1. A method of evaluating grammars associated with a voice portal on a portal server, said method comprising: generating, for a current grammar of the voice portal representing a valid input for a first menu of the voice portal, a test input, the test input for the current grammar including a test pattern; providing the test input to the voice portal on the portal server using a voice server; receiving at least one measure of how distinguishable the current grammar is from other grammars of a set of active grammars that are active when the current grammar is active, the set of active grammars including the current grammar and at least one grammar from a second menu of the voice portal, the at least one measure based at least in part on analysis of the test pattern with respect to the set of active grammars, the at least one measure comprising at least one measure of how distinguishable the current grammar is from the at least one grammar from the second menu of the voice portal; and determining, based at least in part on the at least one measure, whether to modify the current grammar from the first menu to be distinguishable from the at least one grammar from the second menu.