2. STOCK-BASED COMPENSATION (Details 2) (USD $)	3 Months Ended
	Aug. 31, 2012	Aug. 31, 2011
Stock-Based Compensation Details 2
Available Shares, Beginning	839,000
Options granted	(439,000)
Options terminated	402,000
Plan shares expired	(180,000)
Available Shares, Ending	622,000
Options Outstanding, Beginning	2,957,000
Options Granted	439,000
Options terminated	(402,000)
Plan options exercised	(101,000)
Number of Options Outstanding, Ending	2,893,000
Weighted Average Exercise Price Outstanding, Beginning	$ 2.4
Weighted Average Exercise Price Granted	$ 1.28
Weighted Average Exercise Price Terminated	$ 4.48
Weighted Average Exercise Price Exercised	$ 0.67
Weighted Average Exercise Price Outstanding, Ending	$ 2.00
Aggregate Intrinsic Value, beginning balance	$ 587,000
Aggregate Intrinsic Value, ending balance	340,000
Options fully vested and expected to vest at August 31, 2012	2,836,000
Weighted Average Exercise Price for Options fully vested and expected to vest	$ 2
Aggregate Intrinsic Value for Options fully vested and expected to vest	333,000
Options exercisable at August 31, 2012	1,541,000	1,547,000
Options exercisable at August 31, 2012 Weighted Average Exercise Price	$ 2.70	$ 3.59
Options exercisable at August 31, 2012 Aggregate intrinsic value	$ 164,000