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                                                                    EXHIBIT 4(u)

                              SILICON VALLEY BANK
                         REGISTRATION RIGHTS AGREEMENT


     THIS REGISTRATION RIGHTS AGREEMENT is entered into as of July 31, 2000, by
and between Silicon Valley Bank ("Purchaser") and the Company whose name appears
on the last page of this Agreement.

                                   RECITALS
                                   --------

     A.   Concurrently with the execution of this Agreement, the Purchaser is
purchasing from the Company a Warrant to Purchase Stock (the "Warrant") pursuant
to which Purchaser has the right to acquire from the Company the Shares (as
defined in the Warrant).

     B.   By this Agreement, the Purchaser and the Company desire to set forth
the registration rights of the Shares all as provided herein.

          NOW, THEREFORE, in consideration of the mutual promises, covenants and
conditions hereinafter set forth, the parties hereto mutually agree as follows:

     1.   Registration Rights. The Company covenants and agrees as follows:
          -------------------

          1.1   Definitions.  For purposes of this Section 1:
                -----------

                (a)  The term "register," "registered," and "registration" refer
to a registration effected by preparing and filing a registration statement or
similar document in compliance with the Securities Act of 1933, as amended (the
"Securities Act"), and the declaration or ordering of effectiveness of such
registration statement or document;

                (b)  The term "Registrable Securities" means (i) the Shares (if
Common Stock) or all shares of Common Stock of the Company issuable or issued
upon conversion of the Shares and (ii) any Common Stock of the Company issued as
(or issuable upon the conversion or exercise of any warrant, right or other
security which is issued as) a dividend or other distribution with respect to,
or in exchange for or in replacement of, any stock referred to in (i);
provided that with respect to any Registrable Securities, such securities shall
cease to be Registrable Securities when they (i) have been distributed to the
public pursuant to a registered offering under the Securities Act or sold to the
public through a broker, dealer or market maker in compliance with Rule 144
under the Securities Act (or any similar rule then in force), (ii) could be sold
(taking into account volume limitations) to the public through a broker, dealer
or market maker in compliance with Rule 144 under the Securities Act (or any
similar rule then in force), or (iii) have been repurchased by the Company.

                (c)  The terms "Holder" or "Holders" means the Purchaser or
qualifying transferees under subsection 1.8 hereof who hold Registrable
Securities.
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                (d)  The term "SEC" means the Securities and Exchange
Commission.

          1.2   Company Registration.
                --------------------

                (a)  Registration. If at any time or from time to time, the
                     ------------
Company shall determine to register any of its securities, for its own account
or the account of any of its shareholders, other than a registration on Form S-1
or S-8 relating solely to employee stock option or purchase plans, or a
registration on Form S-4 relating solely to an SEC Rule 145 transaction, or a
registration on any other form (other than Form S-1, S-2, S-3 or S-18, or their
successor forms) or any successor to such forms, which does not include
substantially the same information as would be required to be included in a
registration statement covering the sale of Registrable Securities, the Company
will:

                     (i)   promptly give to each Holder written notice
thereof (which shall include a list of the jurisdictions in which the Company
intends to attempt to qualify such securities under the applicable blue sky or
other state securities laws); and

                     (ii)  include in such registration (and compliance), and
in any underwriting involved therein, all the Registrable Securities specified
in a written request or requests, made within 30 days after receipt of such
written notice from the Company, by any Holder or Holders, except as set forth
in subsection 1.2(b) below.

                (b)  Underwriting. If the registration of which the Company
                     ------------
gives notice is for a registered public offering involving an underwriting, the
Company shall so advise the Holders as a part of the written notice given
pursuant to subsection 1.2(a)(i). In such event the right of any Holder to
registration pursuant to this subsection 1.2 shall be conditioned upon such
Holder's participation in such underwriting and the inclusion of such Holder's
Registrable Securities in the underwriting to the extent provided herein. All
Holders proposing to distribute their securities through such underwriting shall
(together with the Company and the other shareholders distributing their
securities through such underwriting) enter into an underwriting agreement in
customary form with the underwriter or underwriters selected for such
underwriting by the Company. (c) (1) If a registration described in this
Section 1 is an underwritten primary registration on behalf of the Company, and
the managing underwriters advise the Company in writing that in their opinion
the number of securities requested to be included in such registration exceeds
the number which can be sold in an orderly manner in such offering within a
price range acceptable to the Company, the Company shall include in such
registration (i) first, the securities the Company proposes to sell, (ii)
second, to the securities of any holders of the Company's securities with prior
contractual rights to have such securities so included within such priority,
(iii) third, the Registrable Securities requested to be included in such
registration, pro rata among the holders of such Registrable Securities on the
basis of the number of shares owned by each such holder, and (iv) fourth, other
securities requested to be included in such registration.

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               (2)  If a registration described in this Section 1 is an
underwritten secondary registration on behalf of holders of the Company's
securities, and the managing underwriters advise the Company in writing that in
their opinion the number of securities requested to be included in such
registration exceeds the number which can be sold in an orderly manner in such
offering within a price range acceptable to the holders initially requesting
such registration, the Company shall include in such registration (i) first, the
securities requested to be included therein by the holders requesting such
registration, (ii) second, to the securities of any holders of the Company's
securities with prior contractual rights to have such securities so included
within such priority, (iii) third, the Registrable Securities requested to be
included in such registration, pro rata among the holders of such Registrable
Securities on the basis of the number of shares owned by each such holder, and
(iv) fourth, other securities requested to be included in such registration.

               (d)  Each holder of Registrable Securities shall not effect any
public sale or distribution (including sales pursuant to Rule 144) of equity
securities of the Company, or any securities convertible into or exchangeable or
exercisable for such securities, during the seven days prior to the 90-day
period beginning on the effective date of any other registration in which
Registrable Securities are included (in each case, except as part of such
underwritten registration), unless in each case the underwriters managing the
registered public offering otherwise agree.

               (e)  Each holder of Registrable Securities agrees that upon
receipt of any notice from the Company of the occurrence of an event of the kind
described in Section 1.4(f) hereof, such holder will immediately discontinue
disposition of Registrable Securities until such holder's receipt of copies of a
supplemented or amended prospectus identified by the Company as necessary to
correct any untrue statement of a material fact in the prospectus relating to
the applicable registration statement, as then in effect, or to correct an
omission of a statement or a material fact required to be stated in such
prospectus, and, if so directed by the Company, such holder will deliver to the
Company (at the Company's expense) all copies, other than permanent file copies
then in the holder's possession, of the prospectus covering such Registrable
Securities current at the time of receipt of such notice.

               (f)  The Company represents and warrants to Purchaser that once
the securities of the Company that are currently the subject of an S-1
Registration have been registered for sale, there will not be any other holders
of the Company's securities with contractual rights having priority that would
fall within the category of those holders described in Section 1.2(c)(1)(ii) and
Section 1.2(c)(2)(ii) above.

          1.3  Expenses of Registration. All expenses incurred in connection
               ------------------------
with any registration, qualification or compliance pursuant to this Section 1
including without limitation, all registration, filing and qualification fees,
printing expenses, fees and disbursements of counsel for the Company and
expenses of any special audits incidental to or required by such registration,
shall be borne by the Company except the Company shall not be required to pay
underwriters' fees, discounts or commissions relating to Registrable Securities.
All expenses of any registered

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offering not otherwise borne by the Company shall be borne pro rata among the
Holders participating in the offering and the Company.

          1.4  Registration Procedures. In the case of each registration,
               -----------------------
qualification or compliance effected by the Company pursuant to this
Registration Rights Agreement, the Company will keep each Holder participating
therein advised in writing as to the initiation of each registration,
qualification and compliance and as to the completion thereof. Except as
otherwise provided in subsection 1.3, at its expense the Company will:

               (a)  Prepare and file with the SEC a registration statement with
respect to such Registrable Securities and use its best efforts to cause such
registration statement to become effective, and, upon the request of the Holders
of a majority of the Registrable Securities registered thereunder, keep such
registration statement effective for up to 120 days or until the Registrable
Securities are sold.

               (b)  Prepare and file with the SEC such amendments and
supplements to such registration statement and the prospectus used in connection
with such registration statement as may be necessary to comply with the
provisions of the Securities Act with respect to the disposition of all
securities covered by such registration statement.

               (c)  Furnish to the Holders such numbers of copies of a
prospectus, including a preliminary prospectus, in conformity with the
requirements of the Securities Act, and such other documents as they may
reasonably request in order to facilitate the disposition of Registrable
Securities owned by them.

               (d)  Use its best efforts to register and qualify the securities
covered by such registration statement under such other securities or Blue Sky
laws of such jurisdictions as shall be reasonably requested by the Holders,
provided that the Company shall not be required in connection therewith or as a
condition thereto to (i) qualify to do business, (ii) to file a general consent
to service of process in any such states or jurisdictions, or (iii) subject
itself to taxation in any such jurisdiction.

               (e)  In the event of any underwritten public offering, enter into
and perform its obligations under an underwriting agreement, in usual and
customary form, with the managing underwriter of such offering. Each Holder
participating in such underwriting shall also enter into and perform its
obligations under such an agreement.

               (f)  Notify each Holder of Registrable Securities covered by such
registration statement at any time when a prospectus relating thereto is
required to be delivered under the Securities Act or the happening of any event
as a result of which the prospectus included in such registration statement, as
then in effect, includes an untrue statement of a

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material fact or omits 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 then existing.

          1.5  Indemnification.
               ---------------

               (a)  The Company will indemnify each Holder of Registrable
Securities and each of its officers, directors and partners, and each person
controlling such Holder, with respect to which such registration, qualification
or compliance has been effected pursuant to this Rights Agreement, and each
underwriter, if any, and each person who controls any underwriter of the
Registrable Securities held by or issuable to such Holder, against all claims,
losses, expenses, damages and liabilities (or actions in respect thereto)
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 statement therein not misleading, or any
violation or alleged violation by the Company of the Securities Act, the
Securities Exchange Act of 1934, as amended, ("Exchange Act") or any state
securities law applicable to the Company or any rule or regulation promulgated
under the Securities Act, the Exchange Act or any such state law and relating to
action or inaction required of the Company in connection with any such
registration, qualification of 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,
within a reasonable amount of time after incurred for any reasonable legal and
any other expenses incurred in connection with investigating, defending or
settling any such claim, loss, damage, liability or action; provided, however,
that the indemnity agreement contained in this subsection 1.5(a) shall not apply
to amounts paid in settlement of any such claim, loss, damage, liability, or
action if such settlement is effected without the consent of the Company (which
consent shall not be unreasonably withheld); and provided further, that the
Company will not be liable in any such case to the extent that any such claim,
loss, damage or liability arises out of or is based on any untrue statement or
omission based upon written information furnished to the Company by an
instrument duly executed by such Holder or underwriter specifically for use
therein.

               (b)  Each Holder will, if Registrable Securities held by or
issuable to such Holder are included in the securities as to which such
registration, qualification or compliance is being effected, indemnify the
Company, each of its directors and officers, each underwriter, if any, of the
Company's securities covered by such a registration statement, each person who
controls the Company within the meaning of the Securities Act, and each other
such Holder, each of its officers, directors and partners and each person
controlling such Holder, against all claims, losses, expenses, 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 such registration statement, prospectus, offering circular or other
document, or 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, and will reimburse the Company, such Holders, such directors,
officers, partners, persons or underwriters for any reasonable legal or any
other expenses incurred in connection with investigating, defending or settling
any such claim,

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<PAGE>

loss, damage, liability or action, in each case to the extent, but only to the
extent, that such untrue statement (or alleged untrue statement) or omission (or
alleged omission) is made in such registration statement, prospectus, offering
circular or other document in reliance upon and in conformity with written
information furnished to the Company by an instrument duly executed by such
Holder specifically for use therein; provided, however, that the indemnity
agreement contained in this subsection 1.5(b) shall not apply to amounts paid in
settlement of any such claim, loss, damage, liability or action if such
settlement is effected without the consent of the Holder, (which consent shall
not be unreasonably withheld); and provided further, that the total amount for
which any Holder shall be liable under this subsection 1.5(b) shall not in any
event exceed the aggregate proceeds received by such Holder from the sale of
Registrable Securities held by such Holder in such registration.

               (c)  Each party entitled to indemnification under this subsection
1.5 (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, and shall
permit the Indemnifying Party to assume the defense of any such claim or any
litigation resulting therefrom; provided that counsel for the Indemnifying
Party, who shall conduct the defense of such claim or litigation, shall be
approved by the Indemnified Party (whose approval shall not be unreasonably
withheld), and the Indemnified Party may participate in such defense at such
party's expense; and provided further, that the failure of any Indemnified Party
to give notice as provided herein shall not relieve the Indemnifying Party of
its obligations hereunder, unless such failure resulted in prejudice to the
Indemnifying Party; and provided further, that an Indemnified Party (together
with all other Indemnified Parties which may be represented without conflict by
one counsel) shall have the right to retain one separate counsel, with the fees
and expenses to be paid by the Indemnifying Party, if representation of such
Indemnified Party by the counsel retained by the Indemnifying Party would be
inappropriate due to actual or potential differing interests between such
Indemnified Party and any other party represented by such counsel in such
proceeding. 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.

          1.6  Information by Holder. Any Holder or Holders of Registrable
               ---------------------
Securities included in any registration shall promptly furnish to the Company
such information regarding such Holder or Holders and the distribution proposed
by such Holder or Holders as the Company may request in writing and as shall be
required in connection with any registration, qualification or compliance
referred to herein.

          1.7  Rule 144 Reporting. With a view to making available to Holders
               ------------------
the benefits of certain rules and regulations of the SEC which may permit the
sale of the Registrable Securities to the public without registration, the
Company agrees at all times to:

               (a)  make and keep public information available, as those terms
are understood and defined in SEC Rule 144, after 90 days after the effective
date of the first registration filed by the Company for an offering of its
securities to the general public;

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<PAGE>

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

               (c)  so long as a Holder owns any Registrable Securities, to
furnish to such Holder forthwith upon request a written statement by the Company
as to its compliance with the 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), 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 the Holder may reasonably request in complying with any rule
or regulation of the SEC allowing the Holder to sell any such securities without
registration.

          1.8  Transfer of Registration Rights. Holders' rights to cause the
               -------------------------------
Company to register their securities and keep information available, granted to
them by the Company under subsections 1.2 and 1.7 may be assigned to a
transferee or assignee of a Holder's Registrable Securities not sold to the
public, provided, that the Company is given written notice by such Holder at the
time of or within a reasonable time after said transfer, stating the name and
address of said transferee or assignee and identifying the securities with
respect to which such registration rights are being assigned. The Company may
prohibit the transfer of any Holders' rights under this subsection 1.8 to any
proposed transferee or assignee who the Company reasonably believes is a
competitor of the Company.

     2.    General.
           -------

          2.1  Waivers and Amendments. With the written consent of the
               ----------------------
record or beneficial holders of at least a majority of the Registrable
Securities, the obligations of the Company and the rights of the Holders of the
Registrable Securities under this agreement may be waived (either generally or
in a particular instance, either retroactively or prospectively, and either for
a specified period of time or indefinitely), and with the same consent the
Company, when authorized by resolution of its Board of Directors, may enter into
a supplementary agreement for the purpose of adding any provisions to or
changing in any manner or eliminating any of the provisions of this Agreement;
provided, however, that no such modification, amendment or waiver shall reduce
the aforesaid percentage of Registrable Securities without the consent of all of
the Holders of the Registrable Securities. Upon the effectuation of each such
waiver, consent, agreement of amendment or modification, the Company shall
promptly give written notice thereof to the record holders of the Registrable
Securities who have not previously consented thereto in writing. This Agreement
or any provision hereof may be changed, waived, discharged or terminated only by
a statement in writing signed by the party against which enforcement of the
change, waiver, discharge or termination is sought, except to the extent
provided in this subsection 2.1.

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          2.2  Governing Law. This Agreement shall be governed in all respects
               -------------
by the laws of the State of California as such laws are applied to agreements
between California residents entered into and to be performed entirely within
California.

          2.3  Successors and Assigns. Except as otherwise expressly provided
               ----------------------
herein, the provisions hereof shall inure to the benefit of, and be binding
upon, the successors, assigns, heirs, executors and administrators of the
parties hereto.

          2.4  Entire Agreement. Except as set forth below, this Agreement and
               ----------------
the other documents delivered pursuant hereto constitute the full and entire
understanding and agreement between the parties with regard to the subjects
hereof and thereof.

          2.5  Notices, etc. All notices and other communications required or
               -------
permitted hereunder shall be in writing and shall be mailed by first class mail,
postage prepaid, certified or registered mail, return receipt requested,
addressed (a) if to Holder, at such Holder's address as set forth below, or at
such other address as such Holder shall have furnished to the Company in
writing, or (b) if to the Company, at the Company's address set forth below, or
at such other address as the Company shall have furnished to the Holder in
writing.

          2.6  Severability. In case any provision of this Agreement shall be
               ------------
invalid, illegal, or unenforceable, the validity, legality and enforceability of
the remaining provisions of this Agreement or any provision of the other
Agreements shall not in any way be affected or impaired thereby.

          2.7  Titles and Subtitles. The titles of the sections and subsections
               --------------------
of this Agreement are for convenience of reference only and are not to be
considered in construing this Agreement.

          2.8  Counterparts. This Agreement may be executed in any number of
               ------------
counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.


PURCHASER                                      COMPANY

SILICON VALLEY BANK                            THE NETPLEX GROUP, INC.



       /s/ Milad Hanna                                 /s/ Peter J. Russo
By: __________________________________         By:  ____________________________
Name:                                          Name:

         Milad Hanna                                  Peter J. Russo
________________________________               _____________________________
           (print)                                     (print)

Title:                                         Title:   Chairman of the Board,
                                                       President or Vice
                                                       President
         Vice President
________________________________
Address:  3003 Tasman Drive                    Address:  1800 Robert Fulton
       Santa Clara, CA 95054                           Drive, Suite 250 Reston,
                                                       VA 20191

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