PROMISSORY NOTE 
 
$20,000,000.00
Houston, Texas
June 16, 2006,
effective as of March 31, 2006

 
FOR VALUE RECEIVED and WITHOUT GRACE, the undersigned (“Makers”) jointly and
severally promise to pay to the order of STERLING BANK (“Payee”), at its banking
quarters in Houston, Harris County, Texas, the sum of TWENTY MILLION DOLLARS
($20,000,000.00), or so much thereof as may be advanced against this Note
pursuant to the Amended and Restated Credit Agreement dated of even date
herewith by and between Makers and Payee (as amended, restated or supplemented
from time to time, the “Credit Agreement”), together with interest at the rates
and calculated as provided in the Credit Agreement.
 
Reference is hereby made to the Credit Agreement for matters governed thereby,
including, without limitation, the availability of Makers to receive advances
under this Note and certain events which will entitle the holder hereof to
accelerate the maturity of all amounts due hereunder. Capitalized terms used but
not defined in this Note shall have the meanings assigned to such terms in the
Credit Agreement.
 
This Note is issued pursuant to and is payable as provided in the Credit
Agreement. Subject to compliance with applicable provisions of the Credit
Agreement, Makers may at any time pay the full amount or any part of this Note
without the payment of any premium or fee, but such payment shall not, until
this Note is fully paid and satisfied, excuse the payment as it becomes due of
any payment on this Note provided for in the Credit Agreement.
 
Without being limited thereto or thereby, this Note is secured by the Security
Instruments.
 
THIS NOTE SHALL BE GOVERNED AND CONTROLLED BY THE LAWS OF THE STATE OF TEXAS
WITHOUT GIVING EFFECT TO PRINCIPLES THEREOF RELATING TO CONFLICTS OF LAW;
PROVIDED, HOWEVER, THAT CHAPTER 345 OF THE TEXAS FINANCE CODE (WHICH REGULATES
CERTAIN REVOLVING CREDIT LOAN ACCOUNTS AND REVOLVING TRIPARTY ACCOUNTS) SHALL
NOT APPLY TO THIS NOTE.
 

       
MAKERS:
 

UNITED HERITAGE CORPORATION
 
   
   
    By:   /s/ C. Scott Wilson  

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C. Scott Wilson  
Chief Executive Officer and President

 

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LOTHIAN OIL INC.
 
 
 
 
By:  
/s/ C. Scott Wilson
 

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C. Scott Wilson
 
Chief Financial Officer

 

       
LOTHIAN OIL (USA) INC.
       
By:
/s/ C. Scott Wilson
   

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C. Scott Wilson
   
Chief Financial Officer

       
LOTHIAN OIL TEXAS I, INC.
       
By:
/s/ C. Scott Wilson
   

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C. Scott Wilson
   
Chief Financial Officer

       
UHC NEW MEXICO CORPORATION
       
By:
/s/ C. Scott Wilson
   

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C. Scott Wilson,
   
Chief Executive Officer and President

 

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STATE OF TEXAS
§
   
§
 
COUNTY OF HARRIS
§
 

 
 
This instrument was acknowledged before me on the 16th day of June 2006, by
Daniel G. Steele, Senior Vice President, of Sterling Bank, a Texas state
chartered banking institution, on behalf of said banking institution.
 

              /s/ Rhonda Muschalik  

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NOTARY PUBLIC, STATE OF TEXAS    

THE STATE OF TEXAS
§
   
§
 
COUNTY OF HARRIS
§
 

 
This instrument was acknowledged before me on this 15th day of June 2006, by C.
Scott Wilson, Chief Executive Officer and President of United Heritage
Corporation, a Utah corporation, on behalf of said corporation.
 

               
/s/ Rhonda Muschalik
   

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NOTARY PUBLIC, STATE OF TEXAS
     

THE STATE OF TEXAS
§
   
§
 
COUNTY OF HARRIS
§
 

 
This instrument was acknowledged before me on this 15th day of June 2006, by C.
Scott Wilson, Chief Financial Officer of Lothian Oil Inc., a Delaware
corporation, on behalf of said corporation.
 

               
/s/ Rhonda Muschalik
   

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NOTARY PUBLIC, STATE OF TEXAS
     

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THE STATE OF TEXAS
§
   
§
 
COUNTY OF HARRIS
§
 

This instrument was acknowledged before me on this 15th day of June 2006, by
C. Scott Wilson, Chief Financial Officer of Lothian Oil (USA) Inc., a Texas
corporation, on behalf of said corporation.
 

         
/s/ Rhonda Muschalik
   

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NOTARY PUBLIC, STATE OF TEXAS
     

 
THE STATE OF TEXAS
§
   
§
 
COUNTY OF HARRIS
§
 

 
This instrument was acknowledged before me on this 15th day of June 2006, by C.
Scott Wilson, Chief Financial Officer of Lothian Oil Texas I, Inc., a Texas
corporation, on behalf of said corporation.

               
/s/ Rhonda Muschalik
   

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NOTARY PUBLIC, STATE OF TEXAS
     

THE STATE OF TEXAS
§
   
§
 
COUNTY OF HARRIS
§
 

This instrument was acknowledged before me on this 15th day of June 2006, by C.
Scott Wilson, President and Chief Executive Officer of UHC New Mexico
Corporation, a New Mexico corporation, on behalf of said corporation.
 

         
/s/ Rhonda Muschalik
   

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NOTARY PUBLIC, STATE OF TEXAS