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                                                                   EXHIBIT 10.12



                          SECURITIES PURCHASE AGREEMENT


               THIS SECURITIES PURCHASE AGREEMENT, dated as of the date of
acceptance set forth below, is entered into by and between ESAT, INC., a Nevada
corporation, with headquarters located at 16520 Harbor Boulevard, Bldg. G,
Fountain Valley, California 92708(the "Company"), and each entity named on a
signature page hereto (each, a "Buyer") (each agreement with a Buyer being
deemed a separate and independent agreement between the Company and such Buyer,
except that each Buyer acknowledges and consents to the rights granted to each
other Buyer under such agreement and the Transaction Agreements, as defined
below, referred to therein).

                              W I T N E S S E T H:

               WHEREAS, the Company and the Buyer are executing and delivering
this Agreement in accordance with and in reliance upon the exemption from
securities registration afforded, inter alia, by Rule 506 under Regulation D
("Regulation D") as promulgated by the United States Securities and Exchange
Commission (the "SEC") under the Securities Act of 1933, as amended (the "1933
Act"), and/or Section 4(2) of the 1933 Act; and

               WHEREAS, the Buyer wishes to purchase, upon the terms and subject
to the conditions of this Agreement, Series C 6% Convertible Preferred Stock of
the Company (the "Convertible Preferred Stock") which will be convertible into
shares of Common Stock, $.001 par value per share, of the Company (the "Common
Stock"), upon the terms and subject to the conditions of such Convertible
Preferred Stock , together with the Warrants (as defined below) exercisable for
the purchase of shares of Common Stock, and subject to acceptance of this
Agreement by the Company;

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

               1. AGREEMENT TO PURCHASE; PURCHASE PRICE.

               a. PURCHASE.

               (i) The undersigned hereby agrees to purchase from the Company
Convertible Preferred Stock in the principal amount set forth on the signature
page of this Agreement (the "Preferred Stock") out of a total offering of not
more than $5,000,000 of such Convertible Preferred Stock, and having the terms
and conditions and being in the form attached hereto as ANNEX I(A).

               (ii) Subject to the terms and conditions of this Agreement and
the other



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Transaction Agreements, the Buyer will purchase (x) the Preferred Stock on the
Closing Date (as defined below).

               (iii) The purchase price to be paid by the Purchaser shall be
equal to the face amount of the Preferred Stock being purchased on the relevant
Closing Date (as defined below) and shall be payable in United States Dollars.

               b. CERTAIN DEFINITIONS. As used herein, each of the following
terms has the meaning set forth below, unless the context otherwise requires:

               (i) "Preferred Stock" means all or any portion of the Preferred
Stock.

               (ii) "Securities" means the Preferred Stock, the Warrants and the
Common Stock issuable upon conversion of the Preferred Stock or the exercise of
the Warrants.

               (iii) "Purchase Price" means the purchase price for the Preferred
Stock.

               (iv) " Closing Date" means the date of the closing of the
purchase and sale of the Preferred Stock, as provided herein.

               (v) "Closing Date" means the Closing Date.

               (vi) "Effective Date" means the effective date of the
Registration Statement covering the Registrable Securities (as those terms are
defined in the Registration Rights Agreement defined below) for the Preferred
Stock and Warrants issued on the Closing Date.

               (vii) "Market Price of the Common Stock" means (x) the closing
bid price of the Common Stock for the trading day ending on the trading day
immediately before the relevant date indicated in the relevant provision hereof
(unless a different relevant period is specified in the relevant provision), as
reported by Bloomberg, LP or, if not so reported, as reported on the
over-the-counter market or (y) if the Common Stock is listed on a stock
exchange, the closing price on such exchange on the trading day immediately
before the relevant date indicated in the relevant provision hereof (unless a
different relevant period is specified in the relevant provision), as reported
in The Wall Street Journal.

               (xi) "Converted Shares" means the shares of Common Stock issuable
upon conversion of the Preferred Stock.

               (xii) "Warrant Shares" means the shares of Common Stock issuable
upon exercise of the Warrants.

               (xiii) "Shares" means the shares of Common Stock representing any
or all of the Converted Shares and the Warrant Shares.



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               (xiv) "Certificates" means the relevant Preferred Stock and the
relevant Warrants, each duly executed on behalf of the Company and issued in the
name of the Buyer.

               (xv) "Person" means any living person or any entity, such as, but
not necessarily limited to, a corporation, partnership or trust.

               (xvi) "Affiliate" means, with respect to a specific Person
referred to in the relevant provision, another Person who or which controls or
is controlled by or is under common control with such specified Person.

               (xvii) "Transaction Documents means the Securities Purchase
Agreement, the Registration Rights Agreement, the Warrant, and the Certificate
of Designations.

               c. FORM OF PAYMENT; DELIVERY OF CERTIFICATES.

               (i) The Buyer shall pay the Purchase Price for the relevant
Preferred Stock by delivering immediately available good funds in United States
Dollars to the escrow agent (the "Escrow Agent") identified in the Joint Escrow
Instructions attached hereto as Annex II (the "Joint Escrow Instructions") on
the date prior to the relevant Closing Date.

               (ii) No later than the relevant Closing Date, but in any event
promptly following payment by the Buyer to the Escrow Agent of the relevant
Purchase Price, the Company shall deliver the relevant Certificates to the
Escrow Agent.

               (iii) By signing this Agreement, each of the Buyer and the
Company, subject to acceptance by the Escrow Agent, agrees to all of the terms
and conditions of, and becomes a party to, the Joint Escrow Instructions, all of
the provisions of which are incorporated herein by this reference as if set
forth in full.

               d. METHOD OF PAYMENT. Payment into escrow of the Purchase Price
shall be made by wire transfer of funds to:

                      Bank of New York
                      350 Fifth Avenue
                      New York, New York 10001

                      ABA# 021000018
                      For credit to the account of Krieger & Prager, Esqs.
                      Account No.: [To be provided by Krieger & Prager]
                      Re: ESAT, Inc.

Not later than 5:00 p.m., New York time, on the date which is seven (7) New York
Stock Exchange trading days after the Company shall have accepted this Agreement
and returned a signed counterpart of this Agreement to the Escrow Agent by
facsimile, the Buyer shall deposit



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with the Escrow Agent the Purchase Price for the Preferred Stock in currently
available funds. Time is of the essence with respect to such payment, and
failure by the Buyer to make such payment, shall allow the Company to cancel
this Agreement.

               e. ESCROW PROPERTY. The Purchase Price and the Certificates
delivered to the Escrow Agent as contemplated by Sections 1(c) and (d) hereof
are referred to as the "Escrow Property."

               2. BUYER REPRESENTATIONS, WARRANTIES, ETC.; ACCESS TO
INFORMATION; INDEPENDENT INVESTIGATION.

               The Buyer represents and warrants to, and covenants and agrees
with, the Company as follows:

               a. Without limiting Buyer's right to sell the Common Stock
pursuant to the Registration Statement, the Buyer is purchasing the Preferred
Stock and the Warrants and will be acquiring the Shares for its own account for
investment only and not with a view towards the public sale or distribution
thereof and not with a view to or for sale in connection with any distribution
thereof.

               b. The Buyer is (i) an "accredited investor" as that term is
defined in Rule 501 of the General Rules and Regulations under the 1933 Act by
reason of Rule 501(a)(3), (ii) experienced in making investments of the kind
described in this Agreement and the related documents, (iii) able, by reason of
the business and financial experience of its officers (if an entity) and
professional advisors (who are not affiliated with or compensated in any way by
the Company or any of its affiliates or selling agents), to protect its own
interests in connection with the transactions described in this Agreement, and
the related documents, and (iv) able to afford the entire loss of its investment
in the Securities.

               c. All subsequent offers and sales of the Preferred Stock and the
Shares by the Buyer shall be made pursuant to registration of the Shares under
the 1933 Act or pursuant to an exemption from registration.

               d. The Buyer understands that the Preferred Stock is being
offered and sold to it in reliance on specific exemptions from the registration
requirements of United States federal and state securities laws and that the
Company is relying upon the truth and accuracy of, and the Buyer's compliance
with, the representations, warranties, agreements, acknowledgments and
understandings of the Buyer set forth herein in order to determine the
availability of such exemptions and the eligibility of the Buyer to acquire the
Preferred Stock.

               e. The Buyer and its advisors, if any, have been furnished with
or have been given access to all materials relating to the business, finances
and operations of the Company and materials relating to the offer and sale of
the Preferred Stock and the offer of the Shares which have been requested by the
Buyer, including ANNEX V hereto. The Buyer and its advisors, if any, have been
afforded the opportunity to ask questions of the Company and have received
complete



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and satisfactory answers to any such inquiries. Without limiting the
generality of the foregoing, the Buyer has also had the opportunity to obtain
and to review the Company's Form 10-SB Registration Statement (the "Company's
SEC Documents").

               f. The Buyer understands that its investment in the Securities
involves a high degree of risk.

               g. The Buyer understands that no United States federal or state
agency or any other government or governmental agency has passed on or made any
recommendation or endorsement of the Securities.

               h. This Agreement has been duly and validly authorized, executed
and delivered on behalf of the Buyer and is a valid and binding agreement of the
Buyer enforceable in accordance with its terms, subject as to enforceability to
general principles of equity and to bankruptcy, insolvency, moratorium and other
similar laws affecting the enforcement of creditors' rights generally.

               i. The Buyer is a corporation duly organized, validly existing
and in good standing under the laws of the Cayman Islands and has the requisite
corporate power to own its properties and to carry on its business as now being
conducted. The Buyer is duly qualified as a foreign corporation to do business
and is in good standing in each jurisdiction where the nature of the business
conducted or property owned by it makes such qualification necessary, other than
those jurisdictions in which the failure to so qualify would not have a material
adverse effect on the business, operations or condition (financial or otherwise)
or results of operations of the Company and its subsidiaries taken as a whole.

               j. Buyer is a "sophisticated investor" (as described in Rule
506(b)(2)(ii) of Regulation D) and an "accredited investor" (as defined in Rule
501(a) of Regulation D), and Purchaser has such knowledge and experience in
business and financial matters that it is capable of evaluating the merits and
risks of an investment in the Company's securities.

               k. The Buyer expressly agrees that that until all of the
Preferred Stock shall have been converted, the Buyer shall not engage in short
sales of the Common Stock of the Company. The Buyer acknowledges that purchases,
sales and other transactions may be subject to various federal and state
securities laws and agrees to comply with all such applicable securities laws.

               3. COMPANY REPRESENTATIONS, ETC. The Company represents and
warrants to the Buyer that, except as provided in ANNEX V hereto:

               a. CONCERNING THE PREFERRED STOCK AND THE SHARES. There are no
preemptive rights of any stockholder of the Company, as such, to acquire the
Preferred Stock, the Warrants or the Shares.



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               b. REPORTING COMPANY STATUS. The Company is a corporation duly
organized, validly existing and in good standing under the laws of the State of
Delaware and has the requisite corporate power to own its properties and to
carry on its business as now being conducted. The Company is duly qualified as a
foreign corporation to do business and is in good standing in each jurisdiction
where the nature of the business conducted or property owned by it makes such
qualification necessary, other than those jurisdictions in which the failure to
so qualify would not have a material adverse effect on the business, operations
or condition (financial or otherwise) or results of operation of the Company and
its subsidiaries taken as a whole. The Company has filed a Form 10-SB to
register its Common Stock pursuant to Section 12 of the 1934 Act, and the Common
Stock is listed and traded on The NASDAQ/Bulletin Board Market. The Company has
received no notice, either oral or written, with respect to the continued
eligibility of the Common Stock for such listing, and the Company has maintained
all requirements for the continuation of such listing.

               c. AUTHORIZED SHARES. The authorized capital stock of the Company
consists of (i) 50,000,00 shares of Common Stock, $.001 par value per share, of
which approximately 18,191,062 had been issued as of December 20, 1999 and
(ii) 10,000,000 shares of Preferred Stock with rights, preferences and
limitations to be determined by the Board of Directors of the Company, of which
the Series A and Series B have been authorized for a total of 2,000,000 shares.
As of the date of this Agreement, there are no shares of Preferred Stock issued.
All issued and outstanding shares of Common Stock have been duly authorized and
validly issued and are fully paid and nonassessable. The Company has sufficient
authorized and unissued shares of Common Stock as may be necessary to effect the
issuance of the Shares. The Shares have been duly authorized and, when issued
upon conversion of, or as interest on, the Preferred Stock or upon exercise of
the Warrants, each in accordance with its respective terms, will be duly and
validly issued, fully paid and non- assessable and will not subject the holder
thereof to personal liability by reason of being such holder.

               d. SECURITIES PURCHASE AGREEMENT; REGISTRATION RIGHTS AGREEMENT
AND STOCK. This Agreement and the Registration Rights Agreement, the form of
which is attached hereto as ANNEX IV (the "Registration Rights Agreement"), and
the transactions contemplated thereby, have been duly and validly authorized by
the Company, this Agreement has been duly executed and delivered by the Company
and this Agreement is, and the Preferred Stock, the Warrants and the
Registration Rights Agreement, when executed and delivered by the Company, will
be, valid and binding agreements of the Company enforceable in accordance with
their respective terms, subject as to enforceability to general principles of
equity and to bankruptcy, insolvency, moratorium, and other similar laws
affecting the enforcement of creditors' rights generally.

               e. NON-CONTRAVENTION. The execution and delivery of this
Agreement and the Registration Rights Agreement by the Company, the issuance of
the Securities, and the consummation by the Company of the other transactions
contemplated by this Agreement, the Registration Rights Agreement, and the
Preferred Stock do not and will not conflict with or result in a breach by the
Company of any of the terms or provisions of, or constitute a default



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under (i) the articles of incorporation or by-laws of the Company, each as
currently in effect, (ii) any indenture, mortgage, deed of trust, or other
material agreement or instrument to which the Company is a party or by which it
or any of its properties or assets are bound, including any listing agreement
for the Common Stock except as herein set forth, (iii) to its knowledge, any
existing applicable law, rule, or regulation or any applicable decree, judgment,
or order of any court, United States federal or state regulatory body,
administrative agency, or other governmental body having jurisdiction over the
Company or any of its properties or assets, or (iv) the Company's listing
agreement for its Common Stock, except such conflict, breach or default which
would not have a material adverse effect on the business, operations or
condition (financial or otherwise) or results of operations of the Company and
its subsidiaries, taken as a whole, or on the transactions contemplated herein.

               f. APPROVALS. No authorization, approval or consent of any court,
governmental body, regulatory agency, self-regulatory organization, or stock
exchange or market or the stockholders of the Company is required to be obtained
by the Company for the issuance and sale of the Securities to the Buyer as
contemplated by this Agreement, except such authorizations, approvals and
consents that have been obtained.

               g. SEC FILINGS. None of the Company's SEC Documents contained, at
the time they were filed, any untrue statement of a material fact or omitted to
state any material fact required to be stated therein or necessary to make the
statements made therein in light of the circumstances under which they were
made, not misleading. The Company has since November 1, 1999 timely filed all
requisite forms, reports and exhibits thereto with the SEC.

               h. ABSENCE OF CERTAIN CHANGES. Since December 31, 1998, there has
been no material adverse change and no material adverse development in the
business, properties, operations, condition (financial or otherwise), or results
of operations of the Company, except as disclosed in the Company's SEC
Documents. Since December 31, 1998, except as provided in the Company's SEC
Documents, the Company has not (i) incurred or become subject to any material
liabilities (absolute or contingent) except liabilities incurred in the ordinary
course of business consistent with past practices; (ii) discharged or satisfied
any material lien or encumbrance or paid any material obligation or liability
(absolute or contingent), other than current liabilities paid in the ordinary
course of business consistent with past practices; (iii) declared or made any
payment or distribution of cash or other property to stockholders with respect
to its capital stock, or purchased or redeemed, or made any agreements to
purchase or redeem, any shares of its capital stock; (iv) sold, assigned or
transferred any other tangible assets, or canceled any debts or claims, except
in the ordinary course of business consistent with past practices; (v) suffered
any substantial losses or waived any rights of material value, whether or not in
the ordinary course of business, or suffered the loss of any material amount of
existing business; (vi) made any changes in employee compensation, except in the
ordinary course of business consistent with past practices; or (vii) experienced
any material problems with labor or management in connection with the terms and
conditions of their employment.

               i. FULL DISCLOSURE. There is no fact known to the Company (other
than



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general economic conditions known to the public generally or as disclosed in the
Company's SEC Documents) that has not been disclosed in writing to the Buyer
that (i) would reasonably be expected to have a material adverse effect on the
business or condition of the Company (financial or otherwise) or results of
operations of the Company and its subsidiaries, taken as a whole , (ii) would
reasonably be expected to materially and adversely affect the ability of the
Company to perform its obligations pursuant to this Agreement or any of the
agreements contemplated hereby (collectively, including this Agreement, the
"Transaction Agreements"), or (iii) would reasonably be expected to materially
and adversely affect the value of the rights granted to the Buyer in the
Transaction Agreements.

               j. ABSENCE OF LITIGATION. Except as set forth in the Company's
SEC Documents, there is no action, suit, proceeding, inquiry or investigation
before or by any court, public board or body pending or, to the knowledge of the
Company, threatened against or affecting the Company, wherein an unfavorable
decision, ruling or finding would have a material adverse effect on the
properties, business or financial condition, or results of operation of the
Company and its subsidiaries taken as a whole or the transactions contemplated
by any of the Transaction Agreements or which would adversely affect the
validity or enforceability of, or the authority or ability of the Company to
perform its obligations under, any of the Transaction Agreements.

               k. ABSENCE OF EVENTS OF DEFAULT. Except as set forth in Section
3(e) hereof, no Event of Default (or its equivalent term), as defined in the
respective agreement to which the Company is a party, and no event which, with
the giving of notice or the passage of time or both, would become an Event of
Default (or its equivalent term) (as so defined in such agreement), has occurred
and is continuing, which would have a material adverse effect on the business,
operations or the condition (financial or otherwise) or results of operations of
the Company and its subsidiaries, taken as a whole.

               l. PRIOR ISSUES. During the twelve (12) months preceding the date
hereof, the Company has not issued any convertible securities or, except as
provided in the Company's SEC Documents, any shares of the Common Stock or
Preferred Stock.

               m. NO UNDISCLOSED LIABILITIES OR EVENTS. The Company has no
liabilities or obligations other than those disclosed in the Company's SEC
Documents or those incurred in the ordinary course of the Company's business
since December 31, 1998, and which individually or in the aggregate, do not or
would not have a material adverse effect on the properties, business, condition
(financial or otherwise), or results of operations of the Company and its
subsidiaries, taken as a whole. No event or circumstances has occurred or exists
with respect to the Company or its properties, business, condition (financial or
otherwise), or results of operations, which, under applicable law, rule or
regulation, requires public disclosure or announcement prior to the date hereof
by the Company but which has not been so publicly announced or disclosed. Except
for mergers or acquisitions requiring the issuance of common stock and/or
preferred stock, there are no proposals currently under consideration or
currently anticipated to be under consideration by the Board of Directors or the
executive officers of the Company which proposal would (x)



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change the certificate of incorporation or other charter document or by-laws of
the Company, each as currently in effect, with or without shareholder approval,
which change would reduce or otherwise adversely affect the rights and powers of
the shareholders of the Common Stock or (y) materially or substantially change
the business, assets or capital of the Company, including its interests in
subsidiaries.

               n. NO DEFAULT. The Company is not in default in the performance
or observance of any material obligation, agreement, covenant or condition
contained in any material indenture, mortgage, deed of trust or other material
instrument or agreement to which it is a party or by which it or its property is
bound.

               o. NO INTEGRATED OFFERING. Neither the Company nor any of its
affiliates nor any person acting on its or their behalf has, directly or
indirectly, at any time since November 1, 1999, made any offer or sales of any
security or solicited any offers to buy any security under circumstances that
would eliminate the availability of the exemption from registration under Rule
506 of Regulation D in connection with the offer and sale of the Securities as
contemplated hereby.

               p. DILUTION. The number of Shares issuable upon conversion of the
Preferred Stock and the exercise of the Warrants may increase substantially in
certain circumstances, including, but not necessarily limited to, the
circumstance wherein the trading price of the Common Stock declines prior to the
conversion of the Preferred Stock. The Company's executive officers and
directors have studied and fully understand the nature of the Securities being
sold hereby and recognize that they have a potential dilutive effect. The board
of directors of the Company has concluded, in its good faith business judgment,
that such issuance is in the best interests of the Company. The Company
specifically acknowledges that its obligation to issue the Shares upon
conversion of the Preferred Stock and upon exercise of the Warrants is binding
upon the Company and enforceable regardless of the dilution such issuance may
have on the ownership interests of other shareholders of the Company.

               4. CERTAIN COVENANTS AND ACKNOWLEDGMENTS.

               a. TRANSFER RESTRICTIONS. The Buyer acknowledges that (1) the
Preferred Stock have not been and are not being registered under the provisions
of the 1933 Act and, except as provided in the Registration Rights Agreement,
the Shares have not been and are not being registered under the 1933 Act, and
may not be transferred unless (A) subsequently registered thereunder or (B) the
Buyer shall have delivered to the Company an opinion of counsel, reasonably
satisfactory in form, scope and substance to the Company, to the effect that the
Securities to be sold or transferred may be sold or transferred pursuant to an
exemption from such registration; (2) any sale of the Securities made in
reliance on Rule 144 promulgated under the 1933 Act may be made only in
accordance with the terms of said Rule and further, if said Rule is not
applicable, any resale of such Securities under circumstances in which the
seller, or the person through whom the sale is made, may be deemed to be an
underwriter, as that term is used in the 1933 Act, may require compliance with
some other exemption under the 1933 Act or



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the rules and regulations of the SEC thereunder; and (3) neither the Company nor
any other person is under any obligation to register the Securities (other than
pursuant to the Registration Rights Agreement) under the 1933 Act or to comply
with the terms and conditions of any exemption thereunder.

               b. RESTRICTIVE LEGEND. The Buyer acknowledges and agrees that the
Preferred Stock and the Warrants, and, until such time as the Common Stock has
been registered under the 1933 Act as contemplated by the Registration Rights
Agreement and sold in accordance with an effective Registration Statement,
certificates and other instruments representing any of the Securities shall bear
a restrictive legend in substantially the following form (and a stop-transfer
order may be placed against transfer of any such Securities):

               THESE SECURITIES (THE "SECURITIES") HAVE NOT BEEN REGISTERED
UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR THE
SECURITIES LAWS OF ANY STATE AND MAY NOT BE SOLD OR OFFERED FOR SALE IN THE
ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT FOR THE SECURITIES OR AN OPINION
OF COUNSEL OR OTHER EVIDENCE ACCEPTABLE TO THE CORPORATION THAT SUCH
REGISTRATION IS NOT REQUIRED.

               c. REGISTRATION RIGHTS AGREEMENT. The parties hereto agree to
enter into the Registration Rights Agreement on or before the Closing Date.

               d. FILINGS. The Company undertakes and agrees to make all
necessary filings in connection with the sale of the Securities to the Buyer
under any United States laws and regulations applicable to the Company, or by
any domestic securities exchange or trading market, and to provide a copy
thereof to the Buyer promptly after such filing.

               e. REPORTING STATUS. So long as the Buyer beneficially owns any
of the Securities, the Company shall file all reports required to be filed with
the SEC pursuant to Section 13 or 15(d) of the 1934 Act, and the Company shall
not terminate its status as an issuer required to file reports under the 1934
Act even if the 1934 Act or the rules and regulations thereunder would permit
such termination. The Company will take all reasonable action under its control
to obtain and to continue the listing and trading of its Common Stock
(including, without limitation, all Registrable Securities) on The
NASDAQ/Bulletin Board Market and will comply in all material respects with the
Company's reporting, filing and other obligations under the by-laws or rules of
the National Association of Securities Dealers, Inc. ("NASD") or The
NASDAQ/Bulletin Board Market.

               f. USE OF PROCEEDS. The Buyer acknowledges that the Company
intends to make acquisitions or effect mergers subsequent to the execution of
this Agreement. Accordingly, the Company will use the proceeds from the sale of
the Preferred Stock (excluding amounts paid by the Company for legal fees,
finder's fees and escrow fees in connection with the sale of the Preferred
Stock) for cash deposits associated with such acquisitions or mergers and for



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internal working capital purposes. Except for the express purposes detailed in
this section 4f, unless specifically consented to in advance in each instance by
the Buyer, the Company shall not, directly or indirectly, use such proceeds for
any loan to or investment in any other corporation, partnership enterprise or
other person or for the repayment of any outstanding loan by the Company to any
other party.

               g. CERTAIN AGREEMENTS. (i) The Company covenants and agrees that
it will not, without the prior written consent of the Buyer, enter into any
subsequent or further offer or sale of Common Stock or securities convertible
into Common Stock (collectively, "New Common Stock") with any third party
pursuant to a transaction which in any manner permits the sale of the New Common
Stock on any date which is earlier than one hundred twenty (120) days from the
last day of the calendar month in which the Effective Date occurs.

               (ii) The provisions of subparagraph (g)(i) will not apply to (w)
Common Stock issued pursuant to an exemption from registration under the
Securities Act of 1933 other than pursuant to Regulation S; (x) an underwritten
public offering of shares of Common Stock or Preferred Stock; (y) an offering of
convertible Preferred Stock at market or above; or (z) the issuance of
securities (other than for cash) in connection with an acquisition, merger,
consolidation, sale of assets, disposition or the exchange of the capital stock
for assets, stock or other joint venture interests.

               (iii) By the Closing Date, the Company shall obtain the agreement
(each, a "Principal's Agreement") of each of its Principals (as defined below)
that, without the prior written consent of the Buyer in each instance, such
Principal will not sell or otherwise transfer or offer to sell or otherwise
transfer any shares of Common Stock directly or indirectly held by such
Principal prior to one hundred twenty (120) days after the Effective Date. Each
such Principal's Agreement shall (w) specify that it is entered into as an
inducement to the Buyer's execution, delivery and performance of this Agreement,
(x) name the Buyer as a third party beneficiary thereof, (y) acknowledge that
the Company's transfer agent will be provided with instructions that transfers
by a Principal require the consent of the Company and the Buyer, and (z)
contemplate that, in addition to any other damages or remedies that may be
appropriate, the Principal's Agreement shall be enforceable by injunction sought
by the Company and the Buyer or any one or more of them. A "Corporate Principal"
is a person who meets any one or more of the following criteria: (A) a person
who is a director or principal officer of the Company (each, a "Company
Principal") and who, directly or indirectly, holds in excess of five (5%)
percent of any shares of Common Stock of the Company (each, a "Company
Principal"); (B) a spouse of a Company Principal (a "Principal's Spouse") who,
directly or indirectly, holds any shares of Common Stock of the Company, (C) a
parent or child of a Company Principal who resides in the household of a Company
Principal or of a Principal's Spouse (each, a "Principal's Relative") and who,
directly or indirectly, holds any shares of Common Stock, or (D) any other
person or entity, including, without limitation, for profit or non-profit
corporations, partnerships and trusts, whose voting rights regarding Common
Stock of the Company is subject to the direction, control or other influence of
any Company Principal, Principal's Spouse, or Principal's Relative.

               (iv) In the event the Company breaches the provisions of this
Section 4(g), the



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Conversion Rate (as defined in the Certificate of Designations) shall be amended
to be equal to (x) 90% of (y) the amount determined in accordance with the
provisions of the Preferred Stock without regard to this provision, and the
Purchaser may require the Company to immediately redeem all outstanding
Preferred Stock in accordance with Section 4(j)(y) hereof.

               h. AVAILABLE SHARES. The Company shall have at all times
authorized and reserved for issuance, free from preemptive rights, shares of
Common Stock sufficient to yield two hundred percent (200%) of the number of
shares of Common Stock issuable (i) at conversion as may be required to satisfy
the conversion rights of the Buyer pursuant to the terms and conditions of the
Preferred Stock which have been issued and not yet converted, and (ii) upon
exercise as may be required to satisfy the exercise rights of the Buyer pursuant
to the terms and conditions of the Warrants which have been issued and not yet
converted.

               i. WARRANTS. The Company agrees to issue to the Buyer on each
Closing Date transferable, divisible warrants with cashless exercise rights (the
"Warrants") for the purchase of one (1) share of Common Stock for every 6.66
shares into which the Preferred Stock purchased by the Buyer are convertible
into on the Closing Date. Fractional shares shall be rounded up to the next
highest share. The Warrants shall bear an exercise price equal to one hundred
twenty-five percent (125%) of the Market Price of the Common Stock on the
relevant Closing Date. The Warrants will expire on the last day of the month in
which the fifth anniversary of the relevant Closing Date occurs. The Warrants
shall be in the form annexed hereto as ANNEX VI, together with registration
rights as provided in the Registration Rights Agreement and piggy-back
registration after the expiration of the effectiveness of the Registration
Statement contemplated by the Registration Rights Agreement.

               j. LIMITATION ON ISSUANCE OF SHARES. The Company may be limited
in the number of shares of Common Stock it may issue by virtue of (i) the number
of authorized shares or (ii) the applicable rules and regulations of the
principal securities market on which the Common Stock is listed or traded,
including, but not necessarily limited to, NASDAQ Rule 4310(c)(25)(H)(i)(d)(2)
(collectively, the "Cap Regulations"). Without limiting the other provisions
thereof, the Certificate of Designations shall provide that (i) the Company will
take all steps reasonably necessary to be in a position to issue shares of
Common Stock on conversion of the Preferred Stock without violating the Cap
Regulations and (ii) if, despite taking such steps, the Company still can not
issue such shares of Common Stock without violating the Cap Regulations, the
holder of a Preferred Stock which can not be converted as result of the Cap
Regulations (each such Preferred Stock, an "Unconverted Preferred Stock") shall
have the option, exercisable in such holder's sole and absolute discretion, to
elect either of the following remedies:

                      (x) if permitted by the Cap Regulations, require the
        Company to issue (x) shares of Common Stock in accordance with such
        holder's notice of conversion at a conversion purchase price equal to
        the average of the closing bid price per share of Common Stock for any
        five (5) consecutive trading days (subject to certain equitable
        adjustments for certain events occurring during such period) during the
        sixty (60) trading days immediately preceding the date of



                                       12
<PAGE>   13

        notice of conversion; or

                      (y) require the Company to redeem each Unconverted
        Preferred Stock (y) for an amount (the "Redemption Amount") as set forth
        in the Certificate of Designations.

A holder of an Unconverted Preferred Stock may elect one of the above remedies
with respect to a portion of such Unconverted Preferred Stock and the other
remedy with respect to other portions of the Unconverted Preferred Stock. The
Certificate of Designations shall contain provisions substantially consistent
with the above terms, with such additional provisions as may be consented to by
the Buyer. The provisions of this paragraph are not intended to limit the scope
of the provisions otherwise included in the Certificate of Designations.

               k. RIGHT OF FIRST REFUSAL, SPECIAL DILUTION PROTECTION.

               (i) The Company covenants and agrees that if during the period
from the date hereof through and including the date which is thirty (30) days
after the first closing of the purchase of Common Stock pursuant to the Letter
of Intent dated December 27, 1999 between the Company and the Buyer, the Company
offers to enters into any transaction (a "New Transaction") for the sale of New
Common Stock, the Company shall notify the Buyer in writing of all of the terms
of such offer (a "New Transaction Offer"). The Buyer shall have the right (the
"Right of First Refusal"), exercisable by written notice given to the Company by
the close of business on the fifth business day after the Buyer's receipt of the
New Transaction Offer (the "Right of First Refusal Expiration Date"), to
participate in all or any part of the New Transaction Offer on the terms so
specified.

               (ii) If, and only if, the Buyer does not exercise the Right of
First Refusal in full, the Company may consummate the remaining portion of the
New Transaction with any New Investor on the terms specified in the New
Transaction Offer within thirty (30) days of the Right of First Refusal
Expiration Date.

               (iii) If the terms of the New Transaction to be consummated with
such other party differ from the terms specified in the New Transaction Offer so
that the terms are more beneficial in any respect to the New Investor, the
Company shall give the Buyer a New Transaction Offer relating to the terms of
the New Transaction, as so changed, and the Buyer's Right of First Refusal and
the preceding terms of this paragraph (l) shall apply with respect to such
changed terms.

               (iv) If there is more than one Buyer signatory to this Agreement,
the preceding provisions of this paragraph (l) shall apply pro rata among them
(based on their relative Buyer's Allocable Shares), except that, to the extent
any such Buyer does not exercise its Right of First Refusal in full (a
"Declining Buyer"), the remaining Buyer or Buyers who or which have exercised
their own Right of First Refusal in full, shall have the right (pro rata among
them based



                                       13
<PAGE>   14

on their relative Buyer's Allocable Shares, if more than one) to exercise all or
a portion of such Declining Buyer's unexercised Right of Refusal. Nothing in
this paragraph (l) shall be deemed to permit a transaction not otherwise
permitted by subparagraph (g)(i), as modified by the provisions of subparagraph
(g)(ii).

               (v) In the event the New Transaction is consummated with such
other third party on terms providing for (x) either a sale price equal to or
computed based on, or a determination of a conversion price based on, a lower
percentage of the then current market price (howsoever defined or computed) than
provided in the Certificate of Designations for determining the Conversion Rate
or a lower Base Price (howsoever defined or computed) and/or (y) the issuance of
warrants at an exercise price lower than that provided in the Warrants, the
terms of any unissued or unconverted Preferred Stock or any unissued or
unexercised Warrants shall be modified to reduce the relevant Conversion Rate,
Base Price or Warrant exercise price to be equal to that provided in the New
Transaction as so consummated.

               l. REIMBURSEMENT. If (i) any Buyer, other than by reason of its
gross negligence or willful misconduct, becomes involved in any capacity in any
action, proceeding or investigation brought by any stockholder of the Company,
in connection with or as a result of the consummation of the transactions
contemplated by the Transaction Agreements, or if such Buyer is impleaded in any
such action, proceeding or investigation by any Person, or (ii) any Buyer, other
than by reason of its gross negligence or willful misconduct or by reason of its
trading of the Common Stock in a manner that is illegal under the federal
securities laws, becomes involved in any capacity in any action, proceeding or
investigation brought by the SEC against or involving the Company or in
connection with or as a result of the consummation of the transactions
contemplated by the Transaction Agreements, or if such Buyer is impleaded in any
such action, proceeding or investigation by any Person, then in any such case,
the Company will reimburse such Buyer for its reasonable legal and other
expenses (including the cost of any investigation and preparation) incurred in
connection therewith, as such expenses are incurred. In addition, other than
with respect to any matter in which such Buyer is a named party, the Company
will pay such Buyer the charges, as reasonably determined by such Buyer, for the
time of any officers or employees of such Buyer devoted to appearing and
preparing to appear as witnesses, assisting in preparation for hearings, trials
or pretrial matters, or otherwise with respect to inquiries, hearing, trials,
and other proceedings relating to the subject matter of this Agreement. The
reimbursement obligations of the Company under this paragraph shall be in
addition to any liability which the Company may otherwise have, shall extend
upon the same terms and conditions to any Affiliates of the Buyers who are
actually named in such action, proceeding or investigation, and partners,
directors, agents, employees and controlling persons (if any), as the case may
be, of the Buyers and any such Affiliate, and shall be binding upon and inure to
the benefit of any successors, assigns, heirs and personal representatives of
the Company, the Buyers and any such Affiliate and any such Person. The Company
also agrees that neither any Buyer nor any such Affiliate, partners, directors,
agents, employees or controlling persons shall have any liability to the Company
or any person asserting claims on behalf of or in right of the Company in
connection with or as a result of the consummation of the Transaction Agreements
except to the extent that any losses, claims, damages, liabilities or



                                       14
<PAGE>   15

expenses incurred by the Company result from the gross negligence or willful
misconduct of such Buyer.

               5. TRANSFER AGENT INSTRUCTIONS.

               a. Promptly following the delivery by the Buyer of the Purchase
Price for the Preferred Stock in accordance with Section 1(c) hereof, the
Company will irrevocably instruct its transfer agent to issue Common Stock from
time to time upon conversion of the Preferred Stock in such amounts as specified
from time to time by the Company to the transfer agent, bearing the restrictive
legend specified in Section 4(b) of this Agreement prior to registration of the
Shares under the 1933 Act, registered in the name of the Buyer or its nominee
and in such denominations to be specified by the Buyer in connection with each
conversion of the Preferred Stock. The Company warrants that no instruction
other than such instructions referred to in this Section 5 and stop transfer
instructions to give effect to Section 4(a) hereof prior to registration and
sale of the Shares under the 1933 Act will be given by the Company to the
transfer agent and that the Shares shall otherwise be freely transferable on the
books and records of the Company as and to the extent provided in this
Agreement, the Registration Rights Agreement, and applicable law. Nothing in
this Section shall affect in any way the Buyer's obligations and agreement to
comply with all applicable securities laws upon resale of the Securities. If the
Buyer provides the Company with an opinion of counsel reasonably satisfactory to
the Company that registration of a resale by the Buyer of any of the Securities
in accordance with clause (1)(B) of Section 4(a) of this Agreement is not
required under the 1933 Act, the Company shall (except as provided in clause (2)
of Section 4(a) of this Agreement) permit the transfer of the Securities and, in
the case of the Converted Shares or the Warrant Shares, as the case may be,
promptly instruct the Company's transfer agent to issue one or more certificates
for Common Stock without legend in such name and in such denominations as
specified by the Buyer.

               b. (i) The Company will permit the Buyer to exercise its right to
convert the Preferred Stock by telecopying or delivering an executed and
completed Notice of Conversion to the Company and delivering, within five (5)
business days thereafter, the original Preferred Stock being converted to the
Company by express courier, with a copy to the transfer agent.

                  (ii) The term "Conversion Date" means, with respect to any
conversion elected by the holder of the Preferred Stock, the date specified in
the Notice of Conversion, provided the copy of the Notice of Conversion is
telecopied to or otherwise delivered to the Company in accordance with the
provisions hereof so that it is received by the Company on or before such
specified date.

                  (iii) The Company will transmit the certificates
representing the Converted Shares issuable upon conversion of any Preferred
Stock (together, unless otherwise instructed by the Buyer, with Preferred Stock
not being so converted) to the Buyer at the address specified in the Notice of
Conversion (which may be the Buyer's address for notices as contemplated by
Section 11 hereof or a different address) via express courier , by electronic
transfer or otherwise, within three (3) business days if the address for
delivery is in the United



                                       15
<PAGE>   16

States and within five (5) business days if the address for delivery is outside
the United States (such fifth business day or seventh business day, as the case
may be, the "Delivery Date") after (A) the business day on which the Company has
received both of the Notice of Conversion (by facsimile or other delivery) and
the original Preferred Stock being converted (and if the same are not delivered
to the Company on the same date, the date of delivery of the second of such
items) or (B) the date an interest payment on the Preferred Stock, which the
Company has elected to pay by the issuance of Common Stock, as contemplated by
the Preferred Stock, was due.

               c. The Company understands that a delay in the issuance of the
Shares of Common Stock beyond the Delivery Date could result in economic loss to
the Buyer. As compensation to the Buyer for such loss, the Company agrees to pay
late payments to the Buyer for late issuance of Shares upon Conversion in
accordance with the Certificate of Designations.

               d. In lieu of delivering physical certificates representing the
Common Stock issuable upon conversion, provided the Company's transfer agent is
participating in the Depository Trust Company ("DTC") Fast Automated Securities
Transfer program, upon request of the Buyer and its compliance with the
provisions contained in this paragraph, so long as the certificates therefor do
not bear a legend and the Buyer thereof is not obligated to return such
certificate for the placement of a legend thereon, the Company shall use its
best efforts to cause its transfer agent to electronically transmit the Common
Stock issuable upon conversion to the Buyer by crediting the account of Buyer's
Prime Broker with DTC through its Deposit Withdrawal Agent Commission system.

               e. The Company will authorize its transfer agent to give
information relating to the Company directly to the Buyer or the Buyer's
representatives upon the request of the Buyer or any such representative. The
Company will provide the Buyer with a copy of the authorization so given to the
transfer agent.

               f. The Company will authorize its transfer agent to give
information relating to the Company directly to the Buyer or the Buyer's
representatives upon the request of the Buyer or any such representative. The
Company will provide the Buyer with a copy of the authorization so given to the
transfer agent.

               g. If, at any time (i) the Company challenges, disputes or denies
the right of a holder of Preferred Stock to effect a conversion of the Preferred
Stock into Common Stock or otherwise dishonors or rejects any Conversion Notice
delivered in accordance with the terms of this Agreement or the Certificate of
Designations or any exercise of any Warrant in accordance with its terms
("Warrant Exercise"), or (ii) any third party who is not and has never been an
Affiliate of such holder commences any lawsuit or proceeding or otherwise
asserts any claim before any court or public or governmental authority, which
lawsuit, proceeding or claim seeks to challenge, deny, enjoin, limit, modify,
delay or dispute the right of such holder to effect the conversion of the
Preferred Stock into Common Stock, and the Company refuses to honor any such
Conversion Notice or Warrant Exercise, then such holder shall have the right, by
written



                                       16
<PAGE>   17

notice to the Company, to require the Company to promptly redeem the Preferred
Stock for cash at a redemption price (the "Mandatory Purchase Amount") equal to
(x) one hundred twenty-two percent (122%) of the liquidation preference of the
unconverted Preferred Stock held by such holder plus (y) all accrued but unpaid
dividends on the Preferred Stock through the date of payment of the Mandatory
Purchase Amount. Under any of the circumstances set forth above, the Company
shall be responsible for the payment of all costs and expenses of such holder,
including, but not necessarily limited to, reasonable legal fees and expenses,
as and when incurred in connection with such holder's disputing any such action
or pursuing such holder's rights hereunder (in addition to any other rights such
holder may have hereunder or otherwise). The Mandatory Purchase Amount will be
payable to such holder in cash within five (5) business days from the date such
holder gives the Company written notice that it is exercising its rights under
this paragraph.

               h. The holder of any Preferred Stock shall be entitled to
exercise its conversion privilege with respect to the Preferred Stock
notwithstanding the commencement of any case under 11 U.S.C.Section 101 et seq.
(the "Bankruptcy Code"). In the event the Company is a debtor under the
Bankruptcy Code, the Company hereby waives, to the fullest extent permitted, any
rights to relief it may have under 11 U.S.C.Section 362 in respect of such
holder's conversion privilege. The Company hereby waives, to the fullest extent
permitted, any rights to relief it may have under 11 U.S.C. Section 362 in
respect of the conversion of the Preferred Stock. The Company agrees, without
cost or expense to such holder, to take or to consent to any and all action
necessary to effectuate relief under 11 U.S.C. Section 362.

               6. CLOSING DATES.

               a. The Closing Date shall occur on the date which is the first
NYSE trading day after each of the conditions contemplated by Sections 7 and 8
hereof shall have either been satisfied or been waived by the party in whose
favor such conditions run.

               b. The closing of the purchase and issuance of Preferred Stock
shall occur on the relevant Closing Date at the offices of the Escrow Agent and
shall take place no later than 3:00 P.M., New York time, on such day or such
other time as is mutually agreed upon by the Company and the Buyer.

               c. Notwithstanding anything to the contrary contained herein, the
Escrow Agent will be authorized to release the Escrow Funds to the Company and
to others and to release the other Escrow Property on the relevant Closing Date
upon satisfaction of the conditions set forth in Sections 7 and 8 hereof and as
provided in the Joint Escrow Instructions.

               7. CONDITIONS TO THE COMPANY'S OBLIGATION TO SELL.

               The Buyer understands that the Company's obligation to sell the
relevant Preferred Stock to the Buyer pursuant to this Agreement on the relevant
Closing Date is conditioned upon:



                                       17
<PAGE>   18

               a. The execution and delivery of this Agreement by the Buyer;

               b. Delivery by the Buyer to the Escrow Agent of good funds as
payment in full of an amount equal to the Purchase Price for the relevant
Preferred Stock in accordance with this Agreement;

               c. The accuracy on such Closing Date of the representations and
warranties of the Buyer contained in this Agreement, each as if made on such
date, and the performance by the Buyer on or before such date of all covenants
and agreements of the Buyer required to be performed on or before such date; and

               d. There shall not be in effect any law, rule or regulation
prohibiting or restricting the transactions contemplated hereby, or requiring
any consent or approval which shall not have been obtained.

               8. CONDITIONS TO THE BUYER'S OBLIGATION TO PURCHASE.

               The Company understands that the Buyer's obligation to purchase
the Preferred Stock on the relevant Closing Date is conditioned upon:

               a. The execution and delivery of this Agreement and the
Registration Rights Agreement by the Company;

               b. Delivery by the Company to the Escrow Agent of the relevant
Certificates in accordance with this Agreement;

               c. The accuracy in all material respects on such Closing Date of
the representations and warranties of the Company contained in this Agreement.
each as if made on such date, and the performance by the Company on or before
such date of all covenants and agreements of the Company required to be
performed on or before such date;

               d. On such Closing Date, the Registration Rights Agreement shall
be in full force and effect and the Company shall not be in default thereunder;

               e. On such Closing Date, the Buyer shall have received an opinion
of counsel for the Company, dated such Closing Date, in form, scope and
substance reasonably satisfactory to the Buyer, substantially to the effect set
forth in ANNEX III attached hereto;

               f. There shall not be in effect any law, rule or regulation
prohibiting or restricting the transactions contemplated hereby, or requiring
any consent or approval which



                                       18
<PAGE>   19

shall not have been obtained;

               g. From and after the date hereof to and including such Closing
Date, the trading of the Common Stock shall not have been suspended by the SEC
or the NASD and trading in securities generally on the New York Stock Exchange
or The NASDAQ/Bulletin Board Market shall not have been suspended or limited,
nor shall minimum prices been established for securities traded on The
NASDAQ/Bulletin Board Market, nor shall there be any outbreak or escalation of
hostilities involving the United States or any material adverse change in any
financial market that in either case in the reasonable judgment of the Buyer
makes it impracticable or inadvisable to purchase the Preferred Stock; and

               9. GOVERNING LAW: MISCELLANEOUS.

               a. This Agreement shall be governed by and interpreted in
accordance with the laws of the State of California for contracts to be wholly
performed in such state and without giving effect to the principles thereof
regarding the conflict of laws. Each of the parties consents to the jurisdiction
of the federal courts whose districts encompass any part of the City of Los
Angeles or the state courts of the State of California sitting in the City of
Los Angeles in connection with any dispute arising under this Agreement and
hereby waives, to the maximum extent permitted by law, any objection, including
any objection based on forum non conveniens, to the bringing of any such
proceeding in such jurisdictions. To the extent determined by such court, the
Company shall reimburse the Buyer for any reasonable legal fees and
disbursements incurred by the Buyer in enforcement of or protection of any of
its rights under any of the Transaction Agreements.

               b. Failure of any party to exercise any right or remedy under
this Agreement or otherwise, or delay by a party in exercising such right or
remedy, shall not operate as a waiver thereof.

               c. This Agreement shall inure to the benefit of and be binding
upon the successors and assigns of each of the parties hereto.

               d. All pronouns and any variations thereof refer to the
masculine, feminine or neuter, singular or plural, as the context may require.

               e. A facsimile transmission of this signed Agreement shall be
legal and binding on all parties hereto.

               f. This Agreement may be signed in one or more counterparts, each
of which shall be deemed an original.

               g. The headings of this Agreement are for convenience of
reference and shall not form part of, or affect the interpretation of, this
Agreement.



                                       19
<PAGE>   20

               h. If any provision of this Agreement shall be invalid or
unenforceable in any jurisdiction, such invalidity or unenforceability shall not
affect the validity or enforceability of the remainder of this Agreement or the
validity or enforceability of this Agreement in any other jurisdiction.

               i. This Agreement may be amended only by an instrument in writing
signed by the party to be charged with enforcement thereof.

               j. This Agreement supersedes all prior agreements and
understandings among the parties hereto with respect to the subject matter
hereof.

               10. NOTICES. Any notice required or permitted hereunder shall be
given in writing (unless otherwise specified herein) and shall be deemed
effectively given on the earliest of

               (a) the date delivered, if delivered by personal delivery as
               against written receipt therefor or by confirmed facsimile
               transmission,

               (b) the seventh business day after deposit, postage prepaid, in
               the United States Postal Service by registered or certified mail,
               or

               (c) the third business day after mailing by international express
               courier, with delivery costs and fees prepaid,

in each case, addressed to each of the other parties thereunto entitled at the
following addresses (or at such other addresses as such party may designate by
ten (10) days' advance written notice similarly given to each of the other
parties hereto):

COMPANY:              ESAT, Inc.
                      16520 Harbor Boulevard, Bldg. G
                      Fountain Valley, California 92708
                      Telephone No.: (714) 418-3200
                      Telecopier No.:

with a copy to:       Arter & Hadden LLP
                      725 South Figueroa Street, Suite 3400
                      Los Angeles, California 90017
                      Attn:   Kay Rustand, Esq.
                      Telephone No.: (213) 430-3000
                      Telecopier No.: (213) 617-9255

BUYER:                At the address set forth on the signature page of this
                      Agreement.

with a copy to:       Krieger & Prager, Esqs.



                                       20
<PAGE>   21

                      Suite 1440
                      39 Broadway
                      New York, New York 10006
                      Attn: Samuel Krieger, Esq.
                      Telephone No.: (212) 363-2900
                      Telecopier No.  (212) 363-2999

ESCROW AGENT:         Krieger & Prager, Esqs.
                      Suite 1440
                      39 Broadway
                      New York, New York 10006
                      Attn: Samuel Krieger, Esq.
                      Telephone No.: (212) 363-2900
                      Telecopier No.  (212) 363-2999

               11. SURVIVAL OF REPRESENTATIONS AND WARRANTIES. The Company's and
the Buyer's representations and warranties herein shall survive the execution
and delivery of this Agreement and the delivery of the Certificates and the
Warrants and the payment of the Purchase Price, and shall inure to the benefit
of the Buyer and the Company and their respective successors and assigns.

                  [BALANCE OF PAGE INTENTIONALLY LEFT BLANK.]

               IN WITNESS WHEREOF, this Agreement has been duly executed by the
Buyer by one of its officers thereunto duly authorized as of the date set forth
below.

AMOUNT AND PURCHASE PRICE OF PREFERRED STOCK:                 $5,000,000


                            SIGNATURES FOR ENTITIES


        IN WITNESS WHEREOF, the undersigned represents that the foregoing
statements are true and correct and that it has caused this Securities Purchase
Agreement to be duly executed on its behalf this 23rd day of December, 1999.


Corporate Centre, West Bay Road              WENTWORTH LLC
-----------------------------------          -----------------------------------
Address                                      Printed Name of Subscriber
Grand Cayman
-----------------------------------
                                             By: /s/
                                             -----------------------------------
Telecopier No.  (284) 494-4771                  Navigator Management Ltd.
                                                Director
Cayman Islands                               Printed Name and Title
-----------------------------------
Jurisdiction of Incorporation
or Organization



                                       21
<PAGE>   22

As of the date set forth below, the undersigned hereby accepts this Agreement
and represents that the foregoing statements are true and correct and that it
has caused this Securities Purchase Agreement to be duly executed on its behalf.

ESAT, INC.

By:    /s/
       -----------------------------------
       Michael C. Palmer
Title: Chief Executive Officer & Secretary
Date:  December 29, 1999



                                       22
<PAGE>   23

        ANNEX I              FORM OF PREFERRED STOCK

        ANNEX II             JOINT ESCROW INSTRUCTIONS

        ANNEX III            OPINION OF COUNSEL

        ANNEX IV             REGISTRATION RIGHTS AGREEMENT

        ANNEX V              COMPANY DISCLOSURE MATERIALS

        ANNEX VI             FORM OF WARRANT



                                       23
<PAGE>   24

                                                                         ANNEX V
                                                                              TO
                                                   SECURITIES PURCHASE AGREEMENT



                                                        COMPANY DISCLOSURE




                                      NONE



                                       24