Exhibit 12.1

Calculation of Ratio of Earnings to Fixed Charges

	2001			2002			2003			2004			2005			Six-months ended 30-Jun-06
Earnings (loss)–
Loss before income taxes	$	(10,090	)	$	(34,017	)	$	(29,789	)	$	(93,271	)	$	(88,593	)	$	(43,130	)
Add fixed charges:
Interest expense on indebtedness	$	692		$	1,936		$	990		$	4,480		$	6,556		$	3,286
Estimated interest on rental expense		341			329			300			1,611			1947			973
Amortization of deferred closing costs related to convertible notes		—			294			156			521			816			408
Amortization of discount on convertible notes		—			511			271
Total Adjusted Loss	$	(9,057	)	$	(30,947	)	$	(28,072	)	$	(86,659	)	$	(79,274	)	$	(38,463	)
Fixed Charges–
Interest expense on indebtedness	$	692		$	1,936		$	990		$	4,480		$	6,556		$	3,286
Estimated interest on rental expense		341			329			300			1,611			1,947			973
Amortization of deferred closing costs related to convertible notes		—			294			156			521			816			408
Amortization of discount on convertible notes		—			511			271
Total Fixed Charges	$	1,033		$	3,070		$	1,717		$	6,612		$	9,319		$	4,667
Coverage deficiency	$	(10,090	)	$	(34,017	)	$	(29,789	)	$	(93,271	)	$	(88,593	)	$	(43,130	)