2. STOCK-BASED COMPENSATION (Details Narrative) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 28, 2013	Feb. 29, 2012	Feb. 28, 2013	Feb. 29, 2012
Stock-based compensation costs capitalized as part of inventory	$ 25		$ 25
Stock-based compensation expense related to stock options	189	147	381	436
Unrecognized stock-based compensation cost	900		900
Estimated forfeitures of unvested stock based awards	3		3
Weighted average remaining period of the underlying options			2 years 11 months
Intrinsic value of options exercised	0	0	42	0
Weighted average remaining contractual life of the options exercisable and expected to be exercisable			3 years 11 months 20 days
Employee Stock Purchase Plan
Weighted average remaining period of the underlying options			7 months 6 days
Stock-based compensation related to the ESPP	12	35	46	83
Compensation cost related to options to purchase the Company's common stock under the ESPP but not yet recognized	$ 16		$ 16
ESPP shares issued			79,392	82,704