Exhibit 12.1

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

Our earnings are inadequate to cover fixed charges. The following table sets forth the dollar amount of the coverage deficiency for each of the years ended December 31, 2011, 2010, 2009, 2008 and 2007. We have not included a ratio of earnings to combined fixed charges and preferred stock dividends because we do not have earnings. We have derived the deficiency of earnings to cover fixed charges from our historical financial statements. The following should be read in conjunction with our consolidated financial statements, including the notes thereto, and the other financial information included or incorporated by reference herein.

	Fiscal Year Ended December 31,
	2011			2010			2009			2008			2007
(dollars in thousands)
Net loss	$	(109,388	)	$	(140,166	)	$	(87,703	)	$	(43,754	)	$	(21,518	)
Add back: Fixed charges		518			367			146			183			241
Total adjusted net loss	$	(108,870	)	$	(139,799	)	$	(87,557	)	$	(43,571	)	$	(21,277	)
Fixed charges:
Interest expense		287			194			30			92			216
Interest portion of rental expense		231			173			116			91			25
Total fixed charges		518			367			146			183			241
Deficiency of earnings available to fixed charges(1)	$	(109,388	)	$	(140,166	)	$	(87,703	)	$	(43,754	)	$	(21,518	)

(1) Because of the deficiency of earnings available to cover fixed charges, the ratio information is not applicable.