Credit Facility Agreement dated 21st March 2003 made between Slough Trading Estate Limited (the 'Lender') an English limited company, and Tipperary Corporation (the 'Borrower') a Texas, USA corporation.

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Exhibit 4.5

sloughestates
International

Slough Trading Estate Limited
000 Xxxx Xxxx
Xxxxxx XX0 0XX

Tel: x00 (0) 0000 000000
Fax: x00 (0) 0000 000000

xxx.xxxxxxxxxxxxx.xxx

Letter of Variation

Credit Facility Agreement dated 21^st March 2003 made between Slough Trading Estate Limited (the 'Lender') an English limited company, and Tipperary Corporation (the 'Borrower') a Texas, USA corporation.

We refer to the above facility which was used for 'Redeeming Promissory Notes issued to Slough Estates USA Inc. and for general corporate purposes' and confirm that the following terms be amended:

Amount:

The facility shall be increased from $US 8.5 Million to $US 11.5 Million on 25^th November 2003

All other terms and conditions remain unchanged.

Signed for and on behalf of		Signed for and on behalf of
Slough Trading Estate Limited		Tipperary Corporation
By:	/s/ R. D. KINGSTON	By:	/s/ XXXXX X. XXXXXXXX
Director		Director

sloughestates
International

Slough Trading Estate Limited
000 Xxxx Xxxx
Xxxxxx XX0 0XX

Tel: x00 (0) 0000 000000
Fax: x00 (0) 0000 000000

xxx.xxxxxxxxxxxxx.xxx

Second Letter of Variation

Credit Facility Agreement dated 21^st March 2003 and Letter of Variation dated 21^st November 2003 between Slough Trading Estate Limited (the 'Lender') an English limited company, and Tipperary Corporation (the 'Borrower') a Texas, USA corporation.

We refer to the above facility and Letter of Variation which was used for 'Redeeming Promissory Notes issued to Slough Estates USA Inc. and for general corporate purposes' and confirm that the following terms be amended:

Amount:

The facility shall be increased from $US 11.5 Million to $US 12 Million on 2^nd July 2004

All other terms and conditions remain unchanged.

Signed for and on behalf of		Signed for and on behalf of
Slough Trading Estate Limited		Tipperary Corporation
By:	/s/ R. D. KINGSTON	By:	/s/ XXXXX X. XXXXXXXX
Director		Director

sloughestates
International

Slough Trading Estate Limited
000 Xxxx Xxxx
Xxxxxx XX0 0XX

Tel: x00 (0) 0000 000000
Fax: x00 (0) 0000 000000

xxx.xxxxxxxxxxxxx.xxx

Third Letter of Variation

Credit Facility Agreement dated 21^st March 2003 and Letters of Variation dated 21 November 2003 and 1 July 2004 between Slough Trading Estate Limited (the 'Lender') an English limited company, and Tipperary Corporation (the 'Borrower') a Texas, USA corporation.

We refer to the above facility and Letters of Variation which were used for 'Redeeming Promissory Notes issued to Slough Estates USA Inc. and for general corporate purposes' and confirm that the following terms be amended:

Amount:

The facility shall be increased from $US 12 Million to $US 12.5 Million on 3^rd August 2004

All other terms and conditions remain unchanged.

Signed for and on behalf of		Signed for and on behalf of
Slough Trading Estate Limited		Tipperary Corporation
By:	/s/ R. D. KINGSTON	By:	/s/ XXXXX X. XXXXXXXX
Director		Director

sloughestates
International

Slough Trading Estate Limited
000 Xxxx Xxxx
Xxxxxx XX0 0XX

Tel: x00 (0) 0000 000000
Fax: x00 (0) 0000 000000

xxx.xxxxxxxxxxxxx.xxx

Fourth Letter of Variation

Credit Facility Agreement dated 21^st March 2003 and Letter of Variation dated 21 November 2003, 1 July 2004 and 3 August 2004 between Slough Trading Estate Limited (the 'Lender') an English limited company, and Tipperary Corporation (the 'Borrower') a Texas, USA corporation.

Amount:

The facility shall be increased from $US 12.5 Million to $US 13 Million on 3 September 2004

All other terms and conditions remain unchanged.

Signed for and on behalf of		Signed for and on behalf of
Slough Trading Estate Limited		Tipperary Corporation
By:	/s/ R. D. KINGSTON	By:	/s/ XXXXX X. XXXXXXXX
Director		Director