The solution is:
XMLCh tempStr[100];
XMLString::transcode("LS", tempStr, 99);
DOMImplementation *impl = DOMImplementationRegistry::getDOMImplementation(tempStr);
DOMLSParser* parser = ((DOMImplementationLS*)impl)->createLSParser(DOMImplementationLS::MODE_SYNCHRONOUS, 0);
DOMConfiguration* conf = parser->getDomConfig ();
conf->setParameter(XMLUni::fgXercesSchema, true);
char *filename = "C:\\odx1.xml";
xercesc::DOMDocument *doc = 0;
try {
doc = parser->parseURI(filename);
DOMElement *element = doc->getElementById(XMLString::transcode("test"));
if(element != NULL) cout << "element found";
cout << "DONE";
}