7. STOCKHOLDERS EQUITY (Tables)

12 Months Ended

Apr. 30, 2014

Equity [Abstract]

Warrant Activity

	Warrants			Weighted Average Exercise Price
Outstanding at April 30, 2012		261,999		$	41.60
Issued		658,154			6.69
Cancelled		(67,568	)		44.40
Forfeited		(93,175	)		38.40
Outstanding at April 30, 2013		759,410		$	11.00
Issued		5,165,862			2.60
Exercised		(3,161,145	)		2.26
Forfeited		(1,661	)		126.00
Outstanding at April 30, 2014		2,762,466		$	4.28

Shares available for grant under the Plan

	Shares Available for Grant
Balances, at April 30, 2012		276,582
Options granted		(1,595	)
Options cancelled/forfeited		7,851
Restricted stock granted		(5,318	)
Restricted stock cancelled/forfeited		5,206
Balances, at April 30, 2013		282,726
additional shares reserved		3,600,000
Options granted		(3,637,822	)
Options cancelled/forfeited		1,300
Restricted stock granted		(135,662	)
Restricted stock cancelled/forfeited		44,866
Balances, at April 30, 2014		155,408

Options Activity

	Outstanding Options
	Number of Shares			Weighted Average Exercise Price		Aggregate Intrinsic Value
Balances, at April 30, 2012		17,592		$	81.20
Options granted		1,595		$	32.60
Options cancelled		(7,851	)	$	106.40
Balances, at April 30, 2013		11,336		$	57.00
Options granted		3,637,822		$	5.64
Options cancelled		(1,300	)	$	43.90
Balances, at April 30, 2014		3,647,858		$	5.79	$	8,736	(2)

Outstanding stock options

		Options Outstanding at April 30, 2014				Options Exercisable and Vested at April 30, 2014
Exercise Price		Number of Options		Weighted Average Remaining Contractual Life (Years)		Number of Options		Weighted Average Exercise Price
$	1.61 to $5.65		3,637,843		9.9		1,826,145	$	5.63
$	14.80 to $59.80		6,455		7.0		5,979	$	39.82
$	60.80 to $102.00		2,351		4.4		2,351	$	80.65
$	111.60 to $138.00		1,209		5.4		1,209	$	121.81
			3,647,858		9.9		1,835,684	$	5.91

Options vested and expected to vest

	Number of Option Shares		Weighted Average Exercise Price		Aggregate Intrinsic Value (1)		Weighted Average Remaining Contractual Life (Years)
Vested		1,835,684	$	5.91	$	8,736		9.9
Vested and expected to vest		3,645,025	$	5.79	$	9,237		9.9

Fair Value Assumptions

	For the year ended April 30
	2014			2013
Risk-free interest rate (weighted average)		1.80	%		1.29	%
Expected volatility (weighted average)		98.20	%		79.62	%
Expected term (in years)		6			7
Expected dividend yield		0.00	%		0.00	%

Restricted Stock Grants

	Outstanding Restricted Stock Grants
	Number of Shares			Weighted Average Grant Date Fair Value
Balances, at April 30, 2013		1,805		$	43.80
Restricted stock granted		5,318		$	35.00
Restricted stock vested		(4,465	)	$	32.60
Restricted stock cancelled		(741	)	$	36.20
Balances, at April 30, 2013		1,917		$	48.40
Restricted stock granted		135,662		$	3.00
Restricted stock vested		(50,235	)	$	2.30
Restricted stock cancelled		(31,503	)	$	1.67
Restricted stock forfeited		(13,363	)	$	4.49
Balances, at April 30, 2014		42,478		$	6.39