Organization, Use of Estimates and Basis of Presentation (Tables)

9 Months Ended

Jan. 31, 2015

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	Three Months Ended						Nine Months Ended
	January 31,						January 31,
	2015			2014			2015			2014
Basic loss per share computation
Net loss attributable to common stockholders	$	(2,816,465	)	$	(574,207	)	$	(9,462,281	)	$	(5,133,684	)
Weighted Average common shares - basic		66,893,364			66,867,114			66,890,929			66,860,792
Basic net loss per share	$	(0.04	)	$	(0.01	)	$	(0.14	)	$	(0.08	)
Diluted loss per share computation
Net loss attributable to common stockholders	$	(2,816,465	)	$	(574,207	)	$	(9,462,281	)	$	(5,133,684	)
Less: Gain on derivative warrant liability		620,687			845,774			1,401,314			-
Loss available to common stockholders	$	(3,437,152	)	$	(1,419,981	)	$	(10,863,595	)	$	(5,133,684	)
Weighted Average common shares		66,893,364			66,867,114			66,890,929			66,860,792
Incremental shares from assumed exercise of warrants and stock options		352,213			-			352,213			-
Adjusted weighted average share - diluted		67,245,577			66,867,114			67,243,142			66,860,792
Diluted net loss per share	$	(0.05	)	$	(0.02	)	$	(0.16	)	$	(0.08	)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

The following table reflects the total potential share-based instruments outstanding at January 31, 2015 and 2014 that could have an effect on the future computation of dilution per common share:

	January 31,
	2015		2014
Stock options		23,990,008		22,633,955
Warrants		3,126,667		3,276,667
Total common stock equivalents		27,116,675		25,910,622