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                                                                   EXHIBIT 10.45

                          HOUSTONSTREET EXCHANGE, INC.



                 AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT



         This Agreement dated as of March 30, 2001 amends and restates (i) that
certain Investor Rights Agreement dated as of February 2, 2000 and amended March
6, 2000, March 31, 2000 and December 4, 2000, by and among HoustonStreet Street
Exchange, Inc., a Delaware corporation (the "Company"), BayCorp Holdings, Ltd.,
a Delaware corporation ("BayCorp"), Equiva Trading Company, a Delaware general
partnership ("Equiva"), Enron Net Work LLC, a Delaware limited liability company
("Enron"), and the Purchasers named therein (the "Series A Investor Rights
Agreement") and (ii) that certain Investor Rights Agreement dated as of March
31, 2000 by and among the Company and the holders of Series B Convertible
Preferred Stock, par value $.01 per share, of the Company (the "Series B Stock")
(the "Series B Investor Rights Agreement").

         This Agreement is entered into by and among the Company, BayCorp,
Equiva, Enron, the holders of Series A Convertible Preferred Stock, par value
$.01 per share, of the Company (the "Series A Stock") listed on SCHEDULE A
hereto (the "Series A Stockholders"), the holders of Series B Stock listed on
SCHEDULE A hereto (the "Series B Stockholders") and the purchasers of units
("Units") consisting of (x) Senior Secured Notes, (y) Warrants to purchase
shares of Series C Convertible Preferred Stock, par value $.01 per share of the
Company (the "Series C Stock" and, together with the Series A Stock and the
Series B Stock, the "Preferred Stock") (the "Series C Warrants"), and (z)
Warrants to purchase shares of Common Stock, $.01 par value per share (the
"Common Stock") (the "Common Stock Warrants"), pursuant to that certain Secured
Note and Warrant Purchase Agreement dated as of the date hereof (the "Note and
Warrant Purchase Agreement") listed on SCHEDULE A hereto (the "Unit
Purchasers"). In the event of an Additional Initial Closing (as defined in the
Note and Warrant Purchase Agreement), SCHEDULE A hereto will be amended to
include such purchasers as Unit Purchasers hereunder.
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                                    RECITALS

         1. The Series A Stockholders purchased certain shares of Series A Stock
pursuant to the Series A Convertible Preferred Stock Purchase Agreement dated as
of February 2, 2000 (the "Series A Preferred Stock Purchase Agreement").

         2. Equiva purchased 4,814,815 shares of the Common Stock pursuant to
the Common Stock Purchase Agreement dated as of February 2, 2000.

         3. BayCorp owns of record 10,000,000 shares of Common Stock.

         4. The Series B Stockholders purchased certain shares of Series B Stock
pursuant to the Series B Convertible Preferred Stock Purchase Agreement dated as
of March 31, 2000 (the "Series B Preferred Stock Purchase Agreement").

         5. Enron purchased 1,781,043 shares of Common Stock pursuant to the
Common Stock Purchase Agreement dated as of September 20, 2000.

         6. On December 4, 2000, the Company issued to Enron a warrant (the
"Enron Warrant") to purchase a minimum of 2,544,347 shares of Common Stock (or
such number of shares of Common Stock equal to ten 10% of the outstanding Common
Stock on the date of exercise of the Enron Warrant) pursuant to the Warrant
Agreement dated as of December 4, 2000.

         7. The Unit Purchasers are purchasing, concurrently herewith, the Units
pursuant to the Note and Warrant Purchase Agreement.

         8. The Company and the Stockholders (as defined in Section 1 below)
desire to provide for certain arrangements with respect to (i) the registration
of shares of capital stock of the Company under the Securities Act of 1933, (ii)
rights of first refusal with respect to certain issuances of securities of the
Company and (iii) certain covenants of the Company.

         9. Section 5(f) of the Series A Investor Rights Agreement provides that
the Series A Investor Rights Agreement may be amended with the written consent
of the holders of 75% of the voting power of the Series A Stock, and the Common
Stock issued and issuable to Enron and the Common Stock issuable upon exercise
of the Enron Warrant then outstanding (giving effect to the conversion into
Common Stock of all securities convertible thereinto).

         10. Section 5.6 of the Series B Investor Rights Agreement provides that
the Series B Investor Rights Agreement may be amended with the written consent
of the holders of 75% of the voting power of the Series B Stock then outstanding
(giving effect to the conversion into Common Stock of all securities convertible
thereinto).

         11. The Company, BayCorp, Equiva, Enron, the Series A Stockholders and
the Series B Stockholders are the holders of at least 75% of the voting power of
the Series A Stock, the Series B Stock, the Common Stock issued and issuable to
Enron and the Common Stock issuable upon exercise of the Enron Warrant
outstanding (giving effect to the conversion into Common Stock of all securities
convertible thereinto) and of at least 75% of the voting power of the Series B
Stock outstanding (giving effect to the conversion into Common Stock of all
securities convertible thereinto), in each case immediately prior to the
issuance of the Units.


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         NOW, THEREFORE, in consideration of the mutual promises and covenants
contained in this Agreement, the parties hereto agree as follows:

         1.       Certain Definitions.

         As used in this Agreement, the following terms shall have the following
respective meanings:

         "Commission" means the Securities and Exchange Commission or any other
federal agency at the time administering the Securities Act.

          "Exchange Act" means the Securities Exchange Act of 1934, as amended,
or any successor federal statute, and the rules and regulations of the
Commission issued under such Act, as they each may, from time to time, be in
effect.

         "Initiating Holders" means the Stockholders initiating a request for
registration pursuant to Section 2.1(a) or 2.1(b), as the case may be.

         "Initial Public Offering" means the initial underwritten public
offering of shares of Common Stock pursuant to an effective Registration
Statement.

         "Junior Registrable Shares" means (i) the 10,000,000 shares of Common
Stock owned of record by BayCorp on the date hereof and (ii) the 4,814,815
shares of Common Stock owned of record by Equiva on the date hereof, in each
case such number of shares to be adjusted in the event of stock splits, stock
dividends, reclassifications, recapitalizations or similar events, in each case
such number of shares to be adjusted in the event of stock splits, stock
dividends, reclassifications, recapitalizations or similar events.

         "Other Holders" shall have the meaning set forth in Section 2.1(e).

         "Preferred Stockholders" means the Series A Stockholders, the Series B
Stockholders and the Series C Stockholders and their respective successors or
permitted assigns.

         "Prospectus" means the prospectus included in any Registration
Statement, as amended or supplemented by an amendment or prospectus supplement,
including post-effective amendments, and all material incorporated by reference
or deemed to be incorporated by reference in such Prospectus.

         "Registration Statement" means a registration statement filed by the
Company with the Commission for a public offering and sale of securities of the
Company (other than a registration statement on Form S-8 or Form S-4, or their
successors, or any other form for a similar limited purpose, or any registration
statement covering only securities proposed to be issued in exchange for
securities or assets of another corporation).

         "Registration Expenses" means the expenses described in Section 2.4.

         "Registrable Shares" means Senior Registrable Shares and Junior
Registrable Shares; provided, however, that shares of Common Stock which are
Registrable Shares shall cease to be Registrable Shares (i) upon any sale
pursuant to a Registration Statement or Rule 144 under the Securities Act, (ii)
at such time they become eligible for resale pursuant to Rule 144(k) under the
Securities Act or (iii) upon any sale in any manner to a person or entity which,
by virtue of Section 4 of this Agreement, is not entitled to the rights provided
by this Agreement. Wherever reference is made in this Agreement to a request or
consent of holders of a certain percentage of


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Registrable Shares, the determination of such percentage shall include shares of
Common Stock issuable upon conversion of the shares of Preferred Stock even if
such conversion has not been effected.

          "Securities Act" means the Securities Act of 1933, as amended, or any
successor federal statute, and the rules and regulations of the Commission
issued under such Act, as they each may, from time to time, be in effect.

         "Selling Stockholder" means any Stockholder owning Registrable Shares
included in a Registration Statement.

         "Senior Registrable Shares" means (i) the shares of Common Stock issued
or issuable upon conversion of the Preferred Stock, (ii) any shares of Common
Stock acquired or issuable upon the conversion or exercise of any other
securities acquired, by the Stockholders pursuant to Section 3 of this
Agreement, (iii) the shares of Common Stock issued or issuable to Enron, (iv)
the shares of Common Stock issued or issuable upon exercise of the Enron Warrant
once it becomes exercisable, (v) the shares of Common Stock issued or issuable
upon exercise of the Common Stock Warrants once they become exercisable, (vi)
the shares of Common Stock issued or issuable upon conversion of the Series C
Stock issued or issuable upon exercise of the Series C Stock Warrants once they
become exercisable and (vii) any other shares of Common Stock issued in respect
of shares referred to in the foregoing clauses (i), (ii), (iii), (iv), (v) and
(vi) (because of stock splits, stock dividends, reclassifications,
recapitalizations or similar events).

         "Series C Stockholder" means any holder of Series C Stock and any Unit
Purchaser or his, her or its respective successors or permitted assigns who
exercises any Series C Warrant.

         "Stockholders" means BayCorp, Enron and the Preferred Stockholders and
any persons or entities to whom the rights granted under this Agreement are
transferred by BayCorp, Enron or the Preferred Stockholders, their respective
successors or permitted assigns pursuant to Section 4 hereof.

         2.       Registration Rights.

                  2.1.     Required Registrations.

                  (a) Subject to the terms and conditions of this Agreement,
                  including without limitation Section 2.1(g), at any time after
                  the earlier of (x) the third anniversary date of the
                  Subsequent Closing (as defined in the Note and Warrant
                  Purchase Agreement) of the Units or (y) six months after the
                  closing of the Initial Public Offering, a Stockholder or
                  Stockholders holding in the aggregate at least 15% of the
                  Senior Registrable Shares then outstanding may request, in
                  writing, that the Company effect the registration on Form S-1
                  or Form S-2 (or any successor form) of Senior Registrable
                  Shares owned by such Stockholder or Stockholders having an
                  aggregate value of at least $10,000,000 (based on the then
                  current market price or fair value). Each such Stockholder's
                  request shall specify the number of Senior Registrable Shares
                  for which registration is sought by such Stockholder.

                  (b) Subject to the terms and conditions of this Agreement,
                  including without limitation Section 2.1(g), at any time after
                  the Company becomes eligible to file a Registration Statement
                  on Form S-3 (or any successor form relating to secondary


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                  offerings), a Stockholder or Stockholders holding in the
                  aggregate at least 15% of the Senior Registrable Shares then
                  outstanding or holding any Junior Registrable Shares may
                  request, in writing, that the Company effect the registration
                  on Form S-3 (or such successor form) of Registrable Shares
                  having an aggregate value of at least $5,000,000 (based on the
                  then current public market price).

                  (c) Upon receipt of any request for registration from any
                  stockholder having registration rights pursuant to this
                  Agreement or any other agreement, the Company shall promptly
                  give written notice of such proposed registration to all other
                  Stockholders. Such Stockholders shall have the right, by
                  giving written notice to the Company within 20 days after the
                  Company provides its notice, to elect to have included in such
                  registration such of their Registrable Shares as such
                  Stockholders may request in such notice of election, subject,
                  in the case of an underwritten offering, to the approval of
                  the managing underwriter as provided in Section 2.1(e) below.
                  Thereupon, the Company shall, as expeditiously as possible,
                  use commercially reasonable efforts to effect the registration
                  on an appropriate registration form of all Registrable Shares
                  which the Company has been requested to so register; provided,
                  however, that in the case of a registration requested under
                  Section 2.1(b), the Company will only be obligated to effect
                  such registration on Form S-3 (or any successor form).

                  (d) If the Initiating Holders intend to distribute the
                  Registrable Shares covered by their request by means of an
                  underwriting, they shall so advise the Company as a part of
                  their request made pursuant to Section 2.1(a) or (b), as the
                  case may be, and the Company shall include such information in
                  its written notice referred to in Section 2.1(c). The right of
                  any other Stockholder to include its Registrable Shares in
                  such registration pursuant to Section 2.1(a) or (b), as the
                  case may be, shall be conditioned upon such other
                  Stockholder's participation in such underwriting on the terms
                  set forth herein.

                  (e) If the Company desires that any officers or directors of
                  the Company holding securities of the Company be included in
                  any registration for an underwritten offering requested
                  pursuant to Section 2.1(d) or if other holders of securities
                  of the Company who are entitled, by contract with the Company,
                  to have securities included in such a registration (the "Other
                  Holders") request such inclusion, the Company may include the
                  securities of such officers, directors and Other Holders in
                  such registration and underwriting on the terms set forth
                  herein. The Company shall (together with all Stockholders,
                  officers, directors and Other Holders proposing to distribute
                  their securities through such underwriting) enter into an
                  underwriting agreement in customary form (including, without
                  limitation, customary indemnification and contribution
                  provisions on the part of the Company) with the managing
                  underwriter; provided that such underwriting agreement shall
                  not provide for indemnification or contribution obligations on
                  the part of Stockholders that are materially greater than the
                  obligations of the Stockholders under Section 2.5; provided
                  further, that the Company shall use commercially reasonable
                  efforts to negotiate with the underwriters so that the
                  underwriting agreement will not require the Stockholders to
                  make any


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                  representation or warranty other than in connection with
                  information described in Section 2.7. Notwithstanding any
                  other provision of this Section 2.1(e), if the managing
                  underwriter advises the Company that the inclusion of all
                  shares requested to be registered would adversely affect the
                  offering or could not reasonably be sold within the price
                  range acceptable to the Initiating Holders owning a majority
                  of the securities requested to be included by the Initiating
                  Holders, then first the securities of the Company held by
                  officers or directors of the Company (other than Registrable
                  Shares), and second the securities held by Other Holders
                  (other than Registrable Shares) and third Junior Registrable
                  Shares in the case of an offering initiated by holders of
                  Senior Registrable Shares and Senior Registrable Shares in the
                  case of an offering initiated by holders of Junior Registrable
                  Shares shall be excluded from such registration and
                  underwriting in that order and to the extent deemed advisable
                  by the managing underwriter, and if a further limitation of
                  the number of shares is required, the number of shares that
                  may be included in such registration and underwriting shall be
                  allocated first among all holders of Senior Registrable Shares
                  requesting registration in proportion, as nearly as
                  practicable, to the respective number of Senior Registrable
                  Shares held by them at the time of the request for
                  registration made by the Initiating Holders pursuant to
                  Section 2.1(a) or (b), as the case may be, and second among
                  all holders of Junior Registrable Shares requesting
                  registration in proportion, as nearly as practicable, to the
                  respective number of Junior Registrable Shares held by them at
                  the time of the request for registration made by the
                  Initiating Holders pursuant to Section 2.1(a) or (b), as the
                  case may be. If any holder of Registrable Shares, officer,
                  director or Other Holder who has requested inclusion in such
                  registration as provided above disapproves of the terms of the
                  underwriting, such person may elect to withdraw therefrom by
                  written notice to the Company, and the securities so withdrawn
                  shall also be withdrawn from registration. If the managing
                  underwriter has not limited the number of Registrable Shares
                  or other securities to be underwritten, the Company may
                  include securities for its own account in such registration if
                  (i) the managing underwriter so agrees, (ii) the number of
                  Registrable Shares and other securities which would otherwise
                  have been included in such registration and underwriting will
                  not thereby be limited and (iii) the inclusion of the
                  Company's securities will not, in the opinion of the managing
                  underwriters, adversely affect the ability of the holders of
                  Registrable Shares to be included in the offering to sell such
                  Registrable Shares within the price range acceptable to the
                  Initiating Holders holding a majority of the securities
                  requested to be included by the Initiating Holders.

                  (f) The Company shall have the right to select the managing
                  underwriter(s) for any underwritten offering requested
                  pursuant to Section 2.1(a) or (b), subject to the approval of
                  a majority of the Initiating Holders, which approval will not
                  be unreasonably withheld or delayed.

                  (g) The Company shall not be required to file or cause a
                  Registration Statement to be declared effective for (i) more
                  than one registration pursuant to Section 2.1(a) during any
                  12-month period, (ii) more than two registrations


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                  pursuant to Section 2.1(a) during the term of this Agreement,
                  (iii) more than seven registrations pursuant to Section 2.1(b)
                  during the term of this Agreement of which two may be
                  initiated by BayCorp, one may be initiated by Equiva as to its
                  Junior Registrable Shares, one may be initiated by Elliott
                  Associates, L.P. ("Elliott"), one may be initiated by Omega
                  Advisors, Inc. ("Omega") and two may be initiated by holders
                  of Senior Registrable Shares other than Elliott and Omega. In
                  addition, during the one year period immediately following the
                  Initial Public Offering, the Company shall not be required to
                  effect any registration (other than a registration on Form S-3
                  or any successor form relating to non-underwritten secondary
                  offerings) within six months after the effective date of any
                  other Registration Statement of the Company. After the first
                  anniversary of the Initial Public Offering, the Company shall
                  not be required to effect any registration (other than a
                  registration on Form S-3 or any successor form relating to
                  non-underwritten secondary offerings) within three months
                  after the effective date of any other Registration Statement
                  of the Company. For purposes of this Section 2.1(g), a
                  Registration Statement shall not be counted until such time as
                  such Registration Statement has been declared effective by the
                  Commission (unless the Initiating Holders withdraw their
                  request for such registration (other than as a result of
                  adverse information concerning the business or financial
                  condition of the Company which is made known to the
                  Stockholders after the date on which such registration was
                  requested) and elect not to pay the Registration Expenses
                  therefor pursuant to Section 2.4). In addition, and
                  notwithstanding the foregoing provisions of this Section
                  2.1(g), in the event that, in connection with any registration
                  pursuant to 2.1(a) or 2.1(b), if (x) the underwriters insist,
                  despite commercially reasonable efforts by the Company to the
                  contrary, that as a condition to the participation of Equiva
                  in the offering Equiva make representations and warranties
                  other than representations and warranties in connection with
                  information described in Section 2.7 and (y) Equiva elects not
                  to participate in such registration as a result of such
                  underwriters' action, then Equiva by itself shall be entitled
                  to initiate one additional registration pursuant to Section
                  2.1(a) or 2.1(b), as applicable, regardless of the percentage
                  of outstanding shares of Senior Registrable Shares or Junior
                  Registrable Shares then owned at such time by Equiva or the
                  aggregate value of the Senior Registrable Shares or Junior
                  Registrable Shares to be registered (by Equiva or others), and
                  the number of registrations that the Company is required to
                  effect pursuant to clause (ii) or (iii), as the cases may be,
                  shall be increased by one.

                  (h) If at the time of any request to register Registrable
                  Shares by Initiating Holders pursuant to this Section 2.1, the
                  Company is engaged or has plans to engage in a registered
                  public offering or is engaged in any other activity which, in
                  the good faith determination of the Company's Board of
                  Directors, would be adversely affected by the requested
                  registration, then the Company may at its option direct that
                  such request be delayed for a period not in excess of 50 days
                  from the date of such request. During any such delay period,
                  the Company shall continue to prepare a proposed Registration
                  Statement, but may delay filing such Registration Statement
                  pursuant to this Section 2.1(h). The Company's right to


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                  delay a request may not be exercised by the Company more than
                  twice in any 12-month period.

                  2.2.     Incidental Registration.

                  (a) Whenever the Company proposes to file a Registration
                  Statement (other than a Registration Statement filed pursuant
                  to Section 2.1 or a Registration Statement covering shares to
                  be sold solely for the account of Other Holders) at any time
                  and from time to time, it will, prior to such filing, give
                  written notice to all Stockholders of its intention to do so;
                  provided, that no such notice need be given if no Registrable
                  Shares are to be included therein as a result of a
                  determination of the managing underwriter pursuant to Section
                  2.2(b). Upon the written request of a Stockholder or
                  Stockholders given within 20 days after the Company provides
                  such notice (which request shall state the intended method of
                  disposition of such Registrable Shares), the Company shall use
                  commercially reasonable efforts to cause all Registrable
                  Shares which the Company has been requested by such
                  Stockholder or Stockholders to register to be registered under
                  the Securities Act to the extent necessary to permit their
                  sale or other disposition in accordance with the intended
                  methods of distribution specified in the request of such
                  Stockholder or Stockholders; provided that the Company shall
                  have the right to postpone or withdraw any registration
                  effected pursuant to this Section 2.2 without obligation to
                  any Stockholder.

                  (b) If the registration for which the Company gives notice
                  pursuant to Section 2.2(a) is a registered public offering
                  involving an underwriting, the Company shall so advise the
                  Stockholders as a part of the written notice given pursuant to
                  Section 2.2(a). In such event, the right of any Stockholder to
                  include its Registrable Shares in such registration pursuant
                  to Section 2.2 shall be conditioned upon (i) such
                  Stockholder's participation in such underwriting on the terms
                  set forth herein and (ii) the Company's right to first
                  register securities under Section 2.2(a) in preference over
                  the Stockholders' incidental registration rights pursuant to
                  this Section 2.2. All Stockholders proposing to distribute
                  their securities through such underwriting shall enter into an
                  underwriting agreement in customary form with the underwriter
                  or underwriters selected for the underwriting by the Company;
                  provided that such underwriting agreement shall not provide
                  for indemnification or contribution obligations on the part of
                  Stockholders that are greater than the obligations of the
                  Stockholders under Section 2.5; provided further, that the
                  Company shall use commercially reasonable efforts to negotiate
                  with the underwriters so that the underwriting agreement will
                  not require the Stockholders to make any representation or
                  warranty other than in connection with information described
                  in Section 2.7. Notwithstanding any other provision of this
                  Section 2.2, if the managing underwriter determines that the
                  inclusion of all shares requested to be registered would
                  adversely affect the offering, the Company may limit the
                  number of Registrable Shares to be included in the
                  registration and underwriting. The Company shall so advise all
                  holders of Registrable Shares requesting registration; and the
                  number of shares that are entitled to be included in the
                  registration and underwriting shall be allocated in


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                  the following manner. The securities of the Company held by
                  holders other than Stockholders and Other Holders shall be
                  excluded from such registration and underwriting to the extent
                  deemed advisable by the managing underwriter, and, if a
                  further limitation on the number of shares is required, the
                  number of shares that may be included in such registration and
                  underwriting shall be allocated among all Stockholders and
                  Other Holders requesting registration in proportion, as nearly
                  as practicable, to the respective number of shares of Common
                  Stock (on an as-converted basis) which they held at the time
                  the Company gives the notice specified in Section 2.2(a). If
                  any Stockholder or Other Holder would thus be entitled to
                  include more securities than such holder requested to be
                  registered, the excess shall be allocated among other
                  requesting Stockholders and Other Holders pro rata in the
                  manner described in the preceding sentence. If any holder of
                  Registrable Shares or any officer, director or Other Holder
                  disapproves of the terms of any such underwriting, such person
                  may elect to withdraw therefrom by written notice to the
                  Company, and any Registrable Shares or other securities
                  excluded or withdrawn from such underwriting shall be
                  withdrawn from such registration. Notwithstanding any other
                  provision of this Section 2.2, the Company shall not be
                  required to exclude or reduce in amount any shares of Common
                  Stock proposed to be sold by the Company in order to
                  facilitate the registration of Registrable Shares or any other
                  shares of Common Stock held by Company stockholders.

                  2.3.     Registration Procedures.

                  (a) If and whenever the Company is required by the provisions
                  of this Agreement to use all commercially reasonable efforts
                  to effect the registration of Registrable Securities under the
                  Securities Act, the Company will, as expeditiously as
                  practicable, do the following:

                           (i) prepare and file with the Commission a
                           Registration Statement with respect to such
                           Registrable Shares and use all commercially
                           reasonable efforts to cause that Registration
                           Statement to become effective as soon as practicable
                           and endeavor to cause that Registration Statement to
                           remain effective until the earlier of (i) the date
                           when all Registrable Shares covered thereby have been
                           sold or (ii) 90 days from the effective date of the
                           Registration Statement; provided that before filing a
                           Registration Statement or Prospectus or any
                           amendments or supplements thereto, the Company shall
                           furnish to one counsel, selected by the holders of
                           Registrable Shares covered by the Registration
                           Statement as a group, a copy of all such documents
                           proposed to be filed;

                           (ii) prepare and file with the Commission any
                           amendments and supplements to the Registration
                           Statement and the prospectus included in the
                           Registration Statement as may be necessary to comply
                           with the provisions of the Securities Act (including
                           the anti-fraud provisions thereof) and to keep the
                           Registration Statement effective for 90 days from


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<PAGE>
                           the effective date or such lesser period until all
                           such Registrable Shares are sold;

                           (iii) furnish to each Selling Stockholder such
                           reasonable numbers of copies of the Prospectus,
                           including any preliminary Prospectus or Prospectus
                           filed pursuant to Rule 424 under the Securities Act,
                           in conformity with the requirements of the Securities
                           Act, and such other documents as such Selling
                           Stockholder may reasonably request in order to
                           facilitate the public sale or other disposition of
                           the Registrable Shares owned by such Selling
                           Stockholder;

                           (iv) use all commercially reasonable efforts to
                           register or qualify the Registrable Shares covered by
                           the Registration Statement under the securities or
                           Blue Sky laws of such states as the Selling
                           Stockholders shall reasonably request, and do any and
                           all other acts and things that may be necessary or
                           desirable to enable the Selling Stockholders to
                           consummate the public sale or other disposition in
                           such states of the Registrable Shares owned by the
                           Selling Stockholders; provided, however, that the
                           Company shall not be required in connection with this
                           paragraph (iv) to qualify as a foreign corporation or
                           execute a general consent to service of process in
                           any jurisdiction;

                           (v) cause all such Registrable Shares to be listed,
                           prior to the date of the first sale of such
                           Registrable Shares pursuant to the registration, on
                           each securities exchange or automated quotation
                           system on which similar securities issued by the
                           Company are then listed; and if not then so listed,
                           to use commercially reasonable efforts to cause all
                           such Registrable Shares to be listed, prior to the
                           date of the first sale of such Registrable Shares
                           pursuant to the registration and to the extent the
                           Company meets the securities exchange or automated
                           quotation system's listing requirements, on such
                           exchange or system; provided that if such listing is
                           not commercially practicable, then as "pink sheet" or
                           similar securities, if commercially practicable;
                           provided further that if no such listing is
                           commercially practicable, the Company shall have no
                           obligations under this clause (v);

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

                           (vii) promptly make available for inspection by each
                           Selling Stockholder, any managing underwriter
                           participating in any disposition pursuant to such
                           Registration Statement, and any one attorney or any
                           one accountant retained by any such underwriter or
                           selected by the Selling Stockholders as a group, all
                           financial and other records, pertinent corporate
                           documents and properties of the Company and cause the
                           Company's officers, directors, employees and
                           independent accountants to


                                       10
<PAGE>
                           supply all information reasonably requested by any
                           such seller, underwriter, attorney, accountant or
                           agent in connection with such Registration Statement;

                           (viii) notify each Selling Stockholder, promptly
                           after it shall receive notice thereof, of the time
                           when such Registration Statement has become effective
                           or a supplement to any Prospectus forming a part of
                           such Registration Statement has been filed;

                           (ix) promptly following the effectiveness of such
                           Registration Statement, notify each seller of such
                           Registrable Shares of any request by the Commission
                           for the amending or supplementing of such
                           Registration Statement or Prospectus;

                           (x) notify each Selling Stockholder, at any time when
                           a Prospectus relating thereto is required to be
                           delivered under the Securities Act, when the Company
                           learns of the happening of any event as a result of
                           which the Prospectus included in such Registration
                           Statement contains an untrue statement of a material
                           fact or omits any fact necessary to make the
                           statements therein not materially misleading, and, at
                           the request of any such seller, the Company will
                           promptly prepare (and, when completed, give notice to
                           each Selling Stockholder) a supplement or amendment
                           to such Prospectus so that, as thereafter delivered
                           to the purchasers of the Registrable Shares, such
                           Prospectus will not contain an untrue statement of a
                           material fact or omit to state any fact necessary to
                           make the statements therein not materially
                           misleading; provided that upon such notification by
                           the Company, each Selling Stockholder will not offer
                           or sell such Registrable Securities until the Company
                           has notified such seller that it has prepared a
                           supplement or amendment to such Prospectus and
                           delivered copies of such supplement or amendment to
                           such Selling Stockholder;

                           (xi) enter into all such customary agreements
                           (including underwriting agreements in customary form)
                           and take all such other actions as any Selling
                           Stockholder or the underwriters, if any, reasonably
                           request in order to expedite or facilitate the
                           disposition of such Registrable Shares;

                           (xii) in the event of the issuance of any stop order
                           suspending the effectiveness of a Registration
                           Statement, or of any order suspending or preventing
                           the use of any related Prospectus or suspending the
                           qualification of any Registrable Shares included in
                           such Registration Statement for sale in any
                           jurisdiction, the Company will use commercially
                           reasonable efforts promptly to obtain the withdrawal
                           of such order;

                           (xiii) use its commercially reasonable efforts to
                           obtain:


                                       11
<PAGE>
                                    (A) at the time of effectiveness of each
                                    registration, a "comfort letter" from the
                                    Company's independent certified public
                                    accountants covering such matters of the
                                    type customarily covered by "cold comfort
                                    letters" as the underwriters reasonably
                                    request; and

                                    (B) at the time of any underwritten sale
                                    pursuant to a Registration Statement, a
                                    "bring-down comfort letter," dated as of the
                                    date of such sale, from the Company's
                                    independent certified public accountants
                                    covering such matters of the type
                                    customarily covered by comfort letters as
                                    the underwriters reasonably request;

                           (xiv) use its commercially reasonable efforts to
                           obtain, at the time of effectiveness of each
                           registration described in Section 2.2 and at the time
                           of any sale pursuant to each registration, an opinion
                           or opinions, from counsel to the Company, as
                           reasonably requested by the Selling Stockholders
                           regarding matters of the type customarily included in
                           such opinions;

                           (xv) make generally available to its stockholders as
                           soon as practicable, but not later than 45 days after
                           the end of the 12-month period beginning at the end
                           of the fiscal quarter of the Company during which the
                           effective date of the Registration Statement occurs
                           (or 90 days if such 12-month period coincides with
                           the Company's fiscal year), an earnings statement
                           (which need not be audited) of the Company, covering
                           such 12-month period which shall satisfy the
                           provisions of Section 11(a) of the Securities Act or
                           Rule 158 under the Securities Act;

                           (xvi) if the Company has delivered a Prospectus to
                           the Selling Stockholders and after having done so the
                           Prospectus is amended to comply with the requirements
                           of the Securities Act, the Company shall promptly
                           notify the Selling Stockholders and, if requested,
                           the Selling Stockholders shall immediately cease
                           making offers of Registrable Shares and return all
                           Prospectuses to the Company. The Company shall
                           promptly provide the Selling Stockholders with
                           revised Prospectuses and, following receipt of the
                           revised Prospectuses, the Selling Stockholders shall
                           be free to resume making offers of the Registrable
                           Shares; and

                           (xvii) in the event that, in the judgment of the
                           Company, it is advisable to suspend use of a
                           Prospectus included in a Registration Statement due
                           to pending material developments or other events that
                           have not yet been publicly disclosed and as to which
                           the Company believes public disclosure would be
                           detrimental to the Company, the Company shall notify
                           all Selling Stockholders to such effect, and, upon
                           receipt of such notice, each such Selling Stockholder
                           shall immediately discontinue any sales of
                           Registrable Shares pursuant to such Registration
                           Statement until such Selling Stockholder has received
                           copies of a supplemented or amended


                                       12
<PAGE>
                           Prospectus or until such Selling Stockholder is
                           advised in writing by the Company that the then
                           current Prospectus may be used and has received
                           copies of any additional or supplemental filings that
                           are incorporated or deemed incorporated by reference
                           in such Prospectus. Notwithstanding anything to the
                           contrary herein, the Company shall not exercise its
                           rights under this Section 2.3 to suspend sales of
                           Registrable Shares for a period in excess of 50 days
                           more than twice in any 12-month period.

                  2.4. Allocation of Expenses. The Company will pay all
         Registration Expenses for all registrations under this Agreement;
         provided, however, that if a registration under Section 2.1 is
         withdrawn at the request of the Initiating Holders (other than as a
         result of adverse information concerning the business or financial
         condition of the Company which is made known to the Stockholders after
         the date on which such registration was requested) and if the
         Initiating Holders elect not to have such registration counted as a
         registration requested under Section 2.1, the requesting Stockholders
         shall pay the Registration Expenses of such registration pro rata in
         accordance with the number of their Registrable Shares included in such
         registration. For purposes of this Section, the term "Registration
         Expenses" shall mean all expenses incurred by the Company in performing
         or complying with this Agreement, including, without limitation, all
         registration and filing fees, exchange or quotation listing fees,
         printing expenses, messenger and delivery fees, fees and expenses of
         counsel for the Company, state Blue Sky fees and expenses and the fees
         and expenses of any certified public accountants of the Company and
         other third parties specifically retained by the Company, but excluding
         underwriting discounts, selling commissions and the fees and expenses
         of Selling Stockholders' own counsel.

                  2.5.     Indemnification and Contribution.

                  (a) In the event of any registration of any of the Registrable
                  Shares under the Securities Act pursuant to this Agreement,
                  the Company will indemnify and hold harmless each Selling
                  Stockholder, its directors, officers and shareholders, each
                  underwriter of such Registrable Shares and each other person,
                  if any, who controls such Selling Stockholder or underwriter
                  within the meaning of the Securities Act or the Exchange Act
                  against any losses, claims, damages or liabilities, joint or
                  several, to which such Selling Stockholder, underwriter or
                  controlling person may become subject under the Securities
                  Act, the Exchange Act, state securities or Blue Sky laws or
                  otherwise, insofar as such losses, claims, damages or
                  liabilities (or actions in respect thereof) arise out of or
                  are based upon any untrue statement or alleged untrue
                  statement of any material fact contained in any Registration
                  Statement under which such Registrable Shares were registered
                  under the Securities Act, any preliminary prospectus or final
                  prospectus contained in the Registration Statement, or any
                  amendment or supplement to such Registration Statement, or
                  arise out of or are based upon the omission or alleged
                  omission to state a material fact required to be stated
                  therein or necessary to make the statements therein not
                  misleading; and the Company will reimburse such Selling
                  Stockholder, underwriter and each such controlling person for
                  any legal or any other expenses reasonably incurred by such
                  Selling Stockholder, underwriter or controlling person in
                  connection with investigating or defending any such loss,


                                       13
<PAGE>
                  claim, damage, liability or action; provided, however, that
                  the Company will not be liable in any such case to the extent,
                  that any such loss, claim, damage or liability arises out of
                  or is based upon any untrue statement or omission made in such
                  Registration Statement, preliminary prospectus or prospectus,
                  or any such amendment or supplement, in reliance upon and in
                  conformity with information furnished to the Company, in
                  writing, by or on behalf of such Selling Stockholder,
                  underwriter or controlling person specifically for use in the
                  preparation thereof; further provided, however, that the
                  Company shall be liable and shall provide indemnification
                  under this Section 2.5(a) to the extent that (after such
                  Selling Stockholder, underwriter or controlling person
                  furnishes to the Company, in writing, information that
                  corrects any previous untrue statement or alleged untrue
                  statement of any material fact contained in any Registration
                  Statement under which such Registrable Shares were registered
                  under the Securities Act, any preliminary prospectus or final
                  prospectus contained in the Registration Statement, or any
                  amendment or supplement to such Registration Statement, or
                  arise out of or are based upon the previous omission or
                  alleged omission to state a material fact required to be
                  stated therein or necessary to make the statements therein not
                  misleading) the Company fails to prepare and deliver to
                  purchasers of the Company's securities pursuant to such
                  registration a final prospectus that corrects such previous
                  untrue statement or alleged untrue statement of material fact
                  or such previous omission or alleged omission to state a
                  material fact and such correction is in conformity with
                  information furnished to the Company, in writing, by or on
                  behalf of such Selling Stockholder, underwriter or controlling
                  person specifically for use in the preparation thereof.

                  (b) In the event of any registration of any of the Registrable
                  Shares under the Securities Act pursuant to this Agreement,
                  each Selling Stockholder, severally and not jointly, will
                  indemnify and hold harmless the Company, each of its directors
                  and officers and each underwriter (if any) and each person, if
                  any, who controls the Company or any such underwriter within
                  the meaning of the Securities Act or the Exchange Act, against
                  any losses, claims, damages or liabilities, joint or several,
                  to which the Company, such directors and officers, underwriter
                  or controlling person may become subject under the Securities
                  Act, Exchange Act, state securities or Blue Sky laws or
                  otherwise, insofar as such losses, claims, damages or
                  liabilities (or actions in respect thereof) arise out of or
                  are based upon any untrue statement or alleged untrue
                  statement of a material fact contained in any Registration
                  Statement under which such Registrable Shares were registered
                  under the Securities Act, any preliminary prospectus or final
                  prospectus contained in the Registration Statement, or any
                  amendment or supplement to the Registration Statement, or
                  arise out of or are based upon any omission or alleged
                  omission to state a material fact required to be stated
                  therein or necessary to make the statements therein not
                  misleading, but only if and to the extent the statement or
                  omission was made in reliance upon and in conformity with
                  information relating to such Selling Stockholder furnished in
                  writing to the Company by or on behalf of such Selling
                  Stockholder indicating that it was provided specifically for
                  use in such Registration Statement, prospectus, amendment or
                  supplement; provided, however, that the obligations of a
                  Selling


                                       14
<PAGE>
                  Stockholder hereunder shall be limited to an amount equal to
                  the net proceeds to such Selling Stockholder of Registrable
                  Shares sold in connection with such registration.

                  (c) Each party entitled to indemnification under this Section
                  (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 litigation, shall be approved by the
                  Indemnified Party (whose approval shall not be unreasonably
                  withheld); 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 except to the extent that the Indemnifying Party is
                  adversely affected by such failure. The Indemnified Party may
                  participate in such defense at such party's expense; provided,
                  however, that the Indemnifying Party shall pay such expense if
                  representation of such Indemnified Party by the counsel
                  retained by the Indemnifying Party would be inappropriate due
                  to actual or potential differing interests between the
                  Indemnified Party and any other party represented by such
                  counsel in such proceeding; provided further that in no event
                  shall the Indemnifying Party be required to pay the expenses
                  of more than one law firm per jurisdiction as counsel for the
                  Indemnified Party. The Indemnifying Party also shall be
                  responsible for the expenses of such defense if the
                  Indemnifying Party does not elect to assume such defense. No
                  Indemnifying Party, in the defense of any such claim or
                  litigation shall, except with the consent of each Indemnified
                  Party, 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
                  of such claim or litigation, and no Indemnified Party shall
                  consent to entry of any judgment or settle such claim or
                  litigation without the prior written consent of the
                  Indemnifying Party, which consent shall not be unreasonably
                  withheld.

                  (d) In order to provide for just and equitable contribution in
                  circumstances in which the indemnification provided for in
                  this Section 2.5 is due in accordance with its terms but for
                  any reason is held to be unavailable to an Indemnified Party
                  in respect to any losses, claims, damages and liabilities
                  referred to herein, then the Indemnifying Party shall, in lieu
                  of indemnifying such Indemnified Party, contribute to the
                  amount paid or payable by such Indemnified Party as a result
                  of such losses, claims, damages or liabilities to which such
                  party may be subject in such proportion as is appropriate to
                  reflect the relative fault of the Company on the one hand and
                  the Selling Stockholders on the other in connection with the
                  statements or omissions which resulted in such losses, claims,
                  damages or liabilities, as well as any other relevant
                  equitable considerations. The relative fault of the Company
                  and the Selling Stockholders shall be determined by reference
                  to, among other things, whether the untrue or alleged untrue
                  statement of material fact related to information supplied by
                  the Company or the Selling


                                       15
<PAGE>
                  Stockholders and the parties' relative intent, knowledge,
                  access to information and opportunity to correct or prevent
                  such statement or omission. The Company and the Selling
                  Stockholders agree that it would not be just and equitable if
                  contribution pursuant to this Section 2.5 were determined by
                  pro rata allocation or by any other method of allocation which
                  does not take account of the equitable considerations referred
                  to above. Notwithstanding the provisions of this paragraph of
                  Section 2.5, (i) in no case shall any one Selling Stockholder
                  be liable or responsible for any amount in excess of the net
                  proceeds received by such Selling Stockholder from the
                  offering of Registrable Shares and (ii) the Company shall be
                  liable and responsible for any amount in excess of such
                  proceeds; provided, however, that no person guilty of
                  fraudulent misrepresentation (within the meaning of Section
                  11(f) of the Securities Act) shall be entitled to contribution
                  from any person who was not guilty of such fraudulent
                  misrepresentation. Any party entitled to contribution will,
                  promptly after receipt of notice of commencement of any
                  action, suit or proceeding against such party in respect of
                  which a claim for contribution may be made against another
                  party or parties under this Section, notify such party or
                  parties from whom contribution may be sought, but the omission
                  so to notify such party or parties from whom contribution may
                  be sought shall not relieve such party from any other
                  obligation it or they may have thereunder or otherwise under
                  this Section. No party shall be liable for contribution with
                  respect to any action, suit, proceeding or claim settled
                  without its prior written consent, which consent shall not be
                  unreasonably withheld.

                  2.6. Other Matters with Respect to Underwritten Offerings. In
         the event that Registrable Shares are sold pursuant to a Registration
         Statement in an underwritten offering pursuant to Section 2.1, the
         Company agrees to (a) enter into an underwriting agreement containing
         customary representations and warranties with respect to the business
         and operations of the Company and customary covenants and agreements to
         be performed by the Company, including without limitation customary
         provisions with respect to indemnification by the Company of the
         underwriters of such offering; (b) cause its legal counsel to render
         customary opinions to the underwriters with respect to the Registration
         Statement; and (c) cause its independent public accounting firm to
         issue customary "cold comfort letters" to the underwriters with respect
         to the Registration Statement.

                  In any underwritten offering in which shares of the Preferred
         Stockholders are to be included, if the managing underwriter requests a
         limitation in the number of such shares to be included therein, then
         any such reduction shall be borne ratably by the Preferred Stockholders
         in proportion to the number of shares held by each that carry
         registration rights.

                  2.7. Information by Holder. Each holder of Registrable Shares
         included in any registration shall furnish to the Company such
         information regarding such holder and the distribution proposed by such
         holder as the Company may reasonably request in writing and as shall be
         required in connection with any registration, qualification or
         compliance referred to in this Agreement.


                                       16
<PAGE>
                  2.8. "Stand-Off" Agreement; Confidentiality of Notices. Each
         Stockholder, if requested by the Company or the managing underwriter of
         an underwritten public offering by the Company of Common Stock, shall
         not sell or otherwise transfer or dispose of any Registrable Shares or
         other securities of the Company held by such Stockholder for a period
         of 180 days following the effective date of a Registration Statement;
         provided that such 180 day period shall be reduced to 120 days for
         underwritten public offerings other than the Company's Initial Public
         Offering and shall apply only if all of the Company's directors and
         executive officers are subject to substantially equivalent restrictions
         on sales, transfers and other dispositions of securities of the Company
         held by such person or entity; further provided that in all cases, the
         Company shall also be subject to substantially equivalent restrictions
         on sales, transfers and other dispositions of securities of the Company
         for such 180-day or 120-day periods, as the case may be.

                  The Company may impose stop-transfer instructions with respect
         to the Registrable Shares or other securities subject to the foregoing
         restriction until the end of such 180-day or 120-day periods, as the
         case may be.

                  Any Stockholder receiving any written notice from the Company
         regarding the Company's plans to file a Registration Statement shall
         treat such notice confidentially and shall not disclose such
         information to any person other than as necessary to exercise its
         rights under this Agreement.

                  2.9. Limitations on Subsequent Registration Rights. The
         Company shall not, without the prior written consent of Stockholders
         holding at least 85% of the Registrable Shares then held by all
         Stockholders, enter into any agreement (other than this Agreement) with
         any holder or prospective holder of any securities of the Company which
         grants such holder or prospective holder rights to demand a
         registration of securities of the Company or include securities of the
         Company in any Registration Statement, unless such rights are not more
         favorable than the rights granted to the Stockholders under this
         Agreement.

                  2.10. Rule 144 Requirements. After the earliest of (i) the
         closing of the sale of securities of the Company pursuant to a
         Registration Statement, (ii) the registration by the Company of a class
         of securities under Section 12 of the Exchange Act, or (iii) the
         issuance by the Company of an offering circular pursuant to Regulation
         A under the Securities Act, the Company agrees to:

                  (a) use all commercially reasonable efforts to make and keep
                  current public information about the Company available, as
                  those terms are understood and defined in Rule 144;

                  (b) use all commercially reasonable efforts to file with the
                  Commission in a timely manner all reports and other documents
                  required of the Company under the Securities Act and the
                  Exchange Act (at any time after it has become subject to such
                  reporting requirements); and


                                       17
<PAGE>
                  (c) furnish to any holder of Registrable Shares upon request
                  (i) 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 (at any time after it has
                  become subject to such reporting requirements), (ii) a copy of
                  the most recent annual or quarterly report of the Company and
                  (iii) such other reports and documents of the Company as such
                  holder may reasonably request to avail itself of any similar
                  rule or regulation of the Commission allowing it to sell any
                  such securities without registration.

                  2.11. Termination. All of the Company's obligations to
         register Registrable Shares under Sections 2.1 and 2.2 of this
         Agreement shall terminate ten years after the closing of the Initial
         Public Offering.

         3.       Right Of First Refusal.

                  3.1.     Rights of Stockholders.

                  (a) The Company shall not issue, sell or exchange, agree to
                  issue, sell or exchange, or reserve or set aside for issuance,
                  sale or exchange, (i) any shares of its Common Stock, (ii) any
                  other equity securities of the Company, including, without
                  limitation, shares of preferred stock, (iii) any option,
                  warrant or other right to subscribe for, purchase or otherwise
                  acquire any equity securities of the Company or any securities
                  exercisable for or convertible into any such securities or
                  (iv) any debt securities convertible into capital stock of the
                  Company (collectively, the "Offered Securities"), unless in
                  each such case the Company shall have first complied with this
                  Section 3.1. The Company shall deliver to each Stockholder a
                  written notice of any proposed or intended issuance, sale or
                  exchange of Offered Securities (the "Offer"), which Offer
                  shall (i) identify and describe the Offered Securities, (ii)
                  describe the price and other terms upon which they are to be
                  issued, sold or exchanged, and the number or amount of the
                  Offered Securities to be issued, sold or exchanged, (iii)
                  identify the persons or entities (if known) to which or with
                  which the Offered Securities are to be offered, issued, sold
                  or exchanged and (iv) offer to issue and sell to or exchange
                  with such Stockholder (A) a pro rata portion of the Offered
                  Securities determined by dividing the aggregate number of
                  shares of Common Stock then held by such Stockholder (giving
                  effect to the full conversion or exercise of all shares of
                  convertible preferred securities and warrants then held by
                  such Stockholder) by the total number of shares of Common
                  Stock then outstanding (giving effect to the full conversion
                  or exercise of all outstanding shares of convertible preferred
                  securities and warrants held by all Stockholders) (the "Basic
                  Amount"), and (B) in the event that all of the Offered
                  Securities are not subscribed for, all or any portion of the
                  Offered Securities that remain (the "Undersubscription
                  Amount").

                  (b) To accept an Offer, in whole or in part, a Stockholder
                  must deliver a written notice to the Company prior to 20 days
                  after the date of delivery of the Offer, setting forth the
                  portion of the Stockholder's Basic Amount that such
                  Stockholder elects to purchase and, if such Stockholder shall
                  elect to purchase all


                                       18
<PAGE>
                  of its Basic Amount, the Undersubscription Amount (if any)
                  that such Stockholder elects to purchase (the "Notice of
                  Acceptance"). If the Basic Amounts subscribed for by all
                  Stockholders are less than the number or amount of the Offered
                  Securities, then each Stockholder who has offered to purchase
                  a portion of the Undersubscription Amount in its Notice of
                  Acceptance shall be entitled to purchase, in addition to the
                  Basic Amounts subscribed for, the Undersubscription Amount it
                  has subscribed for; provided, however, that if the
                  Undersubscription Amounts are over-subscribed, then each
                  Stockholder subscribing for a portion of the Undersubscription
                  Amount shall only be entitled to purchase his pro rata portion
                  of the Undersubscription Amount (determined by dividing the
                  Basic Amount of each Stockholder subscribing for a portion of
                  the Undersubscription Amount by the sum of the Basic Amounts
                  of all Stockholders subscribing for a portion of the
                  Undersubscription Amount), subject to rounding by the Board of
                  Directors to the extent it deems reasonably necessary.

                  (c) The Company shall have 90 days from the expiration of the
                  period set forth in Section 3.1(b) above to issue, sell or
                  exchange all or any part of such Offered Securities as to
                  which a Notice of Acceptance has not been given by the
                  Stockholders (the "Refused Securities"), but only to the
                  offerees or purchasers described in the Offer (if so described
                  therein) and only upon terms and conditions (including,
                  without limitation, unit prices and interest rates) which are
                  not more favorable, to the acquiring person or persons or less
                  favorable to the Company than those set forth in the Offer.

                  (d) Any Offered Securities not acquired by the Stockholders or
                  other persons in accordance with Section 3.1(c) above may not
                  be issued, sold or exchanged until they are again offered to
                  the Stockholders under the procedures specified in this
                  Agreement.

                  (e) The rights of a Stockholder under this Section 3 shall not
                  apply to:

                           (i) Common Stock issued as a stock dividend to
                           holders of Common Stock or upon any subdivision or
                           combination of shares of Common Stock;

                           (ii) Preferred Stock issued as a stock dividend to
                           holders of Preferred Stock or upon any subdivision or
                           combination of shares of Preferred Stock;

                           (iii) the issuance of any shares of Common Stock upon
                           conversion of shares of Preferred Stock;

                           (iv) the issuance of up to 35,387,796 shares of
                           Common Stock or the grant of options therefor,
                           including shares issued upon exercise of options
                           outstanding on the date of this Agreement to
                           officers, directors, consultants, advisors and
                           employees of the Company or any subsidiary pursuant
                           to any plan, agreement or arrangement approved by a
                           vote of not


                                       19
<PAGE>
                           less than a majority of the Board of Directors of the
                           Company (such number of shares to be adjusted in the
                           event of stock splits, stock dividends,
                           reclassifications, recapitalizations or similar
                           events);

                           (v) securities issued solely in consideration for the
                           acquisition (whether by merger or otherwise) by the
                           Company or any of its subsidiaries of all or
                           substantially all of the stock or assets of any other
                           entity;

                           (vi) the issuance of up to 10,000,000 shares of
                           Common Stock (such number of shares to be adjusted in
                           the event of stock splits, stock dividends,
                           reclassifications, recapitalizations or similar
                           events) to creditors of the Company in satisfaction
                           of amounts payable by the Company in transactions
                           approved by the Board of Directors of the Company;

                           (vii) shares of Common Stock sold by the Company in
                           an underwritten public offering pursuant to an
                           effective registration statement under the Securities
                           Act;

                           (viii) shares of the Company's capital stock sold at
                           a "Subsequent Closing" (as that term is defined in
                           Section 2(b) of the Series A Preferred Stock Purchase
                           Agreement);

                           (ix) the sale by the Company of up to 266,667 shares
                           of the Company's Common Stock before May 31, 2000;

                           (x) the sale by the Company of up to 2,333,334 shares
                           of the Company's Series B Stock, before June 30,
                           2000;

                           (xi) the issuance of shares of the Company's Common
                           Stock to Enron pursuant to the terms of the Enron
                           Warrant;

                           (xii) the issuance of up to 763,305 shares of Common
                           Stock (such number of shares to be adjusted in the
                           event of stock splits, stock dividends,
                           reclassifications, recapitalizations or similar
                           events) to Enron pursuant to the terms of that Common
                           Stock Purchase Agreement dated as of September 20,
                           2000;

                           (xiii) the issuance of up to 60,000 shares of the
                           Company's Common Stock (such number of shares to be
                           adjusted in the event of stock splits, stock
                           dividends, reclassifications, recapitalizations or
                           similar events) to Andersen Consulting LLP (now know
                           as Accenture LLP) pursuant to the terms of that
                           certain Warrant Agreement dated as of December, 2000;
                           and

                           (xiv) the sale by the Company of Units (each Unit
                           consisting of a Note, Common Stock Warrants, and
                           Series C Warrants), including (a) the issuance of
                           shares of Series C Preferred Stock upon the exercise
                           of the Series C Warrants, (b) the issuance of shares
                           of Common Stock upon the


                                       20
<PAGE>

                           exercise of the Common Stock Warrants, and (c) Series
                           C Warrants issued as payment of interest on the
                           Notes, pursuant to the Note and Warrant Purchase
                           Agreement.

                  3.2. Termination. This Section 3 shall terminate upon the
         earliest of the following events:

                  (a) the sale of all or substantially all of the assets or
                  business of the Company, by merger, sale of assets or
                  otherwise; or

                  (b) the closing of the Initial Public Offering.

                  3.3. Termination of Series A Stockholders' Rights. The rights
         and obligations of the Series A Stockholders under this Section 3 shall
         terminate at such time as less than 25% of the aggregate of all
         originally issued shares of Series A Stock are outstanding (such number
         to be proportionately adjusted in the event of any stock splits, stock
         dividends, recapitalizations or similar events occurring on or after
         February 1, 2000).

                  3.4. Termination of Series B Stockholders' Rights. The rights
         and obligations of the Series B Stockholders under this Section 3 shall
         terminate at such time as less than 25% of the aggregate of all
         originally issued shares of Series B Stock are outstanding (such number
         to be proportionately adjusted in the event of any stock splits, stock
         dividends, recapitalizations or similar events occurring on or after
         February 1, 2000).

                  3.5. Termination of Series C Stockholders' Rights. The rights
         and obligations of the Series C Stockholders under this Section 3 shall
         terminate at such time as less than 25% of the aggregate of all
         originally issued shares of Series C Stock are outstanding (such number
         to be proportionately adjusted in the event of any stock splits, stock
         dividends, recapitalizations or similar events occurring on or after
         the date hereof).

                  3.6. Termination of Enron's Rights. Enron shall not be
         entitled to the rights of each Stockholder pursuant this Section 3 if
         that certain Price Posting Agreement dated as of December 4, 2000 (the
         "Posting Agreement") shall have been terminated (i) by Enron prior to
         the Interface Completion Date (as defined in the Posting Agreement)
         pursuant to Section 12(a)(i) through (xi) (except (iii)) of the Posting
         Agreement, (ii) by the Company at any time pursuant to Section 12(b) of
         the Posting Agreement or (iii) at any time pursuant to Section
         12(a)(iii) of the Posting Agreement.

         4. Transfers of Rights. This Agreement, and the rights and obligations
of each Stockholder hereunder, may be assigned by such Stockholder to (i) any
person or entity to which at least 50,000 Registrable Shares are transferred by
such Stockholder or (ii) to any partner, stockholder or Affiliate (as defined
below) of such Stockholder, and such transferee shall be deemed a "Stockholder"
for purposes of this Agreement; provided that the transferee provides written
notice of such assignment to the Company and agrees in writing to be bound
hereby. For purposes of the preceding sentence, an "Affiliate" of a Stockholder
is a person controlled by, controlling or under common control of such
Stockholder.

                                       21
<PAGE>
         5. General.

                  5.1. Severability. The invalidity or unenforceability of any
         provision of this Agreement shall not affect the validity or
         enforceability of any other provision of this Agreement.

                  5.2. Specific Performance. In addition to any and all other
         remedies that may be available at law in the event of any breach of
         this Agreement, each Stockholder shall be entitled to specific
         performance of the agreements and obligations of the Company hereunder
         and to such other injunctive or other equitable relief as may be
         granted by a court of competent jurisdiction.

                  5.3. Governing Law. This Agreement shall be governed by and
         construed in accordance with the internal laws of the State of Delaware
         (without reference to the conflicts of law provisions thereof).

                  5.4. Notices. All notices, requests, consents, and other
         communications under this Agreement shall be in writing and shall be
         deemed delivered (i) three business days after being sent by certified
         mail, return receipt requested, postage prepaid or (ii) one business
         day after being sent via a reputable nationwide overnight courier
         service guaranteeing next business day delivery, in each case to the
         intended recipient at his, her or its address as set forth in the
         Series A Preferred Stock Purchase Agreement, the Series B Preferred
         Stock Purchase Agreement, the Note and Warrant Purchase Agreement or,
         in the case of Enron,

                           Enron Net Works LLC
                           1400 South Street
                           Houston, Texas 77002
                           Attention: Compliance Department
                           Donna Lowry
                           Telephone: (713) 853-1939
                           Facsimile: (713) 646-4039

                  Any party may give any notice, request, consent or other
         communication under this Agreement using any other means (including,
         without limitation, personal delivery, messenger service, telecopy,
         first class mail or electronic mail), but no such notice, request,
         consent or other communication shall be deemed to have been duly given
         unless and until it is actually received by the party for whom it is
         intended. Any party may change the address to which notices, requests,
         consents or other communications hereunder are to be delivered by
         giving the other parties notice in the manner set forth in this
         Section.

                  5.5. Complete Agreement. This Agreement constitutes the entire
         agreement and understanding of the parties hereto with respect to the
         subject matter hereof and supersedes all prior agreements and
         understandings relating to such subject matter.

                  5.6. Amendments and Waivers. No amendment, modification or
         termination of, or waiver (other than a waiver as to only the rights of
         the particular party granting the waiver) under, any provision of this
         Agreement shall be valid unless in writing and signed by the holders of
         (i) 85% of the voting power of the Senior Registrable Shares, (ii)

                                       22
<PAGE>
         75% of the voting power of the Series A Stock, (iii) 75% of the voting
         power of the Series B Stock, and (iv) 85% of the voting power of the
         Series C Stock and the Series C Warrants (to the extent that the Series
         C Warrants are then exercisable), each as then outstanding (assuming
         the exercise and conversion into Common Stock of all securities
         exercisable therefor or convertible thereinto); provided that:

                  (a) the consent of the Company shall be required to effect any
                  amendment, modification or termination of, or waiver under,
                  any provision of this Agreement that adversely affects the
                  Company's rights or obligations set forth in this Agreement
                  (it being agreed that adding Stockholders pursuant to Section
                  5.6(c) does not adversely affect the Company's rights or
                  obligations set forth in this Agreement);

                  (b) any amendment, modification or waiver (other than a waiver
                  as to only the rights of the particular party granting the
                  waiver) under this Agreement that is not executed by all
                  Stockholders shall affect all Stockholders in the same
                  fashion;

                  (c) subsequent purchasers of the Company's capital stock, or
                  options to purchase such capital stock or securities
                  convertible into such capital stock, shall constitute
                  "Stockholders" for purposes of this Agreement and the
                  securities of the Company owned by such purchasers shall
                  constitute "Senior Registrable Shares" for purposes of this
                  Agreement;

                  (d) to the extent a provision of Section 2 of this Agreement
                  relates to Junior Registrable Shares, any amendment,
                  modification or waiver (other than a waiver as to only the
                  rights of the particular party granting the waiver) of such
                  provision shall require the written consent of holders of at
                  least 75% of the then-outstanding Junior Registrable Shares;
                  and

                  (e) any amendment, modification or termination effected in
                  accordance with this Section 5.6 shall be binding upon all
                  parties hereto.

         Notwithstanding the provisions of Section 5.6(iv) above, unless and
until the Subsequent Closing (as defined in the Note and Warrant Purchase
Agreement) occurs, no amendment, modification or termination of, or waiver
(other than a waiver as to only the rights of the particular party granting the
waiver) under any provision of this Agreement shall be valid unless in writing
and signed by the holders of 90% of the voting power of the Series C Stock and
the Series C Warrants (to the extent that the Series C Warrants are then
exercisable).

                  5.7. Pronouns. Whenever the context may require, any pronouns
         used in this Agreement shall include the corresponding masculine,
         feminine or neuter forms, and the singular form of nouns and pronouns
         shall include the plural, and vice versa.

                  5.8. Counterparts; Facsimile Signatures. This Agreement may be
         executed in any number of counterparts, each of which shall be deemed
         to be an original, and all of which together shall constitute one and
         the same document. This Agreement may be executed by facsimile
         signatures.

                                       23
<PAGE>
                  5.9. Section Headings. The section headings are for the
         convenience of the parties and in no way alter, modify, amend, limit or
         restrict the contractual obligations of the parties.

                  6.0 Subsequent Unit Purchasers. Any future purchaser of Units
         in accordance with the terms of the Note and Warrant Purchase Agreement
         may become a party to this Agreement after the date 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
         Unit Purchaser hereunder. SCHEDULE A hereto shall be amended from time
         to time to reflect the addition of any Unit Purchasers pursuant to this
         Section 6.0.



            [THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK]


                                       24
<PAGE>
         IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement
has been executed by the parties hereto as of the day and year first above
written.

                                       HOUSTONSTREET EXCHANGE, INC.

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

                                       BAYCORP HOLDINGS, LTD.

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

                                       EQUIVA TRADING COMPANY

                                       By: /s/ William Finnerty
                                           -------------------------------------
                                           Name: William Finnerty
                                           Title: Senior Vice President

                                       THOMAS H. LEE INVESTORS
                                       LIMITED PARTNERSHIP

                                       By: /s/ Wendy Masler
                                           -------------------------------------
                                           Name: Wendy Masler
                                           Title: Senior Vice President and
                                                  Treasurer

                                       TSG EQUITY FUND, L.P.

                                       By: /s/ T. Nathanael Shepherd
                                           -------------------------------------
                                           Name: T. Nathanael Shepherd
                                           Title: President

                                       TSG EQUITY PARTNERS LLC

                                       By: /s/ T. Nathanael Shepherd
                                           -------------------------------------
                                           Name: T. Nathanael Shepherd
                                           Title: President


                                       THOMAS R. SHEPHERD

                                       /s/ Thomas R. Shepherd
                                       -----------------------------------------


                                       25
<PAGE>
                                        T. NATHANAEL SHEPHERD

                                        /s/ T. Nathanael Shepherd
                                        ----------------------------------------


                                        FRANK W. GETMAN JR.

                                        /s/ Frank W. Getman Jr.
                                        ----------------------------------------


                                        ENRON NET WORKS LLC

                                        By: /s/ Andrew Zipper
                                            ------------------------------------
                                            Name: Andrew Zipper
                                            Title: Vice President


                                        MICHAEL DESROCHERS


                                        /s/ Michael Desrochers
                                        ----------------------------------------


                                        BARRETT MCDEVITT


                                        /s/ Barrett McDevitt
                                        ----------------------------------------


                                        PETER GETMAN


                                        /s/ Peter Getman
                                        ----------------------------------------


                                        JAMES S. GORDON


                                        /s/ James S. Gordon
                                        ----------------------------------------


                                        MITCHELL JACOBS


                                        /s/ Mitchell Jacobs
                                        ----------------------------------------


                                       26
<PAGE>
                                       WILLIAMS ENERGY MARKETING &
                                       TRADING COMPANY

                                       By: /s/ William C. Lawson
                                           -------------------------------------
                                           Name: William C. Lawson
                                           Title: Director

                                       SAPIENT CORPORATION

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

                                       BOWSTREET.COM, INC.

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

                                       OMEGA ADVISORS, INC. for and on behalf
                                       of Omega Capital Partners, L.P.,
                                       Omega International Partners, L.P.,
                                       Omega Overseas Partners, Ltd., and
                                       various institutional  accounts under
                                       the investment  management of Omega
                                       Advisors, Inc.

                                       By: /s/ David Bloom
                                           -------------------------------------
                                           Name: David Bloom
                                           Title: Chief Operating Officer

                                       ELLIOTT ASSOCIATES, L.P.

                                       By: /s/ Paul Singer
                                           -------------------------------------
                                           Name:
                                           Title:

                                       KROAD VENTURES, L.P.

                                       By: KRoad Partners, LLC
                                           Its General Partner

                                       By: /s/ David L. Tohir
                                           -------------------------------------
                                           Name: David L. Tohir
                                           Title: Senior Vice President


                                       27
<PAGE>
                                       VIVENDI, S.A.

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

                                       CONOCO, INC.

                                       By: /s/ E.L. Oshlo
                                           -------------------------------------
                                           Name: E.L. Oshlo
                                           Title: Vice President

                                       MICROARTS CORPORATION AFFILIATES

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



                                       28
<PAGE>
                                                                      SCHEDULE A



<TABLE>
<S>                                                     <C>
Thomas H. Lee Investors Limited Partnership                  200,000
       Attention: Soren Oberg
       75 State Street
       Boston, Massachusetts 02109

TSG Equity Fund, L.P.                                         55,217
       Attention: Thomas R. Shepherd
       636 Great Road
       Stow, MA 01775

TSG Equity Partners LLC                                          667
       Attention: Thomas R. Shepherd
       636 Great Road
       Stow, MA 01775

Thomas R. Shepherd                                             7,939
       c/o TSG Equity Partners LLC
       636 Great Road
       Stow, MA 01775

T. Nathanael Shepherd                                          2,844
       c/o TSG Equity Partners LLC
       636 Great Road
       Stow, MA 01775

Frank W. Getman Jr                                            60,000
       222 International Drive, Suite 125
       Portsmouth, New Hampshire 03801-6809

JUNIOR REGISTRABLE SHARES

BayCorp Holdings, Ltd.                                    10,000,000
       Attn. Frank W. Getman Jr
       222 International Drive, Suite 125
       Portsmouth, New Hampshire 03801-6809

Equiva Trading Company                                     4,814,815
       Attention:  William J. Finnerty
       One Allen Center
       500 Dallas Street
       Houston, Texas 77002
</TABLE>
<PAGE>
<TABLE>
<S>                                                     <C>
SENIOR REGISTRABLE SHARES

         COMMON STOCK


Enron Net Works LLC                                        1,781,043
       Attention: Compliance Department; Donna Lowry
       1400 Smith Street
       Houston, Texas 77002




Enron Net Works LLC                                          763,305
       Attention: Compliance Department; Donna Lowry    (Contingent Rights to
       1400 Smith Street                                Receive Common Stock)
       Houston, Texas 77002




Enron Net Works LLC                                        2,544,347
       Attention: Compliance Department; Donna Lowry    (Warrant to Purchase
       1400 Smith Street                                Common Stock)
       Houston, Texas 77002


         SERIES A CONVERTIBLE PREFERRED STOCK

Michael Desrochers                                            22,222
Barrett McDevitt                                              22,223
Peter Getman                                                  22,222
       c/o MicroArts Corporation
       655 Portsmouth Avenue
       Greenland, Portsmouth 03840

James S. Gordon                                               26,667
       86 Mt. Vernon Street
       Boston, Massachusetts 02108
</TABLE>

                                       2
<PAGE>
<TABLE>
<S>                                                     <C>
Williams Energy Marketing & Trading Company                  800,000
       Attention: Bill Hobbs
       One Williams Center
       P.O. Box 2848
       Tulsa, Oklahoma 74172

Sapient Corporation                                          266,667
       Attention: Wendy Kelly
       One Memorial Drive
       Cambridge, Massachusetts 02142

Bowstreet.com, Inc.                                           66,667
       Attention: Jack Serfass
       1 Harbour Place
       Portsmouth, New Hampshire 03801

Equiva Trading Company                                     1,066,667
       Attention:  William J. Finnerty
       One Allen Center
       500 Dallas Street
       Houston, Texas 77002

Omega Advisors, Inc.                                         666,667
       Attention:  David Bloom
       Wall Street Plaza
       88 Pine Street, 31st Floor
       New York, New York 10005

Elliott Associates, L.P.                                     666,667
       Attention: Michael R. Latina
       712 Fifth Avenue, 36th Floor
       New York, New York 10019

Equiva Trading Company                                       133,334
       Attention:  Arthur Nicoletti
       One Allen Center - 500 Dallas
       Houston, Texas 77002



</TABLE>

                                       3
<PAGE>
<TABLE>
<S>                                                     <C>
SERIES B CONVERTIBLE PREFERRED STOCK

KRoad Ventures, L.P.                                         416,667
       330 Madison Ave.
       25th Floor
       New York, NY 10017

Vivendi, S.A.                                                166,667
       c/o KRoad Ventures, L.P.
       330 Madison Ave.
       25th Floor
       New York, NY 10017

Conoco, Inc                                                  500,000
       600 N. Dairy Ashford
       MA 3128
       Houston, TX 77079-1175
</TABLE>

PURCHASERS OF UNITS

<TABLE>
<CAPTION>
            Name and Address                Units/Principal     No. of Series C   No. of Common Stock
            ----------------                ---------------     ---------------   -------------------
                                            Amount of Notes      Stock Warrants        Warrants
                                            ---------------      --------------        --------
<S>                                         <C>                 <C>               <C>
BayCorp Holdings, Ltd.                       $8,419,842.00         56,132,280          2,806,614
     Attn:  Frank W. Getman, Jr
     222 International Drive, Suite 125
     Portsmouth, NH 03801-6809
TSG Equity Fund, L.P.                        $   17,763.11            118,421              5,920
     Attn:  Thomas R. Shepherd
     636 Great Road
     Stow, MA 01775
TSG Equity Partners LLC                      $      179.43              1,196                 60
     Attn:  Thomas R. Shepherd
     636 Great Road
     Stow, MA 01775
Thomas R. Shepherd                           $   21,503.60             10,024                501
     c/o TSG Equity Partners LLC
     636 Great Road
     Stow, MA 01775
T. Nathanael Shepherd                        $      553.86              3,692                185
     c/o TSG Equity Partners LLC
     636 Great Road
     Stow, MA 01775
James S. Gordon                              $  187,500.00          1,250,000             62,500
     86 Mt. Vernon Street
     Boston, MA 02108
Mitchell Jacobs                              $  125,000.00            833,334             41,667
     1 Energy Road
     North Dartmouth, MA 02747
KRoad Ventures                               $  160,000.00          1,066,667             53,334
     330 Madison Avenue
     25th Floor
     New York, NY 10017
</TABLE>

                                       4
<PAGE>
<TABLE>
<S>                                         <C>                 <C>               <C>
Equiva Trading Company                       $1,394,354.00          9,295,693            464,785
     Attention:  William J. Finnerty
     One Allen Center
     500 Dallas Street
     Houston, TX 77002
Omega Advisors, Inc.                         $  180,000.00          1,200,000             60,000
     Attention: Ed Levy
     Wall Street Plaza
     88 Pine Street, 31st Floor
     New York, NY 10005
Michael A. Desrochers                        $   83,333.00            555,553             27,778
     c/o MicroArts Corporation
     655 Portsmouth Avenue
     Portsmouth, NH 03840
Barrett McDevitt                             $   83,334.00            555,560             27,778
     c/o MicroArts Corporation
     655 Portsmouth Avenue
     Portsmouth, NH 03840
Peter L. Getman                              $   83,333.00            555,553             27,778
     c/o MicroArts Corporation
     655 Portsmouth Avenue
     Portsmouth, NH 03840
Conoco, Inc.                                 $  437,819.00          2,918,793            145,940
     600 N. Dairy Ashford
     MA 3128
     Houston, TX 77079-1175
Thomas H. Lee Investors Limited              $      75,000            500,000             25,000
Partnership
     75 State Street
     Boston, MA 02109
Vivendi, S.A
     330 Madison Avenue
     25th Floor
     New York, NY 10017
</TABLE>


                                       5