public GregorianDateTimeValue createInstance(XMLGregorianCalendar value) {
final DatatypeFactory factory = XsDatatypeFactory.getDatatypeFactory();
int month = value.getMonth();
int tz = value.getTimezone();
XMLGregorianCalendar cal = factory.newXMLGregorianCalendarDate(DatatypeConstants.FIELD_UNDEFINED, month, DatatypeConstants.FIELD_UNDEFINED, tz);
return new GregorianDateTimeValue(cal, GMONTH);
}