CONDENSED CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Condensed Consolidated Statements Of Income
Service revenue	$ 18,013	$ 16,071	$ 35,034	$ 31,434
Product revenue	1,806	1,296	3,292	2,767
Total revenue	19,819	17,367	38,326	34,201
Operating expenses:
Cost of service revenue	4,059	3,589	7,874	6,971
Cost of product revenue	2,613	2,031	4,883	4,057
Research and development	1,540	1,271	2,947	2,497
Selling, general and administrative	10,742	8,525	20,151	17,883
Total operating expenses	18,954	15,416	35,855	31,408
Income from operations	865	1,951	2,471	2,793
Other income (expense), net	(11)	12	9	34
Income on change in fair value of warrant liability	0	9	0	167
Income before provision (benefit) for income taxes	854	1,972	2,480	2,994
Provision (benefit) for income taxes	22	3	(299)	7
Net income	$ 832	$ 1,969	$ 2,779	$ 2,987
Net income per share:
Basic	$ 0.01	$ 0.03	$ 0.04	$ 0.05
Diluted	$ 0.01	$ 0.03	$ 0.04	$ 0.05
Weighted average number of shares:
Basic	63,710	63,383	62,989	63,495
Diluted	67,759	64,847	66,833	64,807