mb.appendCallInit(MethodBuilder.FRAMEWORK_EXCEPTION_CLASS,
MethodBuilder.EXCEPTION_CONSTRUCTOR_SIGNATURE1);
mb.appendThrow();
// for valid extension mapping, just call the marshaller
mb.targetNext(ifvalid);
mb.loadObject();
mb.loadContext();
mb.appendCallInterface(MARSHALLERMARSHAL_METHOD,
MARSHALLERMARSHAL_SIGNATURE);
mb.appendReturn();