Warrants (Tables)

106 Months Ended

Jun. 30, 2012

Number of Warrants Outstanding

The number of warrants outstanding at June 30, 2012 and December 31, 2011 were as follows:

	June 30,		December 31,
	2012		2011
Liability-classified warrants		8,050,709		8,424,905
Equity-classified warrants		3,217,969		4,692,359
Total warrants		11,268,678		13,117,264

Assumptions Used In Binomial Valuation Model and Black-Scholes Valuation Model

The following assumptions were used in the Binomial/Monte Carlo valuation model at June 30, 2012 and the Black-Scholes valuation model at June 30, 2011:

	June 30, 2012			June 30, 2011
Risk-free interest rate		0.37	%		0.18 - 1.01	%
Expected life in years		2.44			0.92 - 3.43
Expected volatility		70	%		45 - 97	%
Expected dividend yield		0			0
Steps per year		12			N/A

Warrant Exercises

During the first six months of 2012, warrant exercises were as follows:

					Common		Liability
	Equity		Liability		Stock		Reclassed		Cash
(in thousands, except share data)	Warrants		Warrants		Issued		to Equity		Received
Cash exercises		102,744		-		102,744	$	-	$	210
Cashless exercises		12,329		373,617		89,859		412		-
		115,073		373,617		192,603	$	412	$	210

During the first six months of 2011, warrant exercises were as follows:

					Common		Liability
	Equity		Liability		Stock		Reclassed		Cash
(in thousands, except share data)	Warrants		Warrants		Issued		to Equity		Received
Cash exercises		2,259,770		-		2,259,770	$	-	$	12,293
Cashless exercises		39,832		144,905		59,308		265		-
		2,299,602		144,905		2,319,078	$	265	$	12,293