if (ns == null || ns.length() == 0) {
// check if schema attribute in allowed set
if (attrs.indexOf(name) < 0) {
ValidationContext vctx = (ValidationContext)ictx.getUserContext();
vctx.addError("Undefined attribute " + name, ictx.getStackTop());
}
} else if (SCHEMA_NAMESPACE.equals(ns)) {
// no attributes from schema namespace are defined