EXECUTION
COPY

     

    AMENDMENT
NO. 3 TO

     

    STOCK
PURCHASE AGREEMENT

     

    This
Amendment No. 3 (this “Amendment”), dated
December 18, 2008, to the Stock Purchase Agreement (as defined below) is made by
and among Vector Intersect Security Acquisition Corporation, a Delaware
corporation (“Parent”), Cyalume
Acquisition Corp., a Delaware corporation (“Purchaser”), Cyalume
Technologies, Inc., a Delaware corporation (the “Company”), and GMS
Acquisition Partners Holdings, LLC (“Seller”).  Any
capitalized term not defined herein shall have the meaning for such term
specified in the Stock Purchase Agreement.

     

    WHEREAS, Parent, Purchaser,
the Company and Seller entered into a Stock Purchase Agreement dated February
14, 2008, Amendment No. 1 to the Stock Purchase Agreement on October 22, 2008,
and Amendment No. 2 to the Stock Purchase Agreement on December 17, 2008 (as
amended, the “Stock
Purchase Agreement”);

     

    NOW THEREFORE, in
consideration of the foregoing and the representations, warranties, covenants
and agreements herein contained and other good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the parties hereto
hereby agree as follows:

     

    1. The text
of Section 2.4(e) of the Stock Purchase Agreement is hereby deleted in its
entirety and replaced with the following:

     

    “Adjustment
to Estimated Purchase Price.

     

    (i)           If
the Actual Adjustment is a positive amount, Parent shall promptly pay the amount
of the Actual Adjustment by issuing shares of Parent Common Stock, with an
aggregate value (based on the Average Trading Price as of the date of
determination of the Actual Adjustment) equal to the Actual Adjustment plus 12,314 shares of
Parent Common Stock, to those Members who held Common Units as of the Closing
Date (on a pro rata basis based on the number of Common Units held by each
Member as of immediately prior to the Closing), as set forth in a written notice
by Seller or Cova.

     

    (ii)           If
the Actual Adjustment is a negative amount, then Seller or Cova shall promptly
pay Parent the amount of the Actual Adjustment by instructing the Escrow Agent
to deliver to Parent such number of shares of Escrowed Stock that has an
aggregate value (based on the Average Trading Price as of the date of
determination of the Actual Adjustment) equal to the Actual Adjustment (the
“Negative Adjustment
Shares”) less 12,314 shares of
Parent Common Stock; provided, that if the
number of shares of Parent Common Stock payable to Parent under this Section 2.4(e)(ii) is
less than 12,314, then Parent shall promptly issue to those Members who held
Common Units as of the Closing Date (on a pro rata basis based on the number of
Common Units held by each Member as of immediately prior to the Closing), as set
forth in a written notice by Seller or Cova, an aggregate number of shares of
Parent Common Stock equal to (A) 12,314 less (B) the Negative
Adjustment Shares.”

     

    
      
         

      

      
         

        
          

        

      

      
         

      

    

     

    2. The text
of the last paragraph in Section 6.1 of the Stock Purchase Agreement is hereby
deleted in its entirety and replaced with the following:

     

    “Nothing
in this Agreement shall prevent, or be construed to prevent, Seller or the
Company from using cash and/or cash equivalents of the Company or any of its
Subsidiaries as Seller or the Company deems fit (including by causing the
distribution by any of the foregoing Persons of such cash and/or cash
equivalents to Seller or to any other Person or the repayment of Indebtedness of
the Company or its Subsidiaries); provided, that it is
understood that any cash remaining at Closing will be for the benefit of the
Purchaser and the Parent, and neither the Purchaser nor the Parent shall have
any claim to receive any additional amounts from the Company, the Seller or the
Members (other than (1) indemnification for any Losses pursuant to the
provisions of Article XI hereof, and (2) the Net Working Capital Adjustment, if
any) and (ii) any such use of the cash or cash equivalents by Seller or the
Company shall not affect the Company’s and the Seller’s obligations hereunder
with respect to, and such use of cash and cash equivalents shall be deemed to
occur immediately prior to Closing for purposes of calculating, the Net Working
Capital Adjustment, if any.  For the avoidance of doubt, all cash and
cash equivalents of the Company and its Subsidiaries remaining at Closing, shall
be included in the calculation of the Net Working Capital, as adjusted; provided, that loans
made to the Company by Affiliates of  Parent on or about the Closing
Date shall not be included in the calculation of Net Working
Capital.”

     

    3. The
Amendment set forth herein is limited precisely as written and shall not be
deemed to be an amendment of any other term or condition of the Stock Purchase
Agreement or any of the documents referred to therein.  Whenever the
Stock Purchase Agreement is referred to in any agreement, document or
instrument, such reference shall be to the Stock Purchase Agreement as amended
hereby.  Except as expressly amended hereby, the terms and conditions
of the Stock Purchase Agreement shall continue in full force and
effect.

     

    4. This
Amendment may be signed in any number of counterparts, each of which shall be an
original and all of which shall be deemed to be one and the same instrument,
with the same effect as if the signatures thereto and hereto were upon the same
instrument.  A facsimile signature shall be deemed to be an original
signature for purposes of this Amendment.

     

    5. This
Amendment is intended to be in full compliance with the requirements for an
Amendment to the Stock Purchase Agreement as required by Section 14.2 of the
Stock Purchase Agreement, and every defect in fulfilling such requirements for
an effective amendment to the Stock Purchase Agreement is hereby ratified,
intentionally waived and relinquished by all parties hereto.

    


    
      
         

      

      
        2

        
          

        

      

      
         

      

    

     

    IN WITNESS WHEREOF, the
parties hereto have duly executed this Amendment No.2 to the Stock Purchase
Agreement as of the day and year first above written.

    


    
      
        
          
            
              
                
                  
                    	 
      	
                            VECTOR
      INTERSECT ACQUISITION

                          
	 
      	CORP.
	 	 
	 
      	
                            By:

                          	 
      
	 
      	 
      	
                            Name:

                          
	 
      	 
      	
                            Title:

                          
	 
      	 
      	 
      
	 
      	
                            CYALUME
      ACQUISITION CORP.

                          
	 
      	 
      	 
      
	 
      	
                            By:

                          	 
       
	 
      	 
      	
                            Name:

                          
	 
      	 
      	
                            Title:

                          
	 
      	 
      	 
      
	 
      	
                            CYALUME
      TECHNOLOGIES, INC.

                          
	 
      	 
      	 
      
	 
      	
                            By:

                          	 
       
	 
      	 
      	
                            Name:

                          
	 
      	 
      	
                            Title:

                          
	 
      	 
      	 
      
	 
      	
                            GMS
      ACQUISITION PARTNERS HOLDINGS, LLC

                          
	 
      	 
      	 
      
	 
      	
                            By:

                          	 
       
	 
      	 
      	
                            Name:

                          
	 
      	 
      	
                            Title: