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                             AMENDMENT NO. 2 TO THE
                  AMENDED AND RESTATED JOINT SERVICES AGREEMENT

     This Amendment No. 2 to the Amended and Restated Joint Services Agreement
between Cantor Fitzgerald, L.P., on behalf of itself and its direct and
indirect, current and future, subsidiaries, other than eSpeed, Inc. and its
direct and indirect, current and future, subsidiaries, and eSpeed, Inc., on
behalf of itself and its direct and indirect, current and future subsidiaries,
dated as of April 1, 2001 (the "JSA"), as amended by Amendment No.1, dated
January 30, 2002, is made as of this 11th day of October 2002. Capitalized terms
used herein and not defined herein shall have the meanings ascribed in the JSA.

                              W I T N E S S E T H:

     WHEREAS, pursuant to the JSA, the eSpeed Parties and the Cantor Parties
agreed, among other things, to collaborate in providing brokerage services to
customers through the then existing Electronic Marketplaces, and in creating and
developing Electronic Marketplaces for new Financial Products and other
Products;

     WHEREAS, CFLP has formed CO2e.com, LLC, a Delaware limited liability
company ("CO2e"), which engages in the business of sponsoring a real-time
Electronic Emissions Marketplace (as defined below) and affiliated web portal,
which may be accessed directly through fully electronic means or through brokers
via telephone, in and through which buyers and sellers of GHG Emission Reduction
Units (as defined below) may effect transactions in those GHG Emission Reduction
Units;

     WHEREAS, in connection with the formation of CO2e, concurrently with the
execution of this Amendment, eSpeed will enter into a Services Agreement with
CO2e pursuant to which eSpeed will generally provide, among other things, the
global technology infrastructure for the transaction elements of the Electronic
Emissions Marketplace;

     WHEREAS, concurrently with the execution of this Amendment, CFLP will enter
into an Administrative Services Agreement with CO2e pursuant to which CFLP will
generally provide CO2e with certain services, including, without limitation,
office space, personnel and corporate services, such as cash management,
internal audit, facilities management, promotional sales and marketing, legal,
payroll, benefits administration and other administrative services;

     WHEREAS, in accordance with the terms and conditions of the JSA, eSpeed's
and CFLP's provision of services to CO2e is subject to the terms and conditions
of the JSA; and

     WHEREAS, the parties to the JSA desire to amend the JSA to allow for such
provision of services.

     NOW THEREFORE, in consideration of the premises, mutual covenants and
agreements contained herein and for other good and valuable consideration, the
receipt and adequacy of which is hereby acknowledged, the Cantor Parties and the
eSpeed Parties hereby agree as follows:


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     1.   Section 1 of the JSA hereby is amended to incorporate the following
Defined Terms in their appropriate alphabetical order:

          "CO2e" means CO2e.com, LLC and its subsidiaries.

          "Convention" means the United Nations Framework Convention on Climate
          Change.

          "Electronic Emissions Marketplace" means the marketplace and
          affiliated web portal sponsored by CO2e on or through which wholesale
          transactions in, and purchases and sales of, GHG Emission Reduction
          Units and derivatives thereof, including futures contracts and options
          on futures contracts involving GHG Emission Reduction Units (and
          related services) may be effected in whole or in part electronically.

          "Emissions Government Agency" means any national, international,
          federal, provincial, state, municipal, county, regional or local
          government or authority, and includes: (i) any department, commission,
          bureau, board, administrative agency or regulatory body of any
          government; (ii) an Emissions International Agency; (iii) any person
          or corporation acting as a Registrar in connection with a GHG Emission
          Reductions Registry; or (iv) any person or corporation acting as an
          agent for an Emissions Governmental Agency.

          "Emissions International Agency" means any international commission,
          bureau, board, administrative agency or regulatory body responsible
          for measures to achieve objectives of the Convention.

          "GHG Emissions" means carbon dioxide, methane, nitrous oxide,
          hydrofluorocarbons, perflurocarbons and any other gas substance that
          is the subject of the Convention and related protocols, treaties,
          agreements and instruments, or other gases, tradable renewable energy
          instruments, and other tradable environmental instruments subject to
          domestic, regional, or international regulation.

          "GHG Emission Reductions" means a reduction in GHG Emissions.

          "GHG Emission Reduction Units" means all rights, benefits, title and
          interest related, in whole or in part, to GHG Emission Reductions, or
          derivatives thereof, including futures contracts and options on
          futures contracts involving GHG Emission Reduction Units, whether in
          existence as of the date of this Agreement or arising in the future,
          without limitation: (i) any credit issued or granted by an Emissions
          Government Agency in connection with GHG Emission Reductions; (ii) any
          tradable allowance or allocated pollution right issued or granted in
          connection with GHG Emission Reductions; (iii) the sole right to claim
          credit in any reporting program established or maintained by any
          Emissions Government Agency for creation of GHG Emission Reductions;
          (iv) the sole right to bank GHG Emission Reductions in any registry
          system established or maintained by any Emissions Government Agency or
          non-governmental organization or entity (a "GHG Emission Reductions
          Registry"); (v) the sole right to any form of acknowledgment by an
          Emissions Governmental Agency that actions have been taken by a party
          or parties in connection with GHG Emission Reductions that result in
          the reduction, avoidance, sequestration or mitigation of GHG
          Emissions; (vi) the sole right to use GHG Emission


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          Reductions; (vii) the sole right to any form of acknowledgment by an
          Emissions Government Agency to claim reduction from an emissions
          baseline when that baseline can be used for establishing a tradable
          GHG Emission allowance allocation, and that beneficial ownership in
          this reduction, avoidance, sequestration or mitigation or related
          tradable allowances can be; (viii) banked for credit in the event of
          regulation requiring a party to reduce, avoid, compensate for or
          otherwise mitigate GHG Emissions; (ix) claimed by a party for credit
          against that party's compliance requirement; (x) put to any other
          sanctioned use; or (xi) transferred to another party for any reason;
          (xii) the sole right to any form of acknowledgment by an Emissions
          International Agency in respect of GHG Emission Reductions including
          that the GHG Emission Reductions constitute tradable emissions
          reduction units; and (xiii) the sole right to any offset of
          anthropogenic GHG Emissions caused wholly or in part by the GHG
          Emission Reductions.

          "TradeSpark" means TradeSpark, L.P.

     2.   The following Defined Terms in Section 1 of the JSA hereby are amended
and replaced in their entirety with the following:

          "Ancillary IT Services" means technology support services (other than
          in respect of the Electronic Energy Marketplace and the Electronic
          Emissions Marketplace), including, but not limited to, (i) systems
          administration, (ii) internal network support, (iii) support and
          procurement for desktops of Cantor Party end-user equipment, (iv)
          operations and disaster recovery services, (v) voice communications,
          (vi) support and development of systems for Clearance, Settlement and
          Fulfillment Services, (vii) systems support for Cantor Party brokers,
          and (viii) electronic applications systems and network support and
          development for Unrelated Dealer Businesses; provided that Ancillary
          IT Services does not include the provision of desktop hardware for use
          by Cantor Party employees.

          "Collaborative Marketplace" means an Electronic Marketplace that is
          operated by a Cantor Party and an eSpeed Party in collaboration
          pursuant to Section 3 of this Agreement. All Marketplaces shall be
          Collaborative Marketplaces, unless otherwise determined in accordance
          with this Agreement. In no event shall the Electronic Energy
          Marketplace, the Electronic Emissions Marketplace or a marketplace
          involved in a Gaming Business or an Unrelated Dealer Business be
          deemed to be a Collaborative Marketplace for purposes of this
          Agreement.

          "Electronic Marketplace" means a Marketplace on which transactions in,
          and purchases and sales of, Products may be effected in whole or in
          part electronically, but does not include a Marketplace that is merely
          electronically assisted, such as screen assisted open outcry. In no
          event shall the Electronic Energy Marketplace, the Electronic
          Emissions Marketplace or a marketplace involved in a Gaming Business
          or an Unrelated Dealer Business be deemed to be an Electronic
          Marketplace for purposes of this Agreement.

          "Financial Product" means any financial asset or financial instrument,
          any intangible commodity or any tangible fungible commodity,
          including, but not limited to, any security, futures contract, foreign
          exchange transaction, swap transaction, credit derivative, repurchase
          or reverse repurchase obligation, currency or swap (as currently


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          defined in the Federal Bankruptcy Code of 1978) or any option or
          derivative on any of the foregoing; provided that in no event shall
          (x) any Energy Product traded on the Electronic Energy Marketplace or
          any derivative thereof, including futures contracts and options on
          futures contracts involving Energy Products traded on the Electronic
          Energy Marketplace or (y) any GHG Emission Reduction Unit traded on
          the Electronic Emissions Marketplace or any derivative thereof,
          including futures contracts and options on futures contracts involving
          GHG Emission Reduction Units traded on the Electronic Emissions
          Marketplace, be considered a Financial Product, or (z) any product
          traded in a marketplace involving a Gaming Business or an Unrelated
          Dealer Business be considered a Financial Product.

          "Marketplace" means a marketplace operated or to be operated by the
          Cantor Parties and/or the eSpeed Parties in and through which buyers
          and sellers of a Product may effect transactions in the Product. In no
          event shall the Electronic Energy Marketplace, the Electronic
          Emissions Marketplace or a marketplace involved in a Gaming Business
          or an Unrelated Dealer Business be deemed to be a Marketplace for
          purposes of this Agreement.

          "Product" means any tangible or intangible asset or good, other than
          (x) an Energy Product traded on the Electronic Energy Marketplace or
          any derivative thereof, including futures contracts and options on
          futures contracts involving Energy Products traded on the Electronic
          Energy Marketplace, (y) a GHG Emission Reduction Unit traded on the
          Electronic Emissions Marketplace or any derivative thereof, including
          futures contracts and options on futures contracts involving GHG
          Emission Reduction Units traded on the Electronic Emissions
          Marketplace or (z) a product traded in a marketplace involving a
          Gaming Business or an Unrelated Dealer Business.

     3.   Section 7(f) of the JSA hereby is amended and replaced in its entirety
with the following:

          No eSpeed Party shall, directly, indirectly or in connection with a
          third Person, engage in any activities competitive with a business
          activity now or hereafter conducted by a Cantor Party or provide or
          assist any other Person in providing any Cantor Service, other than
          (i) in collaboration with a Cantor Party pursuant to Section 3 of this
          Agreement, (ii) with respect to a new Marketplace involving a
          Financial Product, after CFLP (x) has indicated that it is unable or
          unwilling to provide such Cantor Service or (y) fails to indicate to
          the eSpeed Party within the prescribed 30-day period that it does wish
          to provide such Cantor Service with respect to that Marketplace in
          accordance with paragraph (d) of this Section 7, (iii) with respect to
          a new Marketplace involving a Product that is not a Financial Product,
          an Energy Product traded on the Electronic Energy Marketplace or a GHG
          Emission Reduction Unit traded on the Electronic Emissions Marketplace
          in accordance with paragraph (c) or paragraph (e) of this Section 7,
          (iv) with respect to an Unrelated Dealer Business in which an eSpeed
          Party develops and operates a fully electronic Marketplace, (v) with
          respect to the Electronic Energy Marketplace, or (vi) with respect to
          the Electronic Emissions Marketplace. No eSpeed Party shall, directly,
          indirectly or in connection with a third Person, engage in or
          otherwise provide services for any Gaming Business, or engage in or
          otherwise provide


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          services for any activities that are not within the definition of
          Gaming Business but would be if so designated by a Cantor Party, as
          set forth in the definition of Gaming Business herein, without the
          prior written consent of CFLP.

     4.   Section 7(g) of the JSA hereby is amended and replaced in its entirety
with the following:

          No Cantor Party shall, directly, indirectly or in connection with a
          third Person, provide or assist any other Person in providing
          Electronic Brokerage Services, other than (i) in collaboration with
          eSpeed pursuant to Section 3 of this Agreement, (ii) with respect to a
          new Marketplace, after eSpeed (x) has indicated that it is unable to
          develop and put into operation an Electronic Trading System with
          respect to that new Marketplace in accordance with paragraph (a) of
          this Section 7 or (y) has declined to exercise its right of first
          refusal or is unable to develop and put into operation an Electronic
          Trading System with respect to that new Marketplace in accordance with
          paragraph (b) of this Section 7, including, without limitation, the
          time period specified therein, (iii) with respect to an Unrelated
          Dealer Business, (iv) with respect to the Electronic Energy
          Marketplace, (v) with respect to the Electronic Emissions Marketplace
          or (vi) with respect to a Gaming Business.

     5.   Section 7(i) of the JSA hereby is amended and replaced in its entirety
with the following:

          The Cantor Parties and the eSpeed Parties shall be entitled to and may
          enter into strategic alliances, joint ventures, partnerships or
          similar arrangements with Persons and consummate Business Combinations
          with Persons (all of the foregoing, collectively, "Alliance
          Opportunities") on the following basis only. If an Alliance
          Opportunity (i) relates to a Person that directly or indirectly
          provides Cantor Services and engages in business operations that do
          not involve Electronic Brokerage Services, then any Cantor Party shall
          be entitled to consummate a transaction with respect to such an
          Alliance Opportunity, (ii) relates to a Person that directly or
          indirectly provides Electronic Brokerage Services and engages in
          business operations that do not involve any Cantor Service, then any
          eSpeed Party shall be entitled to consummate a transaction with
          respect to such an Alliance Opportunity and (iii) is an Alliance
          Opportunity with respect to a Person other than those described in
          clauses (i) and (ii) above, then the Cantor Parties and the eSpeed
          Parties shall cooperate to jointly pursue and consummate a transaction
          with respect to such Alliance Opportunity on mutually agreeable terms,
          provided, however that any Alliance Opportunity with TradeSpark with
          respect to the Electronic Energy Marketplace shall not be considered
          an Alliance Opportunity and any such Alliance Opportunity with
          TradeSpark with respect to the Electronic Energy Marketplace shall be
          specifically permitted in accordance with the terms and conditions
          agreed to by any eSpeed Party or any Cantor Party, and any Alliance
          Opportunity with CO2e with respect to the Electronic Emissions
          Marketplace shall not be considered an Alliance Opportunity and any
          such Alliance Opportunity with CO2e with respect to the Electronic
          Emissions Marketplace shall be specifically permitted in accordance
          with the terms and conditions agreed to by any eSpeed Party or any
          Cantor Party. For purposes of this paragraph, a "Business Combination"
          shall mean, with respect to any Person (other than TradeSpark


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          with respect to the Electronic Energy Marketplace and other than CO2e
          with respect to the Electronic Emissions Marketplace), a transaction
          initiated by and/or in which a Cantor Party or an eSpeed Party is the
          acquiror involving (i) a merger, consolidation, amalgamation or
          combination, (ii) any sale, dividend, split or other disposition of
          any capital stock or other equity interests (or securities convertible
          into or exchangeable for or options or warrants to purchase any
          capital stock or other equity equivalents) of the Person, (iii) any
          tender offer (including without limitation a self-tender), exchange
          offer, recapitalization, liquidation, dissolution or similar
          transaction, (iv) any sale, dividend or other disposition of a
          significant portion of the assets and properties of the Person (even
          if less than all or substantially all of such assets or properties),
          and (v) entering into of any agreement or understanding, or the
          granting of any rights or options, with respect to any of the
          foregoing.

     6.   Notwithstanding anything else contained herein or in the JSA to the
contrary, in no event shall eSpeed's or CFLP's direct or indirect relationship
with CO2e with respect to the Electronic Emissions Marketplace be deemed to be a
violation of the JSA.

     7.   Except as expressly set forth herein, the JSA shall remain in full
force and effect.

     IN WITNESS WHEREOF, the parties hereto have executed or caused this
Amendment No. 2 to be executed in their respective names by their respective
officers thereunto duly authorized, as of the date first written above.

                                       CANTOR FITZGERALD, L.P.,
                                       on behalf of itself and its direct and
                                       indirect, current and future,
                                       subsidiaries, other than eSpeed, Inc.
                                       and its current and future, subsidiaries

                                       By: CF Group Management, Inc.,
                                       its Managing General Partner

                                       By:  /s/ Howard W. Lutnick
                                       Name:  Howard W. Lutnick
                                       Title: President

                                       ESPEED, INC.,
                                       on behalf of itself and its direct and
                                       indirect, current and future,
                                       subsidiaries

                                       By:  /s/ Howard W. Lutnick
                                       Name:  Howard W. Lutnick
                                       Title: Chairman, Chief Executive
                                       Officer and President


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