ADDENDUM
      TO SUBSCRIPTION AGREEMENT

     

    Reference
      is made to each of those Subscription Agreements, dated as of May __, 2007,
      between MSTI Holdings, Inc., a Delaware corporation (the “Company”)
      and
      each of the subscribers (the “Subscribers”)
      for
      Units (as defined in the Company’s
      Confidential Private Placement Memorandum (the “PPM”)
      dated
      May 7, 2007, as supplemented to date)
      (the
“Subscription
      Agreements”).
      The
      Company hereby provides the following Addendum (this “Addendum”)
      to the
      Subscription Agreements for the benefit of each Subscriber. Capitalized terms
      used herein but not otherwise defined shall have the meanings ascribed to them
      in the Subscription Agreements or the PPM.

     

    1. Additional
      Representations and Warranties.
      The
      provisions appearing under the heading “II. Representations of the Company” in
      the Subscription Agreements is deleted and replaced in its entirety with the
      following:

     

    2.1 The
      Company represents and warrants to the Subscriber that as of the date of the
      closing of the Offering (the “Closing
      Date”):

     

    (a)  Subsidiaries.
      All of
      the direct and indirect subsidiaries of the Company are set forth on
Schedule
      2.1(a).
      The
      Company owns, directly or indirectly, all of the capital stock or other equity
      interests of each Subsidiary free and clear of any Liens, and all of the issued
      and outstanding shares of capital stock of each Subsidiary are validly issued
      and are fully paid, non-assessable and free of preemptive and similar rights
      to
      subscribe for or purchase securities. If the Company has no subsidiaries, all
      other references to the Subsidiaries or any of them in the Transaction Documents
      shall be disregarded.

     

    (b)  Organization
      and Qualification.
      The
      Company and each of the Subsidiaries is an entity duly incorporated or otherwise
      organized, validly existing and in good standing under the laws of the
      jurisdiction of its incorporation or organization (as applicable), with the
      requisite power and authority to own and use its properties and assets and
      to
      carry on its business as currently conducted. Neither the Company nor any
      Subsidiary is in violation or default of any of the provisions of its respective
      certificate or articles of incorporation, bylaws or other organizational or
      charter documents. Each of the Company and the Subsidiaries is duly qualified
      to
      conduct business and is in good standing as a foreign corporation or other
      entity in each jurisdiction in which the nature of the business conducted or
      property owned by it makes such qualification necessary, except where the
      failure to be so qualified or in good standing, as the case may be, could not
      have or reasonably be expected to result in (i) a material adverse effect on
      the
      legality, validity or enforceability of any Transaction Document, (ii) a
      material adverse effect on the results of operations, assets, business,
      prospects or condition (financial or otherwise) of the Company and the
      Subsidiaries, taken as a whole, or (iii) a material adverse effect on the
      Company’s ability to perform in any material respect on a timely basis its
      obligations under any Transaction Document (any of (i), (ii) or (iii), a
“Material
      Adverse Effect”)
      and no
      Proceeding has been instituted in any such jurisdiction revoking, limiting
      or
      curtailing or seeking to revoke, limit or curtail such power and authority
      or
      qualification.

     

    
      
        
        

      

      
        
        

        
          

        

      

      
        
        

      

    

     

    (c)  Authorization;
      Enforcement.
      The
      Company has the requisite corporate power and authority to enter into and to
      consummate the transactions contemplated by each of the Transaction Documents
      and otherwise to carry out its obligations hereunder and thereunder. The
      execution and delivery of each of the Transaction Documents by the Company
      and
      the consummation by it of the transactions contemplated hereby and thereby
      have
      been duly authorized by all necessary action on the part of the Company and
      no
      further action is required by the Company, the Board of Directors or the
      Company’s stockholders in connection therewith other than in connection with the
      Required Approvals. Each Transaction Document has been (or upon delivery will
      have been) duly executed by the Company and, when delivered in accordance with
      the terms hereof and thereof, will constitute the valid and binding obligation
      of the Company enforceable against the Company in accordance with its terms,
      except (i) as limited by general equitable principles and applicable bankruptcy,
      insolvency, reorganization, moratorium and other laws of general application
      affecting enforcement of creditors’ rights generally, (ii) as limited by laws
      relating to the availability of specific performance, injunctive relief or
      other
      equitable remedies and (iii) insofar as indemnification and contribution
      provisions may be limited by applicable law.

     

    (d)  No
      Conflicts.
      The
      execution, delivery and performance of the Transaction Documents by the Company
      and the consummation by the Company of the other transactions contemplated
      hereby and thereby do not and will not: (i) conflict with or violate any
      provision of the Company’s or any Subsidiary’s certificate or articles of
      incorporation, bylaws or other organizational or charter documents, or (ii)
      conflict with, or constitute a default (or an event that with notice or lapse
      of
      time or both would become a default) under, result in the creation of any Lien
      upon any of the properties or assets of the Company or any Subsidiary, or give
      to others any rights of termination, amendment, acceleration or cancellation
      (with or without notice, lapse of time or both) of, any agreement, credit
      facility, debt or other instrument (evidencing a Company or Subsidiary debt
      or
      otherwise) or other understanding to which the Company or any Subsidiary is
      a
      party or by which any property or asset of the Company or any Subsidiary is
      bound or affected, or (iii) subject to the Required Approvals, conflict with
      or
      result in a violation of any law, rule, regulation, order, judgment, injunction,
      decree or other restriction of any court or governmental authority to which
      the
      Company or a Subsidiary is subject (including federal and state securities
      laws
      and regulations), or by which any property or asset of the Company or a
      Subsidiary is bound or affected; except in the case of each of clauses (ii)
      and
      (iii), such as could not have or reasonably be expected to result in a Material
      Adverse Effect.

     

    (e)  Filings,
      Consents and Approvals.
      The
      Company is not required to obtain any consent, waiver, authorization or order
      of, give any notice to, or make any filing or registration with, any court
      or
      other federal, state, local or other governmental authority or other Person
      in
      connection with the execution, delivery and performance by the Company of the
      Transaction Documents, other than (i) the filings with the Commission of a
      Current Report on Form 8-K disclosing the material terms of the transactions
      contemplated by the PPM and attaching the Transaction Documents thereto, (ii)
      the filing with the Commission of the Registration Statement, (iii) the notice
      and/or application(s) to each applicable Trading Market for the issuance and
      sale of the Common Stock included in the Units for trading thereon in the time
      and manner required thereby and (iv) the filing of Form D with the Commission
      and such filings as are required to be made under applicable state securities
      laws (collectively, the “Required
      Approvals”).

     

    
      
        
        

      

      
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    (f)  Issuance
      of the Securities.
      The
      Securities are duly authorized and, when issued and paid for in accordance
      with
      the applicable Transaction Documents, will be duly and validly issued, fully
      paid and nonassessable, free and clear of all Liens imposed by the Company
      other
      than restrictions on transfer provided for in the Transaction Documents. The
      Common Stock included in the Units, when issued in accordance with the terms
      of
      the Transaction Documents, will be validly issued, fully paid and nonassessable,
      free and clear of all Liens imposed by the Company other than restrictions
      on
      transfer provided for in the Transaction Documents. The Company has reserved
      from its duly authorized capital stock a number of shares of Common Stock for
      issuance of the Common Stock included in the Units at least equal to the
      Required Minimum on the date hereof. 

     

    (g)  Capitalization.
      The
      capitalization of the Company is as set forth on Schedule
      2.1(g),
      which
Schedule
      2.1(g)
      shall
      also include the number of shares of Common Stock owned beneficially, and of
      record, by Affiliates of the Company as of the date hereof. The Company has
      not
      issued any capital stock since its most
      recently filed periodic report under the Exchange Act,
      other
      than pursuant to (i) the Merger, (ii) any transaction described in the PPM
      or
      (iii) the exercise of employee stock options under the Company’s stock option
      plans, the issuance of shares of Common Stock to employees pursuant to the
      Company’s employee stock purchase plan and pursuant to the conversion or
      exercise of Common Stock Equivalents outstanding as of the date of the most
      recently filed periodic report under the Exchange Act. No Person has any right
      of first refusal, preemptive right, right of participation, or any similar
      right
      to participate in the transactions contemplated by the Transaction Documents.
      Except as a result of the purchase and sale of the Securities, there are no
      outstanding options, warrants, scrip rights to subscribe to, calls or
      commitments of any character whatsoever relating to, or securities, rights
      or
      obligations convertible into or exercisable or exchangeable for, or giving
      any
      Person any right to subscribe for or acquire, any shares of Common Stock, or
      contracts, commitments, understandings or arrangements by which the Company
      or
      any Subsidiary is or may become bound to issue additional shares of Common
      Stock
      or Common Stock Equivalents. The issuance and sale of the Securities will not
      obligate the Company to issue shares of Common Stock or other securities to
      any
      Person (other than the Subscribers) and will not result in a right of any holder
      of Company securities to adjust the exercise, conversion, exchange or reset
      price under any of such securities. All of the outstanding shares of capital
      stock of the Company are validly issued, fully paid and nonassessable, have
      been
      issued in compliance with all federal and state securities laws, and none of
      such outstanding shares was issued in violation of any preemptive rights or
      similar rights to subscribe for or purchase securities. No further approval
      or
      authorization of any stockholder, the Board of Directors or others is required
      for the issuance and sale of the Securities. There are no stockholders
      agreements, voting agreements or other similar agreements with respect to the
      Company’s capital stock to which the Company is a party or, to the knowledge of
      the Company, between or among any of the Company’s stockholders.

     

    
      
        
        

      

      
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    (h)  SEC
      Reports; Financial Statements.
      The
      Company has filed all reports, schedules, forms, statements and other documents
      required to be filed by the Company under the Securities Act and the Exchange
      Act, including pursuant to Section 13(a) or 15(d) thereof, for the two years
      preceding the date hereof (or such shorter period as the Company was required
      by
      law or regulation to file such material) (the foregoing materials, including
      the
      exhibits thereto and documents incorporated by reference therein, being
      collectively referred to herein as the “SEC
      Reports”)
      on a
      timely basis or has received a valid extension of such time of filing and has
      filed any such SEC Reports prior to the expiration of any such extension. As
      of
      their respective dates, the SEC Reports complied in all material respects with
      the requirements of the Securities Act and the Exchange Act, as applicable,
      and
      none of the SEC Reports, when filed, contained any untrue statement of a
      material fact or omitted to state a material fact required to be stated therein
      or necessary in order to make the statements therein, in the light of the
      circumstances under which they were made, not misleading. The audited financial
      statements of the Microwave Satellite Technologies, Inc., a New Jersey
      corporation (the “MST
      Subsidiary”)
      and
      its direct and indirect subsidiaries for the past two fiscal years and unaudited
      financial statements for the most recent fiscal quarter are attached hereto
      as
Schedule
      2.1(h).
      Such
      financial statements comply in all material respects with applicable accounting
      requirements and the rules and regulations of the Commission with respect
      thereto as in effect at the time of filing. Such financial statements have
      been
      prepared in accordance with United States generally accepted accounting
      principles applied on a consistent basis during the periods involved
      (“GAAP”),
      except as may be otherwise specified in such financial statements or the notes
      thereto and except that unaudited financial statements may not contain all
      footnotes required by GAAP, and fairly present in all material respects the
      financial position of the MST Subsidiary and its consolidated Subsidiaries
      as of
      and for the dates thereof and the results of operations and cash flows for
      the
      periods then ended, subject, in the case of unaudited statements, to normal,
      immaterial, year-end audit adjustments. The financial statements of the Company
      included in the SEC Reports comply in all material respects with applicable
      accounting requirements and the rules and regulations of the Commission with
      respect thereto as in effect at the time of filing. Such financial statements
      comply in all material respects with applicable accounting requirements and
      the
      rules and regulations of the Commission with respect thereto as in effect at
      the
      time of filing. Such financial statements have been prepared in accordance
      with
      GAAP, except as may be otherwise specified in such financial statements or
      the
      notes thereto and except that unaudited financial statements may not contain
      all
      footnotes required by GAAP, and fairly present in all material respects the
      financial position of the Company and its consolidated Subsidiaries as of and
      for the dates thereof and the results of operations and cash flows for the
      periods then ended, subject, in the case of unaudited statements, to normal,
      immaterial, year-end audit adjustments.

     

    (i)  Material
      Changes.
      Since
      the date of the latest audited financial statements included attached hereto
      as
      Schedule 2.1(h), except as specifically disclosed on Schedule
      2.1(i),
      (i)
      there has been no event, occurrence or development that has had or that could
      reasonably be expected to result in a Material Adverse Effect, (ii) the Company
      has not incurred any liabilities (contingent or otherwise) other than (A) trade
      payables and accrued expenses incurred in the ordinary course of business
      consistent with past practice and (B) liabilities not required to be reflected
      in the Company’s financial statements pursuant to GAAP or disclosed in filings
      made with the Commission, (iii) the Company has not altered its method of
      accounting, (iv) the Company has not declared or made any dividend or
      distribution of cash or other property to its stockholders or purchased,
      redeemed or made any agreements to purchase or redeem any shares of its capital
      stock and (v) the Company has not issued any equity securities to any officer,
      director or Affiliate, except pursuant to existing Company stock option plans.
      The Company does not have pending before the Commission any request for
      confidential treatment of information. Except for the issuance of the Securities
      contemplated by the Subscription Agreement or as set forth on Schedule
      2.1(i),
      no
      event, liability or development has occurred or exists with respect to the
      Company or its Subsidiaries or their respective business, properties, operations
      or financial condition, that would be required to be disclosed by the Company
      under applicable securities laws at the time this representation is made or
      deemed made that has not been publicly disclosed at least one Trading Day prior
      to the date that this representation is made.

     

    
      
        
        

      

      
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    (j)  Litigation.
      There
      is no action, suit, inquiry, notice of violation, proceeding or investigation
      pending or, to the knowledge of the Company, threatened against or affecting
      the
      Company, any Subsidiary or any of their respective properties before or by
      any
      court, arbitrator, governmental or administrative agency or regulatory authority
      (federal, state, county, local or foreign) (collectively, an “Action”)
      which
      (i) adversely affects or challenges the legality, validity or enforceability
      of
      any of the Transaction Documents or the Securities or (ii) could, if there
      were
      an unfavorable decision, have or reasonably be expected to result in a Material
      Adverse Effect. Neither the Company nor any Subsidiary, nor any director or
      officer thereof, is or has been the subject of any Action involving a claim
      of
      violation of or liability under federal or state securities laws or a claim
      of
      breach of fiduciary duty. There has not been, and to the knowledge of the
      Company, there is not pending or contemplated, any investigation by the
      Commission involving the Company or any current or former director or officer
      of
      the Company. The Commission has not issued any stop order or other order
      suspending the effectiveness of any registration statement filed by the Company
      or any Subsidiary under the Exchange Act or the Securities Act. 

     

    (k)  Labor
      Relations.
      No
      material labor dispute exists or, to the knowledge of the Company, is imminent
      with respect to any of the employees of the Company which could reasonably
      be
      expected to result in a Material Adverse Effect. None of the Company’s or its
      Subsidiaries’ employees is a member of a union that relates to such employee’s
      relationship with the Company or such Subsidiary, and neither the Company nor
      any of its Subsidiaries is a party to a collective bargaining agreement, and
      the
      Company and its Subsidiaries believe that their relationships with their
      employees are good. No executive officer, to the knowledge of the Company,
      is,
      or is now expected to be, in violation of any material term of any employment
      contract, confidentiality, disclosure or proprietary information agreement
      or
      non-competition agreement, or any other contract or agreement or any restrictive
      covenant in favor of any third party, and the continued employment of each
      such
      executive officer does not subject the Company or any of its Subsidiaries to
      any
      liability with respect to any of the foregoing matters. The Company and its
      Subsidiaries are in compliance with all U.S. federal, state, local and foreign
      laws and regulations relating to employment and employment practices, terms
      and
      conditions of employment and wages and hours, except where the failure to be
      in
      compliance could not, individually or in the aggregate, reasonably be expected
      to have a Material Adverse Effect.

     

    
      
        
        

      

      
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    (l)  Compliance.
      Neither
      the Company nor any Subsidiary (i) is in default under or in violation of (and
      no event has occurred that has not been waived that, with notice or lapse of
      time or both, would result in a default by the Company or any Subsidiary under),
      nor has the Company or any Subsidiary received notice of a claim that it is
      in
      default under or that it is in violation of, any indenture, loan or credit
      agreement or any other agreement or instrument to which it is a party or by
      which it or any of its properties is bound (whether or not such default or
      violation has been waived), (ii) is in violation of any order of any court,
      arbitrator or governmental body, or (iii) is or has been in violation of any
      statute, rule or regulation of any governmental authority, including without
      limitation all foreign, federal, state and local laws applicable to its business
      and all such laws that affect the environment, except in each case as could
      not
      have or reasonably be expected to result in a Material Adverse
      Effect.

     

    (m)  Regulatory
      Permits.
      The
      Company and the Subsidiaries possess all certificates, authorizations and
      permits issued by the appropriate federal, state, local or foreign regulatory
      authorities necessary to conduct their respective businesses, except where
      the
      failure to possess such permits could not reasonably be expected to result
      in a
      Material Adverse Effect (“Material
      Permits”),
      and
      neither the Company nor any Subsidiary has received any notice of proceedings
      relating to the revocation or modification of any Material Permit.

     

    (n)  Title
      to Assets.
      The
      Company and the Subsidiaries have good and marketable title in fee simple to
      all
      real property owned by them and good and marketable title in all personal
      property owned by them that is material to the business of the Company and
      the
      Subsidiaries, in each case free and clear of all Liens, except for Liens as
      do
      not materially affect the value of such property and do not materially interfere
      with the use made and proposed to be made of such property by the Company and
      the Subsidiaries and Liens for the payment of federal, state or other taxes,
      the
      payment of which is neither delinquent nor subject to penalties. Any real
      property and facilities held under lease by the Company and the Subsidiaries
      are
      held by them under valid, subsisting and enforceable leases with which the
      Company and the Subsidiaries are in compliance.

     

    (o)  Patents
      and Trademarks.
      The
      Company and the Subsidiaries have, or have rights to use, all patents, patent
      applications, trademarks, trademark applications, service marks, trade names,
      trade secrets, inventions, copyrights, licenses and other intellectual property
      rights and similar rights necessary or material for use in connection with
      their
      respective businesses as described in the SEC Reports and which the failure
      to
      so have could have a Material Adverse Effect (collectively, the “Intellectual
      Property Rights”).
      Neither the Company nor any Subsidiary has received a notice (written or
      otherwise) that any of the Intellectual Property Rights used by the Company
      or
      any Subsidiary violates or infringes upon the rights of any Person. To the
      knowledge of the Company, all such Intellectual Property Rights are enforceable
      and there is no existing infringement by another Person of any of the
      Intellectual Property Rights. The Company and its Subsidiaries have taken
      reasonable security measures to protect the secrecy, confidentiality and value
      of all of their intellectual properties, except where failure to do so could
      not, individually or in the aggregate, reasonably be expected to have a Material
      Adverse Effect.

     

    
      
        
        

      

      
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    (p)  Insurance.
      The
      Company and the Subsidiaries are insured by insurers of recognized financial
      responsibility against such losses and risks and in such amounts as are prudent
      and customary in the businesses in which the Company and the Subsidiaries are
      engaged, including, but not limited to, directors and officers insurance
      coverage at least equal to the aggregate Subscription Amount. Neither the
      Company nor any Subsidiary has any reason to believe that it will not be able
      to
      renew its existing insurance coverage as and when such coverage expires or
      to
      obtain similar coverage from similar insurers as may be necessary to continue
      its business without a significant increase in cost.

     

    (q)  Transactions
      with Affiliates and Employees.
      Except
      as set forth in the SEC Reports, none of the officers or directors of the
      Company and, to the knowledge of the Company, none of the employees of the
      Company is presently a party to any transaction with the Company or any
      Subsidiary (other than for services as employees, officers and directors),
      including any contract, agreement or other arrangement providing for the
      furnishing of services to or by, providing for rental of real or personal
      property to or from, or otherwise requiring payments to or from any officer,
      director or such employee or, to the knowledge of the Company, any entity in
      which any officer, director, or any such employee has a substantial interest
      or
      is an officer, director, trustee or partner, in each case in excess of $60,000
      other than for (i) payment of salary or consulting fees for services rendered,
      (ii) reimbursement for expenses incurred on behalf of the Company and (iii)
      other employee benefits, including stock option agreements under any stock
      option plan of the Company.

     

    (r)  Sarbanes-Oxley;
      Internal Accounting Controls.
      The
      Company is in material compliance with all provisions of the Sarbanes-Oxley
      Act
      of 2002 which are applicable to it as of the Closing Date. The
      Company and the Subsidiaries maintain a system of internal accounting controls
      sufficient to provide reasonable assurance that (i) transactions are executed
      in
      accordance with management’s general or specific authorizations, (ii)
      transactions are recorded as necessary to permit preparation of financial
      statements in conformity with GAAP and to maintain asset accountability, (iii)
      access to assets is permitted only in accordance with management’s general or
      specific authorization, and (iv) the recorded accountability for assets is
      compared with the existing assets at reasonable intervals and appropriate action
      is taken with respect to any differences. The Company has established disclosure
      controls and procedures (as defined in Exchange Act Rules 13a-15(e) and
      15d-15(e)) for the Company and designed such disclosure controls and procedures
      to ensure that information required to be disclosed by the Company in the
      reports it files or submits under the Exchange Act is recorded, processed,
      summarized and reported, within the time periods specified in the Commission’s
      rules and forms. The Company’s certifying officers have evaluated the
      effectiveness of the Company’s disclosure controls and procedures as of the end
      of the period covered by the Company’s most recently filed periodic report under
      the Exchange Act (such date, the “Evaluation
      Date”).
      The
      Company presented in its most recently filed periodic report under the Exchange
      Act the conclusions of the certifying officers about the effectiveness of the
      disclosure controls and procedures based on their evaluations as of the
      Evaluation Date. Since the Evaluation Date, there have been no changes in the
      Company’s internal control over financial reporting (as such term is defined in
      the Exchange Act) that has materially affected, or is reasonably likely to
      materially affect, the Company’s internal control over financial
      reporting.

     

    
      
        
        

      

      
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    (s)  Certain
      Fees.
      All
      brokerage or finder’s fees or commissions that are or will be payable by the
      Company to any broker, financial advisor or consultant, finder, placement agent,
      investment banker, bank or other Person with respect to the transactions
      contemplated by the Transaction Documents are as set forth in the PPM. The
      Subscribers shall have no obligation with respect to any fees or with respect
      to
      any claims made by or on behalf of other Persons for fees of a type contemplated
      in this Section that may be due in connection with the transactions contemplated
      by the Transaction Documents. 

     

    (t)  Private
      Placement.
      Assuming the accuracy of the Subscribers’ representations and warranties set
      forth in the Subscription Agreement, no registration under the Securities Act
      is
      required for the offer and sale of the Securities by the Company to the
      Subscribers as contemplated by the PPM. The issuance and sale of the Securities
      hereunder does not contravene the rules and regulations of the Trading
      Market.

     

    (u)  Investment
      Company.
      The
      Company is not, and is not an Affiliate of, and immediately after receipt of
      payment for the Securities, will not be or be an Affiliate of, an “investment
      company” within the meaning of the Investment Company Act of 1940, as amended.
      The Company shall conduct its business in a manner so that it will not become
      subject to the Investment Company Act of 1940, as amended.

     

    (v)  Registration
      Rights.
      Other
      than each of the Subscribers or as set forth in the PPM, no Person has any
      right
      to cause the Company to effect the registration under the Securities Act of
      any
      securities of the Company.

     

    (w)  Listing
      and Maintenance Requirements.
      The
      Company has not, in the 12 months preceding the date hereof, received notice
      from any Trading Market on which the Common Stock is or has been listed or
      quoted to the effect that the Company is not in compliance with the listing
      or
      maintenance requirements of such Trading Market. The Company is, and has no
      reason to believe that it will not in the foreseeable future continue to be,
      in
      compliance with all such listing and maintenance requirements.

     

    (x)  Application
      of Takeover Protections.
      The
      Company and the Board of Directors have taken all necessary action, if any,
      in
      order to render inapplicable any control share acquisition, business
      combination, poison pill (including any distribution under a rights agreement)
      or other similar anti-takeover provision under the Company’s certificate of
      incorporation (or similar charter documents) or the laws of its state of
      incorporation that is or could become applicable to the Subscribers as a result
      of the Subscribers and the Company fulfilling their obligations or exercising
      their rights under the Transaction Documents, including without limitation
      as a
      result of the Company’s issuance of the Securities and the Subscribers’
ownership of the Securities.

     

    
      
        
        

      

      
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    (y)  Disclosure.
      Except
      with respect to the material terms and conditions of the transactions
      contemplated by the Transaction Documents, the Company confirms that neither
      it
      nor any other Person acting on its behalf has provided any of the Subscribers
      or
      their agents or counsel with any information that it believes constitutes or
      might constitute material, nonpublic information. The Company understands and
      confirms that the Subscribers will rely on the foregoing representation in
      effecting transactions in securities of the Company. Attached hereto as
Schedule
      2.1(y)
      is a
      copy of a substantially final Current Report on Form 8-K (the “Merger
      8-K”)
      that
      the Company will file with the Commission in connection with the Merger on
      or
      prior to the 2nd
      Trading
      Day immediately following the date hereof (which Current Report contains, among
      other information, risk factors concerning the Company and financial statements
      required to be filed therewith). All disclosure furnished by or on behalf of
      the
      Company to the Subscribers regarding the Company, its business and the
      transactions contemplated hereby, including the Disclosure Schedules to this
      Addendum, is true and correct and does not contain any untrue statement of
      a
      material fact or omit to state any material fact necessary in order to make
      the
      statements made therein, in light of the circumstances under which they were
      made, not misleading. The press releases disseminated by the Company during
      the
      twelve months preceding the date of this Agreement taken as a whole do not
      contain any untrue statement of a material fact or omit to state a material
      fact
      required to be stated therein or necessary in order to make the statements
      therein, in light of the circumstances under which they were made and when
      made,
      not misleading. The Company acknowledges and agrees that no Subscriber makes
      or
      has made any representations or warranties with respect to the transactions
      contemplated by the PPM other than those specifically set forth in the
      Subscription Agreement.

     

    (z)  No
      Integrated Offering.
      Assuming
      the accuracy of the Purchasers’ representations and warranties set forth in
      Section 3.2, neither the Company, nor any of its Affiliates, nor any Person
      acting on its or their behalf has, directly or indirectly, made any offers
      or
      sales of any security or solicited any offers to buy any security, under
      circumstances that would cause this offering of the Securities to be integrated
      with prior offerings by the Company for purposes of (i) the Securities Act
      which
      would require the registration of any such securities under the Securities
      Act,
      or (ii) any applicable shareholder approval provisions of any Trading Market
      on
      which any of the securities of the Company are listed or designated. 

     

    (aa)  Solvency.
      Based
      on the consolidated financial condition of the Company as of the Closing Date
      after giving effect to the receipt by the Company of the proceeds from the
      sale
      of the Securities hereunder, (i) the fair saleable value of the Company’s assets
      exceeds the amount that will be required to be paid on or in respect of the
      Company’s existing debts and other liabilities (including known contingent
      liabilities) as they mature, (ii) the Company’s assets do not constitute
      unreasonably small capital to carry on its business as now conducted and as
      proposed to be conducted including its capital needs taking into account the
      particular capital requirements of the business conducted by the Company, and
      projected capital requirements and capital availability thereof, and (iii)
      the
      current cash flow of the Company, together with the proceeds the Company would
      receive, were it to liquidate all of its assets, after taking into account
      all
      anticipated uses of the cash, would be sufficient to pay all amounts on or
      in
      respect of its liabilities when such amounts are required to be paid. The
      Company does not intend to incur debts beyond its ability to pay such debts
      as
      they mature (taking into account the timing and amounts of cash to be payable
      on
      or in respect of its debt). The Company has no knowledge of any facts or
      circumstances which lead it to believe that it will file for reorganization
      or
      liquidation under the bankruptcy or reorganization laws of any jurisdiction
      within one year from the Closing Date. Schedule
      2.1(aa)
      sets
      forth as of the date hereof all outstanding secured and unsecured Indebtedness
      of the Company or any Subsidiary, or for which the Company or any Subsidiary
      has
      commitments. For the purposes of this Addendum, “Indebtedness”
means
      (a) any liabilities for borrowed money or amounts owed in excess of $50,000
      (other than trade accounts payable incurred in the ordinary course of business),
      (b) all guaranties, endorsements and other contingent obligations in respect
      of
      indebtedness of others, whether or not the same are or should be reflected
      in
      the Company’s balance sheet (or the notes thereto), except guaranties by
      endorsement of negotiable instruments for deposit or collection or similar
      transactions in the ordinary course of business; and (c) the present value
      of
      any lease payments
      in excess of $50,000 due under leases required to be capitalized in accordance
      with GAAP. Neither
      the Company nor any Subsidiary is in default with respect to any
      Indebtedness.

     

    
      
        
        

      

      
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    (bb)  Tax
      Status.
      Except
      for matters that would not, individually or in the aggregate, have or reasonably
      be expected to result in a Material Adverse Effect, the Company and each
      Subsidiary has filed all necessary federal, state and foreign income and
      franchise tax returns and has paid or accrued all taxes shown as due thereon,
      and the Company has no knowledge of a tax deficiency which has been asserted
      or
      threatened against the Company or any Subsidiary.

     

    (cc)  No
      General Solicitation.
      Neither
      the Company nor any person acting on behalf of the Company has offered or sold
      any of the Securities by any form of general solicitation or general
      advertising. The Company has offered the Securities for sale only to the
      Subscribers and certain other “accredited investors” within the meaning of Rule
      501 under the Securities Act.

     

    (dd)  Foreign
      Corrupt Practices.
      Neither
      the Company, nor to the knowledge of the Company, any agent or other person
      acting on behalf of the Company, has (i) directly or indirectly, used any funds
      for unlawful contributions, gifts, entertainment or other unlawful expenses
      related to foreign or domestic political activity, (ii) made any unlawful
      payment to foreign or domestic government officials or employees or to any
      foreign or domestic political parties or campaigns from corporate funds, (iii)
      failed to disclose fully any contribution made by the Company (or made by any
      person acting on its behalf of which the Company is aware) which is in violation
      of law, or (iv) violated in any material respect any provision of the Foreign
      Corrupt Practices Act of 1977, as amended.

     

    
      
        
        

      

      
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    (ee)  Accountants.
      The
      Company’s accounting firm is set forth on Schedule
      2.1(ee)
      of the
      Disclosure Schedule. To the knowledge and belief of the Company, such accounting
      firm (i) is a registered public accounting firm as required by the Exchange
      Act
      and (ii) shall express its opinion with respect to the financial statements
      to
      be included in the Company’s Annual Report on Form 10-KSB for the year ending
      December 31, 2006.

     

    (ff)  Seniority.
      As of
      the Closing Date, no Indebtedness or other claim against the Company is senior
      to the Debentures in right of payment, whether with respect to interest or
      upon
      liquidation or dissolution, or otherwise, other than indebtedness secured by
      purchase money security interests (which is senior only as to underlying assets
      covered thereby) and capital lease obligations (which is senior only as to
      the
      property covered thereby).

     

    (gg)  No
      Disagreements with Accountants and Lawyers.
      There
      are no disagreements of any kind presently existing, or reasonably anticipated
      by the Company to arise, between the Company and the accountants and lawyers
      formerly or presently employed by the Company and the Company is current with
      respect to any fees owed to its accountants and lawyers which could affect
      the
      Company’s ability to perform any of its obligations under any of the Transaction
      Documents.

     

    (hh)  Acknowledgment
      Regarding Subscribers’ Purchase of Securities.
      The
      Company acknowledges and agrees that each of the Subscribers is acting solely
      in
      the capacity of an arm’s length purchaser with respect to the Transaction
      Documents and the transactions contemplated thereby. The Company further
      acknowledges that no Purchaser is acting as a financial advisor or fiduciary
      of
      the Company (or in any similar capacity) with respect to the Transaction
      Documents and the transactions contemplated thereby and any advice given by
      any
      Purchaser or any of their respective representatives or agents in connection
      with the Transaction Documents and the transactions contemplated thereby is
      merely incidental to the Subscribers’ purchase of the Securities. The Company
      further represents to each Purchaser that the Company’s decision to enter into
      this Agreement and the other Transaction Documents has been based solely on
      the
      independent evaluation of the transactions contemplated hereby by the Company
      and its representatives.

     

    (ii)  Acknowledgment
      Regarding Subscribers’ Trading Activity.
      Notwithstanding anything in the PPM to the contrary, it is understood and
      acknowledged by the Company that (i) none of the Subscribers has been asked
      to
      agree by the Company, nor has any Purchaser agreed, to desist from purchasing
      or
      selling, long and/or short, securities of the Company, or “derivative”
securities based on securities issued by the Company or to hold the Securities
      for any specified term, (ii) past or future open market or other transactions
      by
      any Purchaser, specifically including, without limitation, Short Sales or
“derivative” transactions, before or after the closing of this or future private
      placement transactions, may negatively impact the market price of the Company’s
      publicly-traded securities, (iii) any Purchaser, and counter-parties in
“derivative” transactions to which any such Purchaser is a party, directly or
      indirectly, may presently have a “short” position in the Common Stock, and (iv)
      each Purchaser shall not be deemed to have any affiliation with or control
      over
      any arm’s length counter-party in any “derivative” transaction. The
      Company further understands and acknowledges that (a) one or more Investors
      may
      engage in hedging activities at various times during the period that the
      Securities are outstanding, including, without limitation, during the periods
      that the value of the Common Stock included in the Units are being determined
      and (b) such hedging activities (if any) could reduce the value of the existing
      stockholders' equity interests in the Company at and after the time that the
      hedging activities are being conducted.  The Company acknowledges that such
      aforementioned hedging activities do not constitute a breach of any of the
      Transaction Documents.

     

    
      
        
        

      

      
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    (jj)  Regulation
      M Compliance. 
      The Company has not, and to its knowledge no one acting on its behalf has,
      (i)
      taken, directly or indirectly, any action designed to cause or to result in
      the
      stabilization or manipulation of the price of any security of the Company to
      facilitate the sale or resale of any of the Securities, (ii) sold, bid for,
      purchased, or paid any compensation for soliciting purchases of, any of the
      securities of the Company or (iii) paid or agreed to pay to any Person any
      compensation for soliciting another to purchase any other securities of the
      Company, other than, in the case of clauses (ii) and (iii), compensation paid
      to
      the Company’s placement agent in connection with the placement of the
      Securities.

     

    2.2 For
      purposes of this Article II, references to the Subsidiaries shall include the
      MST Subsidiary and its business and its direct and indirect subsidiaries, and
      references to all Schedules herein shall mean any and all information and
      disclosures included on the same or equivalent schedule to the Securities
      Purchase Agreement for the Debentures which disclosures are hereby incorporated
      by reference and are not repeated herein; further any and all amendments,
      modifications, waivers, consents, or agreements approved by the Debenture
      purchasers in accordance with the Debentures, with respect to such
      representations and warranties, will be binding upon all beneficiaries of the
      representations and warranties provided in this paragraph without further action
      or consent by any Unit purchasers):

     

    2. Anti
      Dilution Provisions.
      The
      provisions appearing under the heading “III. Covenants By the Company” in the
      Subscription Agreement is deleted and replaced in its entirety with the
      following:

     

    3.1 The
      Company agrees that the Subscriber shall have certain registration rights with
      respect to the shares of Common Stock underlying the Units issued to Subscribers
      pursuant to the terms of the Registration Rights Agreement attached as Exhibit
      C
      to the PPM.

     

    
      
        
        

      

      
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    3.2 For
      a
      period of eighteen (18) months following the Closing Date (the “Adjustment
      Period”),
      in
      the event that the Company sells
      or
      grants any option to purchase or sells or grants any right to reprice, or
      otherwise disposes of or issues (or announces any sale, grant or any option
      to
      purchase or other disposition), any Common Stock or Common Stock Equivalents
      entitling any Person to acquire shares of Common Stock at an effective price
      per
      share that is lower than $0.55
      per
      share (such
      lower price, the “Base Price” and such issuances, collectively, a “Dilutive
      Issuance”)
      (if
      the holder of the Common Stock or Common Stock Equivalents so issued shall
      at
      any time, whether by operation of purchase price adjustments, reset provisions,
      floating conversion, exercise or exchange prices or otherwise, or due to
      warrants, options or rights per share which are issued in connection with such
      issuance, be entitled to receive shares of Common Stock at an effective price
      per share that is lower than $0.55 per share, such issuance shall be deemed
      to
      have occurred for less than the $0.55 per share on such date of the Dilutive
      Issuance), then the Company shall promptly issue additional shares of Common
      Stock to each Subscriber in the Offering in an amount sufficient that the
      subscription price paid by each Subscriber, when divided by the total number
      of
      shares issued (shares included in the purchased Units plus the additional shares
      issued in the Dilutive Issuance), will result in an actual price paid by each
      Subscriber per share of Common Stock equal to the Base Price. Such adjustment
      shall be made whenever such Common Stock or Common Stock Equivalents are issued
      within the Adjustment Period. Notwithstanding the foregoing, no adjustment
      will
      be made under this Section 3.2 in respect of an Exempt Issuance. The Company
      shall notify the purchaser in writing, no later than 1 Business Day following
      the issuance of any Common Stock or Common Stock Equivalents subject to this
      Section, indicating therein the applicable issuance price, or applicable reset
      price, exchange price, conversion price and other pricing terms (such notice,
      the “Dilutive
      Issuance Notice”).
      For
      purposes of clarification, whether or not the Company provides a Dilutive
      Issuance Notice pursuant to this Section 3.2, upon the occurrence of any
      Dilutive Issuance, the purchaser is entitled to receive a number of shares
      based
      upon the Base Price on or after the date of such Dilutive Issuance, regardless
      of whether the purchaser accurately refers to the Base Price in any notice.
      Notwithstanding anything herein or in any related document to the contrary,
      the
      foregoing does not convey to the purchaser any right to participation in any
      future financings or offerings now or in the future contemplated or undertaken
      by the Company.

     

    “Common
      Stock Equivalents”
means
      any securities of the Company or the Subsidiaries which would entitle the holder
      thereof to acquire at any time Common Stock, including, without limitation,
      any
      debt, preferred stock, rights, options, warrants or other instrument that is
      at
      any time convertible into or exercisable or exchangeable for, or otherwise
      entitles the holder thereof to receive, Common Stock.

     

    “Exempt
      Issuance”
means:
      (A) any issuance resulting from the availability or effectiveness of any
      anti-dilution or price protection rights under the Debenture or related to
      the
      Debenture, such as any warrants or purchase agreements); and (B) the issuance
      of: (a) shares of Common Stock or options to employees, officers, directors,
      or
      consultants of the Company pursuant to any stock or option plan duly adopted
      for
      such purpose by a majority of the non-employee members of the Board of Directors
      of the Company or a majority of the members of a committee of non-employee
      directors established (provided, however, any such issuances to consultants
      shall not exceed 750,000 shares of Common Stock and Common Stock Equivalents,
      in
      the aggregate, in any 12 month period), (b) securities upon the exercise or
      exchange of or conversion of any Securities issued hereunder and/or other
      securities exercisable or exchangeable for or convertible into shares of Common
      Stock issued and outstanding on the date of this Agreement,
      provided that such securities have not been amended since the date of this
      Agreement to increase the number of such securities or to decrease the exercise,
      exchange or conversion price of such securities; and (c) securities issued
      pursuant to acquisitions or strategic transactions approved by a majority of
      the
      disinterested directors of the Company, provided that any such issuance shall
      only be to a Person which is either an owner
      of,
      or an entity that is, itself or through its subsidiaries, an operating company
      in a business synergistic with the business of the Company and in which the
      Company receives benefits in addition to the investment of funds, but shall
      not
      include a transaction in which the Company is issuing securities primarily
      for
      the purpose of raising capital or to an entity whose primary business is
      investing in securities.

     

    
      
        
        

      

      
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    3. Legal
      Opinion.
      The
      Company shall deliver or cause to be delivered to each purchaser of Units a
      legal opinion of Haynes and Boone, LLP, counsel to the Company, addressed to
      such purchaser, dated as of the date of closing on the purchase of Units, in
      standard form, covering such matters as are contained in the opinion to be
      delivered to the Debenture purchasers, and subject to the same caveats and
      limitations as set forth in such opinion.

     

    4. Definitions.
      In
      addition to the terms defined elsewhere in this Addendum, the following terms
      have the meanings set forth in this Section 4:

     

    (a) “Affiliate”
means
      any Person that, directly or indirectly through one or more intermediaries,
      controls or is controlled by or is under common control with a Person, as such
      terms are used in and construed under Rule 144 under the Securities Act. With
      respect to a Subscriber, any investment fund or managed account that is managed
      on a discretionary basis by the same investment manager as such Subscriber
      will
      be deemed to be an Affiliate of such Subscriber.

     

    (b) “Commission”
means
      the Securities and Exchange Commission.

     

    (c) “Common
      Stock”
means
      the common stock of the Company, par value $.001 per share, and any other class
      of securities into which such securities may hereafter be reclassified or
      changed into.

     

    (d) “Common
      Stock Equivalents”
means
      any securities of the Company or the Subsidiaries which would entitle the holder
      thereof to acquire at any time Common Stock, including, without limitation,
      any
      debt, preferred stock, rights, options, warrants or other instrument that is
      at
      any time convertible into or exercisable or exchangeable for, or otherwise
      entitles the holder thereof to receive, Common Stock.

     

    (e) “Debentures”
means,
      the 8% Secured Convertible Debentures due April 30, 2010, issued by the Company
      to the purchasers pursuant to that certain Securities Purchase Agreement, dated
      as of May __, 2007, among the Company and each purchaser identified on the
      signature pages thereto.

     

    (f) “Exchange
      Act”
means
      the Securities Exchange Act of 1934, as amended, and the rules and regulations
      promulgated thereunder.

     

    
      
        
        

      

      
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    (g) “Liens”
means
      a
      lien, charge, security interest, encumbrance, right of first refusal, preemptive
      right or other restriction. 

     

    (h) “Merger”
means
      the closing of the acquisition of 100% of the issued and outstanding capital
      stock of the MST Subsidiary by the Company pursuant to that certain Agreement
      of
      Merger and Plan of Reorganization among the Company (f/k/a Fitness Xpress
      Software, Inc.), Microwave Acquisition Corp. and the MSTI Subsidiary, of even
      date herewith. 

     

    (i) “Person”
means
      an individual or corporation, partnership, trust, incorporated or unincorporated
      association, joint venture, limited liability company, joint stock company,
      government (or an agency or subdivision thereof) or other entity of any
      kind.

     

    (j) “Proceeding”
means
      an action, claim, suit, investigation or proceeding (including, without
      limitation, an investigation or partial proceeding, such as a deposition),
      whether commenced or threatened.

     

    (k) “Registration
      Rights Agreement”
means
      the Registration Rights Agreement, dated the date hereof, among the Company
      and
      the Subscribers.

     

    (l) “Registration
      Statement”
means
      a
      registration statement meeting the requirements set forth in the Registration
      Rights Agreement and covering the resale of the Common Stock included in the
      Units by each Subscriber as provided for in the Registration Rights
      Agreement.

     

    (m) “Rule
      144”
means
      Rule 144 promulgated by the Commission pursuant to the Securities Act, as such
      Rule may be amended from time to time, or any similar rule or regulation
      hereafter adopted by the Commission having substantially the same effect as
      such
      Rule.

     

    (n) “Securities”
means
      the Common Stock, the Warrants and the Common Stock included in the
      Units.

     

    (o) “Securities
      Act”
means
      the Securities Act of 1933, as amended, and the rules and regulations
      promulgated hereunder.

     

    (p) “Short
      Sales”
means
      all “short sales” as defined in Rule 200 of Regulation SHO under the Exchange
      Act (but shall not be deemed to include the location and/or reservation of
      borrowable shares of Common Stock). 

     

    (q) “Subscription
      Amount”
means,
      as to each Subscriber, the aggregate amount to be paid for Common Stock and
      Warrants purchased under such Subscriber’s Subscription Agreement in United
      States dollars and in immediately available funds.

     

    (r) “Subsidiary”
means
      any subsidiary of the Company as set forth on Schedule 2.1(a).

     

    (s) “Trading
      Day”
means
      a
      day on which the Common Stock is traded on a Trading Market.

     

    
      
        
        

      

      
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    (t) “Trading
      Market”
means
      the following markets or exchanges on which the Common Stock is listed or quoted
      for trading: the American Stock Exchange, the Nasdaq Capital Market, the Nasdaq
      Global Market, the Nasdaq Global Select Market, the New York Stock Exchange
      or
      the OTC Bulletin Board.

     

    (u) “Transaction
      Documents”
means
      the Subscription Agreements, the Warrants, the Registration Rights Agreement,
      all exhibits and schedules hereto and thereto and any other documents or
      agreements executed in connection with the transactions contemplated
      thereunder.

     

    (v) “Warrants”
means
      collectively the Common Stock purchase warrants delivered to the Subscribers
      in
      accordance with the Subscription Agreements and the PPM.

     

    IN
      WITNESS WHEREOF, the Company has executed this Addendum as of the
      ___th
      day of
      May 2007.

     

    
      	 	 	 
	 	
              MSTI
                Holdings, Inc.

            
	 
 	 
 	 
 
	
            	By:  	
            
	 	
              

              Name:
                Frank Matarazzo

              
                Title:
                  Chief Executive Officer

              

            


    

     

    
      
        
        

      

      
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