8. PRODUCT WARRANTIES (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 28, 2014	Feb. 28, 2013	Feb. 28, 2014	Feb. 28, 2013
Product Warranties Details
Balance at the beginning of the period	$ 208	$ 174	$ 222	$ 91
Accruals for warranties issued during the period	34	162	188	412
Settlement made during the period (in cash or in kind)	(46)	(139)	(214)	(306)
Balance at the end of the period	$ 196	$ 197	$ 196	$ 197