Stockholders’ equity: Preferred stock, $0.00001 par value; 5,000,000 shares authorized: none outstanding – – Common stock, $0.00001 par value: 600,000,000 shares authorized: 438,242,618 shares issued and 405,247,405 shares outstanding at August 31, 2013 and May 31, 2013 4,382 4,382 Additional paid-in capital 77,400,852 77,338,434 Accumulated deficit (55,288,139 ) (54,801,249 ) Common stock held in treasury, at cost – 32,995,213 shares at August 31, 2013 and May 31, 2013