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                                                                  Exhibit 10.12 


                                                                EXECUTION COPY

                          REGISTRATION RIGHTS AGREEMENT

            This REGISTRATION RIGHTS AGREEMENT is dated as of February 26, 1998
by and among MCMS, Inc., an Idaho corporation and f/k/a Micron Custom
Manufacturing Services, Inc. (the "Company"); Cornerstone Equity Investors IV,
L.P. ("Cornerstone"); MEI California, Inc. ("MEIC"); Randolph Street Partners II
("Randolph"); BT Investment Partners, Inc. ("BT") and the Investors listed on
Appendix A hereto ("the Other Investors").

            As of the date hereof, Cornerstone, MEIC, Randolph, BT and the Other
Investors each own a number of shares of the Company's Common Stock and
Convertible Preferred Stock.

            NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties to this Agreement hereby agree as
follows:

      1. Definitions. As used herein, the following terms shall have the
following meanings.

            "Affiliate" means, when used with reference to a specified Person,
any Person that directly or indirectly controls or is controlled by or is under
common control with the specified Person. As used in this definition, "control"
(including, with its correlative meanings, "controlled by" and "under common
control with") shall mean possession, directly or indirectly, of power to direct
or cause the direction of management or policies (whether through ownership of
securities or partnership or other ownership interests, by contract or
otherwise). With respect to any Person who is an individual, "Affiliates" shall
also include, without limitation, any member of such individual's Family Group.

            "BT Registrable Securities" means (i) all Common Stock acquired by,
or issued or issuable to, BT or any of its Affiliates on or after the date
hereof and (ii) all equity securities issued or issuable directly or indirectly
with respect to any Common Stock described in clause (i) above by way of a stock
dividend or stock split or in connection with a combination of shares,
recapitalization, merger, consolidation or other reorganization. As to any
particular BT Registrable Securities, such securities shall cease to be BT
Registrable Securities when they have been distributed to the public pursuant to
an offering registered under the Securities Act or sold to the public in
compliance with Rule 144. For purposes of this Agreement, a Person will be
deemed to be a holder of BT Registrable Securities whenever such Person has the
right to acquire directly or indirectly such BT Registrable Securities (upon
conversion or exercise in connection with a transfer of securities or otherwise,
but disregarding any restrictions or limitations upon the exercise of such
right), whether or not such acquisition has actually been effected.

            "Class A Common" means the Company's Class A Common Stock, par value
$.001 per share.

            "Class B Common" means the Company's Class B Common Stock, par value
$.001 per share.
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            "Class C Common" means the Company's Class C Common Stock, par value
$.001 per share.

            "Common Stock" means, collectively, Class A Common, Class B Common,
Class C Common and any other common stock authorized by the Company.

            "Cornerstone Investors" means Cornerstone and Randolph.

            "Cornerstone Investors Registrable Securities" means (i) all Common
Stock acquired by, or issued or issuable to, any of the Cornerstone Investors or
any of their respective Affiliates on or after the date hereof and (ii) all
equity securities issued or issuable directly or indirectly with respect to any
Common Stock described in clause (i) above by way of a stock dividend or stock
split or in connection with a combination of shares, recapitalization, merger,
consolidation or other reorganization. As to any particular Cornerstone
Investors Registrable Securities, such securities shall cease to be Cornerstone
Investors Registrable Securities when they have been distributed to the public
pursuant to an offering registered under the Securities Act or sold to the
public in compliance with Rule 144. For purposes of this Agreement, a Person
will be deemed to be a holder of Cornerstone Investors Registrable Securities
whenever such Person has the right to acquire directly or indirectly such
Cornerstone Investors Registrable Securities (upon conversion or exercise in
connection with a transfer of securities or otherwise, but disregarding any
restrictions or limitations upon the exercise of such right), whether or not
such acquisition has actually been effected.

            "Exchange Act" means the Securities Exchange Act of 1934, as
amended, and the rules and regulations of the SEC promulgated thereunder.

            "Family Group" means, with respect to any Person who is an
individual, (i) such Person's spouse, former spouse and descendants (whether
natural or adopted), parents and their descendants and any spouse of the
foregoing persons (collectively, "relatives") or (ii) the trustee, fiduciary or
personal representative of such Person and any trust solely for the benefit of
such Person and/or such Person's relatives.

            "MEIC Registrable Securities" means (i) all Common Stock acquired
by, or issued or issuable to, MEIC or any of its Affiliates on or after the date
hereof and (ii) all equity securities issued or issuable directly or indirectly
with respect to any Common Stock described in clause (i) above by way of a stock
dividend or stock split or in connection with a combination of shares,
recapitalization, merger, consolidation or other reorganization. As to any
particular MEIC Registrable Securities, such securities shall cease to be MEIC
Registrable Securities when they have been distributed to the public pursuant to
an offering registered under the Securities Act or sold to the public in
compliance with Rule 144. For purposes of this Agreement, a Person will be
deemed to be a holder of MEIC Registrable Securities whenever such Person has
the right to acquire directly or indirectly such MEIC Registrable Securities
(upon conversion or exercise in connection with a transfer of securities or
otherwise, but disregarding any restrictions or limitations upon the exercise of
such right), whether or not such acquisition has actually been effected.

            "Other Investors Registrable Securities" means (i) all Common Stock
acquired by, or issued or issuable to, any of the Other Investors or any of
their respective Affiliates on or after


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the date hereof and (ii) all equity securities issued or issuable directly or
indirectly with respect to any Common Stock described in clause (i) above by way
of a stock dividend or stock split or in connection with a combination of
shares, recapitalization, merger, consolidation or other reorganization. As to
any particular Other Investors Registrable Securities, such securities shall
cease to be Other Investors Registrable Securities when they have been
distributed to the public pursuant to an offering registered under the
Securities Act or sold to the public in compliance with Rule 144. For purposes
of this Agreement, a Person will be deemed to be a holder of Other Investors
Registrable Securities whenever such Person has the right to acquire directly or
indirectly such Other Investors Registrable Securities (upon conversion or
exercise in connection with a transfer of securities or otherwise, but
disregarding any restrictions or limitations upon the exercise of such right),
whether or not such acquisition has actually been effected.

            "Person" means an individual, a partnership, a corporation, a
limited liability company, an association, a joint stock company, a trust, a
joint venture, an unincorporated organization, a bank, a trust company, a land
trust, a business trust, a governmental entity or any department, agency or
political subdivision thereof or any other entity or organization, whether or
not it is a legal entity.

            "Public Offering" means an underwritten public offering and sale of
the Common Stock pursuant to an effective registration statement under the
Securities Act; provided that a Public Offering shall not include an offering
made in connection with a business acquisition or combination pursuant to a
registration statement on Form S-4 or any similar form, or an employee benefit
plan pursuant to a registration statement on Form S-8 or any similar form.

            "Registrable Securities" means, collectively, the Cornerstone
Investors Registrable Securities, the MEIC Registrable Securities, the BT
Registrable Securities and the Other Investors Registrable Securities.

            "Registration Expenses" means all expenses incident to the Company's
performance of or compliance with this Agreement, including without limitation
all registration and filing fees, fees and expenses of compliance with
securities or blue sky laws, printing and distributing expenses, messenger and
delivery expenses, fees and expenses of custodians, internal expenses (including
all salaries and expenses of its officers and employees performing legal or
accounting duties), the expense of any annual audit or quarterly review, the
expense of any liability insurance and the expenses and fees for listing the
securities to be registered on each securities exchange on which similar
securities issued by the Company are then listed or on the NASD automated
quotation system, and fees and disbursements of counsel for the Company and all
independent certified public accountants, underwriters (excluding discounts and
commissions) and other Persons retained by the Company.

            "Rule 144" means Rule 144 under the Securities Act (or any similar
rule then in force).

            "SEC" means the Securities and Exchange Commission.

            "Securities Act" means the Securities Act of 1933, as amended.


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            "Subsidiary" means, with respect to any Person, any corporation,
partnership, limited liability company, association or other business entity of
which (i) if a corporation, a majority of the total voting power of shares of
stock entitled (without regard to the occurrence of any contingency) to vote in
the election of directors thereof is at the time owned or controlled, directly
or indirectly, by that Person or one or more of the other Subsidiaries of that
Person or a combination thereof, or (ii) if a partnership, limited liability
company, association or other business entity, a majority of the partnership or
other similar ownership interest thereof is at the time owned or controlled,
directly or indirectly, by that Person or one or more Subsidiaries of that
Person or a combination thereof. For purposes hereof, a Person or Persons shall
be deemed to have a majority ownership interest in a partnership, limited
liability company, association or other business entity if such Person or
Persons shall be allocated a majority of partnership, limited liability company,
association or other business entity gains or losses or shall be or control the
managing director, managing member, manager or a general partner of such
partnership, limited liability company, association or other business entity.

      2. Demand Registrations.

            (a) Requests for Registration. At any time after the date hereof,
the holder(s) of a majority of the Cornerstone Investors Registrable Securities
may request registration under the Securities Act of all or any portion of their
Registrable Securities on Form S-1 or any similar long-form registration (a
"Long-Form Registration"), or on Form S-2 or S-3 or any similar short-form
registration (a "Short-Form Registration") if such a short form is available. At
any time after the date two years after the consummation of an initial Public
Offering, if BT and its Affiliates (and not any of their respective assigns) own
greater than 5% of the then outstanding shares of Common Stock (on a fully
diluted basis), then BT and/or its Affiliates (and not any of their respective
assigns) may request registration under the Securities Act of all or any portion
of its or their Registrable Securities on Form S-1 or any similar long-form
registration (also, a "Long-Form Registration"), or on Form S-2 or S-3 or any
similar short-form registration (also, a "Short-Form Registration") if such
short form is available. All registrations requested pursuant to this Section
2(a) are referred to herein as "Demand Registrations". Each request for a Demand
Registration (a "Demand Request") shall specify the approximate number of
Registrable Securities requested to be registered, the anticipated method or
methods of distribution and the anticipated per share price range for such
offering. Within ten days after receipt of any such Demand Request, the Company
will give written notice of such requested registration (which shall specify the
intended method of disposition of such Registrable Securities) to all other
holders of Registrable Securities (a "Company Notice") and the Company will
include (subject to the provisions of this Agreement) in such registration, all
Registrable Securities with respect to which the Company has received written
requests for inclusion therein within 20 days after the delivery of such Company
Notice; provided that any such other holder may withdraw its request for
inclusion at any time prior to executing the underwriting agreement or, if none,
prior to the applicable registration statement becoming effective.

            (b) Long-Form Registrations.

                  (i) The holders of Cornerstone Investors Registrable
Securities will be entitled to three Long-Form Registrations. A registration
will not count as one of the permitted Long-Form Registrations for purposes of
the preceding sentence unless and until it has become effective and no Long-Form
Registration will count as a Long-Form Registration for purposes of


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the preceding sentence unless the applicable holders of Cornerstone Investors
Registrable Securities sell at least 75% of the Registrable Securities requested
to be included by them in such registration.

                  (ii) Subject to the conditions contained in Section 2(a), BT
and its Affiliates (and not any of their respective assigns) will be entitled to
two Long-Form Registration which shall include the registration of Registrable
Securities which yield at least $5,000,000 of net proceeds to the sellers of
such Registrable Securities. A registration will not count as one of the
permitted Long-Form Registrations for purposes of the preceding sentence unless
and until it has become effective and no Long-Form Registration will count as a
Long-Form Registration for purposes of the preceding sentence unless BT and its
Affiliates (and not any of their respective assigns) are able to register and
sell at least 75% of the Registrable Securities requested to be included by them
in such registration.

                  (iii) The Company will pay all Registration Expenses in
connection with any registration initiated as a Long-Form Registration whether
or not it has become effective.

            (c) Short-Form Registrations.

                  (i) The holders of Cornerstone Investors Registrable
Securities will be entitled to unlimited Short-Form Registrations. Demand
Registrations by holders of Cornerstone Investors Registrable Securities will be
Short-Form Registrations whenever the Company is permitted to use any applicable
short form. After the Company has become subject to the reporting requirements
of the Exchange Act, the Company will use its best efforts to make Short-Form
Registrations on Form S-3 available for the sale of Cornerstone Investors
Registrable Securities.

                  (ii) Subject to the conditions contained in Section 2(a), BT
and its Affiliates (and not any of their respective assigns) will be entitled to
three Short-Form Registration which shall include the registration of
Registrable Securities which yield at least $5,000,000 of net proceeds to the
sellers of such Registrable Securities. A registration will not count as one of
the permitted Short-Form Registrations for purposes of the preceding sentence
unless and until it has become effective and no Short-Form Registration will
count as a Short-Form Registration for purposes of the preceding sentence unless
BT and its Affiliates (and not any of their respective assigns) are able to
register and sell at least 75% of the Registrable Securities requested to be
included by them in such registration.

                  (iii) The Company will pay all Registration Expenses in
connection with any registration initiated as a Short-Form Registration whether
or not it has become effective.

            (d) Priority on Demand Registrations.

                  (i) The Company will not include in any Demand Registration
any securities which are not Registrable Securities unless holder(s) of a
majority of the Registrable Securities initiating such Demand Registration
pursuant to Section 2(a) otherwise consent.

                  (ii) If a Demand Registration is an underwritten offering and
the managing underwriters advise the Company in writing that in their opinion
the number of Registrable Securities and, if permitted hereunder, other
securities, requested to be included in such offering


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exceeds the number of Registrable Securities and other securities, if any, which
can be sold in an orderly manner in such offering within a price range
acceptable to holder(s) of a majority of the Registrable Securities initiating
such Demand Registration pursuant to Section 2(a) and without adversely
affecting the marketability of the offering, then the Company will include in
such Demand Registration (A) first, the number of Registrable Securities
requested to be included in such Demand Registration, pro rata from among the
holders of such Registrable Securities according to the number of Registrable
Securities requested by them to be so included, and (B) second, any other
securities of the Company requested to be included in such registration, in such
manner as the Company may determine.

            (e) Restrictions on Demand Registrations.

                  (i) The Company will not be obligated to file any registration
statement with respect to any Long-Form Registration within 180 days after the
effective date of a previous Long-Form Registration or a previous registration
in which the holders of Registrable Securities were given piggyback rights
pursuant to Section 3 and in which there were included not less than 80% of the
number of Registrable Securities requested to be included.

                  (ii) The Company may postpone for up to 90 days the filing or
the effectiveness of a registration statement for a Demand Registration if the
Company determines that such Demand Registration would reasonably be expected to
have a material adverse effect on any proposal or plan by the Company or any of
its Subsidiaries to engage in any acquisition of assets (other than in the
ordinary course of business) or any merger, consolidation, tender offer,
reorganization or similar transaction; provided that in such event the holders
of Registrable Securities initiating such Demand Registration pursuant to
Section 2(a) will be entitled to withdraw such request and, if such request is
withdrawn, such Demand Registration will not count as one of the permitted
Demand Registrations hereunder and the Company will pay all Registration
Expenses in connection with such requested registration. The Company may use the
provisions of this clause (ii) to delay a Demand Registration initiated by
holders of Cornerstone Investors Registrable Securities only once during any
twelve-month period. The Company may use the provisions of this clause (ii) to
delay a Demand Registration initiated by BT and/or any of its Affiliates only
once during any twelve-month period.

            (f) Selection of Underwriters. In the case of a Demand Registration
for an underwritten offering initiated by holders of Cornerstone Investors
Registrable Securities, the holders of a majority of the Cornerstone Investors
Registrable Securities to be included in such Demand Registration will have the
right to select the investment banker(s) and manager(s) to administer the
offering (which investment banker(s) and manager(s) will be nationally
recognized) subject to the Company's approval, which will not be unreasonably
withheld. In the case of any other Demand Registration for an underwritten
offering, the Company will have the right to select the investment banker(s) and
manager(s) to administer the offering (which investment banker(s) and manager(s)
will be nationally recognized).

            (g) Other Registration Rights. Except as provided in this Agreement,
after the date hereof, the Company (i) will not grant to any Persons the right
to request the Company to register any equity or similar securities of the
Company, or any securities convertible or exchangeable into or exercisable for
such securities, without the prior written consent of the holders


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of a majority of the Cornerstone Investors Registrable Securities and (ii) will
not grant to any Persons any such rights to the extent such rights conflict
with, or are adverse to, the rights of the holders of Registrable Securities
without the consent of holders of at least two-thirds of the Registrable
Securities (other than the Cornerstone Investors Registrable Securities) and a
majority of the holders of the Cornerstone Investors Registrable Securities.

      3. Piggyback Registrations.

            (a) Right to Piggyback. Whenever the Company proposes to register
any of its Common Stock under the Securities Act for its own account or for the
account of any holder of Common Stock (other than pursuant to a Demand
Registration, and other than pursuant to a registration statement on Form S-8 or
S-4 or any similar or successor form) (a "Piggyback Registration"), the Company
will give prompt written notice to all holders of Registrable Securities of its
intention to effect such a registration and of such holders' rights under this
Section 3(a). Upon the written request of any holder of Registrable Securities
(which request shall specify the Registrable Securities intended to be disposed
of by such holder and the intended method of disposition thereof), the Company
shall include in such registration (subject to the provisions of this Agreement)
all Registrable Securities requested to be registered pursuant to this Section
3(a), subject to Section 3(b) below, with respect to which the Company has
received written requests for inclusion therein within 20 days after the receipt
of the Company's notice; provided that any such other holder may withdraw its
request for inclusion at any time prior to executing the underwriting agreement
or, if none, prior to the applicable registration statement becoming effective.

            (b) Priority on Primary Registrations. If a Piggyback Registration
is in part 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 and without adversely affecting the
marketability of the offering, then the Company will include in such
registration (i) first, the securities the Company proposes to sell, (ii)
second, the Registrable Securities requested to be included in such
registration, pro rata from among the holders of such Registrable Securities
according to the number of Registrable Securities requested by them to be so
included, and (iii) third, any other securities requested to be included in such
registration, in such manner as the Company may determine.

            (c) Priority on Secondary Registrations. If a Piggyback Registration
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 and without adversely affecting the marketability of the
offering, then the Company will include in such registration (i) first, the
securities requested to be included therein by the holders requesting such
registration and the Registrable Securities requested to be included in such
registration, pro rata from among such holders and the holders of such
Registrable Securities according to the number of Registrable Securities
requested by them to be so included, and (ii) second, any other securities
requested to be included in such registration, in such manner as the Company may
determine.


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            (d) Other Registrations. If the Company has previously filed a
registration statement with respect to Registrable Securities pursuant to
Section 2 or pursuant to this Section 3, and if such previous registration has
not been withdrawn or abandoned, then all the parties hereto agree that the
Company shall not be required to effect any other registration of any of its
equity or similar securities or securities convertible or exchangeable into or
exercisable for its equity or similar securities under the Securities Act
(except on Forms S-4 or S-8 or any successor or similar form or in connection
with a Demand Registration), whether on its own behalf or at the request of any
holder or holders of such securities, until a period of at least 180 days has
elapsed from the effective date of such previous registration.

            (e) Registration Expenses. The Company will pay all Registration
Expenses in connection with any Piggyback Registration whether or not such
Piggyback Registration has become effective.

      4. Holdback Agreements.

            (a) Each holder of Registrable Securities hereby agrees not to
effect any sale or distribution of equity securities of the Company, or any
securities convertible into or exchangeable or exercisable for such securities,
during the seven days prior to and the 180-day period beginning on the effective
date of any underwritten Demand Registration or any underwritten Piggyback
Registration (except as part of such underwritten registration), unless the
underwriters managing such underwritten registration otherwise agree (which
agreement shall be equally applicable to all holders of Registrable Securities).

            (b) The Company (i) will not effect any sale or distribution of its
equity securities, or any securities convertible into or exchangeable or
exercisable for such securities, during the seven days prior to and during the
180-day period beginning on the effective date of any underwritten Demand
Registration or any underwritten Piggyback Registration (except as part of such
underwritten registration or pursuant to registrations on Forms S-4 or S-8 or
any successor or similar form), unless the underwriters managing such
underwritten registration otherwise agree (which agreement shall be equally
applicable to all holders of Registrable Securities), and (ii) will cause each
holder of at least 2% (on a fully diluted basis) of Common Stock and all members
of its management holding Common Stock, or any securities convertible into or
exchangeable or exercisable for Common Stock, purchased from the Company at any
time after the date of this Agreement (other than in a registered public
offering) to agree not to effect any sale or distribution of any such securities
during such period (except as part of such underwritten registration, if
otherwise permitted), unless the underwriters managing such underwritten
registration otherwise agree.

      5. Registration Procedures. Whenever the holders of Registrable Securities
have requested that any Registrable Securities be registered pursuant to this
Agreement, the Company will use its best efforts to effect the registration and
the sale of such Registrable Securities in accordance with the intended method
of disposition thereof, and pursuant thereto the Company will as expeditiously
as possible:

            (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


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effective (provided that before filing a registration statement or prospectus or
any amendments or supplements thereto, the Company will furnish to the counsel
selected pursuant to Section 6(b) below copies of all such documents proposed to
be filed, which documents will be subject to the prompt review and reasonable
comment of such counsel), and upon filing such documents, the Company shall
promptly notify in writing such counsel of the receipt by the Company of any
written comments by the SEC with respect to such registration statement or
prospectus or any amendment or supplement thereto or any written request by the
SEC for the amending or supplementing thereof or for additional information with
respect thereto;

            (b) prepare and file with the SEC 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 for a period of
not less than 180 days and comply with the provisions of the Securities Act with
respect to the disposition of all Registrable Securities covered by such
registration statement during such period in accordance with the intended
methods of disposition by the sellers thereof set forth in such registration
statement and cause the prospectus to be supplemented by any required prospectus
supplement, and as so supplemented to be filed pursuant to Rule 424 under the
Securities Act;

            (c) furnish to each seller of Registrable Securities such number of
copies of such registration statement, each amendment and supplement thereto,
the prospectus included in such registration statement (including each
preliminary prospectus) and such other documents as such seller may reasonably
request in order to facilitate the disposition of the Registrable Securities
owned by such seller;

            (d) use its best efforts to register or qualify such Registrable
Securities under such other securities or blue sky laws of such jurisdictions as
any seller reasonably requests and do any and all other acts and things which
may be reasonably necessary or advisable to enable such seller to consummate the
disposition in such jurisdictions of the Registrable Securities owned by such
seller (provided that the Company will not be required to (i) qualify generally
to do business in any jurisdiction where it would not otherwise be required to
qualify but for this subsection, (ii) subject itself to taxation in any such
jurisdiction in any jurisdiction where it is not so subject or (iii) consent to
general service of process (i.e., service of process which is not limited solely
to securities law violations) in any such jurisdiction in any jurisdiction where
it is not so subject);

            (e) promptly notify each seller of such Registrable Securities, at
any time when a prospectus relating thereto is required to be delivered under
the Securities Act, upon discovery that, or upon the discovery of the happening
of any event as a result of which the prospectus included in such registration
statement contains an untrue statement of a material fact or omits any fact
necessary to make the statements therein not misleading in light of the
circumstances under which they were made, and, at the request of any such
seller, the Company will, as soon as reasonably practicable, file and furnish to
all sellers a supplement or amendment to such prospectus so that, as thereafter
delivered to the purchasers of such Registrable Securities, such prospectus will
not contain an untrue statement of a material fact or omit to state any fact
necessary to make the statements therein not misleading in light of the
circumstances under which they were made;

            (f) cause all such Registrable Securities to be listed on each
securities exchange on which similar securities issued by the Company are then
listed and, if not so listed, to be listed


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on the Nasdaq National Market System ("Nasdaq Market") and, if listed on the
Nasdaq Market, use its best efforts to secure designation of all such
Registrable Securities covered by such registration statement as a Nasdaq
"National Market System security" within the meaning of Rule 11Aa2-1 under the
Exchange Act or, failing that, to secure Nasdaq Market authorization for such
Registrable Securities and, without limiting the generality of the foregoing, to
arrange for at least two market makers to register as such with respect to such
Registrable Securities with the National Association of Securities Dealers;

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

            (h) enter into such customary agreements (including underwriting
agreements in customary form) and take all such other actions as the holders of
a majority of the Registrable Securities being sold or the underwriters, if any,
reasonably request in order to expedite or facilitate the disposition of such
Registrable Securities (including, without limitation, effecting a split or a
combination of stock or units); provided that no holder of Registrable
Securities shall have any indemnification or contribution obligations
inconsistent with Section 7 hereof;

            (i) make available for inspection by any seller of Registrable
Securities, any underwriter participating in any disposition pursuant to such
registration statement and any attorney, accountant or other agent retained by
any such seller or underwriter, all financial and other records, pertinent
corporate documents and properties of the Company, and cause the Company's
officers, directors, employees and independent accountants to supply all
information and participate in due diligence sessions reasonably requested by
any such seller, underwriter, attorney, accountant or agent in connection with
such registration statement;

            (j) otherwise use its best efforts to comply with all applicable
rules and regulations of the SEC, and make available to its security holders, as
soon as reasonably practicable, an earnings statement covering the period of at
least twelve months beginning with the first day of the Company's first full
calendar quarter after the effective date of the registration statement, which
earnings statement shall satisfy the provisions of Section 11(a) of the
Securities Act and Rule 158 promulgated thereunder;

            (k) use reasonable best efforts to prevent the issuance of any stop
order ("Stop Order") suspending the effectiveness of a registration statement,
or of any order suspending or preventing the use of any related prospectus or
suspending the qualification of any securities included in such registration
statement for sale in any jurisdiction, and, in the event of such issuance, the
Company shall immediately notify the holders of Registrable Securities included
in such registration statement of the receipt by the Company of such
notification and shall use its best efforts promptly to obtain the withdrawal of
such order;

            (l) use its best efforts to cause such Registrable Securities
covered by such registration statement to be registered with or approved by such
other governmental agencies or authorities as may be necessary to enable the
sellers thereof to consummate the disposition of such Registrable Securities,
and cooperate and assist with any filings to be made with the NASD;


                                    - 10 -
   11

            (m) obtain one or more "cold comfort" letters, dated the effective
date of such registration statement (and, if such registration includes an
underwritten public offering, dated the date of the closing under the
underwriting agreement), signed by the Company's independent public accountants
in customary form and covering such matters of the type customarily covered by
"cold comfort" letters as the holders of a majority of the Registrable
Securities being sold reasonably request;

            (n) provide a legal opinion of the Company's outside counsel, dated
the effective date of such registration statement (and, if such registration
includes an underwritten public offering, dated the date of the closing under
the underwriting agreement), with respect to the registration statement, each
amendment and supplement thereto, the prospectus included therein (including the
preliminary prospectus) and such other documents relating thereto in customary
form and covering such matters of the type customarily covered by legal opinions
of such nature; and

            (o) use its best efforts to cause its officers to support the
marketing of the Registrable Securities being sold (including, without
limitation, their participation in "road shows" as may be reasonably requested
by the underwriters administering the offering and sale of such Registrable
Securities) to the extent reasonably possible taking into account such officers'
responsibilities to manage the Company's business.

If any such registration or comparable statement refers to any holder by name or
otherwise as the holder of any securities of the Company and if in such holder's
sole and exclusive judgment, such holder is or might be deemed to be an
underwriter or a controlling person of the Company, such holder shall have the
right to require (i) the insertion therein of language, in form and substance
satisfactory to such holder and presented to the Company in writing, to the
effect that the holding by such holder of such securities is not to be construed
as a recommendation by such holder of the investment quality of the Company's
securities covered thereby and that such holding does not imply that such holder
will assist in meeting any future financial requirements of the Company, or (ii)
in the event that such reference to such holder by name or otherwise is not
required by the Securities Act or any similar Federal statute then in force, the
deletion of the reference to such holder; provided, that with respect to this
clause (ii), if requested by the Company, such holder shall furnish to the
Company an opinion of counsel to such effect, which opinion and counsel shall be
reasonably satisfactory to the Company.

      6. Registration Expenses.

            (a) All expenses incident to the Company's performance of or
compliance with this Agreement, including without limitation all Registration
Expenses, will be borne by the Company.

            (b) In connection with each Demand Registration and each Piggyback
Registration, the Company will reimburse the holders of Registrable Securities
included in such registration for the reasonable fees and disbursements of one
counsel chosen by the holders of a majority of the Registrable Securities
initially requesting such registration (which counsel shall be retained to
represent all such holders).


                                    - 11 -
   12

      7. Indemnification.

            (a) By the Company. The Company agrees to, and will cause each of
its Subsidiaries to agree to, indemnify, to the fullest extent permitted by law,
each holder of Registrable Securities, its officers, directors, members,
employees, agents, stockholders and general and limited partners and each Person
who controls such holder (within the meaning of the Securities Act and Exchange
Act) against any and all losses, claims, damages, liabilities and expenses (or
actions or proceedings, whether commenced or threatened, in respect thereof),
joint or several, arising out of or based upon any untrue or alleged untrue
statement of material fact contained in any registration statement, reports
required and other documents filed under the Exchange Act, prospectus or
preliminary prospectus or any amendment thereof or supplement thereto, together
with any documents incorporated therein by reference, or any omission or alleged
omission of a material fact required to be stated therein or necessary to make
the statements therein not misleading, or any violation or alleged violation by
the Company or any of its Subsidiaries of any federal, state, foreign or common
law rule or regulation and relating to action or inaction in connection with any
such registration, disclosure document or other document and shall reimburse
such holder, officer, director, member, employee, agent, stockholder, partner or
controlling Person for any legal or other expenses, including any amounts paid
in any settlement effected with the consent of the Company, which consent will
not be unreasonably withheld or delayed, incurred by such holder, officer,
director, member, employee, agent, stockholder, partner or controlling Person in
connection with the investigation or defense of such loss, claim, damage,
liability or expense, except insofar as the same are caused by or contained in
any information furnished in writing to the Company by such holder expressly for
use therein. In connection with an underwritten offering, the Company will
indemnify such underwriters, their officers, directors, agents and employees and
each Person who controls such underwriters (within the meaning of the Securities
Act) to the same extent as provided above with respect to the indemnification of
the holders of Registrable Securities.

            (b) By the Holders. In connection with any registration statement in
which a holder of Registrable Securities is participating, each such holder will
furnish to the Company in writing such information and affidavits about such
holder as the Company reasonably requests for use in connection with any such
registration statement or prospectus and, to the extent permitted by law, will
indemnify the Company, its directors and officers and each Person who controls
the Company (within the meaning of the Securities Act) and the other holders of
Registrable Securities against any losses, claims, damages, liabilities and
expenses resulting from any untrue or alleged untrue statement of material fact
contained in the registration statement, prospectus or preliminary prospectus or
any amendment thereof or supplement thereto or any omission or alleged omission
of 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 omission is contained in any information or affidavit so furnished
in writing by such holder which authorizes its use in the applicable document;
provided, that the obligation to indemnify will be individual, not joint and
several, for each holder and will be limited to the net amount of proceeds
received by such holder from the sale of Registrable Securities pursuant to such
registration statement.

            (c) Claim Procedures. Any Person entitled to indemnification
hereunder will (i) give prompt written notice to the indemnifying party of any
claim with respect to which it seeks indemnification (provided that the failure
to give prompt notice will not impair any Person's right to indemnification
hereunder to the extent such failure has not prejudiced the indemnifying party)


                                    - 12 -
   13

and (ii) unless in such indemnified party's reasonable judgment a conflict of
interest between such indemnified and indemnifying parties may exist with
respect to such claim, permit the indemnifying party to assume the defense
thereof, jointly with any other indemnifying party similarly notified to the
extent it may wish, with counsel reasonably satisfactory to the indemnified
party. If such defense is assumed, the indemnifying party will not be subject to
any liability for any settlement made by the indemnified party without its
consent (but such consent will not be unreasonably withheld or delayed) and the
indemnifying party shall not, without the consent of the indemnified party,
consent to entry of any judgment or enter into any settlement which does not
include as an unconditional term thereof, a release from all liability in
respect of such claim or litigation provided by the claimant or plaintiff to
such indemnified party. An indemnifying party who is not entitled to, or elects
not to, assume the defense of a claim will not be obligated to pay (i) the fees
and expenses of more than one counsel for all parties indemnified by such
indemnifying party with respect to such claim, unless in the reasonable judgment
of any indemnified party a conflict of interest may exist between such
indemnified party and any other of such indemnified parties with respect to such
claim or (ii) any settlement made by any indemnified party without such
indemnifying party's consent (but such consent will not be unreasonably
withheld).

            (d) Survival; Contribution. The indemnification provided for under
this Agreement will remain in full force and effect regardless of any
investigation made by or on behalf of the indemnified party or any officer,
agent or employee and each other Person who participates as an underwriter in
the offering or sale of such securities and each other Person, if any, who
controls such indemnified party (within the meaning of the Securities Act), and
will survive the transfer of securities. The Company also agrees to make such
provisions, as are reasonably requested by any indemnified party, for
contribution to such party in the event the Company's indemnification is
unavailable for any reason.

      8. Participation in Underwritten Registrations. No Person may participate
in any registration hereunder which is underwritten unless such Person (a)
agrees to sell such Person's securities on the basis provided in any
underwriting arrangements approved by the Person or Persons entitled hereunder
to approve such arrangements (including, without limitation, pursuant to the
terms of any over-allotment or "green shoe" option requested by the managing
underwriter(s), provided that no holder of Registrable Securities will be
required to sell more than the number of Registrable Securities that such holder
has requested the Company to include in any registration) and (b) completes and
executes all customary questionnaires, powers of attorney, indemnities,
underwriting agreements and other documents required under the terms of such
underwriting arrangements; provided, that no holder of Registrable Securities
included in any underwritten registration shall be required to make any
representations or warranties to the Company or the underwriters (other than
representations and warranties regarding such holder and such holder's intended
method of distribution) or to undertake any indemnification or contribution
obligations to the Company or the underwriters with respect thereto, except as
otherwise provided in Section 7.


                                    - 13 -
   14

      9. Rule 144 Reporting. With a view to making available to the holders of
Registrable Securities 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 its expense to use its best efforts to:

            (a) make and keep current public information available, within the
meaning of Rule 144 or any similar or analogous rule promulgated under the
Securities Act, at all times after it has become subject to the reporting
requirements of the Exchange Act;

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

            (c) so long as any party hereto owns any Registrable Securities,
furnish to such Person forthwith upon request, a written statement by the
Company as to its compliance with the reporting requirements of said Rule 144
(at any time commencing 90 days after the effective date of the first
registration filed by the Company for an offering of its securities to the
general public), 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
as such Person may reasonably request in availing itself of any rule or
regulation of the SEC allowing it to sell any such securities without
registration.

      10. Notices. All notices, demands or other communications to be given or
delivered under or by reason of the provisions of this Agreement will be in
writing and will be deemed to have been given when delivered if delivered
personally, sent via a nationally recognized overnight courier, or sent via
facsimile to the recipient, or if sent by certified or registered mail, return
receipt requested, will be deemed to have been given two business days
thereafter. Such notices, demands and other communications will be sent to the
address indicated below:

            To the Company:

                  MCMS, Inc.
                  16399 Franklin Road
                  Nampa, Idaho  83687
                  Attention:  President
                  Telecopy No.:  (208) 893-8711


                                    - 14 -
   15

            With a copy, which shall not constitute notice, to:

                  Cornerstone Equity Investors, LLC
                  717 Fifth Avenue, Suite 1100
                  New York, NY  10022
                  Attention:  Tony Downer
                              Michael E. Najjar
                  Telecopy No.:  (212) 826-6798

                  Kirkland & Ellis
                  Citicorp Center
                  153 East 53rd Street
                  New York, New York  10022
                  Attention: Frederick Tanne, Esq.
                  Telecopy No.:  (212) 446-4900

            To any Cornerstone Investor:

                  Cornerstone Equity Investors, LLC
                  717 Fifth Avenue, Suite 1100
                  New York, NY  10022
                  Attention:  Tony Downer
                              Michael E. Najjar
                  Telecopy No.:  (212) 826-6798
            
            With a copy, which shall not constitute notice, to:
            
                  Kirkland & Ellis
                  Citicorp Center
                  153 East 53rd Street
                  New York, New York  10022
                  Attention: Frederick Tanne, Esq.
                  Telecopy No.:  (212) 446-4900

            To Randolph:
            
                  Kirkland & Ellis
                  Citicorp Center
                  153 East 53rd Street
                  New York, New York  10022
                  Attention: Frederick Tanne, Esq.
                  Telecopy No.:  (212) 446-4900
            

                                     - 15 -
   16
            
            To MEIC:
            
                  MEI California, Inc.
                  c/o Micron Electronics, Inc.
                  900 East Karcher Road
                  Nampa, Idaho  83687
                  Attention:  General Counsel
                  Telecopy No.:  (208) 898-7411
            
            With a copy, which shall not constitute notice, to:
            
                  Wachtell, Lipton, Rosen & Katz
                  51 West 52nd Street
                  New York, New York  10019
                  Attention:  Barry A. Bryer
                  Telecopy No.:  (212) 403-2000
            
            To BT:
            
                  BT Investment Partners, Inc.
                  130 Liberty Street
                  New York, New York  10006
                  Attention:  Joseph Wood
                  Telecopy No.:  (212) 250-8375
            
            With a copy, which shall not constitute notice, to:
            
                  White & Case LLP
                  1155 Avenue of the Americas
                  New York, New York  10036
                  Attention:  John M. Reiss, Esq.
                  Telecopy No.:  (212) 354-8113
            
            To Chris Anton:
            
                  c/o  MCMS, Inc.
                  16399 Franklin Road
                  Nampa, Idaho 83687
                  Telecopy No.:  (208) 898-2796
            
            To Jess Asla:
            
                  c/o  MCMS, Inc.
                  16399 Franklin Road
                  Nampa, Idaho 83687
                  Telecopy No.:  (208) 898-2796
            

                                          - 16 -
   17
            
            To John McCarvel:
            
                  c/o  MCMS, Inc.
                  16399 Franklin Road
                  Nampa, Idaho 83687
                  Telecopy No.:  (208) 898-2796

            To Robert F. Subia:
            
                  c/o  MCMS, Inc.
                  16399 Franklin Road
                  Nampa, Idaho 83687
                  Telecopy No.:  (208) 898-2796
            
            To R. Stephen Cheheyl:
            
                  130 Lane's End
                  Concord, Massachussets 01742
                  Telecopy No.: (978) 369-4607
            
            To Finis Connor:
            
                  The Connor Group
                  San Carlos and Fourth Street
                  Unit No. 2
                  Carmel, CA  93921
                  Telecopy No.:  (408) 625-8613
            
            To Nicholas Keating:
            
                  2477 Jackson Street
                  San Francisco, CA  94115
                  Telephone No.:  (650) 771-2989
            
            To Oak Investment Partners VII, Limited Partnership:
            
                  Oak Investment Partners
                  525 University Avenue, Suite 1300
                  Palo Alto, CA  94301
                  Attention:  Fredric W. Harman
                  Telecopy No.:  (650) 328-6345
            

                                     - 17 -
   18
            
            To Oak VII Affiliate Fund, Limited Partnership:
            
                  Oak Investment Partners
                  525 University Avenue, Suite 1300
                  Palo Alto, CA  94301
                  Attention:  FredricW. Harman
                  Telecopy No.:  (650) 328-6345
            
            To Norman Nie:
            
                  c/o  Oak Investment Partners
                  525 University Avenue, Suite 1300
                  Palo Alto, CA  94301
                  Attention:  FredricW. Harman
                  Telecopy No.:  (650) 328-6345
            
            To August Capital, L.P. for itself and as nominee for August Capital
            Strategic Partners, L.P. and August Capital Associates, L.P.:
            
                  August Capital Management, L.L.C.
                  2480 Sandy Hill, Suite 101
                  Menlo Park, CA 94025
                  Attention:  Mark G. Wilson
                  Telecopy No.:  (650) 234-9910
            
            or such other address or to the attention of such other person as
            the recipient party shall have specified by prior written notice to
            the sending party.
            
      11. Miscellaneous.

            (a) No Inconsistent Agreements. The Company represents and warrants
to the holders of Registrable Securities that the registration rights granted to
the holders of such securities hereby do not conflict with any other
registration rights granted by the Company. The Company will not enter into any
agreement which is inconsistent with or violates the rights granted to the
holders of Registrable Securities in this Agreement.

            (b) Remedies. Any Person having rights under any provision of this
Agreement will be entitled to enforce such rights specifically to recover
damages caused by reason of any breach of any provision of this Agreement and to
exercise all other rights granted by law. The parties hereto agree and
acknowledge that money damages may not be an adequate remedy for any breach of
the provisions of this Agreement and that any party may in its sole discretion
apply to any court of law or equity of competent jurisdiction (without posting
any bond or other security) for specific performance and for other injunctive
relief in order to enforce or prevent violation of the provisions of this
Agreement.

            (c) Amendments and Waivers. The provisions of this Agreement may be
amended or waived only upon the prior written consent of the Company and holders
of at least 75%


                                    - 18 -
   19

of the Registrable Securities; provided, that no amendment shall be effective
without the consent of a holder of Registrable Securities to the extent that
such amendment would adversely affect the rights or obligations of such holder
of Registrable Securities hereunder in any material respect, and any amendment
to which such written consent is obtained will be binding upon the Company and
all holders of Registrable Securities.

            (d) Successors and Assigns. All covenants and agreements in this
Agreement by or on behalf of any of the parties hereto will bind and inure to
the benefit of the respective successors and assigns of the parties hereto
whether so expressed or not. In addition, whether or not any express assignment
has been made, the provisions of this Agreement which are for the benefit of
purchasers or holders of Registrable Securities are also for the benefit of, and
enforceable by, any subsequent holder of Registrable Securities.

            (e) Severability. Whenever possible, each provision of this
Agreement will be interpreted in such manner as to be effective and valid under
applicable law, but if any provision of this Agreement is held to be prohibited
by or invalid under applicable law, such provision will be ineffective only to
the extent of such prohibition or invalidity, without invalidating the remainder
of this Agreement.

            (f) Counterparts. This Agreement may be executed simultaneously in
two or more counterparts, any one of which need not contain the signatures of
more than one party, but all such counterparts taken together will constitute
one and the same Agreement.

            (g) Descriptive Headings. The descriptive headings of this Agreement
are inserted for convenience only and do not constitute a part of this
Agreement.

            (h) Governing Law. The corporate law of the State of Idaho will
govern all questions concerning the relative rights of the Company and its
stockholders. All other questions concerning the construction, validity and
interpretation of this Agreement shall be governed by and construed in
accordance with the domestic laws of the State of New York, without giving
effect to any choice of law or conflict of law provision or rule (whether of the
State of New York or any other jurisdiction) that would cause the application of
the laws of any jurisdiction other than the State of New York.

                                    * * * * *


                                     - 19 -
   20

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


                                    MCMS, INC.



                                    By: /s/ Robert F. Subia
                                        ------------------------------------
                                          Name: Robert F. Subia
                                          Title: President and CEO


                                    CORNERSTONE EQUITY INVESTORS IV, L.P.

                                    By:   Cornerstone IV, L.L.C.,
                                          as General Partner



                                    By: /s/ Michael E. Najjor
                                        ------------------------------------
                                          Name: Michael E. Najjor
                                          Title: Managing Director


                                    MEI CALIFORNIA, INC.



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


                                    RANDOLPH STREET PARTNERS II



                                    By:   
                                        ------------------------------------
                                        A General Partner

   21
            
            IN WITNESS WHEREOF, the parties hereto have executed this
Registration Rights Agreement as of the date first above written.

                                    MCMS, INC.



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


                                    CORNERSTONE EQUITY INVESTORS IV, L.P.

                                    By:   Cornerstone IV, L.L.C.,
                                          as General Partner



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


                                    MEI CALIFORNIA, INC.



                                    By: /s/ T. Erik Oaas
                                        ------------------------------------
                                          Name: T. Erik Oaas
                                          Title: Executive Vice-President


                                    RANDOLPH STREET PARTNERS II



                                    By:   
                                        ------------------------------------
                                        A General Partner

   22
            
            IN WITNESS WHEREOF, the parties hereto have executed this
Registration Rights Agreement as of the date first above written.

                                    MCMS, INC.



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


                                    CORNERSTONE EQUITY INVESTORS IV, L.P.

                                    By:   Cornerstone IV, L.L.C.,
                                          as General Partner



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


                                    MEI CALIFORNIA, INC.



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


                                    RANDOLPH STREET PARTNERS II



                                    By: /s/ [Illegible]
                                        ------------------------------------
                                        A General Partner

   23

CONTINUATION OF SIGNATURES FOR THIS REGISTRATION RIGHTS AGREEMENT:


                                    BT INVESTMENT PARTNERS, INC.


                                    By: /s/ Joseph G. Wood
                                      ----------------------------------
                                          Name: JOSEPH G. WOOD
                                          Title: M. D.


                                    OTHER INVESTORS


                                    ------------------------------------
                                    Chris Anton


                                    ------------------------------------
                                    Jess Asla


                                    ------------------------------------
                                    John McCarvel


                                    ------------------------------------
                                    Robert F. Subia


                                    ------------------------------------
                                    R. Stephen Cheheyl


                                    ------------------------------------
                                    Finis Connor


                                    ------------------------------------
                                    Nicholas Keating
   24

CONTINUATION OF SIGNATURES FOR THIS REGISTRATION RIGHTS AGREEMENT:


                                    BT INVESTMENT PARTNERS, INC.


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


                                    OTHER INVESTORS


                                    /s/ Chris Anton
                                    ------------------------------------
                                    Chris Anton


                                    ------------------------------------
                                    Jess Asla


                                    ------------------------------------
                                    John McCarvel


                                    ------------------------------------
                                    Robert F. Subia


                                    ------------------------------------
                                    R. Stephen Cheheyl


                                    ------------------------------------
                                    Finis Connor


                                    ------------------------------------
                                    Nicholas Keating
   25

CONTINUATION OF SIGNATURES FOR THIS REGISTRATION RIGHTS AGREEMENT:


                                    BT INVESTMENT PARTNERS, INC.


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


                                    OTHER INVESTORS


                                    ------------------------------------
                                    Chris Anton


                                    /s/ Jess Asla
                                    ------------------------------------
                                    Jess Asla


                                    ------------------------------------
                                    John McCarvel


                                    ------------------------------------
                                    Robert F. Subia


                                    ------------------------------------
                                    R. Stephen Cheheyl


                                    ------------------------------------
                                    Finis Connor


                                    ------------------------------------
                                    Nicholas Keating
   26

CONTINUATION OF SIGNATURES FOR THIS REGISTRATION RIGHTS AGREEMENT:


                                    BT INVESTMENT PARTNERS, INC.


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


                                    OTHER INVESTORS


                                    ------------------------------------
                                    Chris Anton


                                    ------------------------------------
                                    Jess Asla


                                    /s/ John McCarvel
                                    ------------------------------------
                                    John McCarvel


                                    ------------------------------------
                                    Robert F. Subia


                                    ------------------------------------
                                    R. Stephen Cheheyl


                                    ------------------------------------
                                    Finis Connor


                                    ------------------------------------
                                    Nicholas Keating
   27

CONTINUATION OF SIGNATURES FOR THIS REGISTRATION RIGHTS AGREEMENT:


                                    BT INVESTMENT PARTNERS, INC.


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


                                    OTHER INVESTORS


                                    ------------------------------------
                                    Chris Anton


                                    ------------------------------------
                                    Jess Asla


                                    ------------------------------------
                                    John McCarvel


                                    /s/ Robert F. Subia
                                    ------------------------------------
                                    Robert F. Subia


                                    ------------------------------------
                                    R. Stephen Cheheyl


                                    ------------------------------------
                                    Finis Connor


                                    ------------------------------------
                                    Nicholas Keating
   28

CONTINUATION OF SIGNATURES FOR THIS REGISTRATION RIGHTS AGREEMENT:


                                    BT INVESTMENT PARTNERS, INC.


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


                                    OTHER INVESTORS


                                    ------------------------------------
                                    Chris Anton


                                    ------------------------------------
                                    Jess Asla


                                    ------------------------------------
                                    John McCarvel


                                    ------------------------------------
                                    Robert F. Subia


                                    /s/ R. Stephen Cheheyl
                                    ------------------------------------
                                    R. Stephen Cheheyl


                                    ------------------------------------
                                    Finis Connor


                                    ------------------------------------
                                    Nicholas Keating
   29

CONTINUATION OF SIGNATURES FOR THIS REGISTRATION RIGHTS AGREEMENT:


                                    BT INVESTMENT PARTNERS, INC.


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


                                    OTHER INVESTORS


                                    ------------------------------------
                                    Chris Anton


                                    ------------------------------------
                                    Jess Asla


                                    ------------------------------------
                                    John McCarvel


                                    ------------------------------------
                                    Robert F. Subia


                                    ------------------------------------
                                    R. Stephen Cheheyl


                                    /s/ Finis Connor
                                    ------------------------------------
                                    Finis Connor


                                    ------------------------------------
                                    Nicholas Keating
   30

CONTINUATION OF SIGNATURES FOR THIS REGISTRATION RIGHTS AGREEMENT:


                                    BT INVESTMENT PARTNERS, INC.


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


                                    OTHER INVESTORS


                                    ------------------------------------
                                    Chris Anton


                                    ------------------------------------
                                    Jess Asla


                                    ------------------------------------
                                    John McCarvel


                                    ------------------------------------
                                    Robert F. Subia


                                    ------------------------------------
                                    R. Stephen Cheheyl


                                    ------------------------------------
                                    Finis Connor


                                    /s/ Charles Nicholas Keating
                                    /s/ Carleen B. Keating
                                    ------------------------------------
                                    Charles Nicholas Keating, Jr  AND
                                    Carleen B. Keating, JT/WROS
   31

                                    OAK INVESTMENT PARTNERS VII, LIMITED
                                    PARTNERSHIP

                                    By:  Oak Associates VII, LLC


                                    By:  /s/ Fredric W. Harman
                                         ---------------------------------------
                                         Name:  Fredric W. Harman
                                         Title: Managing Member


                                    OAK VII AFFILIATE FUND, LIMITED
                                    PARTNERSHIP

                                    By:  Oak VII Affiliates, LLC


                                    By:  /s/ Fredric W. Harman
                                         ---------------------------------------
                                         Name:  Fredric W. Harman
                                         Title: Managing Member



                                    --------------------------------------------
                                    Norman Nie


                                    AUGUST CAPITAL, L.P. for itself and as
                                    nominee for August Capital Strategic
                                    Partners, L.P. and August Capital
                                    Associates, L.P.

                                    By: August Capital Management, L.L.C.,
                                        its general partner


                                    By:
                                         ---------------------------------------
                                         Name: Mark G. Wilson
                                         Title: Member


                                      - 22 -
   32

                                    OAK INVESTMENT PARTNERS VII, LIMITED
                                    PARTNERSHIP

                                    By:  Oak Associates VII, LLC


                                    By:
                                         ---------------------------------------
                                         Name:  Fredric W. Harman
                                         Title: Managing Member


                                    OAK VII AFFILIATE FUND, LIMITED
                                    PARTNERSHIP

                                    By:  Oak VII Affiliates, LLC


                                    By:
                                         ---------------------------------------
                                         Name:  Fredric W. Harman
                                         Title: Managing Member


                                    /s/ Norman Nie
                                    --------------------------------------------
                                    Norman Nie


                                    AUGUST CAPITAL, L.P. for itself and as
                                    nominee for August Capital Strategic
                                    Partners, L.P. and August Capital
                                    Associates, L.P.

                                    By: August Capital Management, L.L.C.,
                                        its general partner


                                    By:
                                         ---------------------------------------
                                         Name: Mark G. Wilson
                                         Title: Member


                                      - 22 -
   33

                                    OAK INVESTMENT PARTNERS VII, LIMITED
                                    PARTNERSHIP

                                    By:  Oak Associates VII, LLC


                                    By:
                                         ---------------------------------------
                                         Name:  Fredric W. Harman
                                         Title: Managing Member


                                    OAK VII AFFILIATE FUND, LIMITED
                                    PARTNERSHIP

                                    By:  Oak VII Affiliates, LLC


                                    By:
                                         ---------------------------------------
                                         Name:  Fredric W. Harman
                                         Title: Managing Member



                                    --------------------------------------------
                                    Norman Nie


                                    AUGUST CAPITAL, L.P. for itself and as
                                    nominee for August Capital Strategic
                                    Partners, L.P. and August Capital
                                    Associates, L.P.

                                    By: August Capital Management, L.L.C.,
                                        its general partner


                                    By:  /s/ Mark G. Wilson
                                         ---------------------------------------
                                         Name: Mark G. Wilson
                                         Title: Member


                                      - 22 -
   34

                                  APPENDIX A

Chris Anton

Jess Asla

August Capital, L.P. for itself and as nominee for August Capital Strategic
Partners, L.P. and August Capital Associates, L.P.

R. Stephen Cheheyl

Finis Connor

Nicholas Keating

John McCarvel

Norman Nie

Oak VII Affiliate Fund, Limited Partnership

Oak Investment Partners VII, Limited Partnership

Robert F. Subia