Document:

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                                                                   Exhibit 10.66

August 10, 2000

L. William McIntosh
31201 Paseo Miraloma
San Juan Capistrano, California 92675

    Re:    Acceptance of Consulting Arrangement and Resignation, Severance
           ---------------------------------------------------------------
    Agreement and General Release
    -----------------------------

Dear Bill:

This letter confirms the acceptance of your consulting arrangement and
resignation from employment with Nexell of California, Inc., formerly known as
Nexell Therapeutics Inc., ("Nexell") effective July 14, 2000 ("Resignation
Date"). Effective your Resignation Date, you have resigned from all officer and
director positions you hold with Nexell, including your duties as President and
Chief Executive Office ("CEO") of Nexell. You have also resigned from all
officer positions held with Nexell's parent corporation, Nexell Therapeutics
Inc. (formerly known as VIMRx Pharmaceuticals Inc.) ("Nexell Parent"), including
your duties as President and Chief Operating Officer ("COO") of Nexell Parent,
but you have not resigned as a director of Nexell Parent. (For purposes of this
letter, Nexell, Nexell Parent and all their related, affiliated, parent or
subsidiary entites are collectively referred to as the "Nexell Entities.") You
have further resigned any other officer or director positions you hold with any
other Nexell Entities. Set forth below are the terms of your Severance Agreement
and General Release and Consulting Agreement ("Agreement") with the Nexell
Entities. You understand and agree that you have waived notice to any proceeding
before Nexell Parent's Board of Directors ("Board") to discuss the terms of
these agreements.

                             Consulting Agreement
                             --------------------

     1.   You agree to provide advisory and consulting services for the Nexell
Entities as requested by the CEO or COO of Nexell Parent for a period of
fourteen (14) months from your Resignation Date, until September 14, 2001
("Consulting Period"). You agree to make yourself available not less than two
days per week during the Consulting Period, unless prior to the end of the
Consulting Period, you are engaged as a full time employee for another entity.
You acknowledge that your consulting services are not intended to include
services you render as a director of Nexell Parent, and you will not be
compensated for services you render as a director of Nexell Parent.

     2.   You shall be compensated for consulting services at a daily rate of
$1,000.00 per day for each day of service (or any portion thereof) specifically
requested by the CEO or COO of Nexell Parent. The Nexell Entities shall use your
services as a consultant for a minimum of thirty (30) days during the Consulting
Period or, alternatively, pay you at the end of the Consulting Period the
difference between the amount of $30,000.00 and the amount actually received by
you for consulting services under this Consulting Agreement if that amount is
less than $30,000.00. You shall also be reimbursed for all reasonable
out-of-pocket expenses incurred by you in performing services under this
Consulting Agreement. Any consulting fees earned or reasonable expenses

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incurred by you shall be paid on a monthly basis in accordance with Nexell's
ordinary accounts payable practices after receipt of a statement from you.
Nexell shall have the right to audit and review the reasonableness of your
expense claims.

     3.   You agree that the intent of this Consulting Agreement is for you to
provide services to the Nexell Entities as an independent contractor. Nothing in
this Consulting Agreement shall be interpreted or construed as creating or
establishing the relationship of employee or employee between you (and your
employees or agents) and any of the Nexell Entities. You shall be solely and
entirely responsible for your acts and the acts of your employees, agents or
subcontractors. You retain the sole and exclusive right to control or direct the
manner or means by which the consulting services are to be performed, except
that your services shall be rendered in a timely and professional manner at such
places and during such hours as you and the CEO or COO of Nexell Parent may
determine consistent with the needs of the project as defined by the CEO or COO
of Nexell Parent. You will provide the supplies and equipment necessary to
perform the services requested. The Nexell Entities will provide you with
reasonable access to the information and facilities necessary to enable you to
perform services under this Consulting Agreement.

     4.   The Nexell Entities will not have an exclusive right to your services
during the Consulting Period, and you shall retain the right to perform services
for others during the Consulting Period, provided such services (a) are not
competitive with the Nexell Entities and (b) do not involve you in a conflict of
interest with respect to the consulting arrangements set forth in this
Consulting Agreement. The Nexell Entities are free to utilize the services of
others during the Consulting Period.

     5.   Because you are engaged as an independent contractor and not an
employee, you will not be eligible to participate in employee benefits, leaves
of absence or other programs that are now or may be provided by the Nexell
Entities to their employees, except as expressly stated in the Severance
Agreement below.

     6.   Because you are engaged as an independent contractor and not an
employee, no payment received by you pursuant to this Consulting Agreement shall
be subject to employment tax withholding, nor shall the Nexell Entities withhold
or pay federal social security tax (FICA), Medicare tax, or federal or state
income tax, or make contributions to the federal or state unemployment or
disability insurance funds on your behalf. You are responsible for filing all
income and other tax forms and paying all taxes due.

     7.   You acknowledge that you will not be covered by Nexell's worker's
compensation insurance should you be injured while performing services under
this Consulting Agreement, and you agree that you will maintain health insurance
for yourself during the term of the Consulting Agreement either by maintaining
your group health insurance in effect pursuant to paragraph 13 below or by
obtaining major medical health insurance coverage from some alternative source.

     8.   This Consulting Agreement is assignable by the Nexell Entities upon
written notice to you. However, since the services to be rendered by you are
personal in nature, this Consulting Agreement may not be assigned by you without
the written consent of the CEO or COO of Nexell Parent. You also may not use
your employees, agents or subcontractors to perform services under this
Consulting Agreement without the express, written consent of the CEO or COO of
Nexell Parent.

     9.   You acknowledge and agree that you have no authority to enter into
contracts or

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agreements on behalf of the Nexell Entities, or to represent the Nexell Entities
as an agent or in any other capacity without the express written consent of the
CEO or COO of Nexell Parent.

                    Severance Agreement and General Release
                    ---------------------------------------

     10.  You will continue to be paid your base salary through September 30,
2000 in accordance with Nexell's ordinary payroll practices. You will continue
to be eligible to participate in Nexell's group benefit plans and 401(k) plan in
accordance with plan terms and you will continue to accrue vacation through
September 30, 2000. You will also be paid for any accrued, but unused, vacation
through September 30, 2000.

     11.  Commencing on October 1, 2000 and ending on September 30, 2001, Nexell
shall pay you a severance payment equivalent to twelve months of your current
annual base salary of $21,091.20 per month for a total of $253,094.40, less
applicable state and federal withholdings and deductions. These payments shall
be made in semi-monthly installments in accordance with Nexell's ordinary
payroll practices. Except for the one-time bonus described in paragraph 12 below
and the compensation described in the Consulting Agreement above, you shall
receive no further compensation of any kind from the Nexell Entities. During
this twelve-month severance period, you shall not be eligible to receive the
annual cash bonus or to participate in any benefit plans offered employees of
the Nexell Entities unless expressly provided for in this letter. In particular,
you shall not accrue paid vacation, nor shall you be eligible to participate in
Nexell's 401(k) Plan.

     12.  You shall be paid a one-time bonus of $50,000.00, less applicable
withholdings. The bonus shall be paid at the time bonuses are regularly paid to
Nexell's officers, but in no event shall it be paid later than February 27,
2001. You understand and agree that, except as provided in this paragraph, you
will not be paid any other bonuses by the Nexell Entities, including the annual
cash bonus provided for in paragraph 2(d) of your Employment Agreement with
Nexell dated May 28, 1998 ("Employment Agreement").

     13.  As of September 30, 2000, your rights if any, regarding continuation
of group health insurance coverage will be governed by COBRA. Under separate
cover you will receive COBRA information, which will include the notice of your
rights to elect continuation coverage under COBRA for medical and dental
insurance. In this regard, you may elect, in accordance with a federal statute
(COBRA), to continue your medical and dental benefits for up to 18 months
following September 30, 2000. Through September 30, 2001, you and Nexell will
share the cost of medical and dental premiums. You must pay the full COBRA cost
for the remaining six months of the COBRA coverage period. Thus, for the period
July 19, 2000 through September 30, 2001, you will pay or have deducted on your
behalf the employee co-pay portion of such benefits, which is approximately
fifteen (15) percent of the premiums paid by Nexell for such benefits. In the
event Nexell changes or discontinues its medical and dental coverage prior to
September 30, 2001, you agree to accept such coverage as Nexell provides for its
officers.

     14.  In accordance with Nexell's relocation policy for executives of your
status, Nexell will pay or reimburse you for the reasonable expenses of
relocating your household to southeastern Pennsylvania. Should you choose to
return to southeastern Pennsylvania, your relocation must be completed and
expenses submitted by December 31, 2001 to be eligible for reimbursement. Such
relocation expenses will be similar in nature, amount and quality as were
previously reimbursed to you in making your move to California, with the
following exceptions: (a) Nexell will not pay any temporary living or storage
expenses you incur upon relocation to Pennsylvania; (b) Nexell will only pay
reasonable non-recurring closing costs; and (c) Nexell will

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only pay the cost of up to two round trip economy airline tickets for travel to
Pennsylvania by you and your wife. To the extent that any of the expenses paid
or reimbursed by Nexell pursuant to this paragraph constitute compensation
income to you that is subject to personal income taxation, Nexell will pay the
aggregate federal, state and local income taxes payable by you with respect to
the compensation income attributable to the payment or reimbursement of such
expenses by Nexell (including income taxes payable with respect to such
additional cash compensation).

     15.  Nexell and Nexell Parent hereby acknowledge that you now possess
fully vested options to purchase 183,750 shares of Nexell Parent's common stock,
at the option prices and for the exercise periods reflected on Exhibit A.

     16.  Nexell and Nexell Parent shall use commercially reasonable efforts to
list you as an additional insured on their Directors & Officers policies
presently in effect or in the future, provided that Nexell and Nexell Parent
shall not be obligated to do so in the event: (a) such listing imposes an
additional expense to Nexell and Nexell Parent (which you chose not to pay); (b)
the insurer will not permit such additional listing; or (c) such listing would
require Nexell and Nexell Parent to obtain a policy different than a policy that
it would elect to obtain covering all of its officers or directors.

     17.  In exchange for the payments and benefits to be received under the
Consulting Agreement, the sufficiency of which you hereby acknowledge, you, for
yourself, your heirs, successors, and assigns (collectively referred to as
"Releasors"), do irrevocably and unconditionally release, acquit, and forever
discharge the Nexell Entities, and each of their related or affiliated entities,
and each of their past and present officers, owners, directors, shareholders,
employees, agents, contractors, representatives, attorneys, predecessors,
successors and assigns (all of whom are collectively referred to as
"Releasees"), and all persons acting by, through, under or in concert with any
of them, or any of them, from any and all claims, charges, complaints, rights,
demands, actions, causes of action, whether known or unknown, which you may now
have, have ever had, or may in the future have, arising from or in any way
connected with any and all matters from the beginning of time to the date of
execution of this Agreement. You give up any and all causes of action of any and
every kind, including, without limitation, any claims for discrimination or
retaliation prohibited under the California Fair Employment and Housing Act
(California Government Code (S). 12900 et seq.), Title VII of the United States
Civil Rights Act of 1964, as amended (42 U. S. C. (S) 2000e et seq.), and the
Age Discrimination in Employment Act; wrongful termination in violation of
public policy, breach of the Employment Agreement or amendments thereto, breach
of the stock option agreements or amendments thereto, breach of contract,
whether oral or written, express or implied, breach of any implied covenant of
good faith and fair dealing, misrepresentation, negligent or intentional
infliction of emotional distress; any form of negligence; fraud; deceit; or
violation of any other federal, state, county, or municipal law, statute,
regulation, rule, ordinance, or common law doctrine (whether or not recited
herein), arising out of or related to your employment by or with any of the
Releasees.

     18.  To effect a full and complete release as described above, you, for
yourself and your heirs, successors, assigns, agents, and all persons or
entities associated with you, expressly waive and relinquish all rights and
benefits afforded you by section 1542 of the Civil Code of the State of
California, and do so understanding and acknowledging the significance and
consequence of such specific waiver of section 1542. Section 1542 of the Civil
Code of the State of California states as follows: "A general release does not
extend to claims which the creditor does not know or suspect to exist in his
favor at the time of executing the release, which, if known by him must have
materially affected his settlement with the debtor".

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You agree that, you have read this Agreement, including the waiver of California
Civil Code section 1542, and have consulted counsel about the Agreement to the
extent you so desire and specifically about the waiver of section 1542, and that
you understand the Agreement and the section 1542 waiver, and so freely and
knowingly enter into this Agreement, and waive your rights under said section
1542.

     19.  During your employment with Nexell, you have had access to
confidential and proprietary information. Nexell maintains a proprietary
interest in all such confidential data. Accordingly, it is expected that you
will not use or disclose to any entity or person, either directly or indirectly,
this confidential information.

          (a)  For a period of six months from your Resignation Date, you
will not directly or indirectly own, manage, operate, join, control or become
employed by, or render any services of an advisory nature or otherwise, or
participate in the ownership, management, operation or control of, or otherwise
be connected in any manner with any business competitive with the business of
the Nexell Entities or any of its directly or indirectly, wholly or partially
owned subsidiaries without prior written consent of the CEO or COO of Nexell
Parent.

          (b)  You further hereby covenant and agree that you will not at any
time during, or (i) for a period of three (3) years following your Resignation
Date reveal, divulge or make known to any person or entity any secrets or
confidential information (whether oral, written, or electronically encoded)
whatsoever, of or concerning the Nexell Entities or any of its directly or
indirectly, wholly or partially owned subsidiaries or its business or anything
connected therewith, all of which is and shall remain the property of the Nexell
Entities and shall be returned by you to the Nexell Entities (including all
copies) immediately upon any termination of your employment (or earlier, if
requested by the Nexell Entities), or (ii) for a period of three (3) years
following your Resignation Date directly or indirectly entice away from the
employment of the Nexell Entities, retain or otherwise engage, any employee of
the Nexell Entities, or attempt to do any of the foregoing; provided, however,
nothing herein shall prevent you from interviewing and/or ultimately retaining
someone who has already left the employment of any Nexell entity as of your
Resignation Date, or who has left the employment of any Nexell entity for at
least three months prior to being retained or hired by you.

          (c)  For purposes hereof, confidential information shall not include
any information which: (i) is or becomes generally available to the public other
than as a result of a wrongful disclosure by you or your representatives; (ii)
was known by you on a non-confidential basis prior to its disclosure to you by
the Nexell Entities or their representatives; (iii) becomes available to you
from a source other than the Nexell Entities or its representatives, provided
that such source is not bound by a confidentiality agreement with the Nexell
Entities or their representatives and otherwise has a right to disclose the
same: or (iv) is required to be disclosed by any governmental or judicial
authority, provided, in such case, that you shall use your best efforts to
notify the Nexell Entities immediately of any such requirement so that the
Nexell Entities shall have an opportunity to contest it.

          (d)  In the event of any breach or threatened breach by you of any one
or more of the provisions of this paragraph 19, the Nexell Entities will be
entitled, in addition to any remedy hereunder or under any applicable law or in
equity, to an injunction restraining the breach of such provisions hereof.

     20.  You represent and agree that, except as set forth herein, you will
keep the existence, the terms, and amount of this Agreement completely
confidential. You may disclose the amount and

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terms of this Agreement to members of your immediate family, attorneys,
accountants, or as otherwise expressly required or compelled by law. You
understand and acknowledge that this paragraph constitutes an essential and
material part of this Agreement. Notwithstanding any other provision hereof;
this Agreement may be disclosed in any action brought to remedy a breach of this
Agreement. You further understand that the contents of this Agreement may be
disclosed by Nexell Parent and the Agreement itself filed with the Securities
and Exchange Commission in accordance with applicable securities laws.

     21.  You agree that you will not voluntarily assist any person in bringing
or pursuing legal action against the Nexell Entities, their agents, successors,
representatives, employees and related and/or affiliated companies, based on
events occurring prior to the date of this Agreement.

     22.  You further agree as a condition of receiving the benefits provided to
you under this Agreement: (a) not to disparage any of the Nexell Entities or
their employees or products; (b) not to engage in a series of actions which you
know or should know are contrary to the interest of any of the Nexell Entities;
(c) from today's date through September 30, 2001, to fully cooperate with the
Nexell Entities and their directors, officers, employees, attorneys and
representatives by providing assistance or information in your capacity as a
director of Nexell Parent or as requested from time to time by Nexell Parent's
CEO or COO, pursuant to the Consulting Agreement; and (d) to return to the
Nexell Entities, on or before your Resignation Date, all property of the Nexell
Entities, including proprietary information.

     23.  You shall continue to serve as a director on the Board of Nexell
Parent, except that you understand and agree that you will submit a letter of
resignation for this position if you are notified by a majority of the Board
that the Board deems it in the best interest of Nexell Parent for you to resign
your position. You are not obligated to stand for reelection and serve beyond
your current term on the Board.

     24.  You shall be entitled to outplacement services at Nexell's expense at
Right Management Consultants ("RMC") or a firm of your choice, but not to exceed
the additional out-of-pocket costs Nexell would have paid to RMC if you had
selected RMC for these services. Nexell has already paid or has committed to pay
an amount of approximately $25,000.00 to RMC for services which were to be
rendered for you. RMC has advised Nexell that it is willing to apply the
$25,000.00 amount against outplacement services for you. Nexell is willing to
contribute additional out-of-pocket costs of $5,000.00 to $10,000.00, depending
on the services you select. If you select an outplacement firm other than RMC,
Nexell shall pay to the alternative company an amount not to exceed $10,000.00
based upon the comparable outplacement services RMC would have provided you.

                              General Provisions
                              ------------------

     25.  By the actions and obligations set forth above, the Nexell Entities
admit no wrongdoing or liability. Further, this Agreement and Nexell's
acceptance of your resignation from employment do not in any way suggest any
violation of law by the Nexell Entities, but instead reflect a mutually agreed
upon transition for both you and the Nexell Entities.

     26.  You will have a period of twenty-one (21) days to review this
Agreement and the release of claims it contains. This Agreement will be
revocable for a period of seven (7) days from the date you sign it, provided
that you deliver written notice of revocation to me by the close of business on
the seventh (7th) day. If you revoke this Agreement, it will not be effective or
enforceable and Nexell will be under no obligation to provide the payments and
benefits referred to in this

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Agreement. If you do not revoke this Agreement as provided in this paragraph, it
shall be enforceable and irrevocable except by a written agreement signed by
both parties.

     27.  You agree and acknowledge that no promises have been made which are
not included in this Agreement and that, except as otherwise provided in this
Agreement, it supersedes all prior agreements between you and the Nexell
Entities and contains the entire understanding between you and the Nexell
Entities regarding the subject matter herein. You acknowledge that the terms of
this Agreement are contractually binding. If any portion of this Agreement is
declared invalid or unenforceable, the remaining portions of this Agreement will
continue in full force and effect. Any amendments to this Agreement must be in
writing and signed by all parties to this Agreement.

     28.  This Agreement is made and entered into in the State of California,
and shall in all respects be interpreted, enforced and governed under the laws
of said state.

Please read this letter carefully. By signing this letter, you give up any right
to sue the Nexell Entities or releasees for any reason, even reasons you do not
know about. If you agree to the terms outlined in this Agreement, then please
sign two copies and return one of them to me.

Sincerely,

Richard L. Dunning
Chairman of the Board and Chief Executive Officer
Nexell Therapeutics Inc.

ACCEPTED AND AGREED:

_______________________________
L. William McIntosh

_______________________________
Date

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                                                                   EXHIBIT 10.21

                      AMENDMENT NO. 1 to SUPPLY AGREEMENT
                      -----------------------------------
                  BETWEEN GRUPO IUSACELL CELULAR S.A. DE C.V.
                  -------------------------------------------
                    AND METAWAVE COMMUNICATIONS CORPORATION
                    ---------------------------------------

This Amendment No. 1 is made as of August 16, 2000 to the Supply Agreement by
and between Grupo Iusacell Celular S.A. de C.V . ("Customer") (previously named
Grupo Iusacell S.A. de C.V.) and Metawave Communications Corporation ("Seller"),
dated December 17, 1999 (the "Agreement").  All defined terms used in this
Amendment shall have the same meanings as in the Agreement, unless otherwise
indicated.

WHEREAS, Customer has agreed to purchase [*] of Products from Seller for
delivery by [*] pursuant to the Agreement;

WHEREAS, Seller has agreed to provide to Customer amended financial terms for
payment of those Products, provided that [*]

WHEREAS both parties wishes to amend several Sections of the Agreement in order
to read as follows.

NOW, THEREFORE, THE PARTIES AGREE:

1.   Section 3(e) of the Agreement is replaced in its entirety by the following:

     Customer may cancel or delay delivery of Products contained in any Purchase
     Order or Change Order prior to Seller's shipment of the Products subject to
     the terms herein.  Any such cancellation or delay must be made by written
     notification to Seller.  Customer may delay the delivery date for any
     Products on any Purchase Order or Change Order, provided that such delay
     shall not exceed [*] days.  Customer endeavors not to cancel or delay any
     Purchase Order or Change Order with less than [*] days written notice from
     the delivery date specified in the Purchase Order or Change Order.

2.   Section 4(a) of the Agreement is replaced in its entirety by the following:

     Subject to Section 3, Seller shall ship in accordance with Seller's
     standard shipping practices all Products to Customer's designated
     representative at the designated delivery destination on or before the
     delivery date(s) specified in a Purchase Order.  Seller shall ship complete
     Products to Laredo, Texas as specified by Customer in the Purchase Order or
     otherwise agreed in writing by Customer and Seller.  If any Products
     require temporary warehousing in Laredo as a result of incomplete
     shipments, or by any direct or indirect acts or omissions attributable to
     Seller (i.e. documents incomplete or inaccurate), Seller shall bear all
     costs and expenses of such warehousing.  Seller shall not be responsible
     for shipping Products into Mexico or for any compliance with Mexican import
     or customs requirements, other than those necessary for the Customer to
     import the Products

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     into Mexico, including documentation required by the North American Free
     Trade Agreement.

     [*]

3.   Section 4(d) of the Agreement is replaced in its entirety by the following:

     Title to and risk of loss or damage to Products sold by Seller to Customer
     hereunder shall pass to Customer upon delivery to Customer's representative
     at the delivery destination specified on the Purchase Order, except that
     with respect to Products which are warehoused pursuant to section 4(a)
     hereof as a result of incomplete shipment or documentation, title and risk
     of loss shall pass to Customer when the Products and related documentation
     are complete. Title to Software shall remain with Seller in all cases
     pursuant to the terms of the Software License attached as Exhibit D hereto.

4.  Section 5(a) of the Agreement is replaced in its entirety by the following:

     In the event that Customer orders installation and commissioning services
     by Seller, Seller shall install and commission each Product in accordance
     with a mutually agreed upon deployment schedule. Customer agrees to furnish
     reasonable access to the cell sites and the necessary resources to assist
     Seller during installation and optimization. Such deployment schedule shall
     be agreed to in writing by Seller and Customer.

5.   Section 5(b) of the Agreement is replaced in its entirety by the following:

     If Seller fails to complete installation and commissioning of a Product
     within the specified deadline (or any extension agreed to in writing by the
     parties), and such failure is due to delays or causes directly or
     indirectly attributable to Seller, then Seller will not charge Customer for
     the installation and commissioning of that Product at the designated site.
     In the event of any delay beyond the reasonable control of Seller, the
     date(s) of installation and commissioning shall be extended for as many
     days as are reasonably required due to the delay.

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6.   Section 5(c) is replaced in its entirety by the following:

     If requested by Customer, Seller will offer Product training courses at
     Seller's own expense in Mexico at least 3 times per quarter during the
     period September 1, 2000 to September 30, 2001.  Each course will last no
     more than three days and will be for a minimum of five people and no more
     than ten people.  The schedule will be mutually agreed by the parties.  In
     addition, employees of Customer may train on an informal basis by observing
     and participating during installation and optimization of Products when
     such services are provided by Seller.  Seller will provide at no cost to
     Customer one set of manuals and documentation with each Product.

7.   Section 6(a) of the Agreement is replaced in its entirety by the following:

     Customer has agreed to purchase an amount [*] of Products pursuant to the
     terms and conditions set forth in the "Whereas" clauses of this Agreement.
     For Products to be installed by Seller, Seller shall render invoices to
     Customer as follows:  [*]

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8.   Section 6(b) of the Agreement is replaced in its entirety by the following:

     All invoices issued pursuant to Section 6(a) shall be computed on the basis
     of the prices set forth in Exhibit A [*] and shall separately identify
     categories of charges, including but not limited to quantities of Products,
     type of Services, total amounts for each item, shipping charges, applicable
     sales or use taxes and total amount due in U.S. dollars.

     For Products purchased pursuant to the terms and conditions set forth in
     the "Whereas" clauses of this Amendment, Customer shall promptly pay Seller
     the amount due on invoices within [*] of the date of invoice.  For all
     Services purchased by Customer and performed by Seller in the year 2000
     which are related to the Products purchased pursuant to the terms and
     conditions set forth in the "Whereas" clauses of this Amendment, and for
     which Customer has signed a Commissioning Certificate or an Engineering and
     Optimization Certificate, Seller shall invoice Customer [*]

9.   Section 6(c) is replaced in its entirety by the following:

     The prices specified in Exhibit A do not include any taxes.  Customer shall
     pay all local and government sales, excise, or any other taxes, fees,
     duties, tariffs, or other governmental charges or customs processing fees
     which may be levied upon the use, sale, transfer of ownership, or
     installation of Product or Services purchased hereunder or the import,
     movement, delivery, possession of Products, including the replacement and
     repair of Products, excluding, however, any taxes on the income, business
     or licenses of Seller.  Any such taxes or fees required to be paid or
     collected by Seller shall be added to the invoice as separate charges and
     paid by Customer to Seller unless Customer provides Seller with proof of
     exemption acceptable to the appropriate authority or in the event that
     Customer must withhold payment pursuant to the provisions of the Mexican
     Income Tax Law and/or the Treaty for Avoiding Double Taxation between
     Mexico and the United States (in which case Customer shall provide Seller
     with appropriate documentation so that Seller can claim any tax credit to
     which it may be entitled).

10.  Section 7(a) is replaced in its entirety by the following:

     Seller warrants the Products for a period of [*] ("Warranty Period").
     During the Warranty Period, Seller warrants that (i) all Products furnished
     hereunder will be

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     free from defects in materials, workmanship and title; (ii) all Products as
     delivered and properly installed and operated will function as described in
     the user documentation and specifications provided by Seller; and (iii) the
     media on which the Software is contained will be free from defects in
     material and workmanship under normal use.  THE WARRANTIES IN THIS
     AGREEMENT ARE GIVEN IN LIEU OF ALL OTHER WARRANTIES EXPRESS OR IMPLIED
     WHICH ARE SPECIFICALLY EXCLUDED, INCLUDING, WITHOUT LIMITATION, IMPLIED
     WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.

11.  Section 7(b) is replaced in its entirety by the following:

     Customer and Seller shall handle all warranty claims in accordance with the
     procedures set forth in Exhibit C, the Product Maintenance Program.  The
     actions taken by Seller under the Product Maintenance Program procedures
     shall be the full extent of Seller's liability and Customer's exclusive
     remedy with respect to a claim under this Section 7.  The supplied
     Products  provided hereunder by Seller to Customer  (i) shall perform on
     and after January 1, 2000 in as good a manner as before such date, and (ii)
     shall at all times manage, manipulate and report data involving dates
     (including the year 2000, dates before and after the year 2000, and single-
     century and multi-century formulas) without generating incorrect values or
     dates or causing an abnormally-ending scenario within an application
     without generating incorrect values or dates or causing an abnormally-
     ending scenario within an application.  Notwithstanding the above, Seller
     shall be liable to Customer for warranty claims under this Section up to an
     amount equal to the Purchase Order.

12.  Section 8(a) is replaced in its entirety by the following:

     Seller shall indemnify and hold harmless Customer against any and all
     liabilities, losses, costs, damages and expenses, including reasonable
     attorney's fees, associated with any claim or action for actual or alleged
     infringement by any Product or Software supplied in accordance with this
     Agreement of any patent, trademark, copyright, trade secret or other
     intellectual property right incurred by Customer as a result of Customer's
     use of such Products or Software in accordance with this Agreement provided
     that (i) Customer promptly notifies Seller in writing of the claim; (ii)
     Customer gives Seller full opportunity and authority to assume sole control
     of the defense and all related settlement negotiations; and (iii) Customer
     gives Seller information and assistance for the defense (Customer will be
     reimbursed for reasonable costs and expenses incurred in rendering such
     assistance, against receipt of invoices therefor) and (iv) such claim or
     action for actual or alleged infringement is being pursued or carried out
     by third parties with whom Seller, its parent, branches, subsidiaries,
     affiliates or any entity over which Seller has control, directly or
     indirectly, has any contractual relationship of any type.  Seller shall
     indemnify and hold harmless Customer from

                                      -5-
<PAGE>

     all payments, which by judgments in such claims, may be assessed against
     Customer on account of such alleged infringement and shall pay resulting
     settlements, costs and damages finally awarded against Customer by a court
     of law, arbitration or other adjudication of the claim.

13.  Section 8(c) is replaced in its entirety by the following:

     Seller shall have no obligation to Customer with respect to any claim of
     patent or copyright infringement which is based upon (i) adherence to
     specifications, designs or instructions furnished by Customer; (ii) the
     combination, operation or use of any Products supplied hereunder with
     products, software or data with which the Products are not intended to be
     used or for which the Products are not designed; (iii) the alteration of
     the Products or modification of any Software made by any party other than
     Seller; or (iv) the Customer's use of a release of some or all of the
     Software if infringement would have been avoided by the use of a subsequent
     unaltered release of the Software that is provided to the Customer.

14.  Section 9(a) is replaced in its entirety by the following:

     Seller shall indemnify Customer, its employees and directors, and each of
     them, against any loss, damage, claim, or liability, arising out of, as a
     result of, or in connection with the use of the Product in accordance with
     this Agreement or the acts or omissions, negligent or otherwise, of Seller
     in the performance of this Agreement, or a contractor or an agent of Seller
     or an employee of anyone of them, except where such loss, damage, claim, or
     liability arises from the gross negligence or willful misconduct of
     Customer, agents or its employees.  Seller shall, at its own expense,
     defend any suit asserting a claim for any loss, damage or liability
     specified above, and Seller shall pay any costs, expenses and attorneys'
     fees that may be incurred by Customer in connection with any such claim or
     suit or in enforcing the indemnity granted above, provided that Seller is
     given (i) prompt notice of any such claim or suit and (ii) full opportunity
     to assume control of the defense or settlement.

15.  Section 9(b) is replaced in its entirety by the following:

     Except with respect to claims pursuant to Section 8(a) of this Agreement,
     in no event will either party be liable under this Agreement for (i) the
     cost of substitute procurement, special, indirect, incidental, or
     consequential damages, or (ii) any damages resulting from the loss of use
     or profits arising out of or in connection with this Agreement, the
     furnishing of Services, or the use or performance of Products even if
     informed of the possibility of such damages.  Except for damages resulting
     from bodily injury or death to persons, and claims arising under Section
     8(a) of this Agreement, in no event will Seller's total liability for (i)
     any damages in any action based on or arising out of or in connection with
     this Agreement exceed the total amount paid to Seller for such Products
     under this Agreement, or

                                      -6-
<PAGE>

     (ii) claims based upon Seller's obligations for Services exceed the total
     amount paid to Seller for such Services.

16.  Section 11(a) is replaced in its entirety by the following:

     Any assignment by either party to this Agreement or any other interest
     hereunder without the other party's prior written consent, shall be void,
     except assignment to a parent company, subsidiary or person or entity who
     acquires all or substantially all of the assets, business or stock of
     either party, whether by sale, merger or otherwise provided that the
     assignee undertakes in writing to be obliged by the provisions of the
     Agreement, as amended.

17.  Section 12 is amended as follows:

     "....To Customer: Grupo Iusacell Celular S.A de C.V.... Attn: Henry
     Ruiz..."

18.  Section 14(c) is replaced in its entirety by the following:

     When Customer imports the Products into Mexico, Customer shall comply with
     all importation formalities and obtain any customs or regulatory permits
     required to import the Products into Mexico, including but not limited to
     NOM certificates issued by the Mexican Government through the Mexican
     Ministry of Commerce and Industrial Development relating to the compliance
     with electrical safety standards (NOM certificate). Seller agrees to
     indemnify Customer, its employees and directors, and each of them, against
     any loss, damage, claim or liability arising out of or as a result of, or
     in connection with the issuance of the NOM certificate to, and the holding
     or maintenance of the NOM certificate by, Customer except where such loss,
     damage, claim or liability arises from the gross negligence or willful
     misconduct of Customer, its agents or employees. Seller shall, at its own
     expense, defend any suit asserting a claim for any loss, damage or
     liability specified above, and Seller shall pay any costs, expenses and
     attorney's fees that may be incurred by Customer in connection with any
     such claim or suit or in enforcing the indemnity granted above, provided
     that Seller is given (i) prompt notice of any such claim or suit and (ii)
     full opportunity to assume control of the defense or settlement.

     In addition, Seller shall be responsible for maintaining the
     Products'compliance with applicable NOM standards and for conducting
     additional testing if needed to maintain the NOM certificate. Customer and
     Seller agree that the NOM certificate shall only be issued by Customer as
     the importer of Products for its own use, and that Seller shall not rely on
     the NOM certificate issued to Customer for importation on behalf of Seller
     or any other purchaser of the Products in Mexico.

19.  Section 15 is replaced in its entirety by the following:

                                      -7-
<PAGE>

     Except for payment of moneys due, neither party shall be liable for delays
     in delivery or performance or for failure to manufacture, deliver or
     perform resulting from acts beyond the reasonable control of the party
     responsible for performance.  Such acts shall include, but not be limited
     to (a) acts of God, acts of a public enemy, acts or failures to act by the
     other party, acts of civil or military authority, governmental priorities,
     strikes or other labor disturbances, hurricanes, earthquakes, fires,
     floods, epidemics, embargoes, war, riots, and loss or damage to goods in
     transit; (b) as a result of the foregoing events in subsection (a), the
     inability to obtain necessary products, components, services or facilities
     on account of causes beyond the reasonable control of the delayed party or
     its suppliers; or (c) delay in obtaining or the failure to obtain the
     necessary customs clearances, equipment authorizations, licenses, permits,
     governmental approvals and any other documentation required for the
     delivery, installation and operation of the Products at the Sites,
     including visas and work permits for Seller's personnel.  In the event of
     any such delay, the date(s) of delivery or performance shall be extended
     for as many days are reasonably required due to the delay.  If such delay
     continues for forty-five (45) days, either party may terminate the Purchase
     Order affected by the event by providing written notice. Notwithstanding
     the above, if the force majeure event could have been avoided by the prompt
     fulfillment of the obligations of the parties, it will not be considered as
     an event of force majeure.

20.  Section 16(b) is amended as follows:

     "Any dispute, controversy or claim arising out of or in connection with
     this Agreement, as amended, shall first be settled by non-binding mediation
     to be conducted in English by a mutually agreed non-affiliated neutral
     party. This mediation process shall commence within the next ten (10) days
     following the notification of the claim and shall be completed within the
     twenty (20) days following the notification of the claim. In the event
     mediation is unsuccessful or is not carried out for any reason within the
     above-referred time limits, the matter shall be finally settled by binding
     arbitration in New York, New York, under the rules of the International
     Chamber of Commerce in effect at the time of the arbitration to be
     conducted in English.  The arbitration decision shall be final and binding
     upon the parties and judgment upon the award rendered by the arbitrator may
     be entered in any court having jurisdiction thereof.  Notwithstanding the
     above, regarding intellectual property claims, Metawave reserves the right
     to initiate and conduct litigation proceedings in any court it deems
     appropriate.

21.  A new Section 20 is added to the Agreement as follows:

  SECTION 20. ADDITIONAL OBLIGATIONS OF SELLER

     a.   Seller shall [*]

[***] CERTAIN INFORMATION ON THIS PAGE(S) HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
THE OMITTED PORTIONS.

                                      -8-
<PAGE>

     b.   Seller shall [*]

          1.   [*] to coordinate all RF activities relating to Customer's
               Products, make recommendations to Customer for current and future
               Product applications and manage technical issues arising from
               Product installations and optimizations. This [*] may be extended
               by mutual agreement of the parties.

          2.   [*] to develop RF plans, perform initial optimization on Products
               after installation and perform the initial and ongoing evaluation
               of Product performance statistics.

          3.   [*] to coordinate all logistics, including shipping, installing
               and optimizing Customer's Products.

          4.   [*] to perform routine maintenance on Customer's Products and
               perform troubleshooting functions. These engineers will be
               dedicated to working [*] on Customer's Products and will be
               charged to Customer pursuant to [*]. Such services will be
               invoiced upon completion of the services and shall be payable
               within [*] days of the date of invoice.

     c.   Seller may use the above personnel (except for the maintenance
          engineers whose time is charged to customers) on other non-Customer
          projects provided that such redeployment does not affect service
          quality to Customer.

     d.   [*] Seller shall provide Customer with a written procedure for
          submitting, tracing and resolving technical Product problems,
          including Product modifications and bug fixes.  Such procedures shall
          include an escalation procedure.

     e.   Seller agrees to discuss with Customer the possibility of Seller
          providing turnkey services to Customer which would include site
          preparation, RF engineering services and antenna installation. Such
          services, if offered, would be invoiced upon completion of the
          services and be payable within [*] of the date of invoice.

     f.   Seller will provide a monitoring and alarm facility within Customer's
          network operations center (NOC) for all Products that have SiteNet
          installed and operational at a price to be mutually agreed by the
          parties.

[***] CERTAIN INFORMATION ON THIS PAGE(S) HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
THE OMITTED PORTIONS.

                                      -9-
<PAGE>

22.  Exhibit A of the Agreement is amended as follows:

     [*]

23.  All other terms and conditions of the Agreement remain the same.

Metawave Communications Corporation         Grupo Iusacell Celular S.A. de C.V.

By: /s/ Richard Henderson                   By: /s/ Henry Ruiz
   --------------------------------            ---------------------------------

Name: Richard Henderson                     Name: Henry Ruiz

Title: VP, Sales and Marketing              Title: VP, Network Operations

[***] CERTAIN INFORMATION ON THIS PAGE(S) HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
THE OMITTED PORTIONS.

                                      -10-

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