<PAGE>   1

EXHIBIT 10.1
                                NETERGY NETWORKS

                          REGISTRATION RIGHTS AGREEMENT


       This Registration Rights Agreement (together with any amendments and
exhibits thereto, the "AGREEMENT") is made as of the 30th day of June, 2000,
between 8x8, Inc., a Delaware corporation doing business as Netergy Networks
(together with any successors "NETERGY"), and the parties listed on Exhibit A
hereto, pursuant to that certain Share Exchange Agreement, dated as of May 19,
2000 among Netergy, UForce Inc., and the Security Holders named therein (the
"SHARE EXCHANGE AGREEMENT"), and pursuant to the Termination Agreement and
Mutual Release dated as of May 19, 2000 by and among Netergy, Logibro Inc. and
UForce Inc.

       1. DEFINITIONS. As used in this Agreement:

               (a) "CLOSING DATE" means the Closing Date as defined in Section
1.1 of the Share Exchange Agreement.

               (b) "EFFECTIVE DATE" shall mean the date upon which a
registration statement filed pursuant to Section 2 of this Agreement shall have
been declared effective by the SEC.

               (c) "EXCHANGE ACT" means the Securities Exchange Act of 1934, as
amended, and the rules and regulations of the SEC promulgated thereunder.

               (d) "FORM S-3" means such form under the Securities Act as in
effect on the date hereof or any registration form under the Securities Act
subsequently adopted by the SEC which similarly permits inclusion or
incorporation of substantial information by reference to other documents filed
by Netergy with the SEC.

               (e) "HOLDERS" shall mean persons holding Registrable Securities.

               (f) "IMMEDIATE FAMILY" of an individual shall mean a spouse of
such individual, or a parent, sibling or lineal descendant of such individual or
his or her spouse, whether by adoption or otherwise.

               (g) "LOCKUP SHARES" means those Registrable Securities that are
subject to lockup provisions pursuant to the Share Exchange Agreement or any
stock restriction agreement the form of which is listed as an exhibit to the
Share Exchange Agreement (the "LOCKUP PROVISIONS").

               (h) "MAJORITY HOLDERS" means those Holders or their designated
representative, who together own at least a majority of the Registrable
Securities, but including SGF Tech Inc. or any direct or indirect subsidiaries
thereof (including 9091-1215 Quebec, Inc.) holding Registrable Securities.

<PAGE>   2

               (i) "MATERIAL EVENT" means the happening of any event during the
period that a registration statement described in Section 2 hereof is required
to be effective as a result of which, in the reasonable judgment of Netergy,
such registration statement or the related prospectus contains or may contain
any untrue statement of a material fact or omits or may omit to state any
material fact required to be stated therein or necessary to make the statements
therein not misleading.

               (j) "OPTION SHARES" means the Parent Shares purchasable or
purchased from time to time under the Company Options assumed by Netergy or
Replacement Options issued by Netergy as of the Closing Date, together with all
additional securities receivable or received in payment of dividends or
distributions on or splits of those securities received as a result of
adjustments provided for in the related Option Agreements.

               (k) "REGISTRABLE SECURITIES" means the Parent Shares issued to
the Security Holders or to Logibro Inc., or issuable to the Security Holders
upon exchange of the Exchangeable Shares (including the Indemnification Shares),
together with all additional securities receivable or received in payment of
dividends or distributions on or splits of those securities; provided, however,
that such securities shall only be treated as Registrable Securities if and so
long as they have not been (A) sold to or through a broker or dealer or
underwriter in a public distribution or a public securities transaction, or (B)
sold or are, in the opinion of counsel for Parent, available for sale in a
single transaction exempt from the registration and prospectus delivery
requirements of the Securities Act so that all transfer restrictions and
restrictive legends with respect thereto may be removed prior to or upon the
consummation of such sale.

               (l) "SEC" means the Securities and Exchange Commission.

               (m) "SECURITIES ACT" means the Securities Act of 1933, as
amended, and the rules and regulations of the SEC promulgated thereunder.

               Terms not otherwise defined herein have the meanings given to
them in the Share Exchange Agreement.

       2. REGISTRATION.

               (b) Form S-3 Registration. Netergy shall use commercially
reasonable efforts to cause the Registrable Securities issued or issuable to the
Holders to be registered under the Securities Act no later than 120 days after
the Closing Date, so as to permit the resale thereof, and in connection
therewith shall prepare and file with the SEC and shall use commercially
reasonable efforts to cause to become effective, a Form S-3 covering the
Registrable Securities; provided, however, that the Holders shall provide all
such information and materials relating to the Holders as may be required to be
disclosed pursuant to applicable SEC rules and regulations, and take all such
commercially reasonable action as may be required in order to permit Netergy to
comply with all the applicable requirements of the SEC in order to cause the
Form S-3 or other registration statement required to be filed pursuant to this
Section 2 to be declared effective by the SEC, such provision of information and
materials to be a condition precedent to the obligations of Netergy pursuant to
this Agreement and the Share Exchange Agreement.



                                      -10-
<PAGE>   3

               (c) Demand Registration. In the event that (i) a Form S-3
covering the Registrable Securities is not effective within 120 days after the
Closing Date, (ii) Netergy ceases to be eligible to use Form S-3 or (iii) Rule
144 ceases to be available for the resale of the Registrable Securities under
the Securities Act, then if Netergy shall receive from either (a) the Majority
Holders or (b) SGF Tech Inc. (or its direct or indirect subsidiary holding
Registrable Securities), a written request that Netergy effect a registration,
qualification or compliance with respect to Registrable Securities constituting
at least 25% of the Registrable Securities, Netergy shall within 120 days of
such request, use its commercially reasonable efforts to effect such
registration under the Securities Act (other than pursuant to a registration
statement on Form S-4 or S-8 or any successor thereto) as may be so requested
and as would permit or facilitate the sale and distribution of all of such
Registrable Securities specified in such request; provided, however, that
Netergy shall not be obligated to effect (i) more than two (2) such
registrations in the aggregate being agreed that only one of such requests may
be made by each of (1) the Majority Holders and (2) SGF Tech Inc. (or its
subsidiaries) and (ii) any registration under the Securities Act except in
accordance with the provisions of this Agreement. The offerings made pursuant to
such registrations under this Section 2 shall not be underwritten.

               (d) Form S-8 Registration. Within 60 days after the Closing Date,
Netergy shall prepare and file a registration statement on Form S-8 registering
the Option Shares under the Securities Act.

               (e) Release of Registrable Securities from Lockup Provisions. In
the event that any Lockup Shares are released from Lockup Provisions prior to
120 days after the Closing Date, then Netergy shall, commencing at the time of
the release of such Lockup Shares, use commercially reasonable efforts to cause
the Form S-3 to become effective as soon as practicable rather than within 120
days after the Closing Date; but in any case no later than 120 days after the
Closing Date.

        3. POSTPONEMENT OF REGISTRATION.

               (b) Registration. Notwithstanding Section 2 above, Netergy shall
be entitled to postpone the declaration of effectiveness of any registration
statement prepared and filed pursuant to Section 2 for a reasonable period of
time, but not in excess of 60 calendar days after the applicable deadline, if
the Board of Directors of Netergy, acting in good faith, determines that there
exists a Material Event.

               (c) Material Event. The Holders agree that, upon receipt of any
notice from Netergy of the happening of a Material Event, the Holders will
forthwith discontinue any disposition of Registrable Securities or Option Shares
pursuant to any registration statement described in Section 2 until the Holders'
receipt of copies of supplemented or amended prospectuses prepared by Netergy
(which Netergy will use its commercially reasonable efforts to prepare and file
promptly), and, if so directed by Netergy, the Holders will deliver to Netergy
all copies in their possession, other than permanent file copies then in the
Holders' possession, of the prospectus covering such Registrable Securities
current at the time of receipt of such notice. Holders that are "affiliates" of
Netergy within the meaning of Rule 144(a)(1) agree to discontinue disposition of
the Registrable Securities during any restricted trading periods imposed on
affiliates by Netergy's Insider Trading Compliance Program.



                                      -11-
<PAGE>   4

        4. OBLIGATIONS OF NETERGY.

               (a) Except as set forth in Sections 2 and 3, Netergy shall (i)
prepare and file with the SEC the registration statement in accordance with
Section 2 hereof with respect to the shares of Registrable Securities and the
Option Shares and shall use commercially reasonable efforts to cause such
registration statement to become effective as provided in Section 2 and to keep
such registration statement described in Section 2(a) and 2(b) continuously
effective until the earlier to occur of (A) the sale of all of the Registrable
Securities so registered and (B) the first anniversary of the Effective Date;
(ii) furnish to the Holders such number of copies of any prospectus (including
any preliminary prospectus and any amended or supplemented prospectus), as the
Holders may reasonably request in order to effect the offering and sale of the
Registrable Securities and Option Shares to be offered and sold, but only while
Netergy shall be required under the provisions hereof to cause such registration
statement to remain current; (iii) use its commercially reasonable efforts to
register or qualify the shares of the Registrable Securities and Option Shares
covered by such registration statement under the securities or "blue sky" laws
of such jurisdictions as the Holders shall reasonably request (provided that
Netergy shall not be required in connection therewith or as a condition thereto
to qualify to do business or to file a general consent to service of process in
any such jurisdiction where it has not been qualified), and do any and all other
acts or things which may be reasonably necessary or advisable to enable the
Holders to consummate the public sale or other disposition of the Registrable
Securities and Option Shares in such jurisdictions; (iv) cause all such
Registrable Securities and Option Shares to be listed on each securities
exchange or National Association of Securities Dealers, Inc. Automated Quotation
System on which similar securities issued by Netergy are then listed; (v) notify
the Holders of any Material Event; (vi) so long as any registration statement
described in Section 2 remains effective, promptly prepare, file and furnish to
the Holders 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 the Registrable Securities and Option Shares, 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 then existing; (vii)
notify the Holders promptly after it shall receive notice thereof, of the date
and time any registration statement and each post-effective amendment thereto
has become effective or a supplement to any prospectus forming a part of such
registration statement has been filed; (viii) notify the Holders promptly of any
request by the SEC for the amending or supplementing of such registration
statement or prospectus or for additional information; (ix) advise the Holders
promptly after it shall receive notice or obtain knowledge thereof, of the
issuance of any stop order by the SEC suspending the effectiveness of any
registration statement or the initiation or threatening of any proceeding for
that purpose and promptly use commercially reasonable efforts to prevent the
issuance of any stop order or to obtain its withdrawal if such stop order should
be issued, and (x) furnish copies of prospectuses to any national securities
exchange upon which the Registrable Securities are listed in compliance with
Rule 153 adopted pursuant to the Securities Act, or any similar rule as in
effect from time to time, so as to enable all the Holders to rely on such Rule
for sales of Registrable Securities through the facilities of such national
securities exchange.



                                      -12-
<PAGE>   5

               (b) Netergy shall comply with all of the reporting requirements
of the Exchange Act applicable to it and shall comply with all other public
information reporting requirements of the SEC that are conditions to the
availability of Rule 144 for the sale of the Registrable Securities and/or the
Option Shares. Netergy shall cooperate with the Holders in supplying such
information as may be necessary for the Holders to complete and file any
information reporting forms presently or hereafter required by the SEC as a
condition to the availability of Rule 144.

               (c) Netergy shall not, directly or indirectly, enter into any
merger, consolidation or reorganization in which Netergy shall not be the
surviving corporation unless the surviving corporation shall, prior to such
merger, consolidation or reorganization, agree in writing to assume the
obligations of Netergy under this Agreement, and for that purpose references
hereunder to "Registrable Securities" and "Option Shares" shall be deemed to
include the common stock, if any, that Holders would be entitled to receive in
exchange for their securities under any such merger, consolidation or
reorganization; provided, however, that, to the extent Holders receive
securities that are by their terms convertible into common stock of the issuer
thereof, then only such shares of common stock as are issued or issuable upon
conversion of said convertible securities shall be included within the
definition of "Registrable Securities" and "Option Shares".

        5. EXPENSES. Netergy shall pay the expenses incurred by Netergy in
connection with any registration of Registrable Securities and/or Option Shares
pursuant to this Agreement including all SEC, NASD and "blue sky" registration
and filing fees, printing expenses, transfer agents' and registrars' fees, and
the reasonable fees and disbursements of Netergy's outside counsel and
independent accountants. The Holders shall be responsible for all commissions
and transfer taxes, as well as any other expenses incurred by the Holders, other
than the reasonable fees and disbursements of counsel to the Holders not
exceeding $10,000 which shall be paid by Netergy.

        6. INDEMNIFICATION. In the event of any offering registered pursuant to
this Agreement:

               (b) Netergy will indemnify and hold harmless each Holder and, if
an entity, each of the Holder's directors and officers and each person who
controls the Holder within the meaning of Section 15 of the Securities Act, with
respect to any registration or qualification effected pursuant to this
Agreement, against all expenses, claims, losses, damages and liabilities (or
actions in respect thereof), including any of the foregoing incurred in
settlement of any litigation, commenced or threatened, to which any of the
foregoing persons may be subject under the Securities Act or otherwise arising
out of or based on any untrue statement (or alleged untrue statement) of a
material fact contained in any registration statement, or any amendment or
supplement thereto, or prospectus related thereto, incident to any such
registration or qualification, or based on any omission (or alleged omission) to
state therein a material fact required to be stated therein or necessary to make
the statements therein, in light of the circumstances in which they are made,
not misleading, or any violation by Netergy of any rule or regulation
promulgated under the Securities Act, or state securities laws, or common law,
applicable to Netergy in connection with any such registration or qualification,
and will reimburse such Holder and each such director, officer or control
persons, for any legal and any other expenses reasonably incurred by any of them
in connection with investigating, preparing or defending any such claim, loss,
damage, liability or action, provided, however, that Netergy will not be liable
in any such case (i) to the extent that any such claim, loss,


                                      -13-
<PAGE>   6
damage, liability or expense arises out of or is based in any untrue statement
or omission or alleged untrue statement or omission, made in reliance upon and
in conformity with written information furnished to Netergy by an instrument
duly executed by such Holder or any person who controls the Holder and stated to
be specifically for use therein or (ii) if a Holder disposes of Registrable
Securities or Option Shares in breach of the first sentence of Section 3(b).

               (c) Each Holder of Registrable Securities and/or Option Shares
will severally and not jointly indemnify and hold harmless Netergy, each of its
directors and officers and each person who controls Netergy within the meaning
of Section 15 of the Securities Act, against all claims, losses, damages and
liabilities (or actions in respect thereof) arising out of or based on any
untrue statement (or alleged untrue statement) or a material fact contained in
any registration statement, or any amendment or supplement thereto, or
prospectus related 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 not misleading, but only to the extent, that such untrue
statement (or alleged untrue statement) or omission (or alleged omission) is
made in such registration statement or prospectus in reliance upon and in
conformity with written information furnished to Netergy by an instrument duly
executed by such Holder and stated to be specifically for use therein and will
reimburse Netergy, the remaining Holders, such directors, officers, or control
persons for any legal or any other expenses reasonably incurred in connection
with investigating or defending any such claim, loss, damage, liability or
action, but only to the extent, that such untrue statement (or alleged untrue
statement) or omission (or alleged omission) is made in such registration
statement or prospectus, in reliance upon and in conformity with written
information furnished to Netergy by an instrument duly executed by such Holder
and stated to be specifically for use therein; provided, however, that the
maximum amount of liability in respect of such indemnification shall be in
proportion to and limited to, in the case of each Holder of Registrable
Securities and/or Option Shares, an amount equal to the net proceeds actually
received by such Holder from the sale of Registrable Securities and/or Option
Shares effected pursuant to such registration.

               (d) Each party entitled to indemnification under this Section 6
(the "INDEMNIFIED PARTY") shall give notice to the party required to provide
indemnification (the "INDEMNIFYING PARTY") promptly after such Indemnified Party
has notice 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, 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 responsible for any legal or other expenses
subsequently incurred by the Indemnified Party in connection with the defense
thereof; provided, however, that, if any Indemnified Party shall have reasonably
concluded that there may be one or more legal or equitable defenses available to
such Indemnified Party which are additional to or conflict with those available
to the Indemnifying Party, or that such claim or litigation involves or could
have an effect upon matters beyond the scope of the indemnity agreement provided
in this Section 6, then the Indemnifying Party shall not have the right to
assume the defense of such action on behalf of such Indemnified Party and such
Indemnifying Party shall reimburse such Indemnified Party and any Person
controlling such Indemnified Party for that portion of the fees and expenses of



                                      -14-
<PAGE>   7

any counsel retained by the Indemnified Party which is reasonably related to the
matters covered by the indemnity agreement provided in this Section 6. 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
under this Agreement, except to the extent, but only to the extent, that the
Indemnifying Party's ability to defend against such claim or litigation is
impaired as a result of such failure to give notice. 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 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. Whether or not the defense of any claim
or action is assumed by the Indemnifying Party, such Indemnifying Party will not
be subject to any liability for any settlement without its consent.

               (e) If the indemnification provided for in this Section 6 is held
by a court of competent jurisdiction to be unavailable to an Indemnified Party
with respect to any loss, claim, damage, liability or action referred to herein,
then the Indemnifying Party, in lieu of indemnifying such Indemnified Party
hereunder, shall contribute to the amounts paid or payable by such Indemnified
Party as a result of such loss, claim, damage, liability or action in such
proportion as is appropriate to reflect the relative fault of the Indemnifying
Party on the one hand and of the Indemnified Party on the other, in connection
with the statements or omissions which resulted in such loss, claim, damage,
liability or action as well as any other relevant equitable considerations;
provided, however, that, if the circumstances described in either proviso of
Section 6(a) apply to the Indemnified Party, then the Indemnifying Party shall
not be obligated to contribute with respect to such loss, claim, damage,
liability or action to the extent set forth in such proviso. The relative fault
of the Indemnifying Party and of the Indemnified Party 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 by the Indemnified
Party and the parties' relative intent, knowledge, access to information and
opportunity to correct or prevent such statement or omission.

               (f) Netergy and the Holders agree that it would not be just and
equitable if contribution pursuant to Section 6(d) were determined by pro rata
allocation (even if the Holders were treated as one entity for such purpose) or
by any other method of allocation that does not take account of the equitable
considerations referred to in Sections 6(c) and 6(d). The amount paid or payable
by an Indemnified Party as a result of the losses, claims, damages and
liabilities referred to in subsection (d) of this Section 6 shall be deemed to
include, subject to the limitations set forth above, any legal or other expenses
reasonably incurred by such Indemnified Party in connection with investigating
or defending any such action or claim.

               (g) The obligations of Netergy and any of the Holders under this
Section 6 shall survive the completion of any offering of stock in a
registration statement under this Agreement.

        7. RESTRICTIONS ON TRANSFER.



                                      -15-
<PAGE>   8

               (b) The Holders understand that the Registrable Securities issued
in connection with the Share Exchange Agreement have been or will be issued in a
transaction exempt from the registration requirements of the Securities Act and
shall not be transferable except in accordance with the terms of Section 7(b) of
this Agreement and (A) in accordance with the registration statement filed with
the SEC, in which case Holder must comply with the requirement of delivering a
current prospectus, (B) in accordance with Rule 144, or (C) pursuant to an
exemption from the registration requirements of the Securities Act. Netergy
shall be entitled to give stop transfer instructions to its transfer agent with
respect to the Registrable Securities in order to enforce the foregoing
restrictions.

               (c) Each Holder will not make any offering, sale, short sale or
other disposition of Lockup Shares, directly or indirectly, without (i) the
prior written consent of Netergy, or (ii) except in accordance with the Lockup
Provisions to which it is a party.

        8. RESTRICTIVE LEGENDS. Each certificate representing Registrable
Securities shall bear substantially the following legends (in addition to any
legends required under applicable securities laws):

        THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
        1933. THE HOLDER HEREOF MAY NOT ENGAGE IN HEDGING TRANSACTIONS WITH
        RESPECT TO THESE SECURITIES, NOR MAY THESE SECURITIES BE SOLD, OFFERED
        FOR SALE, PLEDGED OR HYPOTHECATED IN THE ABSENCE OF COMPLIANCE WITH
        REGULATION S UNDER THE ACT, A REGISTRATION STATEMENT IN EFFECT WITH
        RESPECT TO THE SECURITIES UNDER SUCH ACT OR AN OPINION OF COUNSEL
        SATISFACTORY TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED OR
        UNLESS SOLD PURSUANT TO RULE 144 OF SUCH ACT.

        ADDITIONALLY, THE TRANSFER OF THE SHARES REPRESENTED BY THIS CERTIFICATE
        IS SUBJECT TO CERTAIN RESTRICTIONS SPECIFIED IN A REGISTRATION RIGHTS
        AGREEMENT AMONG THE ISSUER AND CERTAIN CURRENT AND FORMER SECURITY
        HOLDERS OF UFORCE COMPANY DATED JUNE 30, 2000 (THE "AGREEMENT"), AND NO
        TRANSFER OF SHARES SHALL BE VALID OR EFFECTIVE ABSENT COMPLIANCE WITH
        SUCH RESTRICTIONS. COPIES OF THE AGREEMENT MAY BE OBTAINED AT NO COST BY
        WRITTEN REQUEST MADE BY THE REGISTERED HOLDER OF THIS CERTIFICATE TO THE
        SECRETARY OF THE COMPANY.

        The legends contained in this Section 8 shall be removed from a
certificate in connection with any sale in compliance with the terms of this
Agreement and pursuant to the registration statement filed with the SEC, but
shall not be removed in any other circumstance without Netergy's prior written
consent (which consent shall not be unreasonably withheld or delayed and shall
be granted if such legend is no longer appropriate).



                                      -16-
<PAGE>   9

        9. ASSIGNMENT OF REGISTRATION RIGHTS. The rights to cause Netergy to
register Registrable Securities and Option Shares pursuant to this Agreement may
not be assigned by the Holders to any person or entity; provided, however, that
upon the death of any Holder, the rights to cause Netergy to register
Registrable Securities and Option Shares pursuant to this Agreement shall inure
to such Holder's heirs, devisees, legatees, legal representatives or other
designees; provided, further, that a Holder may assign the rights to cause
Netergy to register Registrable Securities and the Option Shares pursuant to
this Agreement to a transferee or assignee of Registrable Securities that is (a)
a wholly-owned subsidiary of such Holder, (b) a person who controls such Holder
within the meaning of Section 15 of the Securities Act; (c) a trust for the
benefit of any individual Holder or a member of such Holder's Immediate Family;
or (d) any transferee who becomes the holder of at least twenty five percent
(25%) of the number of the Registrable Securities received by such Holder in
connection with the Share Exchange Agreement and provided, further, that (i) the
transferor shall, within ten (10) days after such transfer, furnish to the
Company written notice of the name and address of such transferee or assignee
and the securities with respect to which such registration rights are being
assigned; and (ii) such transferee or assignee shall agree to be subject to all
restrictions set forth in this Agreement.

        10. AMENDMENT OF REGISTRATION RIGHTS; WAIVERS. This Agreement may be
amended by the Majority Holders and Netergy at any time by execution of an
instrument in writing signed on behalf of each of the parties; provided,
however, that no modification, amendment or waiver that would treat any Holder
of Registrable Securities or Option Shares then outstanding in a non-ratable,
discriminatory manner shall be made without the prior written consent of such
Holder. The failure of any party to enforce any of the provisions of this
Agreement shall in no way be construed as a waiver of such provisions and shall
not affect the right of such party thereafter to enforce each and every
provision of this Agreement in accordance with its terms.

        11. TERMINATION. The registration rights set forth in this Agreement
shall terminate as to any Holder at such time as all of the Registrable
Securities then held by such Holder can be sold by such Holder in a single
3-month period in accordance with the provisions of Rule 144 under the
Securities Act.

        12. GRANT OF ADDITIONAL REGISTRATION RIGHTS. The Holders acknowledge
that Netergy may acquire other companies and in the course of such acquisitions
may grant the equity owners thereof registration rights with respect to their
shares of Netergy on terms which would be negotiated at such time and may be
materially different than the terms of this Agreement.

        13. NOTICES. All notices and other communications required or permitted
hereunder shall be in writing and shall be deemed effectively given upon
delivery to the party to be notified in person or by courier service or five
days after deposit with the United States mail, postage prepaid, addressed (a)
if to the Holders, at the Holders' addresses as set forth in the securities
register of Netergy as the case may be or (b) if to Netergy at 2445 Mission
College Blvd., Santa Clara, California 95054, Attention: President.



                                      -17-
<PAGE>   10

        14. GOVERNING LAW; INTERPRETATION. This Agreement shall be construed in
accordance with and governed for all purposes by the laws of the State of
Delaware regardless of the laws that might otherwise govern under applicable
principles of conflicts of laws thereof.

        15. SEVERABILITY; SURVIVAL. If any portion of this Agreement is held by
a court of competent jurisdiction to conflict with any federal, state or local
law, or to be otherwise invalid or unenforceable, such portion of this Agreement
shall be of no force or effect, and this Agreement shall otherwise remain in
full force and effect and be construed as if such portion had not been included
in this Agreement.

        16. ENTIRE AGREEMENT. This Agreement contains the entire agreement and
understanding of the parties and supersedes all prior discussions, agreements
and understandings relating to the subject matter hereof.

        17. COUNTERPARTS;FACSIMILE SIGNATURES. This Agreement may be executed in
any number of counterparts, all of which shall be considered one and the same
agreement and shall become effective when such counterparts have been signed by
each of the parties and delivered to the other party, it being understood that
all parties need not sign the same counterpart. A facsimile counterpart
signature to this Agreement shall be acceptable if the originally executed
counterpart is delivered within a reasonable period thereafter.

        18. NO CONFLICTS. Netergy represents and warrants to the Holders that
the registration rights granted to the Holders under this Agreement do not
conflict with any other registration rights granted by Netergy. Netergy shall
not, after the date hereof, grant any registration rights which conflict with or
impair the registration rights granted by Netergy hereunder.

        19. SUCCESSORS AND ASSIGNS. This Agreement shall bind and inure to the
benefit of Netergy and the Holders and, subject to Section 9, the respective
successors and assigns of Netergy and the Holders.

        20. HEADINGS. The headings of the various sections of this Agreement
have been inserted for convenience of reference only and shall not be deemed to
be a part of this Agreement.




                            [SIGNATURE PAGE FOLLOWS]



                                      -18-
<PAGE>   11

        IN WITNESS WHEREOF, Netergy and the Holders have caused this Agreement
to be executed as of the date first above written.


                              8X8, INC. (DOING BUSINESS AS NETERGY NETWORKS)

                              By: /s/ Paul Voois
                                  ----------------------------------------------
                                    Paul Voois
                                    Chief Executive Officer


                              SHAREHOLDERS
                              (OTHER THAN 9091-1215 QUEBEC INC.)


                              By: s/ Jean-Luc Calonne
                                  ----------------------------------------------
                                    Jean-Luc Calonne, Shareholder Representative

                              LOGIBRO INC.


                              By: /s/ Michel Poirier
                                  ----------------------------------------------
                                      Michel Poirier
                                      Corporate Representative

                              9091-1215 QUEBEC INC.


                              By:
                                  ----------------------------------------------
                              Name:
                              Title:



                [SIGNATURE PAGE TO REGISTRATION RIGHTS AGREEMENT]



                                      -19-
<PAGE>   12

                                    EXHIBIT A

                                  SHAREHOLDERS


                              9090-1208 Quebec Inc.
                              9090-1109 Quebec Inc.
                              9090-1133 Quebec Inc.
                              9090-1166 Quebec Inc.
                              Michael Cook
                              John Hennessy
                              Jean-Marc Parenteau
                              Jean-Charles Phaneuf
                              Alain Provencher
                              Mario Dorion
                              Martin Leclerc
                              Danny Deschenes
                              Alexandre Garneau
                              Farid Lahdiri
                              Majed Haj Mohamad
                              Marcel St-Amant
                              9091-1215 Quebec Inc.