Securities Purchase Agreement (Tables)

6 Months Ended

Jun. 30, 2012

Securities Purchase Agreement [Abstract]

Fair values of derivative liabilities

	Fair Value Measurements at
	June 30, 2012		December 31, 2011
Embedded Derivatives of Series C-1 2 Preferred (including dividends paid in Series C-1 2 Preferred)	$	3,408	$	3,628
Embedded Derivatives of accrued dividends payable in Series C-1 2 Preferred		654		52
Series D-1 2 Warrants		588		2,539
Series C-2 2 Warrants for:
Series C-2 2 Preferred		3,535		3,785
Series D-2 2 Warrants		5,621		5,266
	$	13,806	$	15,270

Embedded Derivatives

	June 30, 2012			December 31, 2011
Closing price per share of common stock	$	0.06		$	0.27
Conversion price per share	$	0.05		$	0.60
Volatility		87.5	%		88.0	%
Risk-free interest rate		0.64	%		0.83	%
Credit spread		20.4	%		20.9	%
Remaining expected lives of underlying securities (years)		4.5			5.0

Series D1 warrants using binomial option pricing

	June 30, 2012			December 31, 2011
Closing price per share of common stock	$	0.06		$	0.27
Conversion price per share	$	0.05		$	0.60
Volatility		67.1	%		67.5	%
Risk-free interest rate		0.30	%		0.28	%
Remaining expected lives of underlying securities (years)		1.7			2.2
Probability of Strategic Transaction		N/A			70	%

Series C2 warrants using binomial option pricing

	June 30, 2012			December 31, 2011
Closing price per share of common stock	$	0.06		$	0.27
Conversion price per share	$	0.05		$	0.60
Volatility		87.5	%		88.0	%
Risk-free interest rate		0.64	%		0.83	%
Credit spread		20.4	%		20.9	%
Remaining expected lives of underlying securities (years)		4.5			5.0
Time to exercise (months)		18			24