Exhibit
        10.1

    

     

    

    


    March
      1,
      2007

    


    


    BY
      FACSIMILE

    


    [Name
      of
      Holder]

    [Address
      of Holder]

    Attention:

    


    


    
      	 	
              Re:

            	
              Amendment
                to Unsecured Convertible Debentures of Millennium Cell
                Inc.

            


    

    


    Ladies
      and Gentlemen:

    


    1. 
      Reference is made to the Convertible Debentures of Millennium Cell Inc. (the
      “Company”)
      with
      an Original Issue Date of February 16, 2007 in the aggregate principal amount
      of
      $6,000,000 (the “Debentures”).
      Capitalized terms used but not defined herein shall have the meanings given
      to
      such terms in the Debentures.

    


    2. 
      Effective upon execution and delivery to the Company by the Majority Holders
      of
      signed counterparts to letters identical to this letter (the “Amendment
      Effective Time”),
      the
      Debentures shall be amended as follows:

    


    Section
      7(d) of the Debentures is hereby amended and restated in its entirety as
      follows:

    


    “(d)
      Restricted
      Payments.
      The
      Company shall not, and the Company shall not permit any of its Subsidiaries
      to,
      directly or indirectly, redeem, defease, repurchase, repay or make any payments
      in respect of, by the payment of cash or cash equivalents (in whole or in part,
      whether by way of open market purchases, tender offers, private transactions
      or
      otherwise), all or any portion of any Permitted Indebtedness (other than this
      Debenture, the Other Debentures and, subject to the limitations set forth in
      clause (iv) of the definition of Permitted Indebtedness in Section 1 hereof,
      any
      payment of interest or principal in respect of Permitted Pari Passu
      Indebtedness; provided,
      however,
      that
      any such payment of principal of Permitted Pari Passu Indebtedness shall be
      treated for purposes of Section 6(e) of this Debenture as if such Permitted
      Pari
      Passu Indebtedness constitutes “Other Debentures” hereunder and the Company
      shall comply with Section 6(e) of this Debenture in connection therewith,
mutatis
      mutandis, including,
      without limitation, providing that any payment with respect to any redemption
      of
      this Debenture, any Other Debentures and any principal payment in respect of
      such Permitted Pari Passu Indebtedness shall be made pro rata among the Holder,
      each holder of Other Debentures and each holder of such Permitted Pari Passu
      Indebtedness, in each case based on the principal amount of such Indebtedness),
      whether by way of payment in respect of principal of (or premium, if any) or
      interest on such Indebtedness, if at the time such payment is due or is
      otherwise made or, after giving effect to such payment, an event constituting,
      or that with the passage of time and without being cured would constitute,
      an
      Event of Default has occurred and is continuing.”

    


    
      
         

      

      
         

        
          

        

      

      
         

      

    

     

    3.
      As
      amended hereby, the Debentures shall remain in full force and
      effect.

    


    4.
      On or
      before 8:30 a.m., New York City time, on the first Business Day following the
      Amendment Effective Time, the Company shall file a Current Report on Form 8-K
      describing the terms of this amendment in the form required by the 1934 Act
      and
      attaching the form of this letter agreement as an exhibit to such filing (the
      “8-K
      Filing”).
      From
      and after the filing of the 8-K Filing with the SEC, no Buyer shall be in
      possession of any material, nonpublic information received from the Company,
      any
      of its Subsidiaries or any of its respective officers, directors, employees
      or
      agents, that is not disclosed in the 8-K Filing.

    


    5.
      This
      letter agreement may be executed in one or more counterparts, each of which,
      when executed and delivered, shall be deemed to be an original, but all of
      which
      when taken together shall constitute one and the same instrument. This letter
      agreement may be executed by facsimile, which shall be binding to the same
      extent as an original signature page. 

    


    6. 
      The
      obligations of each Buyer under any Transaction Document are several and not
      joint with the obligations of any other Buyer, and no Buyer shall be responsible
      in any way for the performance of the obligations of any other Buyer under
      any
      Transaction Document. Nothing contained herein or in any other Transaction
      Document, and no action taken by any Buyer pursuant hereto or thereto, shall
      be
      deemed to constitute the Buyers as a partnership, an association, a joint
      venture or any other kind of entity, or create a presumption that the Buyers
      are
      in any way acting in concert or as a group with respect to such obligations
      or
      the transactions contemplated by the Transaction Documents. Each Buyer confirms
      that it has independently participated in the negotiation of the transaction
      contemplated hereby with the advice of its own counsel and advisors. Each Buyer,
      other than Portside Growth & Opportunity Fund, acknowledges that (i) Schulte
      Roth & Zabel LLP solely represented Portside Growth & Opportunity Fund
      in connection with the transaction contemplated hereby and (ii) Portside Growth
      & Opportunity Fund did not provide any advice in connection herewith and
      such Buyer's determination to participate herein was based solely on its own
      evaluation of the risks and merits of the investment contemplated hereby. Each
      Buyer shall be entitled to independently protect and enforce its rights,
      including, without limitation, the rights arising out of this Amendment or
      out
      of any other Transaction Documents, and it shall not be necessary for any other
      Buyer to be joined as an additional party in any proceeding for such
      purpose.

    


    
      
         

      

      
        2

        
          

        

      

      
         

      

    

     

    7.
      All
      questions concerning the construction, validity, enforcement and interpretation
      of this letter agreement shall be governed by the internal laws of the State
      of
      New York, without giving effect to any choice of law or conflict of law
      provision or rule (whether of the State of New York or any other jurisdictions)
      that would cause the application of the laws of any jurisdictions other than
      the
      State of New York. Each party hereby irrevocably submits to the exclusive
      jurisdiction of the state and federal courts sitting in The City of New York,
      Borough of Manhattan, for the adjudication of any dispute hereunder or in
      connection herewith or with any transaction contemplated hereby or discussed
      herein, and hereby irrevocably waives, and agrees not to assert in any suit,
      action or proceeding, any claim that it is not personally subject to the
      jurisdiction of any such court, that such suit, action or proceeding is brought
      in an inconvenient forum or that the venue of such suit, action or proceeding
      is
      improper. Each party hereby irrevocably waives personal service of process
      and
      consents to process being served in any such suit, action or proceeding by
      mailing a copy thereof to such party at the address for such notices to it
      under
      this letter agreement and agrees that such service shall constitute good and
      sufficient service of process and notice thereof. Nothing contained herein
      shall
      be deemed to limit in any way any right to serve process in any manner permitted
      by law. If any provision of this letter agreement shall be invalid or
      unenforceable in any jurisdiction, such invalidity or unenforceability shall
      not
      affect the validity or enforceability of the remainder of this letter agreement
      in that jurisdiction or the validity or enforceability of any provision of
      this
      letter agreement in any other jurisdiction. EACH
      PARTY HEREBY IRREVOCABLY WAIVES ANY RIGHT IT MAY HAVE, AND AGREES NOT TO
      REQUEST, A JURY TRIAL FOR THE ADJUDICATION OF ANY DISPUTE HEREUNDER OR IN
      CONNECTION WITH OR ARISING OUT OF THIS LETTER AGREEMENT OR ANY TRANSACTION
      CONTEMPLATED HEREBY.

     

    
      	 	 	 
	 	Very truly yours, 
	 	 
	 	MILLENNIUM
              CELL INC.
	 
 	 
 	 
 
	 	By:  	/s/ John
              Giolli 
	 	
              
Name:
              John Giolli
	 	
              Title:
                Chief Financial Officer 

            


    

    


    
      	ACKNOWLEDGED AND
              AGREED
              TO:	 	 	 
	 	 	 	 	 
	PORTSIDE GROWTH & OPPORTUNITY
              FUND	 	 	 
	 	 	 	 	 
	By:  	/s/ Jeffrey
              C. Smith	 	 	 
	 	
              
Name:
              Jeffrey C. Smith	 	 	
            
	 	Title:
              Authorized
              Signatory	 	 	 


    

     

    
      
         

      

      
        3

        
          

        

      

      
         

      

    

     

    
      
        	ACKNOWLEDGED
                AND AGREED
                TO:	 	 	 
	 	 	 	 	 
	GEMNINI MASTER FUND, LTD.	 	 	 
	 	 	 	 	 
	By:  	/s/ Steven
                W.
                Winters	 	 	 
	 	
                
Name:
                Steven W. Winters	 	 	
              
	 	Title:
                President
                of the Investment Manager	 	 	 


      

       

      
        
           

        

        
          4

          
            

          

        

        
           


      

    

    
       

      
        
          	ACKNOWLEDGED
                  AND AGREED
                  TO:	 	 	 
	 	 	 	 	 
	JGB CAPITAL L.P.	 	 	 
	 	 	 	 	 
	By:  	/s/ Brett
                  Cohen	 	 	 
	 	
                  
Name:
                  Brett Cohen	 	 	
                
	 	Title:
                  President	 	 	 


        

         

        
          
             

          

          
            5

            
              

            

          

          
             


        

      

    

    
       

      
        
          	ACKNOWLEDGED
                  AND AGREED
                  TO:	 	 	 
	 	 	 	 	 
	JGB CAPITAL OFFSHORE,
                  LTD.	 	 	 
	 	 	 	 	 
	By:  	/s/ Brett
                  Cohen	 	 	 
	 	
                  
Name:
                  Brett Cohen	 	 	
                
	 	Title:
                  President	 	 	 


        

         

        
          
             

          

          
            6

            
              

            

          

          
             

          


        
           

          
            
              	ACKNOWLEDGED
                      AND AGREED
                      TO:	 	 	 
	 	 	 	 	 
	THE TAIL WIND FUND
                      LTD.	 	 	 
	By: TAIL WIND ADVISORY
                      AND
                      MANAGEMENT LTD., as investment manager	 	 	 
	 	 	 	 	 
	By:  	/s/ David
                      A.
                      Crook	 	 	 
	 	
                      
Name:
                      David A. Crook	 	 	
                    
	 	Title:
                      CEO	 	 	 


            

             

            
              
                 

              

              
                7

                
                  

                

              

              
                 

              

            

          

        

        
           

          
            
              	ACKNOWLEDGED
                      AND AGREED
                      TO:	 	 	 
	 	 	 	 	 
	SOLOMON STRATEGIC
                      HOLDINGS,
                      INC.	 	 	 
	 	 	 	 	 
	By:  	/s/ A.
                      P.
                      Mackellar	 	 	 
	 	
                      
Name:
                      A. P. Mackellar	 	 	
                    
	 	Title:
                      Director	 	 	 


            

             

            
              
                 

              

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