Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Cash flows from operating activities:
Net loss	$ (4,859)	$ (5,911)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	269	375
Share-based compensation	72	205
Loss on disposal of fixed assets		16
Change in fair value of warrants	(77)
Changes in operating assets and liabilities:
Accounts receivable, net	206	377
Product inventories	(1,635)	1,021
Prepaid expenses and other current assets	1	112
Trade accounts payable	114	(297)
Accrued salaries and benefits	(258)	528
Accrued warranty	10	8
Deferred revenues	392	(998)
Accrued liabilities	33	44
Net cash used in operating activities	(5,732)	(4,520)
Cash flows from investing activities:
Increase in restricted cash	(293)
Purchase of property, plant and equipment	(27)	(76)
Proceeds from disposition of assets		5
Net cash used in investing activities	(320)	(71)
Cash flows from financing activities:
Issuance of common shares for cash, net of issuance costs		5,734
Payment of notes payable		(119)
Repayment of long-term debt	(7)	(5)
Net cash (used in) provided by financing activities	(7)	5,610
Net (decrease) increase in cash and cash equivalents	(6,059)	1,019
Cash and cash equivalents, beginning of period	46,519	4,695
Cash and cash equivalents, end of period	40,460	5,714
Supplemental disclosures:
Cash paid for interest	1	1
Cash paid for income taxes	0	0
Non-cash transactions:
Acquisition of assets included in accounts payable		$ 85