* <p>
* To validate XML Schema correctly, we need to use the specialized VGM.
*/
static IVerifier createVerifier( Grammar g ) {
if( g instanceof XMLSchemaGrammar )
return new IDConstraintChecker(
(XMLSchemaGrammar)g,
new ErrorHandlerImpl() );
else
return new com.sun.msv.verifier.Verifier(
new REDocumentDeclaration(g),