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                                                                   Exhibit 10.4

                                  CAMBIO, INC.

            SERIES B CONVERTIBLE PREFERRED STOCK PURCHASE AGREEMENT

         AGREEMENT, dated as of the 1st day of February, 1999, by and among
CAMBIO, INC., a Delaware corporation (the "Company"), and each of the entities
severally listed on the Schedule of Purchasers attached hereto (collectively,
the "Purchasers" and individually, a "Purchaser").

         WHEREAS, the Company desires to issue and sell, and the Purchasers
desire to purchase, certain securities of the Company.

         NOW, THEREFORE, in consideration of the premises and mutual covenants
and conditions herein contained, the parties hereto agree as follows:


                                   SECTION 1

                      Authorization and Sale of the Shares

                  1.1 Authorization of the Shares. The Company has, or before
the first Subsequent Closing to occur pursuant to this Agreement will have,
authorized the sale and issuance of up to 100,000 shares of its Series B
Convertible Preferred Stock, par value $.01 per share (the "Preferred Stock"),
having the rights, restrictions, privileges and preferences set forth in the
Certificate of the Designations, Powers, Preferences and Rights of the Series B
Convertible Preferred Stock (par value $.01 per share) to the Restated
Certificate of Incorporation of the Company (the "Certificate of Designations")
attached to this Agreement as Exhibit A. The shares of Preferred Stock being
sold to the Purchasers hereunder are referred to herein collectively as the
"Shares" and individually as a "Share." As used herein, at and as of the
Closing, the term Certificate of Incorporation shall include the Restated
Certificate of Incorporation, as amended to date (including any previously
filed certificates of designation, as amended), and the Certificate of
Designations. Unless otherwise agreed to by the Purchasers, any Closing
occurring prior to the filing of the Company's Certificate of Designations,
shall be deemed to have occurred immediately subsequent to the filing of the
Certificate of Designations.

                  1.2 Sale of the Shares. Subject to the terms and conditions
hereof and in reliance upon the representations, warranties and agreements
contained herein, the Company will issue and sell to each of the Purchasers,
severally and not jointly, and each of the Purchasers will purchase from the
Company, the number of shares of Preferred Stock set forth opposite such
Purchaser's name on the Schedule of Purchasers attached hereto (the "Schedule
of Purchasers") under the column labeled "Shares of Series B Preferred Stock,"
at the aggregate purchase price set forth opposite such Purchaser's name on the
Schedule of Purchasers under the column heading "Total Investment."


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                                   SECTION 2

                                  Closing Date

                  2.1 Initial Closing Date. The first closing of the purchase
and sale of the Shares hereunder (the "Initial Closing") shall be held shortly
following the execution and delivery of this Agreement on February 3, 1999 (the
"Initial Closing Date") at a time and place determined pursuant to Section 2.3
hereof.

                  2.2 Delivery. At the Initial Closing or as soon as
practicable thereafter, the Company shall deliver to each Purchaser
certificates in such denominations and registered in such names as set forth in
the Schedule of Purchasers attached hereto, representing the number of shares
of Preferred Stock to be purchased by such Purchaser from the Company, against
payment at the Initial Closing, by certified or bank check, or wire transfer,
of the amount set forth opposite such Purchaser's name in the column labeled
"Total Investment" on the Schedule of Purchasers.

                  2.3 Place of Initial Closing. The Initial Closing (including
the delivery to the Purchasers by the Company of the certificates evidencing
all Shares being purchased and the place of payment to the Company (except in
the case of a wire transfer) by the Purchasers of the purchase price therefor)
shall take place at 10 a.m., New York time, at the offices of Fulbright &
Jaworski L.L.P., 666 Fifth Avenue, New York, New York 10103 or at such other
time and place as shall be mutually agreed upon by the parties.

                  2.4 Subsequent Closings. At any time, on or after February 3,
1999, upon the mutual agreement of the Company and any additional prospective
investors (the "Subsequent Closing Purchasers"), the Company may conduct
additional closings (the "Subsequent Closings") of the purchase and sale of
Preferred Stock ("Subsequent Closing Securities"), provided that the aggregate
purchase price of the Shares sold at the Initial Closing and the Subsequent
Closings does not exceed $6 million. The Subsequent Closings shall take place
at the offices of Fulbright & Jaworski L.L.P., 666 Fifth Avenue, New York, New
York 10103 at 10:00 a.m., New York time, or at such other locations as may be
agreed upon among the Subsequent Closing Purchasers purchasing Subsequent
Closing Securities at such closings and the Company (such dates and times being
called the "Subsequent Closing Dates"). At the Subsequent Closings, or as soon
as practicable thereafter, the Company shall issue and deliver to each
Subsequent Closing Purchaser a stock certificate or certificates in definitive
form, registered in the name of such Subsequent Closing Purchaser, representing
the Shares being purchased by it at such Subsequent Closings. On each of the
Subsequent Closing Dates this Agreement shall be amended by adding the name and
address of each such Subsequent Closing Purchaser to the Schedule of Purchasers
attached hereto, along with the number of Shares purchased and the aggregate
purchase price to be paid by each Subsequent Closing Purchaser, and as payment
in full for the Shares being purchased by it at each Subsequent Closing, and
against delivery of the stock certificates therefor as aforesaid, each
Subsequent Closing Purchaser shall deliver to the Company a certified or bank
check in the amount set forth opposite


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the name of such Purchaser in the column labeled "Total Investment" on the
Schedule of Purchasers, as so amended, or shall transfer such sum to the
account of the Company by wire transfer. Following such amendment to this
Agreement, each Subsequent Purchaser at each Subsequent Closing shall be deemed
a Purchaser for all purposes hereunder and all such Subsequent Closing
Securities shall be deemed Shares.

                  2.5 Closing Date. As used in this Agreement, the term
"Closing" shall mean, as applicable, the Initial Closing or any Subsequent
Closing, and the term "Closing Date" shall mean, as applicable, the Initial
Closing Date or any Subsequent Closing Date.

                                   SECTION 3

                       Representations and Warranties of
                                  the Company

                  Except as set forth in the "Schedule of Exceptions" delivered
to each Purchaser prior to the execution hereof and attached hereto, the
Company hereby represents and warrants to each Purchaser that, as of the date
hereof:

                  3.1 Organization and Standing; Articles and By-Laws. The
Company is a corporation duly organized and validly existing and in good
standing under the laws of the State of Delaware and is qualified to do
business in each jurisdiction in which the character of its properties or the
nature of its business requires such qualification, except where the failure to
so qualify would not have a material adverse effect upon the business,
operations or prospects of the Company. The Company has the requisite corporate
power to own the properties owned by it and to conduct business as now being
conducted by it and possesses all governmental and other permits, licenses and
other authorizations to own its properties as now owned and to conduct its
business as now conducted.

                  3.2 Corporate Power. The Company has all requisite corporate
power to enter into this Agreement, and has or will have at the first
Subsequent Closing all requisite corporate power to sell the Shares and to
carry out and perform its obligations under the terms of this Agreement, except
for the filing of an amendment to the Company's Certificate of Incorporation to
increase the authorized number of Class A Common Stock.

                  3.3 Authorization. All corporate action on the part of the
Company, its directors and stockholders necessary for the authorization,
execution, delivery and performance by the Company of this Agreement and the
consummation of the transactions contemplated herein, and for the
authorization, issuance and delivery of the Shares has been taken or will be
taken prior to the first Subsequent Closing, except for the filing of an
amendment to the Company's Certificate of Incorporation to increase the
authorized number of Class A Common Stock. This Agreement is a valid and
binding obligation of the Company, enforceable in accordance with its terms,
subject to applicable bankruptcy, insolvency, reorganization and moratorium
laws and other laws of general


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application affecting enforcement of creditors' rights generally and to general
equitable principles. The execution, delivery and performance by the Company of
this Agreement and compliance herewith and the issuance and sale of the Shares
and the issuance of Common Stock issuable upon conversion of the Shares will
not (a) result in any violation of and will not conflict with, or result in a
breach of any of the terms of, or constitute a default under, the Company's
Certificate of Incorporation or By-Laws, as amended, any mortgage, indenture,
agreement, instrument, judgment, decree, order, rule or regulation or other
restriction to which the Company is a party or by which it is bound or any
provision of state or Federal law to which the Company is subject, or (b)
result in the creation of any mortgage, pledge, lien, encumbrance or charge
upon any of the properties or assets of the Company pursuant to any such term,
or (c) result in the suspension, revocation, impairment, forfeiture or
non-renewal of any permit, license, authorization or approval applicable to the
Company's operations or any of its assets or properties. The Shares, when
issued in compliance with the provisions of this Agreement, will be validly
issued, fully paid and nonassessable; will be free of any liens or
encumbrances; and will have the rights, privileges and preferences as set forth
in the Certificate of Designations. Upon the filing of an amendment to the
Company's Certificate of Incorporation to increase the authorized number of
Class A Common Stock, the shares of Common Stock issuable upon conversion of
the Shares will be duly and validly reserved and will not be subject to any
preemptive rights or rights of first refusal and, upon issuance, will be
validly issued, fully paid and nonassessable.

                  3.4 Capitalization. The Company has 15,000,000 authorized
shares of the Company's Class A Common Stock, par value $.01 per share (the
"Common Stock"), 5,000,000 authorized shares of the Company's Class B Common
Stock, par value $.01 per share (the "Class B Common Stock") and 1,000,000
authorized shares of Preferred Stock. As of the date hereof: (i) 3,832,411
shares of Common Stock are issued and outstanding; (ii) no shares of the Class
B Common Stock are issued and outstanding; (iii) options to purchase 5,645,603
shares of Common Stock have been authorized; and (iv) no shares of Preferred
Stock are issued and outstanding. Except for warrant to be issued in connection
with the transactions contemplated by this Agreement (the "Warrant"), there are
no other shares outstanding or issuable under existing warrants or options.

                  3.5 Litigation. There is neither pending nor, to the
Company's knowledge and belief, threatened any action, suit, proceeding or
claim, or any basis therefor or threat thereof, whether or not purportedly on
behalf of the Company, to which the Company is or may be named as a party or to
which its property is or may be subject or to the Company's knowledge, after
due inquiry, to which any director or officer of the Company (in his or her
capacity as such) is subject, and in which an unfavorable outcome, ruling or
finding in any such matter or for all such matters taken as a whole might
reasonably have a material adverse effect on the condition, financial or
otherwise, prospects, operations or results of operations of the Company.

                  3.6 Absence of Undisclosed Liabilities. The Company does not
have any debts, liabilities or obligations of any nature arising out of
transactions entered into prior to the date hereof except for (i) liabilities
specifically provided for in the consolidated financial statements of the
Company and the notes thereto contained in the Company's Quarterly Report on
Form 10-QSB for


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the quarter ended December 31, 1998 and (ii) for liabilities and obligations
arising out of the ordinary course of business, consistent in form and amount
with past practice, since December 31, 1998.

                  3.7 SEC Reports. The Company has filed all required forms,
reports and documents with the Securities and Exchange Commission (the "SEC")
since January 1, 1997 (collectively, the "SEC Reports" and, individually, an
"SEC Report"), all of which SEC Reports have complied in all material respects
with all applicable requirements of the Securities Act of 1933, as amended (the
"Securities Act"), and the Securities Exchange Act of 1934, as amended (the
"Exchange Act").

                  3.8 Absence of Certain Changes. Except as set forth or
otherwise reflected in an SEC Report, since December 31, 1998, the Company has
conducted its business only in the ordinary and usual course and there has not
occurred (i) any material adverse change in the business, financial condition,
operations, results of operations or prospects of the Company or (ii) any
change by the Company in accounting principles or methods, except insofar as
may be required by a change in generally accepted accounting principles.

                  3.9 Taxes. The Company has filed all tax returns that are
required to have been filed for, by, on behalf of or with regard to the Company
and its business and such returns are true, correct, and complete and reflect
all liabilities for taxes for the periods covered thereby. The Company has paid
in full all taxes, interest and penalties, if any, reflected on such tax
returns or otherwise due and payable by it.


                                   SECTION 4

                  Representations and Warranties of Purchasers

                  Each Purchaser, severally and not jointly, represents and
warrants with respect to such Purchaser to the Company as follows:

                  4.1 Experience; Accredited Investor Status. (a) Such
Purchaser is experienced in evaluating and investing in companies such as the
Company. Such Purchaser has such knowledge and experience in financing and
business matters that such Purchaser is capable of evaluating the merits and
risks of an investment in the Shares and of making an informed decision.

                      (b) Such Purchaser is an "accredited investor," as such
term is defined in Rule 501(a) promulgated under the Securities Act of 1933, as
amended (the "Securities Act").

                  4.2 Investment. Such Purchaser is acquiring the Shares for
investment for such Purchaser's own account and not with the view to, or for
resale in connection with, any distribution thereof. Such Purchaser understands
that the Shares are being issued to such Purchaser, and the



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shares of Common Stock issuable upon conversion of the Shares are to be issued
to such Purchaser, (i) without registration under the Securities Act by reason
of a specified exemption from the registration provisions of the Securities Act
which depends upon, among other things, the bona fide nature of such
Purchaser's investment intent as expressed herein, and (ii) without
qualification under applicable state securities laws.

                  4.3 Rule 144. Such Purchaser acknowledges that the Shares and
the shares of Common Stock issuable upon conversion of the Shares must be held
indefinitely unless they are subsequently registered under the Securities Act
and qualified under applicable state securities laws or exemptions from such
registration and qualification are available. Such Purchaser is familiar with
Rule 144 promulgated under the Securities Act and understands the resale
limitations imposed thereby.

                  4.4 Access to Data. Such Purchaser has had an opportunity to
discuss the Company's business, management and financial affairs with its
management and has had the opportunity to review the Company's books, records
and facilities.

                  4.5 Access to SEC Reports. Such Purchaser has received and
carefully reviewed (i) the Company's Quarterly Report on Form 10-QSB for the
quarters ended September 30, 1998 and December 31, 1998 and (ii) all other
information filed by the Company pursuant to the Securities Act or the
Securities Exchange Act of 1934, as amended. Such Purchaser has reviewed the
section in the Company's Quarterly Reports on Form 10-QSB entitled "Other
Factors That May Affect Future Operating Results" and is aware of the risks
affecting the Company specified therein.

                  4.6 Restrictions on Transfers. Such Purchaser understands and
agrees as follows:

                  (a) The certificates evidencing the Preferred Stock (and, to
the extent not otherwise registered, the Common Stock issuable upon conversion
thereof), and each certificate issued in transfer of the foregoing, will bear
the following legends (or substantially similar legends):

                  (i)      "THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE
                           SECURITIES ACT OF 1933, AS AMENDED, OR QUALIFIED
                           UNDER ANY STATE SECURITIES LAWS. THE SECURITIES MAY
                           NOT BE OFFERED, SOLD, TRANSFERRED OR OTHERWISE
                           DISPOSED OF WITHOUT SUCH REGISTRATION AND
                           QUALIFICATION OR THE DELIVERY TO THE COMPANY OF AN
                           OPINION OF COUNSEL, REASONABLY SATISFACTORY TO THE
                           COMPANY, THAT SUCH DISPOSITION WILL NOT REQUIRE
                           REGISTRATION OF SUCH SECURITIES UNDER THE SECURITIES
                           ACT OF 1933, AS AMENDED, OR ANY APPLICABLE STATE
                           SECURITIES LAWS"; and

                  (ii)     any legend required by applicable state securities
                           laws.


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                  (b) Such Purchaser will not offer, sell, transfer or
otherwise dispose of any of the Preferred Stock, or any Common Stock issuable
upon conversion thereof, unless (i) an effective registration under the
Securities Act (and an effective qualification under applicable state
securities laws, or exemption therefrom) covers the disposition of such
securities, or (ii) such Purchaser has delivered to the Company an opinion of
counsel, reasonably satisfactory to the Company, that such offer, sale,
transfer or other disposition will not require registration of such securities
under the Securities Act or qualification under any applicable state securities
laws.

                  4.7 Authorization. All corporate or partnership action, as
the case may be, on the part of such Purchaser, and its directors and
stockholders or partners, as applicable, necessary for the authorization,
execution, delivery and performance by such Purchaser of this Agreement and the
consummation of the transactions contemplated herein, has been taken or will be
taken prior to the Closing. This Agreement is a valid and binding obligation of
such Purchaser, enforceable in accordance with its terms, subject to applicable
bankruptcy, insolvency, reorganization and moratorium laws and other laws of
general application affecting enforcement of creditors' rights generally and to
general equitable principles. The execution, delivery and performance by such
Purchaser of this Agreement and compliance herewith will not result in any
violation of and will not conflict with, or result in a breach of any of the
terms of, or constitute a default under, such Purchaser's Certificate of
Incorporation or By-Laws or Agreement of Limited Partnership, as applicable.

                  4.8 Principal Place of Business; Place of Negotiations. Such
Purchaser's principal place of business is at the location set forth on the
Schedule of Purchasers. This Agreement was negotiated only in the state of New
York. The Company's offer of Shares to such Purchaser, and such Purchaser's
acceptance of the Company's offer, occurred in the State of New York, unless
otherwise indicated under such Purchaser's name in the Schedule of Exceptions.


                                   SECTION 5

                      Conditions to Closing of Purchasers

                  The obligation of each Purchaser to purchase the Shares to be
purchased at the Closing is subject to the fulfillment to such Purchaser's
reasonable satisfaction on or prior to the Closing Date of each of the
following conditions:

                  5.1 Representations and Warranties Correct. The
representations and warranties made by the Company in Section 3 hereof shall be
true and correct in all material respects when made, and shall be true and
correct in all material respects on the Closing Date with the same force and
effect as if they had been made on and as of the Closing Date.

                  5.2 Legal Investment. At the time of the Closing, the
purchase of the Shares to be purchased by the Purchasers hereunder shall be
legally permitted by all laws and regulations to which the Purchasers and the
Company are subject.



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                  5.3 Performance. All covenants, agreements and conditions
contained in this Agreement to be performed or complied with by the Company on
or prior to the Closing Date shall have been performed or complied with in all
material respects.

                                   SECTION 6

                        Conditions to Closing of Company

                  The Company's obligation to sell the Shares to be purchased
at the Closing is subject to the fulfillment to its satisfaction on or prior to
the Closing Date of each of the following conditions:

                  6.1 Representations. The representations made by each of the
Purchasers pursuant to Section 4 hereof shall be true and correct in all
material respects when made and shall be true and correct in all material
respects on the Closing Date.

                  6.2 Legal Investment. At the time of the Closing, the
purchase of the Shares to be purchased by the Purchasers hereunder shall be
legally permitted by all laws and regulations to which the Purchasers and the
Company are subject.

                                   SECTION 7

                           Registration of Securities

                  7.1 Certain Definitions. As used in this Section 7, the
following terms shall have the following respective meanings:

                  "Registrable Securities" shall mean, collectively, the shares
of Common Stock issuable upon conversion of the Shares, the exercise of the
Warrant and upon any stock split, stock dividend, recapitalization or similar
event relating thereto.

                  The terms "register," "registered" and "registration" shall
refer to a registration effected by preparing and filing a registration
statement in compliance with the Securities Act and applicable rules and
regulations thereunder, and the declaration or ordering of the effectiveness of
such registration statement.

                  "Registration Expenses" shall mean all expenses incurred by
the Company in compliance with Sections 7.2 and 7.4 hereof, including, without
limitation, all registration and filing fees, printing expenses, fees and
disbursements of counsel for the Company, blue sky fees and expenses, and the
expense of any special audits incident to or required by any such registration
(but excluding the compensation of regular employees of the Company, which
shall be paid in any event by the Company).



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                  "SEC" shall mean the U.S. Securities and Exchange Commission.

                  "Selling Expenses" shall mean all underwriting discounts and
selling commissions, if any, applicable to the sale of securities and all fees
and disbursements of counsel for any Holder (as hereinafter defined).

                  "Holder" shall mean any holder of Registrable Securities
which have not been sold to the public.

                  7.2 Mandatory Registration. The Company shall use its best
efforts to prepare and file with the SEC a registration statement (the
"Registration Statement") for the registration under the Securities Act of all
of the Registrable Securities within 90 days after the first Subsequent
Closing. The Company shall use its best efforts to cause such Registration
Statement to become effective as soon as practicable, and to remain effective
and current until the earlier of (i) the redemption by the Company of all the
Preferred Stock and (ii) the sale of all the Registrable Securities (the
"Effective Period"); but in no event later than the earlier to occur of (i)
three years after the conversion of all Shares of Preferred Stock or (ii)
December 31, 2004. If the Registration Statement covering the Registrable
Securities is not declared effective by the SEC by the 180th day after the
first Subsequent Closing and there is a delay for up to 30 additional days (a
"30 Day Delay"), then the base price for computing the Conversion Price (as
defined in the Certificate of Designations) shall be reduced from $0.20 per
share to $0.16 per share; and if the Registration Statement covering the
Registrable Securities is not declared effective by the SEC by the 180th day
after the final Closing and there is a delay for up to between 31 and 60
additional days (a "60 Day Delay"), then such base price shall be reduced from
$0.16 per share to $0.12 per share.

                  7.3 Expenses of Registration. The Company shall bear all
Registration Expenses incurred in connection with any registration,
qualification or compliance pursuant to this Agreement. All Selling Expenses
shall be borne by the Holders pro rata on the basis of the number of their
shares so registered, or, in the case of fees and disbursements of
Holders' counsel, in such proportions and amounts as the Holders shall mutually
agree.

                  7.4 Registration Procedures. The Company will keep each
Holder advised in writing as to the initiation of the registration and as to
the completion thereof. At its expense, as long as the Company is required to
use its best efforts to keep the Registration Statement effective pursuant to
Section 7.2 hereof, the Company will:

                      (a) Prepare and file with the SEC such amendments and
supplements to the Registration Statement and the prospectus used in connection
with such Registration Statement as may be necessary to comply with Section 7.2
hereof and with the provisions of the Securities Act with respect to the
disposition of securities covered by such Registration Statement;



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                      (b) Furnish such number of prospectuses and other
documents incident thereto, including any amendments of or supplements to the
prospectus, as a Holder from time to time may reasonably request;

                      (c) Notify each seller of Registrable Securities covered
by the Registration Statement at any time when a prospectus relating thereto is
required to be delivered under the Securities Act of the happening of any event
as a result of which the prospectus included in such Registration Statement, as
then in effect, includes an untrue statement of a material fact or omits to
state a material fact required to be stated therein or necessary to make the
statements therein not misleading or incomplete in the light of the
circumstances then existing, and at the request of any such seller, prepare and
furnish to such seller a reasonable number of copies of a supplement to or an
amendment of such prospectus as may be necessary so that, as thereafter
delivered to the purchaser of such shares, such prospectus shall not include an
untrue statement of a material fact or omit to state a material fact required
to be stated therein or necessary to make the statements therein not misleading
or incomplete in the light of the circumstances then existing;

                      (d) Cause all such Registrable Securities to be listed on
each securities exchange on which similar securities issued by the Company are
then listed, as set forth in Section 7.9 hereof;

                      (e) Make available for inspection by any seller of
Registrable Securities, any underwriter participating in any disposition
pursuant to the Registration Statement, and any attorney or accountant retained
by any such seller or underwriter, all financial and other records, pertinent
corporate documents and properties of the Company, and cause the Company's
officers and directors to supply all information reasonably requested by any
such seller, underwriter, attorney or accountant in connection with such
Registration Statement: provided, however, that such seller, underwriter,
attorney or accountant shall agree to hold in confidence and trust all
information so provided;

                      (f) Furnish to each selling Holder upon request a copy of
all documents filed with and all correspondence from or to the SEC in
connection with any such offering other than non-substantive cover letters and
the like;

                      (g) Otherwise use its best efforts to comply with all
applicable rules and regulations of the SEC, and make generally available to
its security holders, an earnings statement covering a period of at least
twelve months beginning after the effective date of the Registration Statement,
which earnings statement shall satisfy the provisions of Section 11(a) of the
Securities Act. Such statement may be provided to the Company's security
holders through the first annual report mailed to such security holders which
includes financial statements for the appropriate period; provided, however,
that if any Shares are converted into Common Stock prior to the date such
earnings statement is made generally available to the Company's security
holders, the Company shall make such statement generally available as soon as
practicable; and



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                      (h) Use its best efforts to register or qualify the
Registrable Securities under the securities or blue sky laws of each
jurisdiction as any Holder shall reasonably request, to keep such registration
or qualification in effect for so long as the Registration Statement remains in
effect, and do any and all other acts or things which may be necessary or
advisable to enable such Holder to consummate the public sale or other
disposition in such jurisdictions of the Registrable Securities: provided,
however, that the Company shall not be required to consent to general service
of process in any jurisdiction where it is not then qualified or subject itself
to the payment of any taxes or the jurisdiction of any taxing authority where
the Company would not otherwise be subject.

                  7.5 Indemnification. (a) To the extent permitted by
applicable law, the Company will indemnify each Holder, each of their
respective officers, directors and partners, and each person controlling such
Holder, and each underwriter, if any, and each person who controls any
underwriter, against all claims, losses, damages and liabilities (or actions,
proceedings or settlements in respect thereof) arising out of or based on any
untrue statement (or alleged untrue statement) of a material fact contained in
any prospectus, offering circular or other document (including any related
registration statement, notification or the like) incident to any registration,
qualification or compliance required pursuant to this Section 7, or based on
any omission (or alleged omission) to state therein a material fact required to
be stated therein or necessary to make the statements therein not misleading,
or any violation by the Company of the Securities Act or any rule or regulation
thereunder applicable to the Company and relating to action or inaction
required of the Company in connection with any such registration, qualification
or compliance, and will reimburse each such Holder, each of their respective
officers, directors and partners, and each person controlling such Holder, each
such underwriter, if any, and each person who controls any such underwriter,
for any legal and any other expenses as are reasonably incurred in connection
with investigating and defending any such claim, loss, damage, liability or
action, provided that the Company will not be liable in any such case to the
extent that any such claim, loss, damage, liability or expense arises out of or
is based on any untrue statement or omission based upon written information
furnished to the Company by any person to be indemnified hereunder and stated
to be specifically for use therein.

                      (b) To the extent permitted by applicable law, each Holder
will, if securities held by it are included in the securities as to which such
registration, qualification or compliance is being effected, indemnify the
Company, each of its directors and officers and each underwriter, if any, of
the Company's securities covered by such other Registration Statement, and each
person who controls the Company or such underwriter within the meaning of the
Securities Act and the rules and regulations thereunder, each other Holder, and
each of their officers, directors and partners, and each person controlling
such other Holder, against all claims, losses, damages and liabilities (or
actions, proceedings or settlements in respect thereof) arising out of or based
on any untrue statement (or alleged untrue statement) of a material fact
contained in any prospectus, offering circular or other document (including any
related registration statement, notification or the like) incident to any
registration, qualification, or compliance required pursuant to this Section 7,
or based on any omission (or alleged omission) to state therein a material fact
required to be stated therein or necessary to make the statements therein not
misleading, and will reimburse the Company and such other Holders, directors,
officers, partners, underwriters, if any, or control persons for any legal or



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any other expenses reasonably incurred in connection with investigating or
defending any such claim, loss, damage, liability or action, in each case to
the extent, but only to the extent, that such untrue statement (or alleged
untrue statement) or omission (or alleged omission) is made in such
registration statement, prospectus, offering circular or other document in
reliance upon and in conformity with written information furnished to the
Company by such Holder and stated to be specifically for use therein: provided,
however, that the obligations of any such Holder hereunder shall be limited to
an amount equal to the proceeds to such Holder of securities sold under such
registration statement, prospectus, offering circular or other document as
contemplated herein.

                      (c) Each party entitled to indemnification under this
Section 7.5 (the "Indemnified Party") shall give notice to the party required
to provide indemnification (the "Indemnifying Party") promptly after such
Indemnified Party has actual knowledge of any claim as to which indemnity may
be sought, and shall permit the Indemnifying Party to assume the defense of any
such claim or any litigation resulting therefrom, provided that counsel for the
Indemnifying Party, who shall conduct the defense of such claim or any
litigation resulting therefrom, shall be approved by the Indemnified Party
(whose approval shall not unreasonably be withheld), and the Indemnified Party
may participate in such defense at such party's expense; and provided further
that the failure of any Indemnified Party to give notice as provided herein
shall not relieve the Indemnifying Party of its obligations under this Section
7.5 unless such failure to notify shall be materially prejudicial to the
Indemnifying Party's ability to defend such action. No Indemnifying Party, in
the defense of any such claim or litigation, shall, except with the consent of
each Indemnified Party (which consent shall not be unreasonably withheld),
consent to entry of any judgment or enter into any settlement which does not
include as an unconditional term thereof the giving by the claimant or
plaintiff to such Indemnified Party of a release from all liability in respect
to such claim or litigation. Each Indemnified Party shall furnish such
information regarding itself or the claim in question as an Indemnifying Party
may reasonably request in writing and as shall be reasonably required in
connection with the defense of such claim and litigation resulting therefrom.
No Indemnified Party shall, except with the consent of each Indemnifying Party
(which consent shall not be unreasonably withheld), consent to entry of any
judgment or enter into any settlement.

                  7.6 Information by Holder. Each Holder of Registrable
Securities shall furnish to the Company such information regarding such Holder
as the Company may reasonably request in writing and as shall be reasonably
required in connection with any registration, qualification or compliance
referred to in this Agreement. If requested by the Company, the Holder will
specifically state that such information is to be used in a prospectus,
offering circular or other document (including any related registration
statement, notification or the like) incident to any registration,
qualification or compliance required pursuant to this Section 7.

                  7.7 Limitations on Registration of Issues of Securities. From
and after the date of this Agreement until the Registration Statement has been
declared effective, the Company shall not enter into any agreement with any
holder or prospective holder of any securities of the Company giving such
holder or prospective holder a right to require the Company to register
securities owned by such holder, other than as contemplated by this Agreement.



                                      12
<PAGE>   13

                  7.8 Rule 144 Reporting. With a view to making available the
benefits of certain rules and regulations of the SEC which may permit the sale
of the Registrable Securities to the public without registration, the Company
shall until the tenth anniversary of the final Closing agree to:

                  (a) Use its best efforts to make and keep public information
available as those terms are understood and defined in Rule 144 under the
Securities Act at all times after the final Closing;

                  (b) Use its best efforts to file with the SEC in a timely
manner all reports and other documents required of the Company under the
Securities Act and the Exchange Act; and

                  (c) So long as a Holder owns any Registrable Securities,
furnish to the Holder forthwith upon request a written statement by the Company
as to its compliance with the reporting requirements of Rule 144 and of the
Securities Act and the Exchange Act and such other reports and documents so
filed as the Holder may reasonably request in availing itself of any rule or
regulation of the SEC allowing the Holder to sell any such securities without
registration.

                  7.9 OTC Listing. Prior to the registration of all of the
Registrable Securities pursuant to this Section 7, (i) all applications,
filings and documents necessary to list on the OTC Bulletin Board (the "OTC")
the Registrable Securities shall have been filed and, where applicable,
approved, and (ii) all such Registrable Securities shall have been listed (or
approved for listing subject to issuance) on the OTC.

                  7.10 Additional OTC Listing. Upon the happening of any event
pursuant to which additional shares of Common Stock not otherwise included in
the Registrable Securities shall become issuable upon conversion of the
Preferred Stock, the Company will file all applications, filings and documents
necessary to list, and will use its best efforts to cause the listing of all
such additional shares of Common Stock on the OTC (or such other national
securities exchange on which the Common Stock is then being traded). Such
additional shares of Common Stock shall, upon their listing, be classified as
and included in the term "Registrable Securities" for all purposes of this
Agreement.

                                   SECTION 8

                                   Covenants

         The Company covenants and agrees as follows:

                  8.1 Information Rights. So long as any of the Shares are
outstanding, the Company will deliver to holders of the Shares the following:



                                      13
<PAGE>   14

                      (i) as soon as practicable but in any event within ninety
(90) days after the close of each fiscal year of the Company, (A) a
consolidated balance sheet of the Company as of the end of such fiscal year,
(B) consolidated statements of operations, stockholders' equity and cash flows
of the Company for such fiscal year; the Company's Annual Report on Form 10-KSB
shall satisfy such requirement provided that it is in compliance with all
applicable requirements of the SEC and is certified by a "Big Five" accounting
firm; and (C) a certificate of the Chief Financial Officer, Chief Executive
Officer or the President certifying the Company's compliance with the covenants
contained in Section 8.3 of this Agreement; the Company's Annual Report on Form
10-KSB shall satisfy the requirements of clauses (A) and (B), provided that it
is in compliance with all applicable requirements of the SEC;

                      (ii) as soon as practicable, copies of (A) all financial
statements, proxy material or reports sent to the Company's stockholders, (B)
any public press releases and (C) all reports or registration statements filed
with the SEC pursuant to the Securities Act or the Securities Exchange Act;

                      (iii) as soon as practicable and in any event within
forty-five (45) days after the close of each of the first three (3) fiscal
quarters of the Company, (A) a consolidated balance sheet of the Company as of
the end of such fiscal quarter, (B) consolidated statements of operations,
stockholders' equity and cash flows of the Company for the portion of the
fiscal year ended with the end of such quarter and (C) a certificate of the
Chief Financial Officer, Chief Executive Officer or the President certifying
the Company's compliance with the covenants contained in Section 8.3 of this
Agreement; the Company's Quarterly Report on Form 10-QSB shall satisfy the
requirements of clauses (A) and (B), provided that it is in compliance with all
applicable requirements of the SEC;

                      (iv) as soon as practicable and without duplication of any
of the above items, any other materials furnished to holders of the Company's
capital stock; and

                      (v) as soon as practicable, such other information as may
reasonably be requested by holders of the Shares.

                  8.2 Amendment of Certificate of Incorporation. The Company
will use its best efforts, subject to the requirements of relevant federal
securities laws and state corporate law, to file an amendment to its
Certificate of Incorporation, increasing the number of authorized shares of
Class A Common Stock, so that the Company will have sufficient shares of Class
A Common Stock reserved for issuance upon the conversion of the Series B
Preferred Stock.

                  8.3 Negative Covenants. The Company covenants and agrees that
without the prior written consent of the holders of more than 66 2/3% of the
Shares, it will not:

         (i) issue any class or series of equity or equity-linked security
         senior or pari passu to the Preferred Stock as to payment of dividends
         or payments on liquidation or winding up



                                      14
<PAGE>   15

         of the Company; (ii) enter into any agreement that would restrict the
         Company's right to perform under this Agreement; (iii) incur debt or
         encumber its assets above $10 million; (iv) amend the certificate of
         incorporation or bylaws in any manner which would impair or reduce the
         rights of the Preferred Stock; (v) liquidate or dissolve; (vi) go
         private; (vii) redeem or repurchase any outstanding stock except
         pursuant to employee stock option or similar plans; or (viii) enter
         into any other line of business other than a business substantially
         similar or related to the existing business.

                                   SECTION 9

                                 Miscellaneous

                  9.1 Governing Law. This Agreement shall be governed in all
respects by the laws of the State of New York.

                  9.2 Successors and Assigns. Except as otherwise expressly
provided herein, the provisions hereof shall inure to the benefit of, and be
binding upon, the successors, assigns, heirs, executors and administrators of
the parties hereto; provided, however, the Company may not assign its rights
hereunder; and provided, further, that the Company shall be under no obligation
to disclose to any non-Purchaser transferee (other than a transferee who or
which is an "affiliate" of such transferring Purchaser, as such term is defined
in Rule 12b-2 of the Exchange Act) any confidential information otherwise
required to be disclosed by the Company hereunder.

                  9.3 Entire Agreement; Amendment. This Agreement (including
the Schedules and Exhibits hereto) and the other documents delivered pursuant
hereto constitute the full and entire understanding and agreement between the
parties with regard to the subjects hereof and thereof. Neither this Agreement
nor any term hereof may be amended, waived, discharged or terminated, except by
a written instrument signed by the Company and those Purchasers holding in the
aggregate not less than a majority of the outstanding Shares held by the
Purchasers.

                  9.4 Notices, etc. All notices and other communications
required or permitted hereunder shall be in writing and shall be deemed to have
been duly given: (a) on the date of delivery, if delivered to the persons
identified below; (b) seven calendar days after mailing, if mailed, with proper
postage, by certified or registered first-class mail, postage prepaid, return
receipt requested, addressed (i) if to a Purchaser, at the address set forth
for such Purchaser on the Schedule of Purchasers attached hereto or at such
other address as such Purchaser shall have furnished to the Company in writing,
or (ii) if to any other holder of Shares or any Common Stock issued upon
conversion of Shares at such address as such holder shall have furnished the
Company in writing, or, until any such holder so furnishes an address to the
Company, then to and at the address of the last holder thereof who has so
furnished an address to the Company, or (iii) if to the Company, at 6006 North
Mesa Street, Suite 515, El Paso, Texas 79912, Attention: Chief Executive
Officer, or at such other address as the Company shall have furnished to the
Purchasers and each such other holder in writing, with a copy to Fulbright &
Jaworski L.L.P.,



                                      15
<PAGE>   16

666 Fifth Avenue, New York, NY 10103, Attention: Sheldon G. Nussbaum, Esq.; (c)
on the date of receipt if sent by telecopy, and confirmed in writing in the
manner set forth in (b) on or before the next day after the sending of the
telecopy; or (d) one business day after delivery to a nationally recognized
overnight courier service marked for overnight delivery in the manner set forth
in (b). Notwithstanding the foregoing, notices of conversion must be sent by
holders of Shares pursuant to the methods set forth in both (c) and (d) above,
with such notices of conversion to be deemed first given at the earlier time
that delivery under each such method may be deemed given.

                   9.5 Separability. In case any provision of the Agreement
shall be invalid, illegal or unenforceable, the validity, legality and
enforceability of the remaining provisions shall not in any way be affected or
impaired thereby.

                  9.6 Broker's Fees. (a) The Company (i) represents and
warrants that the Company has not retained a finder or broker in connection
with the transactions contemplated by this Agreement and (ii) hereby agrees to
indemnify and to hold the Purchasers harmless of and from any liability for
commission or compensation in the nature of an agent's fee to any broker or
other person or firm incurred in connection with the transactions contemplated
hereby (and the costs and expenses of defending against such liability or
asserted liability) arising from any act by the Company or any of its employees
or representatives.

                      (b) Each of the Purchasers, severally and not jointly, (i)
represents and warrants that it has retained no finder or broker in connection
with the transactions contemplated by this Agreement and (ii) hereby agrees to
indemnify and to hold the Company and the other Purchasers harmless from any
liability for any commission or compensation in the nature of an agent's fee to
any broker or other person or firm incurred in connection with the transactions
contemplated hereby (and the costs and expenses of defending against such
liability or asserted liability) arising from any act by such Purchaser or any
of its employees or representatives.

                  9.7 Expenses. Each of the Company and the Purchasers shall
bear its own expenses and legal fees incurred on its behalf with respect to
this Agreement and the transactions contemplated hereby, except that the
Company shall reimburse the Purchasers up to a maximum of $15,000 for due
diligence and legal expenses.

                  9.8 Titles and Subtitles. The titles of the paragraphs and
subparagraphs of this Agreement are for convenience of reference only and are
not to be considered in construing this Agreement.

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




                                      16
<PAGE>   17

                  IN WITNESS WHEREOF, each of the parties has executed this
Agreement as of the date above written.

                                        CAMBIO, INC., a Delaware corporation



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


                                        PURCHASER:



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






                                      17
<PAGE>   18

                                  CAMBIO, INC.

                             SCHEDULE OF PURCHASERS


<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------------

Name of Purchaser                                   Shares of Series B               Total Investment
-----------------                                   Preferred Stock                  ----------------
                                                    ------------------
---------------------------------------------------------------------------------------------------------

<S>                                                  <C>                             <C>
Frederick R. Adler                                       15,296                          $1,529,600
1520 South Ocean Blvd.
Palm Beach, FL 33480
---------------------------------------------------------------------------------------------------------

Euro-America-II, L.P.                                     7,027                          $  702,700
c/o Venad Administrative Services, Inc.
342 Madison Avenue
New York, NY 10173
---------------------------------------------------------------------------------------------------------

Philip Chapman                                              300                          $   30,000
c/o Venad Administrative Services, Inc.
342 Madison Avenue
New York, NY 10173
---------------------------------------------------------------------------------------------------------

Susan R. Chapman                                            200                          $   20,000
c/o Venad Administrative Services, Inc.
342 Madison Avenue
New York, NY 10173
---------------------------------------------------------------------------------------------------------

Carl Kaplan                                                 150                          $   15,000
c/o Fulbright & Jaworski L.L.P.
666 Fifth Avenue
New York, NY 10103
---------------------------------------------------------------------------------------------------------

Bernard Marden                                            2,000                          $  200,000
1290 South Ocean Blvd.
Palm Beach, FL 33480
---------------------------------------------------------------------------------------------------------

Jay Nickse                                                  100                          $   10,000
77 Putting Green Road
Trumbull, CT 06611
---------------------------------------------------------------------------------------------------------

Joseph K. Pagano                                          1,000                          $  100,000
434 E. Cooper Street
Suite 201
Aspen, CO 81611
---------------------------------------------------------------------------------------------------------
</TABLE>



                                       1
<PAGE>   19

<TABLE>
<S>                                                  <C>                             <C>
---------------------------------------------------------------------------------------------------------
Berol Family Trust FBO Margaret Beattie                  1,000                           $  100,000
c/o Trainer, Wortham
845 Third Avenue, 6th Floor
New York, NY 10022
---------------------------------------------------------------------------------------------------------

Trust U/W Kenneth Berol FBO John A. Berol                1,000                           $  100,000
c/o Trainer, Wortham
845 Third Avenue, 6th Floor
New York, NY 10022
---------------------------------------------------------------------------------------------------------

Trust U/W Kenneth Berol FBO David N. Berol               1,000                           $  100,000
c/o Trainer, Wortham
845 Third Avenue, 6th Floor
New York, NY 10022
---------------------------------------------------------------------------------------------------------

A. Alexander Arnold III                                    500                           $   50,000
c/o Trainer, Wortham
845 Third Avenue, 6th Floor
New York, NY 10022
---------------------------------------------------------------------------------------------------------

Jim Joy                                                  1,000                           $  100,000
c/o CVC Capital
Citicorp Venture Capital
Floor 14, Zone 4
399 Park Avenue
New York, NY 10043
---------------------------------------------------------------------------------------------------------

Anthony Pantaleoni                                         500                           $   50,000
c/o Fulbright & Jaworski L.L.P.
666 Fifth Avenue
New York, NY 10103
---------------------------------------------------------------------------------------------------------

C. Nicholas Potter                                         600                           $   60,000
120 Horseshoe Road
Mill Neck, NY 11765
---------------------------------------------------------------------------------------------------------

Chance Vought                                            2,500                           $  250,000
c/o Providence Capital
19 Fulton Street, Suite 306
New York, NY 10038
---------------------------------------------------------------------------------------------------------

The Travelers Insurance Company                          9,000                           $  900,000
388 Greenwich Street
New York, NY 10013
---------------------------------------------------------------------------------------------------------
</TABLE>

                                       2
<PAGE>   20

<TABLE>
<S>                                                  <C>                             <C>
---------------------------------------------------------------------------------------------------------
Robert Annunziata                                        400                             $   40,000
95 Minnisink Road
Short Hills, NJ 07078
---------------------------------------------------------------------------------------------------------

Excess Capital LLC                                       200                             $   20,000
1 West 67th Street- #310
New York, NY 10023
Attn: John Stuart
---------------------------------------------------------------------------------------------------------

Gary and Stephanie Escandon                              400                             $   40,000
204 New York Blvd.
Sea Girt, NJ 08750
---------------------------------------------------------------------------------------------------------

Thomas Finnegan III                                      200                             $   20,000
943 Whitepoint Court
Charleston, SC 29412
---------------------------------------------------------------------------------------------------------

Andrea Fraenkel                                          200                             $   20,000
253 Hartshorn Drive
Short Hills, NJ 07078
---------------------------------------------------------------------------------------------------------

Fred Fraenkel                                            200                             $   20,000
253 Hartshorn Drive
Short Hills, NJ 07078
---------------------------------------------------------------------------------------------------------

Hollywell Investments Pty Ltd.                           400                             $   40,000
Level 52- Rialto South Tower
525 Collins Street
Melbourne VIC 3000, Australia
Attn: Michael Karp
---------------------------------------------------------------------------------------------------------

Elise Kimmel                                             400                             $   40,000
76 Old Hollow Road
Short Hills, NJ 07078
---------------------------------------------------------------------------------------------------------

Jagen Nominees Pty Ltd (ACN 073 513 738)                 400                             $   40,000
Level 9, 161 Collins Street
Melbourne 3000
Australia
Attn: Bori Liberman
---------------------------------------------------------------------------------------------------------

Norman Merksamer                                         400                             $   40,000
64 Lincoln Road
Scarsdale, NY 10583
---------------------------------------------------------------------------------------------------------
</TABLE>



                                       3
<PAGE>   21

<TABLE>
<S>                                                  <C>                             <C>
---------------------------------------------------------------------------------------------------------
Frederick W. Moran                                         400                           $   40,000
ING Baring Furman Selz LLC
55 East 52nd Street-15th Floor
New York, NY 10055
---------------------------------------------------------------------------------------------------------

Janet Toledano                                             200                           $   20,000
51 Duffield
South Orange, NJ 07079
---------------------------------------------------------------------------------------------------------

Udi Toledano                                               200                           $   20,000
c/o Andromeda Enterprises, Inc.
545 Madison Avenue
New York, NY 10022
---------------------------------------------------------------------------------------------------------

Marshall Tycher                                            400                           $   40,000
c/o Roseland Property Company
140 Eagle Rock Avenue
Roseland, NJ 07068
---------------------------------------------------------------------------------------------------------

Gari Grimm                                               1,500                           $  150,000
2005 East Lake Sammamish Place S.E.
Issaquah, WA 98029
---------------------------------------------------------------------------------------------------------

Phifer Consulting Group, Inc.                            2,000                           $  200,000
P.O. Box 119
Lakewood, WA 98259
---------------------------------------------------------------------------------------------------------


                           Total                                                         $5,107,300
                                                                                         ==========

</TABLE>

                                       4