Hi Christian, this one already leads into the error. # schnipp public class DomNodeBaseXTest { public DomNodeBaseXTest() {} public Node myTestCase() throws ParserConfigurationException { DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance(); DocumentBuilder docBuilder = docFactory.newDocumentBuilder(); Document doc = docBuilder.newDocument(); Element rootElement = doc.createElement("root"); Element subElement = doc.createElement("leaf"); subElement.setTextContent("myText"); rootElement.appendChild(subElement); return rootElement; } } # schnapp Thanks a lot Andreas