Quarterly report pursuant to sections 13 or 15(d)

Significant Accounting Policies (Details)

v2.4.0.8
Significant Accounting Policies (Details) (USD $)
3 Months Ended
Jul. 31, 2013
Apr. 30, 2013
Jul. 31, 2013
Stock Options [Member]
Jul. 31, 2012
Stock Options [Member]
Jul. 31, 2013
Warrant [Member]
Jul. 31, 2012
Warrant [Member]
Jul. 31, 2013
Convertible Debt [Member]
Jul. 31, 2012
Convertible Debt [Member]
Significant Accounting Policies [Abstract]                
Restricted cash $ 265,310 $ 265,173            
Letter of credit interest rate 0.20%              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]                
Antidilutive securities     9,110,592 2,070,000 9,090,292 882,500 1,357,143 951,126
Convertible debt             $ 800,000 $ 650,000