EXHIBIT 12.1

	Ratio of Earnings to Fixed Charges
	(dollars in thousands, except ratio data)
	March 31,			December 31,			December 31,			December 31,			December 31,			December 31,
	2007 (1)			2006			2005			2004			2003			2002
Fixed Charges:
Interest expense on indebtedness (including amortization of debt expense and discount)	$	9,809		$	29,492		$	17,849		$	22,868		$	23,723		$	23,746
Interest expense on portion of rent expense representative of interest		5,117			19,899			14,614			9,089			7,604			7,206
Total Fixed Charges	$	14,926		$	49,391		$	32,463		$	31,957		$	31,327		$	30,952
Earnings (Loss):
Net loss before provision for income taxes	$	(51,029	)	$	(251,173	)	$	(239,439	)	$	(242,898	)	$	(185,324	)	$	(219,716	)
Fixed Charges per above		14,926			49,391			32,463			31,957			31,327			30,952
Total Earnings (Loss)		(36,103	)	$	(201,782	)	$	(206,976	)	$	(210,941	)	$	(153,997	)	$	(188,764	)
Ratio of Earnings to Fixed Charges		—			—			—			—			—			—
Coverage deficiency (2)(3)(4)	$	(51,029	)	$	(251,173	)	$	(239,439	)	$	(242,898	)	$	(185,324	)	$	(219,716	)

(1)	Amounts presented are for the three months ended March 31, 2007.
(2)	The Company’s Coverage deficiency for 2006 includes charges for lease termination and restructuring costs of $29,510 partially offset by a gain on the sale of an equity investment of $14,759.
(3)	The Company’s Coverage deficiency for 2004 includes net charges of $12,975, relating to a $15,408 charge for restructuring partially offset by a gain recognized on the extinguishment of debt of $2,433.
(4)	The Company’s Coverage deficiency for 2002 includes charges aggregating $46,396 arising from the Company’s impairment charge relating to its investment in CAT and a charge for construction design changes of $32,158 and $14,238, respectively.