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| Delaware                                  | 75-2274633          |
|-------------------------------------------|---------------------|
| (State or other jurisdiction              | (I.R.S. Employer    |
| of incorporation or organization)         | Identification No.) |
|                                      |                |
| 6 Desta Drive, Suite 6500, Midland, Texas | 79705               |
| (Address of principal executive office)   | (Zip Code)          |

| Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.                                                                                                                                                                                                                                    | ¨ Yes | x No      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------|-----------|
|                                                                                                                                                                                                                                                                                                                                                       |       |      |
| Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.                                                                                                                                                                                                                               | ¨ Yes | x No      |
|                                                                                                                                                                                                                                                                                                                                                       |       |      |
| Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.   | x Yes      | ¨ No |
|                                                                                                                                                                                                                                                                                                                                                       |       |      |
| Indicate by check mark whether the registrant has submitted electronically and posted on its corporate website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). | ¨ Yes | ¨ No |

| Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.x |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, or a non-accelerated filer.  See definition of “accelerated filer and large accelerated filer” in Rule 12b-2 of the Exchange Act. |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Large accelerated filer ¨                                                                                                                                                                                                                            |   | Accelerated filer ¨ |   | Non-accelerated filer  x |   | Smaller reporting company¨ |   |

| Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). | ¨ Yes | x No |
|---------------------------------------------------------------------------------------------------------|------------|------|

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|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | Page   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------|
| Part I                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 1.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Business                                                                                                                                                    | 3      |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 1A.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Risk Factors                                                                                                                                                | 7      |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 1B.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Unresolved Staff Comments                                                                                                                                   | 9      |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 2.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Properties                                                                                                                                                  | 9      |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 3.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Legal Proceedings                                                                                                                                           | 10     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 4.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Submission of Matters to a Vote of Security Holders                                                                                                         | 10     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Part II                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 5.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Market for Registrant's Common Equity, Related                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |   |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | Stockholder Matters and Issuer Purchases of Equity Securities                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | 11     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 6.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Selected Financial Data                                                                                                                                     | 12     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 7.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Management's Discussion and Analysis of                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |   |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | Financial Condition and Results of Operations                                                                                                                                   | 13     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 7A.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Quantitative and Qualitative Disclosures About Market Risk                                                                                                  | 15     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 8.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Financial Statements and Supplementary Data                                                                                                                 | 16     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 9.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Changes in and Disagreements with Accountants                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |   |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | on Accounting and Financial Disclosure                                                                                                                                          | 29     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 9A.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Controls and Procedures                                                                                                                                     | 29     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 9B.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Other Information                                                                                                                                           | 30     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Part III                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 10.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Directors, Executive Officers and Corporate Governance                                                                                                      | 31     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 11.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Executive Compensation                                                                                                                                      | 31     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 12.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Security Ownership of Certain Beneficial Owners and Management and                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |   |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | Related Stockholder Matters                                                                                                                                                     | 32     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 13.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Certain Relationships and Related Transactions, and Director Independence                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 32     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 14.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Principal Accounting Fees and Services                                                                                                                      | 32     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Part IV                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Item 15.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Exhibits and Financial Statement Schedules                                                                                                                  | 33     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Glossary of Oil and Gas Terms                                                                                                                   | 34                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
| Signatures                                                                                                                                      | 36                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |

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| ·   | amends the definition of proved reserves to require the use of average commodity prices based upon the prior 12 month period rather than year-end prices; |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | expands the type of technologies available to establish reserve estimates and categories; |
|--------------------|-------------------------------------------------------------------------------------------|

| ·   | modifies certain definitions used in estimating proved reserves; |
|--------------------|------------------------------------------------------------------|

| ·   | permits disclosure of probable and possible reserves; and |
|--------------------|-----------------------------------------------------------|

| ·   | permits disclosure of reserves based on different price and cost criteria, such as futures prices or management forecasts. |
|--------------------|----------------------------------------------------------------------------------------------------------------------------|

|                               |   | Proved Developed |    |   | Proved       |   |   | Total       |   |
|------------------------------------|--------|------------------|---------|--------|--------------|--------|--------|-------------|--------|
|                               |   | Producing        |    |   | Nonproducing |   |   | Undeveloped |   |   | Proved |   |
| Oil (Bbls)                         |   |             | 34,000  |   |         |   | -      |        |   |   | 1,000 |   |   |   | 35,000 |   |
| Gas (Mcf)                          |   |             | 156,000 |   |         |   | -      |        |   |   | 2,000 |   |   |   | 158,000 |   |
| Total (BOE)                        |   |             | 60,000  |   |         |   | -      |        |   |   | 1,000 |   |   |   | 61,000 |   |
|                               |   |             |    |   |         |   |   |        |   |   |   |   |   |   |   |   |
| Standardized measure of discounted |   |             |    |   |         |   |   |        |   |   |   |   |   |   |   |   |
| future net cash flows              |   |             |    |   |         |   |   |        |   |   |   |   |   | $ | 608,000 |   |

|             |   | Proved Reserves |   |   |   |   |
|------------------|--------|-----------------|--------|--------|--------|--------|
|             |   |            |   |   |   |   |   | Total Oil |   |   | Percent of |   |
|             |   | Oil             |   |   | Gas    |   |   | Equivalent |   |   | Total Oil |   |
|             |   | (Bbls)          |   |   | (Mcf)  |   |   | (BOE) |   |   | Equivalent |   |
| Henshaw          |   |            | 4,000  |   |   |   | 71,000 |   |   |   | 16,000 |   |   |   | 26.2 | % |
| Grayburg Jackson |   |            | 5,000  |   |   |   | 11,000 |   |   |   | 7,000 |   |   |   | 11.5 | % |
| Other            |   |            | 26,000 |   |   |   | 76,000 |   |   |   | 38,000 |   |   |   | 62.3 | % |
| Total            |   |            | 35,000 |   |   |   | 158,000 |   |   |   | 61,000 |   |   |   | 100.0 | % |

----

Item 

Item 

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| Item 5. | Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities |
|---------|--------------------------------------------------------------------------------------------------------------|

|           |   | Total Number |   |   |          |   |
|----------------|--------|--------------|--------|--------|---------------|--------|
|           |   | of Units     |   |   | Average Price |   |
| Period         |   | Purchased    |   |   | Paid Per Unit |   |
| January 2009   |   |         | -      |   |          | $      | - |   |
| February 2009  |   |         | -      |   |          |   | - |   |
| March 2009     |   |         | 10.0   |   |          |   | 58.00 |   |
| April 2009     |   |         | -      |   |          |   | - |   |
| May 2009       |   |         | -      |   |          |   | - |   |
| June 2009      |   |         | 15.0   |   |          |   | 58.00 |   |
| July 2009      |   |         | -      |   |          |   | - |   |
| August 2009    |   |         | -      |   |          |   | - |   |
| September 2009 |   |         | 24.0   |   |          |   | 58.00 |   |
| October 2009   |   |         | -      |   |          |   | - |   |
| November 2009  |   |         | -      |   |          |   | - |   |
| December 2009  |   |         | 25.0   |   |          |   | 58.00 |   |
| TOTALS         |   |         | 74.0   |   |          | $      | 58.00 |   |

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Item 

|                           |   | Years ended December 31, |    |
|--------------------------------|--------|--------------------------|---------|
|                           |   | 2009                     |    |   | 2008 |   |   | 2007 |   |   | 2006 |   |   | 2005 |   |
| Revenues                       |   | $                        | 294,069 |   |   | $ | 848,172 |   |   | $ | 407,282 |   |   | $ | 633,164 |   |   | $ | 667,326 |   |
|                           |   |                     |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Net income                     |   |                     | 113,865 |   |   |   | 690,122 |   |   |   | 250,013 |   |   |   | 499,831 |   |   |   | 559,694 |   |
|                           |   |                     |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Partners' share of net income: |   |                     |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                           |   |                     |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| General partners               |   |                     | 15,801  |   |   |   | 72,473 |   |   |   | 27,807 |   |   |   | 52,083 |   |   |   | 57,293 |   |
|                           |   |                     |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Limited partners               |   |                     | 98,064  |   |   |   | 617,649 |   |   |   | 222,206 |   |   |   | 447,748 |   |   |   | 502,401 |   |
|                           |   |                     |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Limited partners’ net    |   |                     |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| income per unit                |   |                     | 10.02   |   |   |   | 63.14 |   |   |   | 22.72 |   |   |   | 45.77 |   |   |   | 51.36 |   |
|                           |   |                     |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Limited partners' cash         |   |                     |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| distributions per unit         |   |                     | 21.12   |   |   |   | 64.45 |   |   |   | 30.94 |   |   |   | 50.29 |   |   |   | 55.20 |   |
|                           |   |                     |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Total assets                   |   | $                        | 505,438 |   |   | $ | 539,311 |   |   | $ | 521,052 |   |   | $ | 615,472 |   |   | $ | 506,858 |   |

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|                                      |   | Year Ended December 31, |    |
|-------------------------------------------|--------|-------------------------|---------|
|                                      |   | 2009                    |    |   | 2008 |   |   | 2007 |   |
| Oil production in barrels                 |   |                    | 8,517   |   |   |   | 10,424 |   |   |   | 9,756 |   |
| Gas production in mcf                     |   |                    | 31,589  |   |   |   | 31,032 |   |   |   | 30,595 |   |
| Total (BOE)                               |   |                    | 13,782  |   |   |   | 15,596 |   |   |   | 14,855 |   |
| Average price per barrel of oil           |   | $                       | 56.19   |   |   | $ | 99.88 |   |   | $ | 68.20 |   |
| Average price per mcf of gas              |   | $                       | 4.32    |   |   | $ | 9.02 |   |   | $ | 7.11 |   |
| Partnership distributions                 |   | $                       | 229,864 |   |   | $ | 700,648 |   |   | $ | 336,684 |   |
| Limited partner distributions             |   | $                       | 206,581 |   |   | $ | 630,462 |   |   | $ | 302,676 |   |
| Per unit distribution to limited partners |   | $                       | 21.12   |   |   | $ | 64.45 |   |   | $ | 30.94 |   |
| Number of limited partner units           |   |                    | 9,782   |   |   |   | 9,782 |   |   |   | 9,782 |   |

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|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |   | Page   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------|--------|
| Report of Independent Registered Public Accounting Firm                                                                                                    |   | 17     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |   |   |
| Balance Sheets                                                                                                                                             |   | 18     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |   |   |
| Statements of Operations                                                                                                                                   |   | 19     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |   |   |
| Statements of Changes in Partners' (Deficit) Equity                                                                                                        |   | 20     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |   |   |
| Statements of Cash Flows                                                                                                                                   |   | 21     |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |   |   |
| Notes to Financial Statements                                                                                                                              |   | 22     |

----

REPORT 

----

Southwest 

|                                       |   | December 31, |      |
|--------------------------------------------|--------|--------------|-----------|
|                                       |   | 2009         |      |   | 2008 |   |
| Assets                                     |   |         |      |   |   |   |
|                                       |   |         |      |   |   |   |
| Current assets:                            |   |         |      |   |   |   |
| Cash and cash equivalents                  |   | $            | 48,021    |   |   | $ | 45,290 |   |
| Receivable from Managing General Partner   |   |         | 57,756    |   |   |   | 37,449 |   |
| New Mexico income tax deposits             |   |         | 12,288    |   |   |   | 25,554 |   |
| Total current assets                       |   |         | 118,065   |   |   |   | 108,293 |   |
|                                       |   |         |      |   |   |   |   |   |
| Oil and gas properties - using the full-   |   |         |      |   |   |   |   |   |
| cost method of accounting                  |   |         | 3,189,866 |   |   |   | 3,189,361 |   |
| Less accumulated depreciation,             |   |         |      |   |   |   |   |   |
| depletion and amortization                 |   |         | 2,802,493 |   |   |   | 2,758,343 |   |
| Net oil and gas properties                 |   |         | 387,373   |   |   |   | 431,018 |   |
|                                       |   |         |      |   |   |   |   |   |
|                                       |   | $            | 505,438   |   |   | $ | 539,311 |   |
| Liabilities and Partners' (Deficit) Equity |   |         |      |   |   |   |   |   |
|                                       |   |         |      |   |   |   |   |   |
| Asset retirement obligation                |   | $            | 506,510   |   |   | $ | 424,384 |   |
|                                       |   |         |      |   |   |   |   |   |
| Partners' (deficit) equity:                |   |         |      |   |   |   |   |   |
| General partners                           |   |         | (83,385   | ) |   |   | (75,903 | ) |
| Limited partners                           |   |         | 82,313    |   |   |   | 190,830 |   |
|                                       |   |         |      |   |   |   |   |   |
| Total partners' (deficit) equity           |   |         | (1,072    | ) |   |   | 114,927 |   |
|                                       |   |         |      |   |   |   |   |   |
|                                       |   | $            | 505,438   |   |   | $ | 539,311 |   |

----

Southwest 

|                                     |   | Years ended December 31, |    |
|------------------------------------------|--------|--------------------------|---------|
|                                     |   | 2009                     |    |   | 2008 |   |   | 2007 |   |
| Revenues                                 |   |                     |    |   |   |   |   |   |   |
|                                     |   |                     |    |   |   |   |   |   |   |
| Income from net profits interests        |   | $                        | 293,983 |   |   | $ | 847,626 |   |   | $ | 405,439 |   |
| Interest income                          |   |                     | 86      |   |   |   | 546 |   |   |   | 1,745 |   |
| Other                                    |   |                     | -       |   |   |   | - |   |   |   | 98 |   |
|                                     |   |                     | 294,069 |   |   |   | 848,172 |   |   |   | 407,282 |   |
|                                     |   |                     |    |   |   |   |   |   |   |   |   |   |
| Expenses                                 |   |                     |    |   |   |   |   |   |   |   |   |   |
|                                     |   |                     |    |   |   |   |   |   |   |   |   |   |
| Depreciation, depletion and amortization |   |                     | 44,150  |   |   |   | 34,608 |   |   |   | 28,056 |   |
| Accretion expense                        |   |                     | 40,859  |   |   |   | 28,909 |   |   |   | 35,785 |   |
| General and administrative               |   |                     | 95,195  |   |   |   | 94,533 |   |   |   | 93,428 |   |
|                                     |   |                     | 180,204 |   |   |   | 158,050 |   |   |   | 157,269 |   |
|                                     |   |                     |    |   |   |   |   |   |   |   |   |   |
| Net income                               |   | $                        | 113,865 |   |   | $ | 690,122 |   |   | $ | 250,013 |   |
|                                     |   |                     |    |   |   |   |   |   |   |   |   |   |
| Net income allocated to:                 |   |                     |    |   |   |   |   |   |   |   |   |   |
| Managing General Partner                 |   | $                        | 14,221  |   |   | $ | 65,226 |   |   | $ | 25,026 |   |
|                                     |   |                     |    |   |   |   |   |   |   |   |   |   |
| General Partner                          |   | $                        | 1,580   |   |   | $ | 7,247 |   |   | $ | 2,781 |   |
|                                     |   |                     |    |   |   |   |   |   |   |   |   |   |
| Limited partners                         |   | $                        | 98,064  |   |   | $ | 617,649 |   |   | $ | 222,206 |   |
|                                     |   |                     |    |   |   |   |   |   |   |   |   |   |
| Per limited partner unit                 |   | $                        | 10.02   |   |   | $ | 63.14 |   |   | $ | 22.72 |   |

----

Southwest 

|                         |   | General  |    |   | Limited  |   |     |   |   |
|------------------------------|--------|----------|---------|--------|----------|--------|----------|--------|--------|
|                         |   | Partners |    |   | Partners |   |     | Total  |   |
| Balance at December 31, 2006 |   | $        | (71,989 | )      |     | $      | 284,113  |   |   | $ | 212,124 |   |
|                         |   |     |    |   |     |   |     |   |   |   |   |   |
| Net income                   |   |     | 27,807  |   |     |   | 222,206  |   |   |   | 250,013 |   |
|                         |   |     |    |   |     |   |     |   |   |   |   |   |
| Distributions                |   |     | (34,008 | )      |     |   | (302,676 | )      |   |   | (336,684 | ) |
|                         |   |     |    |   |     |   |     |   |   |   |   |   |
| Balance at December 31, 2007 |   |     | (78,190 | )      |     |   | 203,643  |   |   |   | 125,453 |   |
|                         |   |     |    |   |     |   |     |   |   |   |   |   |
| Net income                   |   |     | 72,473  |   |     |   | 617,649  |   |   |   | 690,122 |   |
|                         |   |     |    |   |     |   |     |   |   |   |   |   |
| Distributions                |   |     | (70,186 | )      |     |   | (630,462 | )      |   |   | (700,648 | ) |
|                         |   |     |    |   |     |   |     |   |   |   |   |   |
| Balance at December 31, 2008 |   |     | (75,903 | )      |     |   | 190,830  |   |   |   | 114,927 |   |
|                         |   |     |    |   |     |   |     |   |   |   |   |   |
| Net income                   |   |     | 15,801  |   |     |   | 98,064   |   |   |   | 113,865 |   |
|                         |   |     |    |   |     |   |     |   |   |   |   |   |
| Distributions                |   |     | (23,283 | )      |     |   | (206,581 | )      |   |   | (229,864 | ) |
|                         |   |     |    |   |     |   |     |   |   |   |   |   |
| Balance at December 31, 2009 |   | $        | (83,385 | )      |     | $      | 82,313   |   |   | $ | (1,072 | ) |

----

Southwest 

|                                                 |   | Years ended December 31, |     |
|------------------------------------------------------|--------|--------------------------|----------|
|                                                 |   | 2009                     |     |   | 2008 |   |   | 2007 |   |
| Cash flows from operating activities:                |   |                     |     |   |   |   |   |   |   |
| Cash received from net profits interests             |   | $                        | 286,942  |   |   | $ | 795,051 |   |   | $ | 434,331 |   |
| Cash paid for administrative fees and general        |   |                     |     |   |   |   |   |   |   |   |   |   |
| and administrative overhead                          |   |                     | (95,195  | ) |   |   | (100,593 | ) |   |   | (87,368 | ) |
| Interest received                                    |   |                     | 86       |   |   |   | 546 |   |   |   | 1,745 |   |
| Other                                                |   |                     | -        |   |   |   | - |   |   |   | 98 |   |
|                                                 |   |                     |     |   |   |   |   |   |   |   |   |   |
| Net cash provided by operating activities            |   |                     | 191,833  |   |   |   | 695,004 |   |   |   | 348,806 |   |
|                                                 |   |                     |     |   |   |   |   |   |   |   |   |   |
| Cash flows provided by investing activities:         |   |                     |     |   |   |   |   |   |   |   |   |   |
| Proceeds of oil and gas properties                   |   |                     | 40,762   |   |   |   | - |   |   |   | - |   |
|                                                 |   |                     |     |   |   |   |   |   |   |   |   |   |
| Cash flows used in financing activities:             |   |                     |     |   |   |   |   |   |   |   |   |   |
| Distributions to partners                            |   |                     | (229,864 | ) |   |   | (700,648 | ) |   |   | (336,684 | ) |
|                                                 |   |                     |     |   |   |   |   |   |   |   |   |   |
| Net increase (decrease) in cash and cash equivalents |   |                     | 2,731    |   |   |   | (5,644 | ) |   |   | 12,122 |   |
|                                                 |   |                     |     |   |   |   |   |   |   |   |   |   |
| Beginning of year                                    |   |                     | 45,290   |   |   |   | 50,934 |   |   |   | 38,812 |   |
|                                                 |   |                     |     |   |   |   |   |   |   |   |   |   |
| End of year                                          |   | $                        | 48,021   |   |   | $ | 45,290 |   |   | $ | 50,934 |   |
|                                                 |   |                     |     |   |   |   |   |   |   |   |   |   |
| Reconciliation of net income to net cash             |   |                     |     |   |   |   |   |   |   |   |   |   |
| provided by operating activities:                    |   |                     |     |   |   |   |   |   |   |   |   |   |
|                                                 |   |                     |     |   |   |   |   |   |   |   |   |   |
| Net income                                           |   | $                        | 113,865  |   |   | $ | 690,122 |   |   | $ | 250,013 |   |
|                                                 |   |                     |     |   |   |   |   |   |   |   |   |   |
| Adjustments to reconcile net income to net           |   |                     |     |   |   |   |   |   |   |   |   |   |
| cash provided by operating activities:               |   |                     |     |   |   |   |   |   |   |   |   |   |
| Depreciation, depletion and amortization             |   |                     | 44,150   |   |   |   | 34,608 |   |   |   | 28,056 |   |
| Accretion expense                                    |   |                     | 40,859   |   |   |   | 28,909 |   |   |   | 35,785 |   |
| Settlement of asset retirement obligations           |   |                     |     |   |   |   |   |   |   |   |   |   |
| for plugged and abandoned wells                      |   |                     | -        |   |   |   | (4,790 | ) |   |   | (49,346 | ) |
| (Increase) decrease in receivables and deposits      |   |                     | (7,041   | ) |   |   | (47,785 | ) |   |   | 78,238 |   |
| (Decrease) increase in accounts payable              |   |                     | -        |   |   |   | (6,060 | ) |   |   | 6,060 |   |
|                                                 |   |                     |     |   |   |   |   |   |   |   |   |   |
| Net cash provided by operating activities            |   | $                        | 191,833  |   |   | $ | 695,004 |   |   | $ | 348,806 |   |
|                                                 |   |                     |     |   |   |   |   |   |   |   |   |   |
| Noncash investing and financing activities:          |   |                     |     |   |   |   |   |   |   |   |   |   |
| Increase (decrease) in oil and gas properties -      |   |                     |     |   |   |   |   |   |   |   |   |   |
| Asset retirement obligations                         |   | $                        | 41,267   |   |   | $ | 10,726 |   |   | $ | (248 | ) |

----

Southwest 

| 1. | Organization |
|----|--------------|

|                                                               | Limited  |   | General  |
|--------------------------------------------------------------------|----------|--------|----------|
|                                                               | Partners |   | Partners |
| Oil and gas sales                                                  | 90%      |   | 10%      |
| Interest income on capital contributions                           | 100%     |   | -        |
| All other revenues                                                 | 90%      |   | 10%      |
| Organization and offering costs (1)                                | 100%     |   | -        |
| Syndication costs                                                  | 100%     |   | -        |
| Amortization of organization costs                                 | 100%     |   | -        |
| Property acquisition costs                                         | 100%     |   | -        |
| Gain/loss on property disposition                                  | 90%      |   | 10%      |
| Operating and administrative costs (2)                             | 90%      |   | 10%      |
| Depreciation, depletion and amortization of oil and gas properties | 100%     |   | -        |
| All other costs                                                    | 90%      |   | 10%      |

|   | (1) | All organization costs in excess of 3% of initial capital contributions will be paid by the Managing General Partner and will be treated as a capital contribution.  The Partnership paid the Managing General Partner an amount equal to 3% of initial capital contributions for such organization costs. |
|--------|-----|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | (2) | Administrative costs in any year, which exceed 2% of capital contributions shall be paid by the Managing General Partner and will be treated as a capital contribution. |
|--------|-----|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 2. | Summary of Significant Accounting Policies |
|----|--------------------------------------------|

----

| 2. | Summary of Significant Accounting Policies -continued |
|----|-------------------------------------------------------|

----

| 2. | Summary of Significant Accounting Policies - continued |
|----|--------------------------------------------------------|

----

|                                                        |   | 2009   |    |   | 2008   |   |
|-------------------------------------------------------------|--------|--------|---------|--------|--------|--------|
| Beginning of year                                           |   | $      | 424,384 |   |   | $      | 389,539 |   |
| Reduction of obligations due to wells plugged and abandoned |   |   | -       |   |   |   | (4,790 | ) |
| Reduction of obligations due to farm-outs                   |   |   | (468    | )      |   |   | (1,765 | ) |
| Accretion expense                                           |   |   | 40,859  |   |   |   | 28,909 |   |
| Revisions of previous estimates                             |   |   | 41,735  |   |   |   | 12,392 |   |
| Additional abandonment obligations from new wells           |   |   | -       |   |   |   | 99 |   |
| End of year                                                 |   | $      | 506,510 |   |   | $      | 424,384 |   |

| 4. | Commitments and Contingent Liabilities |
|----|----------------------------------------|

| 5. | Related Party Transactions |
|----|----------------------------|

----

| 5. | Related Party Transactions - continued |
|----|----------------------------------------|

| 6. | Oil and Gas Reserves Information (unaudited) |
|----|----------------------------------------------|

| ·   | amends the definition of proved reserves to require the use of average commodity prices based upon the prior 12-month period rather than year-end prices; |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | expands the type of technologies available to establish reserve estimates and categories; |
|--------------------|-------------------------------------------------------------------------------------------|

| ·   | modifies certain definitions used in estimating proved reserves; |
|--------------------|------------------------------------------------------------------|

| ·   | permits disclosure of probable and possible reserves; and |
|--------------------|-----------------------------------------------------------|

| ·   | permits disclosure of reserves based on different price and cost criteria, such as futures prices or management forecasts. |
|--------------------|----------------------------------------------------------------------------------------------------------------------------|

|                            |   | Oil (bbls) |    |   | Gas (mcf) |   |
|---------------------------------|--------|------------|---------|--------|-----------|--------|
| Total Proved -                  |   |       |    |   |      |   |
| January 1, 2007                 |   |       | 126,000 |   |      |   | 437,000 |   |
|                            |   |       |    |   |      |   |   |   |
| Revisions of previous estimates |   |       | (16,000 | )      |      |   | (126,000 | ) |
| Production                      |   |       | (10,000 | )      |      |   | (31,000 | ) |
| December 31, 2007               |   |       | 100,000 |   |      |   | 280,000 |   |
|                            |   |       |    |   |      |   |   |   |
| Revisions of previous estimates |   |       | (24,000 | )      |      |   | (6,000 | ) |
| Production                      |   |       | (10,000 | )      |      |   | (31,000 | ) |
| December 31, 2008               |   |       | 66,000  |   |      |   | 243,000 |   |
|                            |   |       |    |   |      |   |   |   |
| Revisions of previous estimates |   |       | (22,000 | )      |      |   | (53,000 | ) |
| Production                      |   |       | (9,000  | )      |      |   | (32,000 | ) |
| December 31, 2009               |   |       | 35,000  |   |      |   | 158,000 |   |
|                            |   |       |    |   |      |   |   |   |

----

| Proved developed reserves - |   |   |   |   |   |   |
|-----------------------------|--------|--------|--------|--------|--------|--------|
|                        |   |   |   |   |   |   |
| December 31, 2007           |   |   | 96,000 |   |   |   | 230,000 |   |
| December 31, 2008           |   |   | 65,000 |   |   |   | 195,000 |   |
| December 31, 2009           |   |   | 34,000 |   |   |   | 156,000 |   |

----

| 6. | Oil and Gas Reserves Information (unaudited) - continued |
|----|----------------------------------------------------------|

|                                          |   | 2009   |      |   | 2008   |   |      | 2007   |   |
|-----------------------------------------------|--------|--------|-----------|--------|--------|--------|-----------|--------|--------|
| Future cash inflows                           |   | $      | 2,493,000 |   |   | $      | 4,419,000 |   |   | $ | 11,256,000 |   |
| Production, development and abandonment costs |   |   | 1,591,000 |   |   |   | 2,451,000 |   |   |   | 4,208,000 |   |
| Future net cash flows                         |   |   | 902,000   |   |   |   | 1,968,000 |   |   |   | 7,048,000 |   |
| 10% annual discount for                       |   |   |      |   |   |   |      |   |   |   |   |   |
| estimated timing of cash flows                |   |   | 294,000   |   |   |   | 746,000   |   |   |   | 3,479,000 |   |
| Standardized measure of                       |   |   |      |   |   |   |      |   |   |   |   |   |
| discounted future net cash flows              |   | $      | 608,000   |   |   | $      | 1,222,000 |   |   | $ | 3,569,000 |   |

|                                                   |   | 2009   |      |   | 2008   |   |       | 2007   |   |
|--------------------------------------------------------|--------|--------|-----------|--------|--------|--------|------------|--------|--------|
| Sales of oil and gas produced, net of production costs |   | $      | (294,000  | )      |   | $      | (848,000   | )      |   | $ | (403,000 | ) |
| Changes in prices and production costs                 |   |   | (192,000  | )      |   |   | (2,269,000 | )      |   |   | 2,092,000 |   |
| Changes of production rates (timing) and others        |   |   | 55,000    |   |   |   | 699,000    |   |   |   | (154,000 | ) |
| Revisions of previous quantities estimates             |   |   | (305,000  | )      |   |   | (286,000   | )      |   |   | (900,000 | ) |
| Accretion of discount                                  |   |   | 122,000   |   |   |   | 357,000    |   |   |   | 267,000 |   |
| Discounted future net cash flows -                     |   |   |      |   |   |   |       |   |   |   |   |   |
| Beginning of year                                      |   |   | 1,222,000 |   |   |   | 3,569,000  |   |   |   | 2,667,000 |   |
| End of year                                            |   | $      | 608,000   |   |   | $      | 1,222,000  |   |   | $ | 3,569,000 |   |

| 7. | Selected Quarterly Financial Results – (unaudited) |
|----|----------------------------------------------------------|

|                                 |   | Quarter |   |
|--------------------------------------|--------|---------|--------|
|                                 |   | First   |   |   | Second |   |   | Third |   |   | Fourth |   |
| 2009:                                |   |    |   |   |   |   |   |   |   |   |   |   |
| Total revenues                       |   | $       | 62,757 |   |   | $ | 72,920 |   |   | $ | 68,201 |   |   | $ | 90,191 |   |
| Total expenses                       |   |    | 49,765 |   |   |   | 42,959 |   |   |   | 44,527 |   |   |   | 42,953 |   |
| Net income                           |   | $       | 12,992 |   |   | $ | 29,961 |   |   | $ | 23,674 |   |   | $ | 47,238 |   |
|                                 |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Net income per limited partners unit |   | $       | 1.08   |   |   | $ | 2.66 |   |   | $ | 2.09 |   |   | $ | 4.19 |   |

|                                 |   | Quarter |    |
|--------------------------------------|--------|---------|---------|
|                                 |   | First   |    |   | Second |   |   | Third |   |   | Fourth |   |
| 2008:                                |   |    |    |   |   |   |   |   |   |   |   |   |
| Total revenues                       |   | $       | 262,697 |   |   | $ | 315,394 |   |   | $ | 219,361 |   |   | $ | 50,720 |   |
| Total expenses                       |   |    | 38,800  |   |   |   | 41,800 |   |   |   | 39,364 |   |   |   | 38,086 |   |
| Net income                           |   | $       | 223,897 |   |   | $ | 273,594 |   |   | $ | 179,997 |   |   | $ | 12,634 |   |
|                                 |   |    |    |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Net income per limited partners unit |   | $       | 20.51   |   |   | $ | 25.09 |   |   | $ | 16.48 |   |   | $ | 1.06 |   |

----

Item 

Item 

----

Item 

----

Item 

Item 

----

Item 

Item 

Item 

| For the Year Ended December 31, |   | 2009   |   |   | 2008   |   |
|---------------------------------|--------|--------|--------|--------|--------|--------|
| Audit Fees                      |   | $      | 17,163 |   |   | $      | 18,030 |   |
| Audit Related Fees              |   |   | -      |   |   |   | - |   |
| Tax Fees                        |   |   | -      |   |   |   | - |   |
| All Other Fees                  |   |   | -      |   |   |   | - |   |
|                            |   |   |   |   |   |   |   |   |
| TOTAL                           |   | $      | 17,163 |   |   | $      | 18,030 |   |

----

Item 

| (a)    | (1)    | Financial Statements:                                                                                                                                                                                |
|--------|--------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|   |   |                                                                                                                                                                                                 |
|   |   | Included in Part II of this report                                                                                                                                                                   |
|   |   |                                                                                                                                                                                                 |
|   |   | Report of Independent Registered Public Accounting Firm                                                                                                                                              |
|   |   | Balance Sheets                                                                                                                                                                                       |
|   |   | Statements of Operations                                                                                                                                                                             |
|   |   | Statements of Changes in Partners' (Deficit) Equity                                                                                                                                                  |
|   |   | Statements of Cash Flows                                                                                                                                                                             |
|   |   | Notes to Financial Statements                                                                                                                                                                        |
|   |   |                                                                                                                                                                                                 |
|   | (2)    | Schedules required by Article 12 of Regulation S-X are either omitted because they are not applicable or because the required information is shown in the financial statements or the notes thereto. |
|   |   |                                                                                                                                                                                                 |
|   | (3)    | Exhibits:                                                                                                                                                                                            |

| 4      | (a)    | Certificate of Limited Partnership of Southwest Royalties Institutional Income Fund IX-B, L.P., dated March 9, 1989.  (Incorporated by reference from Partnership's Form 10-K for the fiscal year ended December 31, 1989.)   |
|--------|--------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|   |   |                                                                                                                                                                                                                                    |
|   | (b)    | Agreement of Limited Partnership of Southwest Royalties Institutional Income Fund IX-B, L.P. dated September 26, 1989.  (Incorporated by reference from Partnership's Form 10-K for the fiscal year ended December 31, 1989.) |
|   |   |                                                                                                                                                                                                                                    |
|   | 31.1   | Rule 13a-14(a)/15d-14(a) Certification                                                                                                                                                                                                  |
|   | 31.2   | Rule 13a-14(a)/15d-14(a) Certification                                                                                                                                                                                                  |
|   | 32.1   | Certification of Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C. Section 1350, as adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002                                                           |

----

Glossary 

----

----

Signatures

|   | Southwest Royalties Institutional Income Fund |
|--------|-----------------------------------------------|
|   | IX-B, L.P., a Delaware limited partnership    |
|   |                                          |
| By:    | Southwest Royalties, Inc., Managing           |
|   | General Partner                               |
|   |                                          |
|   |                                          |
| By:    | /s/ L. Paul Latham                            |
|   | L. Paul Latham                                |
|   | President and Chief Executive Officer         |
|   |                                          |
| Date:  | March 31, 2010                                |

|                                                                                  |   |                                                                                  |
|---------------------------------------------------------------------------------------|--------|---------------------------------------------------------------------------------------|
| /s/ Clayton W Williams                                                                |   | /s/ L. Paul Latham                                                                    |
| Clayton W. Williams, Chairman of the Board                                            |   | L. Paul Latham, President and a Director                                              |
| and a Director                                                                        |   |                                                                                  |
|                                                                                  |   |                                                                                  |
| Date:           March 31, 2010 |   | Date:           March 31, 2010 |
|                                                                                  |   |                                                                                  |
|                                                                                  |   |                                                                                  |
|                                                                                  |   |                                                                                  |
|                                                                                  |   |                                                                                  |
| /s/ Mel G. Riggs                                                                      |   |                                                                                  |
| Mel G. Riggs, Vice President – Finance,                                         |   |                                                                                  |
| Treasurer and a Director                                                              |   |                                                                                  |
|                                                                                  |   |                                                                                  |
| Date:           March 31, 2010 |   |                                                                                  |
|                                                                                  |   |                                                                                  |
|                                                                                  |   |                                                                                  |