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                                                                   Exhibit 10.48



                   SERIES C PREFERRED STOCK WARRANT AGREEMENT



                                  by and among



                          HOUSTONSTREET EXCHANGE, INC.



                                       and



                      THE PERSONS LISTED ON ANNEX I HERETO






                           Dated as of March 30, 2001
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         SERIES C PREFERRED STOCK WARRANT AGREEMENT, dated as of March 30, 2001
among HOUSTONSTREET EXCHANGE, INC., a Delaware corporation (the "Company") and
the persons and entities listed on Annex I hereto (each a "Holder", and
collectively, the "Holders" ).

         WHEREAS, in connection with a private placement of up to (i)
$13,617,015 aggregate principal amount of Senior Secured Notes (each a "Note"
and collectively the "Notes"), (ii) Series C Preferred Stock purchase warrants
(the "Preferred Warrants"), and (iii) Common Stock Purchase Warrants, pursuant
to the terms of a Senior Note and Warrant Purchase Agreement of even date
herewith (the "Note Purchase Agreement") the Company will issue to the Holders
Warrants to purchase an aggregate of up to 90,780,100 shares of Series C
Convertible Preferred Stock, par value $.01 per share, of the Company (the
"Series C Preferred Stock"), subject to adjustment.

         NOW THEREFORE, in consideration of the agreements herein set forth and
other good and valuable consideration, the sufficiency of which is hereby
acknowledged, the parties agree as follows:

         1. Grant and Exercise of Warrants. The Company hereby grants to each
Holder or its successors or registered assigns the right to purchase (each a
"Warrant" and collectively, the "Warrants"), at any time or from time to time
beginning on the date of issuance of the Warrant and ending at 5:00 p.m. E.S.T.
on the seventh (7th) calendar day following payment in full of such Holder's
Note, up to such number of fully paid and nonassessable shares of Series C
Preferred Stock (the "Warrant Shares"), at an exercise price per share of $0.15
per share of Series C Preferred Stock (as such price may be adjusted pursuant to
the terms hereof, the "Exercise Price"), set forth opposite such Warrant
Holder's name on Annex I hereto plus such additional number of shares of Series
C Preferred Stock as may be requested by such Holder as provided by Section 2 of
the Senior Secured Promissory Note issued in favor of such Holder.

         2. Warrant Certificates. The warrant certificates (the "Warrant
Certificates") representing the Warrant Shares delivered and to be delivered to
each Holder pursuant to this Agreement shall be in the form set forth in Exhibit
A, attached hereto and made a part hereof, with such appropriate insertions,
omissions, substitutions, and other variations as required or permitted by this
Agreement.

         3. Registration of Warrant Certificates. The Warrant Certificates shall
be numbered and shall be registered on the books of the Company when issued.

         4. Exercise of the Warrants. The Warrants initially are exercisable at
the Exercise Price set forth in Section 1 hereof, which shall be payable for the
shares of Series C Preferred Stock to be issued upon such exercise in one of the
following manners, at the option of the Holder:

                  (i)      delivery of a certified check, cashier's check, cash,
                           or wire transfer of the purchase price for such
                           shares;

                  (ii)     delivery to the Company for cancellation (or partial
                           cancellation, as the case may be) of the Note from
                           the Company to the Holder as the purchase
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                           price for such shares (in the case of the
                           cancellation of less than all of the Note, the
                           Company shall cancel said Note upon the surrender
                           thereof and shall execute and deliver a new Note of
                           like tenor for the balance of the principal amount
                           payable thereunder); or

                  (iii)    a combination of any of the methods set forth in (i)
                           or (ii) above.

         Upon surrender of a Warrant Certificate with the annexed Form of
Election to Purchase duly executed, together with payment of the Exercise Price
for the Warrant Shares to be purchased, at the Company's principal offices,
currently located at 222 International Drive, Suite 125, Portsmouth, NH 03801,
the registered holder of a Warrant Certificate ("Holder" or "Holders") shall be
entitled to receive a certificate or certificates for the Warrant Shares so
purchased. The purchase rights represented by each Warrant Certificate are
exercisable at the option of the Holder thereof, in whole or in part (but not as
to fractional shares of Common Stock underlying the Warrant). In the case of the
purchase of less than all of the Warrant Shares purchasable under any Warrant
Certificate, the Company shall cancel said Warrant Certificate upon the
surrender thereof and shall execute and deliver a new Warrant Certificate of
like tenor for the balance of the Warrant Shares purchasable thereunder.

         5. Issuance of Certificates. Upon the exercise of a Warrant, the
issuance of certificates for Warrant Shares shall be made forthwith (and in any
event within ten (10) business days thereafter) without charge to the Holder
thereof including, without limitation, any tax, other than income taxes which
may be payable in respect of the issuance thereof, and such certificates shall
(subject to the provisions of Sections 6 and 7 hereof) be issued in the name of,
or in such names as may be directed by, the Holder thereof; provided, however,
that the Company shall not be required to pay any transfer tax which may be
payable in respect of any transfer involved in the issuance and delivery of any
such certificates in a name other than that of the Holder and the Company shall
not be required to issue or deliver such certificates unless or until the person
or persons requesting the issuance thereof shall have paid to the Company the
amount of such tax or shall have established to the satisfaction of the Company
that such tax has been paid.

         Each Warrant Certificate and any certificate representing Warrant
Shares or other securities, property or rights issued upon exercise of a Warrant
shall be executed on behalf of the Company by the manual or facsimile signature
of the then present President or any Vice President of the Company under its
corporate seal reproduced thereon, attested to by the manual or facsimile
signature of the then Secretary or any Assistant Secretary of the Company. Each
Warrant Certificate shall be dated the date of execution by the Company upon
initial issuance, division, exchange, substitution or transfer.

         6. Transfer of a Warrant. A Warrant shall be transferable only on the
books of the Company maintained at its principal office, where its principal
office may then be located, upon delivery thereof duly endorsed by the Holder or
by its duly authorized attorney or representative accompanied by proper evidence
of succession, assignment or authority to transfer. Upon any registration
transfer, the Company shall execute and deliver a new Warrant to the person
entitled thereto.

         7.       Restrictions on Transfer of the Warrant.

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                  7.1 Any Warrant Shares issued will not be registered under the
Securities Act of 1933, as amended (the "Securities Act"), and the Holder agrees
to acquire any Warrant Shares for investment (which is understood to mean that
Holder must intend to retain such Warrant Shares indefinitely without any
intention of reselling or otherwise disposing of them either presently or at the
expiration of any particular period unless they are subsequently registered
under the Securities Act or an exemption from registration is available). It is
further understood that any sales of Warrant Shares made in reliance upon Rule
144 under the Securities Act can be made only in limited amounts in accordance
with the terms and conditions of that Rule 144, and that such Rule 144 is not
presently available with respect to the sale of any Warrant Shares. The Holder
agrees to be bound by the provisions of a legend substantially similar to the
following which will be endorsed upon the stock certificate to be issued for any
Warrant Shares issued:

                  "The securities represented by this certificate have not been
                  registered under the Securities Act of 1933, as amended (the
                  "Securities Act") or any state securities laws, have been
                  acquired for investment, and may not be sold, pledged,
                  hypothecated or otherwise transferred unless a registration
                  statement under the Securities Act and any applicable state
                  law is in effect with regard thereto or an exemption from such
                  registration is available."

                  7.2 It is understood that the Company is not obligated to
register any Warrant Shares (nor has the Company represented to the Holder that
it will register any of the Warrant Shares) or to comply with the terms of any
exemption from registration and that the Company may place a "Stop Transfer
Order" against such shares until one of the conditions set forth in the
foregoing legend shall have been met.

         8. Exercise Price and Number of Securities. Each Warrant is exercisable
to purchase Warrant Shares at an initial exercise price equal to the Exercise
Price. The Exercise Price and the number of Warrant Shares for which each
Warrant may be exercised shall be the price and the number of Warrant Shares
which shall result from time to time from any and all adjustments in accordance
with the provisions of Section 9 hereof.

         9. Adjustments to Exercise Price and Number of Securities. The Exercise
Price in effect at any time and the number and kind of securities purchased upon
the exercise of the Warrant shall be subject to adjustment from time to time
only upon the happening of the following events:

                  9.1 Stock Dividend, Subdivision and Combination. In case the
Company shall (i) declare a dividend or make a distribution on its outstanding
shares of Series C Preferred Stock in shares of Series C Preferred Stock, (ii)
subdivide its outstanding shares of Series C Preferred Stock into a greater
number of shares, or (iii) combine its outstanding shares of Series C Preferred
Stock into a smaller number of shares, the Exercise Price in effect at the time
of the record date for such dividend or distribution or of the effective date of
such subdivision, combination or reclassification shall be adjusted so that it
shall equal the price determined by multiplying the Exercise Price by a
fraction, the denominator of which shall be the number of shares of Series C
Preferred Stock outstanding

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after giving effect to such action, and the numerator of which shall be the
number of shares of Series C Preferred Stock outstanding immediately prior to
such action. Such adjustment shall be made successively whenever any event
listed above shall occur.

                  9.2 Adjustments for Diluting Issues.

                           (a) Special Definitions. For purposes of this Section
                  9.2, the following definitions shall apply:

                                    "Option" shall mean rights, options or
                           warrants to subscribe for, purchase or otherwise
                           acquire Common Stock or Convertible Securities.

                                    "Series C Warrant Original Issue Date" shall
                           mean the date hereof.

                                    "Convertible Securities" shall mean any
                           evidences of indebtedness, shares or other
                           securities, directly or indirectly, convertible into
                           or exchangeable for Common Stock, but excluding
                           Options.

                                    "Additional Shares of Common Stock" shall
                           mean all shares of Common Stock issued (or, pursuant
                           to Subsection 9.2(c) below, deemed to be issued) by
                           the Company after the Series C Warrant Issue Date,
                           other than:

                                             (i) shares of Common Stock issued
                                    or issuable upon conversion or exchange of
                                    any Convertible Securities or exercise of
                                    any Options outstanding on the Series C
                                    Warrant Original Issue Date;

                                             (ii) shares of Common Stock issued
                                    or issuable as a dividend or distribution on
                                    Series A Convertible Preferred Stock, Series
                                    B Convertible Preferred Stock or Series C
                                    Preferred Stock of the Company;

                                             (iii) shares of Common Stock issued
                                    or issuable by reason of a dividend, stock
                                    split, split-up or other distribution on
                                    shares of Common Stock that is covered by
                                    Subsection 9.1;

                                             (iv) shares of Common Stock issued
                                    or issuable in connection with a merger,
                                    acquisition or consolidation;

                                             (v) not in excess of 40,000,000
                                    shares of Common Stock (or Options with
                                    respect thereto) (in each case, subject to
                                    appropriate adjustment in the event of any
                                    stock dividend, stock split, combination or
                                    other similar recapitalization affecting
                                    such shares) issued or issuable to employees
                                    or directors of, or advisors or consultants
                                    to, the Company pursuant to a plan or
                                    arrangement approved by the Board of
                                    Directors of the Company;

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                                             (vi) shares of Common Stock (or
                                    Convertible Securities or warrants with
                                    respect thereto) issued or issuable upon
                                    conversion or exchange of the Common Stock
                                    Warrants and Series C Convertible Preferred
                                    Stock Warrants (the "Warrants") issued
                                    pursuant to the Senior Secured Note and
                                    Warrant Purchase Agreement of even date
                                    herewith, including Warrants issued as
                                    payment of interest under the Senior Secured
                                    Promissory Notes; and

                                             (vii) shares of Common Stock issued
                                    or issuable to Enron Net Works LLC ("Enron")
                                    pursuant to the terms of that certain Common
                                    Stock Purchase Agreement dated as of
                                    September 20, 2000 and issued or issuable to
                                    Enron upon exercise of that certain Warrant,
                                    dated as of December 4, 2000.

                           (b) No Adjustment of Exercise Price. No adjustment in
         the Exercise Price shall be made as the result of the issuance of
         Additional Shares of Common Stock if: (i) the consideration per share
         (determined pursuant to Subsection 9.2(e) for such Additional Shares of
         Common Stock issued or deemed to be issued by the Company is equal to
         or greater than the applicable Exercise Price in effect immediately
         prior to the issuance or deemed issuance of such Additional Shares, or
         (ii) prior to such issuance or deemed issuance, the Company receives
         written notice from the holders of not less than 95% of the then
         outstanding shares of Series C Preferred Stock agreeing that no such
         adjustment shall be made as the result of the issuance or deemed
         issuance of Additional Shares of Common Stock.

                           (c) Issue of Securities Deemed Issue of Additional
         Shares of Common Stock. If the Company at any time or from time to time
         after the Series C Warrant Original Issue Date shall issue any Options
         (excluding Options covered by Subsection 9.2(a)(v) and Warrants covered
         by Subsection 9.2(a)(vi) above) or Convertible Securities (excluding
         Convertible Securities covered by Subsection 9.2(a)(vi) above) or shall
         fix a record date for the determination of holders of any class of
         securities entitled to receive any such Options or Convertible
         Securities, then the maximum number of shares of Common Stock (as set
         forth in the instrument relating thereto without regard to any
         provision contained therein for a subsequent adjustment of such number)
         issuable upon the exercise of such Options or, in the case of
         Convertible Securities and Options therefor, the conversion or exchange
         of such Convertible Securities, shall be deemed to be Additional Shares
         of Common Stock issued as of the time of such issue or, in case such a
         record date shall have been fixed, as of the close of business on such
         record date, provided that Additional Shares of Common Stock shall not
         be deemed to have been issued unless the consideration per share
         (determined pursuant to Subsection 9.2(e) hereof) of such Additional
         Shares of Common Stock would be less than the applicable Exercise Price
         in effect on the date of and immediately prior to such issue, or such
         record date, as the case may be, and provided further that in any such
         case in which Additional Shares of Common Stock are deemed to be
         issued:

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                                    (i) No further adjustment in the Exercise
         Price shall be made upon the subsequent issue of Convertible Securities
         or shares of Common Stock upon the exercise of such Options or
         conversion or exchange of such Convertible Securities;

                                    (ii) If such Options or Convertible
         Securities by their terms provide, with the passage of time or
         otherwise, for any increase or decrease in the consideration payable to
         the Company, then upon the exercise, conversion or exchange thereof,
         the Exercise Price computed upon the original issue thereof (or upon
         the occurrence of a record date with respect thereto), and any
         subsequent adjustments based thereon, shall, upon any such increase or
         decrease becoming effective, be recomputed to reflect such increase or
         decrease insofar as it affects such Options or the rights of conversion
         or exchange under such Convertible Securities;

                                    (iii) Upon the expiration, redemption or
         termination of any such unexercised Option or unconverted Convertible
         Security, the Exercise Price shall not be readjusted, but the
         Additional Shares of Common Stock deemed issued as the result of the
         original issue of such Option or Convertible Security shall not be
         deemed issued for the purposes of any subsequent adjustment of the
         Exercise Price;

                                    (iv) In the event of any change in the
         number of shares of Common Stock issuable upon the exercise, conversion
         or exchange of any such Option or Convertible Security, including, but
         not limited to, a change resulting from the anti-dilution provisions
         thereof, the Exercise Price then in effect shall forthwith be
         readjusted to such Exercise Price as would have obtained had the
         adjustment which was made upon the issuance of such Option or
         Convertible Security not exercised, converted or exchanged prior to
         such change been made upon the basis of such change; and

                                    (v) No readjustment pursuant to clause (ii),
         (iii) or (iv) above shall have the effect of increasing the Exercise
         Price to an amount which exceeds the lower of (1) the Exercise Price on
         the original adjustment date, or (2) the Exercise Price that would have
         resulted from any issuances of Additional Shares of Common Stock
         between the original adjustment date and such readjustment date.

                  In the event the Company, after the Series C Warrant Original
         Issue Date, amends the terms of any such Options or Convertible
         Securities (whether such Options or Convertible Securities were
         outstanding on the Series C Warrant Original Issue Date or were issued
         after the Series C Warrant Original Issue Date ), then such Options or
         Convertible Securities, as so amended, shall be deemed to have been
         issued after the Series C Warrant Original Issue Date and the
         provisions of this Subsection 9.2(c) shall apply.

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                           (d) Adjustment of Exercise Price Upon Issuance of
         Additional Shares of Common Stock. In the event the Company shall at
         any time after the Series C Warrant Original Issue Date issue
         Additional Shares of Common Stock (including Additional Shares of
         Common Stock deemed to be issued pursuant to Subsection 9.2(c)),
         without consideration or for a consideration per share less than the
         applicable Exercise Price in effect immediately prior to such issue,
         then and in such event, such Exercise Price shall be reduced,
         concurrently with such issue, to a price (calculated to the nearest
         cent) equal to the issue price of such Additional Shares.

                           (e) Determination of Consideration. For purposes of
         this Section 9.2, the consideration received by the Company for the
         issue of any Additional Shares of Common Stock shall be computed as
         follows:

                                    (i) Cash and Property. Such consideration
                           shall:

                                             (1) insofar as it consists of cash,
                           be computed at the aggregate of cash received by the
                           Company, excluding amounts paid or payable for
                           accrued interest or dividends;

                                             (2) insofar as it consists of
                           property other than cash, be computed at the fair
                           market value thereof at the time of such issue, as
                           determined in good faith by the Board of Directors;
                           and

                                             (3) in the event Additional Shares
                           of Common Stock are issued together with other shares
                           or securities or other assets of the Company for
                           consideration which covers both, be the proportion of
                           such consideration so received, computed as provided
                           in clauses (1) and (2) above, as determined in good
                           faith by the Board of Directors.

                                    (ii) Options and Convertible Securities. The
                           consideration per share received by the Company for
                           Additional Shares of Common Stock deemed to have been
                           issued pursuant to Subsection 9.2(c), relating to
                           Options and Convertible Securities, shall be
                           determined by dividing:

                                             (x) the total amount, if any,
                                    received or receivable by the Company as
                                    consideration for the issue of such Options
                                    or Convertible Securities, plus the minimum
                                    aggregate amount of additional consideration
                                    (as set forth in the instruments relating
                                    thereto, without regard to any provision
                                    contained therein for a subsequent
                                    adjustment of such consideration) payable to
                                    the Company upon the exercise of such
                                    Options or the conversion or exchange of
                                    such Convertible Securities, or in the case
                                    of Options for Convertible Securities, the
                                    exercise of such Options for Convertible
                                    Securities and the conversion or exchange of
                                    such Convertible Securities, by

                                             (y) the maximum number of shares of
                                    Common Stock (as set forth in the
                                    instruments relating thereto, without regard
                                    to

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                                    any provision contained therein for a
                                    subsequent adjustment of such number)
                                    issuable upon the exercise of such Options
                                    or the conversion or exchange of such
                                    Convertible Securities.

                           (f) Multiple Closing Dates. In the event the Company
shall issue on more than one date Additional Shares of Common Stock which are
comprised of shares of the same series or class of Preferred Stock into which
the Warrants convert, and such issuance dates occur within a period of no more
than 120 days, then, upon the final such issuance, the Exercise Price shall be
readjusted to give effect to all such issuances as if they occurred on the date
of the final such issuance (and without giving effect to any adjustments as a
result of such prior issuances within such period).

                  9.3 Certificate as to Adjustments. Upon the occurrence of each
adjustment or readjustment of the Exercise Price pursuant to this Section 9, the
Company at its expense shall promptly compute such adjustment or readjustment in
accordance with the terms hereof and furnish to each Holder a certificate
setting forth such adjustment or readjustment and showing in detail the facts
upon which such adjustment or readjustment is based.

                  9.4 Adjustment in Number of Securities. Upon each adjustment
of the Exercise Price pursuant to the provisions of Section 9.1 hereof, the
number of Warrant Shares issuable upon the exercise of each Warrant at the
adjusted Exercise Price shall be adjusted to the nearest number of whole shares
of Series C Preferred Stock obtained by multiplying a number equal to the
Exercise Price in effect immediately prior to such adjustment by the number of
Warrant Shares issuable upon exercise of the Warrant immediately prior to such
adjustment and dividing the product so obtained by the adjusted Exercise Price.

                  9.5 Merger or Consolidation. In case of any consolidation of
the Company with, or merger of the Company into, another corporation (other than
a consolidation or merger which does not result in any reclassification or
change of the outstanding Common Stock and Series C Preferred Stock), the
corporation formed by such consolidation or merger shall execute and deliver to
the Holder a supplemental warrant agreement providing that the Holder of each
Warrant then outstanding or to be outstanding shall have the right thereafter
(until the expiration of such Warrant) to receive, upon exercise of such
Warrant, the kind and amount of shares of stock and other securities and
property receivable upon such consolidation or merger by a holder of the number
of shares of Series C Preferred Stock for which such Warrant might have been
exercised immediately prior to such consolidation, merger, sale or transfer.
Such supplemental warrant agreement shall provide for adjustments which shall be
identical to the adjustments provided in Section 9. The above provision of this
subsection shall similarly apply to successive consolidations or mergers.

                  9.6 Exchange and Replacement of the Warrant Certificates. Each
Warrant Certificate is exchangeable, without expense, upon the surrender thereof
by the registered Holder at the principal executive office of the Company for a
new Warrant Certificate of like tenor and date representing in the aggregate the
right to purchase the same number of Warrant Shares purchasable thereunder in
such denominations as shall be designated by the Holder thereof at the time of
such surrender.

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                  9.7 Certain Definitions.

                           (a) For the purpose of this Agreement, the term
                  "Common Stock" shall mean (i) the class of stock designated as
                  Common Stock in the Amended and Restated Certificate of
                  Incorporation of the Company, or (ii) any other class of stock
                  resulting from successive changes or reclassifications of such
                  Common Stock consisting solely of changes in par value, or
                  from par value to no par value, or from no par value to par
                  value.

                           (b) For the purpose of this Agreement, the term
                  "Series C Preferred Stock" shall mean (i) the class of stock
                  designated as Series C Convertible Preferred Stock in the
                  Amended and Restated Certificate of Incorporation of the
                  Company, or (ii) any other class of stock resulting from
                  successive changes or reclassifications of such Series C
                  Preferred Stock consisting solely of changes in par value, or
                  from par value to no par value, or from no par value to par
                  value.

         10. Theft or Destruction of Certificates. Upon receipt by the Company
of evidence reasonably satisfactory to it of the loss, theft, destruction or
mutilation of any Warrant Certificate, and, in the case of loss, theft or
destruction, an indemnity or security reasonably satisfactory to it and
reimbursement to the Company of all reasonable expenses incidental thereto, and
upon surrender and cancellation of the Warrant, if mutilated, the Company will
make and deliver a new Warrant Certificate of like tenor, in lieu thereof.

         11. Elimination of Fractional Interests. The Company shall not be
required to issue certificates representing fractions of shares of Series C
Preferred Stock upon the exercise of the Warrant, nor shall it be required to
issue scrip or pay cash in lieu of fractional interests, it being the intent of
the parties that all fractional interests shall be eliminated by rounding any
fraction up to the nearest whole number of shares of Series C Preferred or other
securities, properties or rights, on one occasion only for each Holder.

         12. Reservation of Securities. The Company shall at all times reserve
and keep available out of its authorized shares of Series C Preferred Stock,
solely for the purpose of issuance upon the exercise of a Warrant, such number
of shares of Series C Preferred Stock or other securities, properties or rights
as shall be issuable upon the exercise thereof (assuming an exercise price of
the Warrant of not less than $0.10 per share of Series C Preferred Stock). Every
transfer agent ("Transfer Agent") for the Series C Preferred Stock and other
securities of the Company issuable upon the exercise of a Warrant will be
irrevocably authorized and directed at all times to reserve such number of
authorized shares of Series C Preferred Stock and other securities as shall be
requisite for such purpose (assuming an exercise price of the Warrant of not
less than $0.10 per share of Series C Preferred Stock). The Company will keep a
copy of this Agreement on file with every Transfer Agent for the Series C
Preferred Stock and other securities of the Company issuable upon the exercise
of the Warrant. The Company will supply every such Transfer Agent with duly
executed stock and other certificates, as appropriate, for such purpose.
Initially, the Transfer Agent shall be the Company. The Company covenants and
agrees that, (a) upon exercise of a Warrant and payment of the Exercise Price
therefor, all shares of Series C Preferred Stock and other securities issuable
upon such exercise shall be duly and validly issued, fully paid, non-assessable,
free from all taxes, liens and charges with respect to

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the issue thereof and not subject to the preemptive rights of any stockholder,
(b) it will from time to time take all such actions as may be required to assure
that the stated or par value per share of Series C Preferred Stock is at all
times equal to or less than the then effective Exercise Price per Warrant Share
issuable upon exercise of a Warrant and (c) if and so long as the Warrant Shares
issuable upon the exercise of the Warrant are listed on any national securities
exchange, the Company will list and keep listed on such exchange, upon official
notice of issuance, any Warrant Shares.

         13. Notices to Warrant Holders. Nothing contained in this Agreement
shall be construed as conferring upon the Holders the right to vote or to
consent or to receive notice as a stockholder in respect of any meetings of
stockholders for the election of directors or any other matter, or as having any
rights whatsoever as a stockholder of the Company. If, however, at any time
after the Exercise Date and prior to the Holder's exercise of the Warrant, any
of the following events shall occur:

                  (a) the Company shall take a record of the holders of its
         shares of Series C Preferred Stock for the purpose of entitling them to
         receive a dividend or distribution payable otherwise than in cash, or a
         cash dividend or distribution payable otherwise than out of current or
         retained earnings, as indicated by the accounting treatment of such
         dividend or distribution on the books of the Company; or

                  (b) the Company shall offer to all the holders of its Series C
         Preferred Stock any additional shares of capital stock of the Company
         or securities convertible into or exchangeable for shares of capital
         stock of the Company, or any option, right or warrant to subscribe
         therefor; or

                  (c) a dissolution, liquidation or winding up of the Company
         (other than in connection with a consolidation or merger) or a sale of
         all or substantially all of its property, assets and business as an
         entirety shall be proposed;

then in any one or more of said events, the Company shall give written notice of
such event to the holder of the Warrant at least fifteen (15) days prior to the
date fixed as a record date or the date of closing the transfer books for the
determination of the stockholders entitled to such dividend, distribution,
convertible or exchangeable securities or subscription rights, or entitled to
vote on such proposed dissolution, liquidation, winding up or sale. Such notice
shall specify such record date or the date of closing the transfer books, as the
case may be. Failure to give such notice or any defect therein shall not affect
the validity of any action taken in connection with the declaration or payment
of any such dividend, or the issuance of any convertible or exchangeable
securities, or subscription rights, options or warrants, or any proposed
dissolution, liquidation, winding up or sale.

         14. Counterpart Execution. This Agreement may be executed in any number
of counterparts with the same effect as if all of the parties hereto had signed
the same documents. All counterparts shall be construed together and shall
constitute one agreement.

         15. Subsequent Holder. Any future purchaser of Warrants in accordance
with the terms of the Note Purchase Agreement may become a party to this
Agreement after the date

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hereof without the consent of the other parties hereto by executing a
counterpart signature page to this Agreement. Each such party shall be deemed a
Holder hereunder. Annex I hereto shall be amended from time to time to reflect
the addition of any Holder pursuant to this Section 15.


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         IN WITNESS OF, the parties hereto have caused this Agreement to be duly
executed, as of the day and year first above written.


HOUSTONSTREET EXCHANGE, INC.            HOLDER

                                        BAYCORP HOLDINGS, LTD.

By: /s/ Frank W. Getman Jr.             By: /s/ Frank W. Getman Jr.
    ------------------------------          -------------------------------
Name: Frank W. Getman Jr.               Name: Frank W. Getman Jr.
Title: President and Chief              Title: President and Chief
       Executive Officer                       Executive Officer



                                       12
<PAGE>
                                     ANNEX I

                                 LIST OF HOLDERS


<TABLE>
<CAPTION>
       Name and Address of Holder                    No. of Series C
       --------------------------                    ---------------
                                                      Stock Warrants
                                                      --------------
<S>                                                  <C>
BayCorp Holdings, Ltd.                                    56,132,280
     Attn:  Frank W. Getman, Jr.
     222 International Drive, Suite 125
     Portsmouth, NH  03801-6809
TSG Equity Fund, L.P.                                        118,422
     Attn:  Thomas R. Shepherd
     636 Great Road
     Stow, MA  01775
TSG Equity Partners LLC                                        1,196
     Attn:  Thomas R. Shepherd
     636 Great Road
     Stow, MA  01775
Thomas R. Shepherd                                            10,024
     c/o TSG Equity Partners LLC
     636 Great Road
     Stow, MA  01775
T. Nathanael Shepherd                                          3,692
     c/o TSG Equity Partners LLC
     636 Great Road
     Stow, MA  01775
James S. Gordon                                            1,250,000
     86 Mt. Vernon Street
     Boston, MA  02108
Mitchell Jacobs                                              833,334
     1 Energy Road
     North Dartmouth, MA  02747
KRoad Ventures                                             1,066,667
     330 Madison Avenue
     25th Floor
     New York, NY  10017
Equiva Trading Company                                     9,295,693
     Attention:  William J. Finnerty
     One Allen Center
     500 Dallas Street
     Houston, TX  77002
Omega Advisors, Inc.                                         600,000
     Attention: Ed Levy
     Wall Street Plaza
     88 Pine Street, 31st Floor
     New York, NY 10005
Michael A. Desrochers                                        555,553
     c/o MicroArts Corporation
     655 Portsmouth Avenue
     Portsmouth, NH  03840
Barrett McDevitt                                             555,560
     c/o MicroArts Corporation
     655 Portsmouth Avenue
</TABLE>
<PAGE>
<TABLE>
<S>                                                  <C>
     Portsmouth, NH  03840
Peter L. Getman                                              555,553
     c/o MicroArts Corporation
     655 Portsmouth Avenue
     Portsmouth, NH  03840
Conoco, Inc.                                               2,918,793
     600 N. Dairy Ashford
     MA 3128
     Houston, TX  77079-1175
Thomas H. Lee Investors Limited                              500,000
Partnership
     75 State Street
     Boston, MA  02109
</TABLE>


                                       2