect the registration of any Registrable Securities under the
Securities Act as provided in Section 2, the Company, as expeditiously as
possible and subject to the terms and conditions of Section 2, will do the
following:

                      (i) prepare and file with the Commission the requisite
registration statement to effect such registration and use its diligent efforts
to cause such registration to become and remain effective for the period set
forth in Section 3(a)(iii) below;

                      (ii) permit any Investor who, in the reasonable judgment
of the Company's counsel, might be deemed to be an underwriter or a controlling
person of the Company, to participate in the preparation of such registration
statement;

                      (iii) prepare and file with the Commission such amendments
and supplements to such registration statement and the prospectus used in
connection therewith as may be necessary to keep such registration statement
effective and to comply with the provisions of the Securities Act with respect
to the disposition of all securities covered by such registration statement
until the earlier of such time as all of such securities have been disposed of
in accordance with the intended methods of disposition by the seller or sellers
thereof set forth in such registration statement or the expiration of 180 days
after such registration statement becomes effective (such period of 180 days to
be extended one day for each day during such period that such registration
statement shall be subject to any stop order suspending the effectiveness of the
registration statement, or of any order suspending or preventing the use of any
related prospectus or suspending the qualification of any Registrable Securities
included in such registration statement for sale in any jurisdiction);

                      (iv) furnish to the Investors such number of conformed
copies of such registration statement and of each such amendment and supplement
thereto (in each case including all exhibits), such number of copies of the
prospectus contained in such registration statement (including each preliminary
prospectus and any summary prospectus) and any other prospectus filed under Rule
424 under the Securities Act, in conformity with the requirements of the
Securities Act, and such other documents, as the purchaser or any Investor of
Registrable Securities to be sold under such registration statement may
reasonably request;

                      (v) use its diligent efforts to register or qualify all
Registrable Securities covered by such registration statement under such other
United States state securities or blue sky laws of such jurisdictions as any
Investor of Registrable Securities to be sold under such registration statement
shall reasonably request, to keep such registration or qualification in effect
for the time period set forth in Section 3(a)(iii) hereof, and take any other
action that may be reasonably necessary or advisable to enable the Investor who
holds Registrable Securities to be sold under such registration statement to
consummate the disposition thereof in such jurisdictions;


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                      (vi) use its diligent efforts to cause all Registrable
Securities covered by such registration statement to be registered with or
approved by such other United States state governmental agencies or authorities
as may be necessary to enable the Investor of Registrable Securities to be sold
under such registration statement to consummate the intended disposition of such
Registrable Securities;

                      (vii) in the event of the issuance of any stop order
suspending the effectiveness of the registration statement, or of any order
suspending or preventing the use of any related prospectus or suspending the
qualification of any Registrable Securities included in such registration
statement for sale in any jurisdiction, the Company shall use its diligent
efforts promptly to obtain the withdrawal of such order;

                      (viii) use its diligent efforts to furnish to the
Investors of Registrable Securities to be sold under such registration statement
(1) an opinion, dated the effective date of the registration statement, of the
independent counsel representing the Company for the purposes of such
registration, addressed to the underwriters, if any, and to the Investors making
such request, stating that such registration statement has become effective
under the Securities Act and that (i) to the knowledge of such counsel, no stop
order suspending the effectiveness thereof has been issued and no proceedings
for that purpose have been instituted or are pending or contemplated under the
Securities Act; (ii) the registration statement, the related prospectus, and
each amendment or supplement thereto, comply as to form in all material respects
with the requirements of the Securities Act and the applicable rules and
regulations of the Commission thereunder (except that such counsel need express
no opinion as to financial statements and related schedules contained therein);
(iii) to the knowledge of such counsel, as of the effective date, neither the
registration statement, the prospectus, nor any amendment or supplement thereto
(other than the financial statements and related schedules therein), contains
any untrue statement of a material fact or omits a material fact necessary to
make the statements therein, in light of the circumstances under which they were
made, not misleading; (iv) the descriptions in the registration statement or the
prospectus, or any amendment or supplement thereto, of the securities to be
registered, insofar as such description purports to constitute a summary of the
terms of the securities to be registered, and the description of the
underwriting, insofar as such description purports to describe the provisions of
the laws and documents, which have been provided to counsel, directly pertaining
to the underwriting are accurate and fairly present the information required to
be shown; and (v) such counsel does not know of any pending legal or
governmental proceedings to which the Company is a party or of which any
property of the Company is the subject which, if determined adversely to the
Company, would individually or in the aggregate have a material adverse effect
on the then-current or future consolidated financial position, stockholders'
equity or results of operation of the Company, nor of any contracts or documents
or instruments of a character required to be described in the registration
statement or prospectus, or any amendment or supplement thereto or to be filed
as exhibits to the registration statement that are not described and filed as
required (such opinion of counsel shall additionally cover such legal matters
with respect to the registration in respect of which such opinion is being given
as the Investors may reasonably request and may contain such qualifications and
limitations as are customarily included in opinions of such sort); and (2) a
letter, dated the effective date of the registration statement, from the
independent certified public accountants of the Company, addressed to the
underwriters, if any, and to the Investors making such request, stating that
they are independent certified public accountants within the meaning of the
Securities Act and that in the


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opinion of such accountants, the financial statements and other financial data
of the Company included in the registration statement or the prospectus, or any
amendment or supplement thereto, comply as to form in all material respects with
the applicable accounting requirements of the Securities Act (such letter from
the independent certified public accountants shall additionally cover such other
financial matters (including information as to the period ending not more than
five business days prior to the date of such letter) with respect to the
registration in respect of which such letter is being given as the Investors may
reasonably request);

                      (ix) immediately notify the Investors of Registrable
Securities included in such registration statement at any time when a prospectus
relating thereto is required to be delivered under the Securities Act, of its
becoming aware of any event as result of which the prospectus included in such
registration statement, as then in effect, includes an untrue statement of
material fact or omits to state any material fact required to be stated therein
or necessary to make the statements therein not misleading in the light of the
circumstances under which they were made, and at the request of the Investors
promptly prepare and furnish to the Investors a reasonable number of copies of a
supplement to or an amendment of such prospectus as may be necessary so that, as
thereafter delivered to the purchasers of such securities, such prospectus shall
not include an untrue statement of a material fact or omit to state a material
fact required to be stated therein or necessary to make the statements therein
not misleading in the light of the circumstances under which they were made;

                      (x) otherwise use its diligent efforts to comply with all
applicable rules and regulations of the Commission, and make available to its
security holders, as soon as reasonably practicable, an earnings statement
covering the period of at least twelve months, but not more than eighteen
months, beginning with the first full calendar month after the effective date of
such registration statement, which earnings statement shall satisfy the
provisions of Section 11(a) of the Securities Act and Rule 158 thereunder;

                      (xi) provide a transfer agent for all Registrable
Securities covered by such registration statement not later than the effective
date of such registration statement; and

                      (xii) use its diligent efforts to list all Registrable
Securities covered by such registration statement on any securities exchange on
which any of the Registrable Securities are then listed.

               (b) The Company may require each Investor of Registrable
Securities to be sold under such registration statement to furnish the Company
with such information and undertakings as it may reasonably request regarding
such Investor and the distribution of such securities as the Company may from
time to time reasonably request in writing.

               (c) Each Investor, by execution of this Agreement, agrees (A)
that upon receipt of any notice from the Company, or upon such Investor's
otherwise becoming aware, of the happening of any event of the kind described in
subdivision (a)(ix) of this Section 3, such Investor will forthwith discontinue
its disposition of Registrable Securities pursuant to the registration statement
relating to such Registrable Securities until the receipt by such Investor of
the copies of the supplemented or amended prospectus contemplated by subdivision
(a)(ix) of this Section 3 and, if so


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directed by the Company, will deliver to the Company all copies other than
permanent file copies, then in possession of the Investors of the prospectus
relating to such Registrable Securities current at the time of receipt of such
notice and (B) that it will immediately notify the Company, at any time when a
prospectus relating to the registration of such Registrable Securities is
required to be delivered under the Securities Act, of the happening of any event
as a result of which information previously furnished in writing by such
Investor to the Company specifically for inclusion in such prospectus contains
an untrue statement of a material fact or omits to state any material fact
required to be stated therein or necessary to make the statements therein not
misleading in the light of the circumstances under which they were made. In the
event the Company or any such Investor shall give any such notice, the period
referred to in subdivision (a)(iii) of this Section 3 shall be extended by a
number of days equal to the number of days during the period from and including
the giving of notice pursuant to subdivision (a)(ix) of this Section 3 to and
including the date when such Investor shall have received the copies of the
supplemented or amended prospectus contemplated by subdivision (a)(ix) of this
Section 3.

        4. Underwritten Offerings.

               (a) Underwritten Offering. In connection with any underwritten
offering pursuant to a registration requested under Section 2(a), the Company
will enter into an underwriting agreement with the underwriters for such
offering, such agreement to be in form and substance reasonably satisfactory to
the Majority Investors and such underwriters in their reasonable judgment and to
contain such representations and warranties by the Company and such other terms
as are customarily contained in agreements of that type, including, without
limitation, indemnities to the effect and to the extent provided in Section 6.
Each Investor participating in such underwritten registration shall be a party
to such underwriting agreement and may, at such Investor's option, require that
any or all of the representations and warranties by, and the other agreements on
the part of, the Company to and for the benefit of such underwriters shall also
be made to and for the benefit of each such Investor and that any or all of the
conditions precedent to the obligations of such underwriters under such
underwriting agreement be conditions precedent to the obligations of such
Investor. No Investor participating in any such underwritten registration shall
be required by the provisions hereof to make any representations or warranties
to or agreements with the Company or the underwriters other than
representations, warranties or agreements regarding such Investor and its
intended method of distribution and any other representation required by law.

               (b) Selection of Underwriters. If a Requested Registration
pursuant to Section 2(a) involves an underwritten offering, then the Company
shall select the underwriter from underwriting firms of national reputation,
subject to the reasonable approval of the Investors of a majority of the
Registrable Securities to be included in such registration.

               (c) Holdback Agreements. Each Investor hereby agrees, if so
requested by the managing underwriter in each underwritten registration of the
Company's capital stock or other securities described in Section 2(a) and
Section 2(b) in a writing referencing this Section 4(c), not to effect (except
as part of such underwritten registration in accordance with the provisions
hereof) any sale, distribution, short sale, loan, grant of options for the
purchase of, or otherwise dispose of, any Registrable Securities for such period
as such underwriter requests, such period in no event to commence earlier than
seven (7) days prior to, or to end more than 180 days after, the effective date


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of such registration. Each Investor further agrees that the Company may instruct
its transfer agent to place stop transfer notations in its records to enforce
the provisions of this Section 4(c).

        5. Preparation, Reasonable Investigation. In connection with the
preparation and filing of each registration statement under the Securities Act,
the Company will give the Investors of Registrable Securities to be sold under
such registration statement, the underwriters, if any, and their respective
counsel and accountants, advance draft copies of such registration statement,
each prospectus included therein or filed with the Commission at least 5
business days prior to the filing thereof with the Commission, and any
amendments and supplements thereto promptly as they become available, and will
give each of them such access to its books and records and such opportunities to
discuss the business of the Company with its officers and the independent public
accountants who have certified its financial statements as shall be necessary,
in the opinion of such Investors and such underwriters' respective counsel, to
conduct a reasonable investigation within the meaning of the Securities Act.

        6. Indemnification and Contribution.

               (a) Indemnification by the Company. In the event of any
registration under the Securities Act pursuant to Section 2 of any Registrable
Securities covered by such registration, the Company will, and hereby does,
indemnify and hold harmless each Investor of Registrable Securities to be sold
under such registration statement, each such Investor's legal counsel, each
other person who participates as an underwriter in the offering or sale of such
securities (if so required by such underwriter as a condition to including the
Registrable Securities of the Investors in such registration) and each other
person, if any, who controls any such Investor or any such underwriter within
the meaning of the Securities Act (collectively, the "Indemnified Parties"),
against any losses, claims, damages or liabilities, joint or several, to which
the Investors or underwriter or controlling person may become subject under the
Securities Act or otherwise, insofar as such losses, claims, damages or
liabilities (or actions or proceedings, whether commenced or threatened, in
respect thereof) arise out of or are based upon any untrue statement or alleged
untrue statement of any material fact contained in any registration statement
under which such securities were registered under the Securities Act, any
preliminary prospectus, final prospectus or summary prospectus contained therein
or any document incorporated therein by reference, or any amendment or
supplement thereto, or any omission or alleged omission to state therein a
material fact required to be stated therein or necessary to make the statements
therein in light of the circumstances in which they were made not misleading, or
arise out of any violation by the Company of any rule or regulation promulgated
under the Securities Act or state securities law applicable to the Company and
relating to action or inaction required of the Company in connection with any
such registration, and the Company will reimburse the Indemnified Parties for
any legal or any other expenses reasonably incurred by them in connection with
investigating or defending any such loss, claim, liability, action or
proceeding; provided, however, that the Company shall not be liable to any
Indemnified Party in any such case to the extent that any such loss, claim,
damage, liability (or action or proceeding in respect thereof) or expense arises
out of or is based upon any untrue statement or alleged untrue statement or
omission or alleged omission made in such registration statement, any such
preliminary prospectus, final prospectus, summary prospectus, amendment or
supplement in reliance upon and in conformity with information regarding the
Indemnified Party and furnished to the Company in writing by any Indemnified
Party specifically for use therein.


                                      -11-
<PAGE>   12

               (b) Indemnification by the Investors. As a condition to including
any Registrable Securities of any holder thereof in any registration statement
filed pursuant to Section 2, such holder of Registrable Securities hereby agrees
to indemnify and hold harmless (in the same manner and to the same extent as set
forth in subdivision (a) of this Section 6) the Company, each director of the
Company, each officer of the Company and each other person, if any, who controls
the Company within the meaning of the Securities Act, with respect to any
statement or alleged statement in or omission or alleged omission from such
registration statement, any preliminary prospectus, final prospectus or summary
prospectus contained therein, or any amendment or supplement thereto, if, and
only if, such statement or alleged statement or omission or alleged omission was
made in reliance upon and in conformity with information regarding the
Indemnified Party and furnished in writing to the Company directly by such
person or entity specifically for use therein; provided, however, that the
obligation of any Investor hereunder shall be limited to an amount equal to the
net proceeds received by such Investor upon the sale of Registrable Securities
sold in the offering covered by such registration, unless such liability arises
out of or is based upon such Investor's willful misconduct.

               (c) Notices of Claims, etc. Promptly after receipt by an
Indemnified Party of notice of the commencement of any action or proceeding
involving a claim referred to in the preceding subdivisions of this Section 6,
such Indemnified Party will, if a claim in respect thereof is to be made against
a party required to provide indemnification (an "Indemnifying Party"), give
written notice to the latter of the commencement of such action, provided,
however, that the failure of any Indemnified Party to give notice as provided
herein shall not relieve the Indemnifying Party of its obligation under the
preceding subdivisions of this Section 6, except to the extent that the
Indemnifying Party is actually prejudiced by such failure to give notice. In
case any such action is brought against an Indemnified Party, unless in such
Indemnified Party's reasonable judgment a conflict of interest between such
Indemnified and indemnifying parties may exist in respect of such claim, the
Indemnifying Party shall be entitled to participate in and to assume the defense
thereof, jointly with any other Indemnifying Party similarly notified to the
extent that it may wish, with counsel reasonably satisfactory to such
Indemnified Party, and after notice from the Indemnifying Party to such
Indemnified Party of its election so to assume the defense thereof, the
Indemnifying Party shall not be liable to such Indemnified Party for any legal
or other expenses subsequently incurred by the latter in connection with the
defense thereof other than reasonable costs of investigation. No Indemnifying
Party shall consent to entry of any judgment or enter into any settlement
without the consent of the Indemnified Party 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.

               (d) Other Indemnification. Indemnification similar to that
specified in the preceding subdivisions of this Section 6 (with appropriate
modifications) shall be given by the Company and each holder of Registrable
Securities, respectively, included in any registration statement to each other
and any underwriter, as applicable, with respect to any required registration or
other qualification of securities under any Federal or state law or regulation
of any governmental authority, other than the Securities Act; provided, however,
that no Investor shall be obligated to indemnify any party to an extent or
regarding any matter not addressed in Section 6(b) hereof unless requested by
the underwriter in a public offering of the Company's Securities.


                                      -12-
<PAGE>   13

               (e) Indemnification Payment. The indemnification required by this
Section 6 shall be made by periodic payments of the amount thereof during the
course of the investigation or defense, as and when bills are received or
expense, loss, damage or liability is incurred.

               (f) Survival of Obligations. The obligations of the Company and
of the Investors under this Section 6 shall survive the completion of any
offering of Registrable Securities under this Agreement.

               (g) Contribution. If the indemnification provided for in this
Section 6 is unavailable or insufficient to hold harmless an Indemnified Party,
then each Indemnifying Party shall contribute to the amount paid or payable to
such Indemnified Party as a result of the losses, claims, damages or liabilities
referred to in this Section 6 an amount or additional amount, as the case may
be, in such proportion as is appropriate to reflect the relative fault of the
Indemnifying Party or parties, on the one hand, and the Indemnified Party, on
the other, in connection with the statements or omissions which resulted in such
losses, claims, demands or liabilities as well as any other relevant equitable
considerations; provided however, that the obligation of any Investor for
contribution pursuant to this Section shall be limited to an amount equal to the
net proceeds received by such Investor upon the sale of Registrable Securities
sold in the offering covered by such registration less any amount previously
contributed pursuant to this Section. The relative fault shall be determined by
reference to, among other things, whether the untrue or alleged untrue statement
of a material fact or the omission or alleged omission to state a material fact
relates to information supplied by the Indemnifying Party or parties, on the one
hand, or the Indemnified Party, on the other, and the parties' relative, intent,
knowledge, access to information and opportunity to correct or prevent such
untrue statement or omission. The amount paid to an Indemnified Party as a
result of the losses, claims, damages or liabilities referred to in the first
sentence of this Section 6(g) shall be deemed to include any legal or other
expenses reasonably incurred by such Indemnified Party in connection with
investigating or defending any action or claim which is the subject of this
Section 6. No person guilty of fraudulent misrepresentation within the meaning
of Section 11(f) of the Securities Act) shall be entitled to contribution from
any Person who was not guilty of such fraudulent misrepresentation.

        7. Covenants Relating to Rule 144. With a view to making available the
benefits of certain rules and regulations of the Commission which may at any
time permit the sale of securities of the Company to the public without
registration after such time as a public market exists for the Common Stock of
the Company, the Company agrees to do the following:

               (a) to make and keep public information available in accordance
with Rule 144 under the Securities Act at all times after the effective date of
the first registration under the Securities Act filed by the Company for an
offering of its securities to the general public;

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

               (c) so long as an Investor owns any Registrable Securities, to
furnish to the Investor forthwith upon request a written statement by the
Company as to its compliance with the


                                      -13-
<PAGE>   14

reporting requirements of said Rule 144 (at any time after 90 days after 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 Securities Act and
the Exchange Act (at any time after it has become subject to such reporting
requirements) and a copy of the most recent annual or quarterly report of the
Company, and such other reports and documents of 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.

        8. Other Registration Rights. The Company represents and warrants that
it has not granted any registration rights to any Person other than established
by this Agreement. Except with the consent of the Majority Investors, the
Company shall not grant to any Person any registration rights more favorable
than or inconsistent with any of those contained herein, so long as any of the
registration rights under this Agreement remain in effect.

        9. Miscellaneous.

               (a) Specific Performance. The parties hereto acknowledge that
there may be no adequate remedy at law if any party fails to perform any of its
obligations hereunder and that each party may be irreparably harmed by any such
failure, and accordingly agree that each party, in addition to any other remedy
to which it may be entitled at law or in equity, shall be entitled to compel
specific performance of the obligations of any other party under this Agreement
in accordance with the terms and conditions of this Agreement.

               (b) Notices. All demands, notices, requests, consents and other
communications required or permitted under this Agreement shall be in writing
and shall be personally delivered or sent by facsimile machine (with a
confirmation copy sent by one of the other methods authorized in this Section),
commercial (including FedEx) or U.S. Postal Service overnight delivery service,
or, deposited with the U.S. Postal Service mailed first class, registered or
certified mail, postage prepaid, as set forth below:

               If to the Company or any Founder Investor, addressed to:

                      Mr. Clifford G. Rudolph
                      Chairman and Chief Executive Officer
                      100 Stony Point Road, Suite 130
                      Santa Rosa, California 95401
                      Facsimile:  (707) 535-8909

               with a copy to:

                      Wilson Sonsini Goodrich & Rosati, P.C.
                      650 Page Mill Road
                      Palo Alto, California 94304-1050
                      Attn: Daniel R. Mitz, Esq.
                      Telecopy:  (650) 493-6811


                                      -14-
<PAGE>   15

               If to any Investor, at its address set forth on Schedule 1
hereto:

               with a copy, if to a holder of Series A Preferred Stock,
               Redeemable Preferred Stock, Series B Preferred Stock, to:

                      Edwards & Angell, LLP
                      101 Federal Street
                      Boston, Massachusetts 02110
                      Attn:  Leonard Q. Slap, Esq.
                      Facsimile: (617) 439-4170

        Notices shall be deemed given upon the earlier to occur of (i) receipt
by the party to whom such notice is directed; (ii) if sent by facsimile machine,
on the day (other than a Saturday, Sunday or legal holiday in the jurisdiction
to which such notice is directed) such notice is sent if sent (as evidenced by
the facsimile confirmed receipt) prior to 5:00 p.m. Eastern Time and, if sent
after 5:00 p.m. Eastern Time, on the day (other than a Saturday, Sunday or legal
holiday in the jurisdiction to which such notice is directed) after which such
notice is sent; (iii) on the first business day (other than a Saturday, Sunday
or legal holiday in the jurisdiction to which such notice is directed) following
the day the same is deposited with the commercial carrier if sent by commercial
overnight delivery service; or (iv) the fifth day (other than a Saturday, Sunday
or legal holiday in the jurisdiction to which such notice is directed) following
deposit thereof with the U.S. Postal Service as aforesaid. Each party, by notice
duly given in accordance therewith may specify a different address for the
giving of any notice hereunder.

               (c) Governing Law. This Agreement shall be construed in
accordance with and governed by the laws of the State of Delaware (without
giving effect to any conflicts or choice of laws provisions that would cause the
applications of the domestic substantive laws of any other jurisdiction).

               (d) Headings. The descriptive headings of the several sections
and paragraphs of this Agreement are inserted for convenience only, and do not
constitute a part of this Agreement and shall not affect in any way the meaning
or interpretation of this Agreement.

               (e) Entire Agreement; Amendments. This Agreement and the other
writings referred to herein or delivered pursuant hereto which form a part
hereof contain the entire understanding of the parties with respect to its
subject matter. This Agreement supersedes all prior agreements (including the
Prior Agreement) and understandings between the parties with respect to its
subject matter. This Agreement may be amended and the observance of any term of
this Agreement may be waived (either generally or in a particular instance and
either retroactively or prospectively) only by a written instrument duly
executed by the Company and the Majority Investors. Each holder of any
Registrable Securities at the time or thereafter outstanding shall be bound by
an amendment or waiver authorized by this Section 9(e), whether or not any such
Registrable Securities shall have been marked to indicate such consent.

               (f) Assignability. This Agreement and all of the provisions
hereof will be assigned, without the consent of the Company, by any Investor to,
and shall inure to the benefit of,


                                      -15-
<PAGE>   16

any permitted purchaser, transferee or assignee of more than 250,000 shares of
Registrable Securities (as adjusted for stock splits, recapitalizations, and
other similar events) unless the Investor specifies otherwise in connection with
particular transfers of Registrable Securities, and any such permitted
purchaser, transferee or assignee shall take shares of Registrable Securities
subject to, and shall be bound by, the terms of this Agreement; provided in each
instance that the transferee or assignee of such rights assumes in writing the
obligations of such Investor under this Agreement. However, the Company shall
not be required to recognize any such purchaser, transferee or assignee as a
Investor under this Agreement unless and until either (i) such person becomes
the holder of record of Registrable Securities, (ii) the Company receives
written notice of such purchase, transfer or assignment, or (iii) such purchase,
transfer or assignment is to an entity which is wholly-owned by such Investor or
is under common control (as determined in accordance with the Securities
Exchange Act of 1934, as amended) with such Investor and the Company has
provided written consent which shall not be unreasonably: (i) withheld, (ii)
conditioned or (iii) delayed.

               (g) Counterparts. This Agreement may be executed in any number of
counterparts, and by the different parties hereto as separate counterparts, each
of which shall be an original, and all of which together shall constitute one
and the same instrument.


                                      -16-
<PAGE>   17

        IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first written above.

                                    COMPANY:


                                    ATG GROUP, INC.


                                    By: /s/ THOMAS A. GRINA
                                       -----------------------------------------
                                       Thomas A. Grina, Senior Vice President


                                    INVESTORS:

                                    ALTA COMMUNICATIONS VII, L.P.

                                    BY: ALTA COMMUNICATIONS VII MANAGERS, LLC,
                                         ITS GENERAL PARTNER


                                    By: /s/ EILEEN McCARTHY
                                       -----------------------------------------
                                       Name: Eileen McCarthy
                                            ------------------------------------
                                       Title: Member
                                             -----------------------------------

                                    ALTA VII ASSOCIATES LLC

                                    BY: ALTA COMMUNICATIONS, INC., ITS MANAGER


                                    By: /s/ EILEEN McCARTHY
                                       -----------------------------------------
                                       Name: Eileen McCarthy
                                            ------------------------------------
                                       Title: VP - Finance
                                             -----------------------------------


                                    NORWEST VENTURE PARTNERS VI,
                                       LP

                                    BY: ITASCA VC PARTNERS VI, LLP, ITS GENERAL
                                          PARTNER

                                    By: /s/ JOHN P. WHALEY
                                       -----------------------------------------
                                       John P. Whaley, Partner


  [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]

<PAGE>   18

                                    NORWEST EQUITY PARTNERS VI,
                                      LP

                                    BY: ITASCA LBO PARTNERS VI, LLP, ITS GENERAL
                                          PARTNER


                                    By: /s/  JOHN P. WHALEY
                                       -----------------------------------------
                                       John P. Whaley, Partner


                                    ONELIBERTY FUND IV, L.P.

                                    BY: ONELIBERTY PARTNERS IV, LLC, ITS GENERAL
                                          PARTNER


                                    By: /s/ EDWIN M. KANIA, JR.
                                       -----------------------------------------
                                       Edwin M. Kania, Jr., Managing Member


                                    ONELIBERTY ADVISORS FUND IV,
                                      L.P.

                                    BY: ONELIBERTY PARTNERS IV, L.L.C., ITS
                                          GENERAL PARTNER


                                    By: /s/ EDWIN M. KANIA, JR.
                                       -----------------------------------------
                                       Edwin M. Kania, Jr.,
                                       Managing Member


  [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]

<PAGE>   19

                                    CENTENNIAL FUND V, L.P.

                                    BY: CENTENNIAL HOLDINGS V, L.P.,
                                        ITS GENERAL PARTNER

                                    By: /s/ ADAM GOLDMAN
                                       -----------------------------------------
                                       Adam Goldman, General Partner



                                    CENTENNIAL FUND VI, L.P.

                                    BY: CENTENNIAL HOLDINGS VI, LLC,
                                        ITS GENERAL PARTNER

                                    By: /s/ ADAM GOLDMAN
                                       -----------------------------------------
                                       Adam Goldman, Managing Principal



                                    CENTENNIAL ENTREPRENEURS FUND VI, L.P.

                                    BY: CENTENNIAL HOLDINGS VI, LLC,
                                        ITS GENERAL PARTNER

                                    By: /s/ ADAM GOLDMAN
                                       -----------------------------------------
                                       Adam Goldman, Managing Principal



                                    CENTENNIAL HOLDINGS I, LLC

                                    By: /s/ ADAM GOLDMAN
                                       -----------------------------------------
                                       Adam Goldman, Senior Vice President


  [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]

<PAGE>   20

                                    BCI GROWTH V, L.P.

                                    BY: GLENPOINTE ASSOCIATES V, LLC

                                    By: General Partner

                                       Name:  /s/ STEPHEN J. ELEY
                                            ------------------------------------
                                       Title:  Managing Member
                                             -----------------------------------
                                               Stephen J. Eley

                                    BCI INVESTORS, LLC

                                    By:   /s/ STEPHEN J. ELEY
                                        ----------------------------------------
                                       Name:  Stephen J. Eley
                                            ------------------------------------
                                       Title:  Managing Member
                                             -----------------------------------


                                    DUFF, ACKERMAN & GOODRICH L.P.

                                    BY: DAG LLC

                                    By: /s/ JOHN M. DUFF, JR.
                                       -----------------------------------------
                                       Name: John M. Duff, Jr.
                                            ------------------------------------
                                       Title: Managing Director
                                             -----------------------------------


                                    UNIONBANCAL VENTURE
                                    CORPORATION

                                    By: /s/ KEVIN SAMPSON  /s/ TERRI LANG
                                       -----------------------------------------
                                       Name: Kevin Sampson,  Terri Lang
                                            ------------------------------------
                                       Title: VP           VP
                                             -----------------------------------

                                     /s/ BILL O'MEARA
                                    --------------------------------------------
                                    Bill O'Meara


  [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]

<PAGE>   21



                                    FIRST UNION CAPITAL PARTNERS


                                    By: /s/ SCOTT PERPER
                                       -----------------------------------------
                                       Scott Perper, Managing Partner


                                    JP MORGAN INVESTMENT
                                      CORPORATION


                                    By: /s/ JOHN WATKINS
                                       -----------------------------------------
                                       John Watkins, Managing Director


                                    SIXTY WALL STREET SBIC FUND,
                                      L.P.


                                    By: /s/ JOHN WATKINS
                                       -----------------------------------------
                                       John Watkins, Vice President


                                    AT&T VENTURE FUND II, LP

                                    BY: VENTURE MANAGEMENT, LLC, ITS GENERAL
                                          PARTNER


                                    By: /s/ NEAL M. DOUGLAS
                                       -----------------------------------------
                                       Neal M. Douglas, Manager


  [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]

<PAGE>   22

                                    SPECIAL PARTNERS FUND, LP

                                    BY: VENTURE MANAGEMENT III, LLC, ITS GENERAL
                                          PARTNER


                                    By: /s/ NEAL M. DOUGLAS
                                       -----------------------------------------
                                       Neal M. Douglas, Manager


                                    SPECIAL PARTNERS FUND
                                      INTERNATIONAL, LP

                                    BY: VENTURE MANAGEMENT III, LLC, ITS
                                          INVESTMENT GENERAL PARTNER


                                    By: /s/ NEAL M. DOUGLAS
                                       -----------------------------------------
                                       Neal M. Douglas, Manager

                                    WS INVESTMENT COMPANY 99B


                                    By: /s/ DANIEL MITZ
                                       -----------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------


                                    WS INVESTMENT COMPANY 98B


                                    By: /s/ DANIEL MITZ
                                       -----------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------


 [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]

<PAGE>   23

                                    TPG PARTNERS II, L.P.
                                    BY: TPG GENPAR II, L.P.
                                    BY: TPG ADVISORS II, INC.


                                    By: /s/ JEFFREY A. SHAW
                                       -----------------------------------------
                                    Title:
                                          --------------------------------------

                                    TPG PARALLEL II, L.P.
                                    BY: TPG GENPAR II, L.P.
                                    BY: TPG ADVISORS II, INC.


                                    By: /s/ JEFFREY A. SHAW
                                       -----------------------------------------
                                    Title:
                                          --------------------------------------


                                    TPG INVESTORS II, L.P.
                                    BY: TPG GENPAR II, L.P.
                                    BY: TPG ADVISORS II, INC.


                                    By: /s/ JEFFREY A. SHAW
                                       -----------------------------------------
                                    Title:
                                          --------------------------------------


                                    TPG 1999 EQUITY PARTNERS II, L.P.
                                    BY: TPG ADVISORS II, INC.


                                    By: /s/ JEFFREY A. SHAW
                                       -----------------------------------------
                                    Title:
                                          --------------------------------------


 [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]


<PAGE>   24

                                    CORNERSTONE PROPERTIES I, LLC


                                    By: /s/ JOHN JACQUES
                                       -----------------------------------------
                                       John Jacques, Member


                                    GENERAL ELECTRIC CAPITAL CORPORATION

                                    By: /s/ MICHAEL J. BANN
                                       -----------------------------------------
                                       Name:  Michael J. Bann
                                            ------------------------------------
                                       Title: Senior Vice President
                                             -----------------------------------


                                    NEWCOURT COMMERCIAL FINANCE CORPORATION

                                    By:  /s/ JOHN P. SIRICO, II
                                       -----------------------------------------
                                       Name:  John P. Sirico, II
                                            ------------------------------------
                                       Title: Vice President
                                             -----------------------------------


                                     /s/ STEVEN W. ROTH
                                    --------------------------------------------
                                    Steven W. Roth


                                     /s/ LEONARD Q. SLAP
                                    --------------------------------------------
                                    Leonard Q. Slap


                                     /s/ MICHAEL E. GIBSON
                                    --------------------------------------------
                                    Michael E. Gibson


                                     /s/ KEVIN E. SOMERVILLE
                                    --------------------------------------------
                                    Kevin E. Somerville


 [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]


<PAGE>   25

                                    TELECOM PARTNERS II, L.P.

                                    BY: TELECOM MANAGEMENT II, L.L.C., ITS
                                          GENERAL PARTNER


                                    By: /s/ STEPHEN W. SCHOVEE
                                       -----------------------------------------
                                       Stephen W. Schovee, Managing Member

                                     /s/ G. JACKSON TANKERSLEY
                                    --------------------------------------------
                                    G. Jackson Tankersley, Jr., d/b/a The
                                          Millennial Fund


                                    THE RUDOLPH FAMILY 1997 TRUST
                                      DATED 10/10/97


                                    By: /s/ CLIFFORD G. RUDOLPH
                                       -----------------------------------------
                                       Clifford G. Rudolph, Trustee


                                     /s/ MICHAEL BLACK
                                    --------------------------------------------
                                    Michael Black


                                     /s/ CURTIS WHEELING
                                    --------------------------------------------
                                    Curtis Wheeling


                                     /s/ CLIFFORD G. RUDOLPH
                                    --------------------------------------------
                                    Clifford G. Rudolph


                                    EAGLE CREEK CAPITAL LLC


                                    By: /s/ DAVID E. BOYLE
                                       -----------------------------------------
                                       David E. Boyle, Vice President


 [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]


<PAGE>   26


                                     /s/ MARTIN KORMAN
                                    --------------------------------------------
                                    Martin Korman


                                     /s/ JOHN AGUIRRE
                                    --------------------------------------------
                                    John Aguirre


                                     /s/ DANIEL MITZ
                                    --------------------------------------------
                                    Daniel Mitz


                                     /s/ KURT HAMMERSTROM
                                    --------------------------------------------
                                    Kurt Hammerstrom


                                    ANDREW J. HIRSCH & NINA M. BROOKS, TRUSTEES
                                    OF HIRSCH/BROOKS FAMILY TRUST -
                                    1999 U/I DTD. 10/08/99


                                    By: /s/ ANDREW J. HIRSCH
                                       -----------------------------------------
                                       Andrew J. Hirsch, Trustee


 [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]


<PAGE>   27

                                    MILLENNIAL HOLDINGS, LLC

                                     /s/ G. JACKSON TANKERSLEY
                                    --------------------------------------------
                                    G. Jackson Tankersley, Jr., Managing Member


 [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]


<PAGE>   28

                                    MUSHTARAK LIMITED

                                    By: /s/ Abdul Wahab S. Albaptain
                                       -----------------------------------------
                                    Name:  Abdul Wahab S. Albaptain
                                         ---------------------------------------
                                    Title:  Director
                                          --------------------------------------


 [SIGNATURE PAGE TO SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]