Exhibit 12.1

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

The following table sets forth our ratio of earnings to fixed charges for each of the periods indicated (in thousands):

	Year Ended December 31,
	2008			2007			2006			2005			2004
Earnings:
Net loss	$	(43,907	)	$	(24,339	)	$	(33,327	)	$	(18,128	)	$	(27,637	)
Fixed charges		1,636			3,456			4,496			5,502			5,661
Less: Interest capitalized		—			—			—			—			—
Total Earnings:	$	(42,271	)	$	(20,883	)	$	(28,831	)	$	(12,626	)	$	(21,976	)
Fixed Charges:
Interest expense		789			2,625			3,436			4,363			4,463
Portion of rent expense representative of interest		847			831			1,060			1,139			1,198
Total Fixed Charges	$	1,636		$	3,456		$	4,496		$	5,502		$	5,661
Ratio of Earnings to Fixed Charges(1)		—			—			—			—			—

(1) For purposes of computing the ratio of earnings to fixed charges, earnings consist of net loss plus fixed charges. Fixed charges consist of interest expense, amortization of debt expense and discount or premium related to indebtedness, whether expensed or capitalized, and that portion of rental payments under operating leases we believe to be representative of interest. Earnings were insufficient to cover fixed charges for these periods. The amount of the coverage deficiency was $43,907, $24,339, $33,327, $18,128 and $27,637 for the years ended December 31, 2008, 2007, 2006, 2005 and 2004, respectively.