grails - shouldFailWithCause fails test -

in grails 1.3.5 application have test method throws exception, test fails:

        shouldfailwithcause(myexception) {             vb.dostuff person         } 

the message is:
junit.framework.assertionfailederror: closure should have failed exception caused type myexception, instead found these exceptions: myexception: here comes message of exception.

it throws correct exception fails test. going wrong?

edit:

public void dostuff(person) {         if (!canpersondostuff(person)) {             throw new myexception("here comes message of exception")         } } 

shouldfailwithcause looks cause of exception instead of exception itself. can assertion work if add throw myexception cause of exception.

public void dostuff(person) {     if (!canpersondostuff(person)) {         throw new exception(new myexception("the message of exception"))         //or throw new exception(cause: new myexception("message"))     } } 

i rather use whatever logic have right in dostuff() assert shouldfail{..} instead of shouldfailwithcause{..} because former checks exact exception thrown.

shouldfail(myexception) {     vb.dostuff person }