// w3cDOM -> DTM -> DOMImpl
if (dom instanceof MultiDOM) {
final MultiDOM multiDOM = (MultiDOM) dom;
DTMDefaultBase dtm = (DTMDefaultBase)((DOMAdapter)multiDOM.getMain()).getDOMImpl();
DTMManager dtmManager = dtm.getManager();
DOM idom = (DOM)dtmManager.getDTM(new DOMSource(doc), false,
null, true, false);
// Create DOMAdapter and register with MultiDOM
DOMAdapter domAdapter = new DOMAdapter(idom,