9. EQUITY COMPENSATION PLANS (Details) (USD $)	9 Months Ended
Jan. 31, 2013
Equity Compensation Plans Details
Number of Options Outstanding, Beginning	7,531,651
Number of Options Granted	8,556,862
Number of Options Exercised	(92,497)
Number of Options Cancelled or Expired	(508,315)
Number of Options Outstanding, Ending	15,487,701
Weighted Average Exercise Price Outstanding, Beginning	$ 2.90
Weighted Average Exercise Price Granted	$ 0.87
Weighted Average Exercise Price Exercised	$ 0.86
Weighted Average Exercise Price Canceled	$ 1.70
Weighted Average Exercise Price Outstanding, Ending	$ 1.83

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

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- Definition

Weighted average price of options that were either forfeited or expired.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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Number of share options (or share units) exercised during the current period.

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