Unassociated Document


    March 13,
2009

    


    Tremisis
Energy Acquisition Corporation II

    2925
Briarpark, Suite 150-A

    Houston,
TX 77042

    


    Gentlemen:

    


    The
undersigned, as a condition to the consummation of the transactions contemplated
by that certain agreement (the “Put/Call Agreement”), dated
the date hereof, by and among Tremisis Energy Acquisition Corporation II (“Company”), Lawrence S. Coben,
Ronald D. Ormand, Jon Schotz, Charles A. Norris, Stephen N. Casati, Bill
Goldstein, Dean Vanech, Olympus Capital Investment, LLC, Jerry Doren, Owen
Coleman, Bill Armstrong, Trevor Wilson, Brian McInerney, Richard Kassar, David
Levine, Jim Land, David A. Preiser, Gary C. Evans, Jonathan Jacobs
(collectively, the “Sellers”), Sang-Chul Kim and
SoftForum Co., Ltd., hereby agrees as follows (certain capitalized terms used
herein are defined in paragraph 11 hereof):

    


    1.           In
the event that the Company fails to consummate a Business Combination within 24
months from the effective date (“Effective Date”) of the
registration statement relating to the Company’s initial public offering of
securities (“IPO”), the
undersigned will (i) cause the trust fund established in connection with the
Company’s IPO (the “Trust
Fund”) to be liquidated and distributed to the holders of IPO Shares and
(ii) take all reasonable actions within the undersigned’s power to cause the
Company to liquidate as soon as reasonably practicable. The undersigned hereby
waives any and all right, title, interest or claim of any kind in or to any
distribution of the Trust Fund and any remaining net assets of the Company as a
result of such liquidation (“Claim”) and hereby waives any
Claim the undersigned may have in the future as a result of, or arising out of,
any contracts or agreements with the Company and will not seek recourse against
the Trust Fund for any reason whatsoever.

    


    2.           In
order to minimize potential conflicts of interest that may arise from multiple
affiliations, the undersigned agrees to present to the Company for its
consideration, prior to presentation to any other person or entity, any suitable
opportunity to acquire an operating business, until the earlier of the
consummation by the Company of a Business Combination, the liquidation of the
Company or until such time as the undersigned ceases to be an officer or
director of the Company, subject to any pre-existing fiduciary and contractual
obligations the undersigned might have.

    


    3.           The
undersigned acknowledges and agrees that the Company will not consummate any
Business Combination that involves a company that is affiliated with any of the
Insiders unless the Company obtains an opinion from an independent investment
banking firm reasonably acceptable to Merrill Lynch, Pierce, Fenner & Smith
Incorporated, as representative of the underwriters of the Company’s IPO, that
the Business Combination is fair to the Company’s stockholders from a financial
perspective.

    


    4.           Neither
the undersigned, any member of the family of the undersigned, nor any affiliate
(“Affiliate”) of the
undersigned will be entitled to receive and will not accept any compensation for
services rendered to the Company prior to or in connection with the consummation
of the Business Combination; provided that the undersigned
shall be entitled to reimbursement from the Company for the undersigned’s
out-of-pocket expenses incurred in connection with seeking and consummating a
Business Combination.


    
      
         


      

      
         


        
          

        

      

      
         


      

    

    


    5.           
Neither the undersigned, any member of the family of the undersigned, nor any
Affiliate of the undersigned will be entitled to receive or accept a finder’s
fee or any other compensation in the event the undersigned, any member of the
family of the undersigned or any Affiliate of the undersigned originates a
Business Combination.

    


    6.           
The undersigned acknowledges and agrees that any Insider Shares that may be
transferred to the undersigned upon consummation of a Business Combination
pursuant to the Put/Call Agreement will continue to be held in escrow until one
year after the consummation by the Company of such Business Combination, subject
to the terms of that certain Stock Escrow Agreement, dated as of December 6,
2007 by and among the Company, the Sellers and Continental Stock Transfer &
Trust Company.

    


    7.           
The undersigned agrees to be a Director of the Company until the earlier of the
consummation by the Company of a Business Combination or the liquidation of the
Company. The undersigned’s biographical information furnished to the Company and
the Underwriters and attached hereto as Exhibit A is true and
accurate in all respects, does not omit any material information with respect to
the undersigned’s background and contains all of the information required to be
disclosed pursuant to Item 401 of Regulation S-K, promulgated under the
Securities Act of 1933. The undersigned represents and warrants
that:

    


    (a)           the
undersigned is not subject to, or a respondent in, any legal action for, any
injunction, cease-and-desist order or order or stipulation to desist or refrain
from any act or practice relating to the offering of securities in any
jurisdiction;

    


    (b)           the
undersigned has never been convicted of or pleaded guilty to any crime (i)
involving any fraud or (ii) relating to any financial transaction or handling of
funds of another person, or (iii) pertaining to any dealings in any securities
and the undersigned is not currently a defendant in any such criminal
proceeding; and

    


    (c)           the
undersigned has never been suspended or expelled from membership in any
securities or commodities exchange or association or had a securities or
commodities license or registration denied, suspended or revoked.

    


    8.           
The undersigned has full right and power, without violating any agreement by
which the undersigned is bound, to enter into this letter agreement and to serve
as a Director of the Company.

    


    9.           
The undersigned hereby waives the undersigned’s right to exercise conversion
rights with respect to any shares of the Company’s common stock owned or to be
owned by the undersigned, directly or indirectly, and agrees that the
undersigned will not seek conversion with respect to such shares in connection
with any vote to approve a Business Combination.

    


    10.          This
letter agreement may not be amended or modified without the prior consent of
Ronald D. Ormand, as representative of the Sellers. This letter agreement shall
be governed by and construed and enforced in accordance with the laws of the
State of New York, without giving effect to conflicts of law principles that
would result in the application of the substantive laws of another jurisdiction.
The undersigned hereby (i) agrees that any action, proceeding or claim against
him arising out of or relating in any way to this letter agreement (a “Proceeding”) shall be brought
and enforced in the courts of the State of New York of the United States of
America for the Southern District of New York, and irrevocably submits to such
jurisdiction, which jurisdiction shall be exclusive, (ii) waives any objection
to such exclusive jurisdiction and that such courts represent an inconvenient
forum and (iii) irrevocably agrees to appoint Mintz, Levin, Cohn, Ferris,
Glovsky and Popeo, P.C. as agent for the service of process in the State of New
York to receive, for the undersigned and on the undersigned’s behalf, service of
process in any Proceeding. If for any reason such agent is unable to act as
such, the undersigned will promptly notify the Company and the Underwriters and
appoint a substitute agent acceptable to the Company within 30 days and nothing
in this letter agreement will affect the right of either party to serve process
in any other manner permitted by law.


    
      
         


      

      
         


        
          

        

      

      
         


      

    

    


    11.           As
used herein, (i) a “Business
Combination” shall mean an acquisition by merger, capital stock exchange,
asset or stock acquisition, reorganization or otherwise, of an operating
business; (ii) “Insiders” shall mean all
former and current officers and directors of the Company and all stockholders of
the Company that acquired shares of Common Stock of the Company prior to the
IPO, or, if after the IPO, in a private transfer from another former or current
officer or director of the Company, or from a stockholder that purchased such
shares of Common Stock prior to the IPO; (iii) “Insider Shares” shall mean all
of the shares of Common Stock of the Company acquired by an Insider prior to the
IPO or, if acquired after the IPO, in a private transfer from another Insider;
and (iv) “IPO Shares”
shall mean the shares of Common Stock issued in the Company’s IPO.

    


    
      
        
          	/s/
      David
      Jin Yoo  
	
                  David
      Jin Yoo