2. STOCK-BASED COMPENSATION (Details Narrative) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 28, 2014	Feb. 28, 2013	Feb. 28, 2014	Feb. 28, 2013
Stock-based compensation costs capitalized as part of inventory		$ 25		$ 25
Stock-based compensation expense related to stock options	205	189	533	381
Intrinsic value of options exercised	162	0	315	42
Weighted average remaining contractual life of the options exercisable and expected to be exercisable			4 years 4 months 6 days
Employee Stock Purchase Plan
Weighted average remaining period of the underlying options			1 year 1 month 6 days
Stock-based compensation related to the ESPP	30	12	92	46
Compensation cost related to options to purchase the Company's common stock under the ESPP but not yet recognized	137		137
ESPP shares issued (in thousands)			75	79
ESPP shares available for issuance (in thousands)	400		400
1996 Stock Option Plan & 2006 Equity Incentive Plan
Unrecognized stock-based compensation cost related to unvested stock-based awards	1,013		1,013
Estimated forfeitures of unvested stock based awards	$ 3		$ 3
Weighted average remaining period of the underlying options			2 years 7 months 6 days