Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
May 31, 2012	May 31, 2011	May 31, 2010
Cash flows from operating activities:
Net loss	$ (3,389)	$ (3,373)	$ (481)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Stock-based compensation expense	709	947	1,733
Provision for doubtful accounts	16	15	59
Loss on disposal of asset	1	1	301
Gain on sale of long-term investment	(990)	0	0
Depreciation and amortization	491	573	690
Changes in operating assets and liabilities:
Accounts receivable	(1,285)	(501)	267
Inventories	(1,114)	(1,322)	837
Prepaid expenses and other	(42)	287	423
Accounts payable	570	(353)	(446)
Accrued expenses and deferred revenue	295	(280)	(138)
Income tax payable	(78)	(94)	28
Deferred lease commitment	(59)	(42)	(26)
Net cash (used in) provided by operating activities	(4,875)	(4,142)	3,247
Cash flows from investing activities:
Proceeds from sale of investments	1,375	0	0
Purchase of property and equipment	(45)	(15)	(69)
Net cash provided by (used in) investing activities	1,330	(15)	(69)
Cash flows from financing activities:
Line of credit borrowings, net	1,408	0	0
Proceeds from issuance of common stock and excercise of stock options	168	343	176
Net cash provided by financing activities	1,576	343	176
Effect of exchange rates on cash and cash equivalents	22	68	52
Net (decrease) increase in cash and cash equivalents	(1,947)	(3,746)	3,406
Cash and cash equivalents, beginning of year	4,020	7,766	4,360
Cash and cash equivalents, end of year	2,073	4,020	7,766
Supplemental cash flow information: Cash paid during the year for:
Income taxes	62	51	0
Interest	$ 4	$ 0	$ 0

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).