I had the same problem with the web service provider style of web service. I am using jbossas 5 beta two with jbossws 1.2.1. It appears that jboss beta two uses xerces-2.7.1. After assembling all of the sources I found the ?real? cause of the NAMESPACE_ERR exception to be of mixing DOM 1 vs DOM 2 APIs. When a document is set for the SOAP body the dom tree for that document is copied into the soap body. If that document is made up of ElementImpl nodes rather than ElementNSImpl the call into Xerces fails with the now familiar NAMESPACE_ERR. To work around this issue change your code to use ?createElementNS?. I happen to be using Castor, which creates documents composed of ElementImpl nodes. I have a work around using the TransformerFactory of Xalan to create a new doc tree but would rather not have to copy the document twice. The details: SOAPBodyImpl SOAPBodyElement addDocument(Document doc) creates a soapFactory and begins the copy of elements from the document into the soapBody with the default as deep through soapFactory.createElement(rootElement). In SOAPFactoryImpl createElement(Element domElement, boolean deep) an assumption is made that the element passed in is an ElementNSImpl (has a localName). SOAPFactoryImpl ? | public SOAPElement createElement(Element domElement, boolean deep) throws SOAPException | { | if (domElement == null) | throw new IllegalArgumentException("Source node cannot be null"); | | if (domElement instanceof SOAPElement) | return (SOAPElement)domElement; | | String localName = domElement.getLocalName(); | String prefix = domElement.getPrefix() != null ? domElement.getPrefix() : ""; | String nsURI = domElement.getNamespaceURI() != null ? domElement.getNamespaceURI() : ""; | ? In the case of an ElementImpl the localName is null as well as the prefix, ElementImpl will have the field name set. Thus when DOMUtils createElement(String localPart, String prefix, String url) is called the localPart == null but the prefix is an empty string. DOMUtils public static Element createElement(String localPart, String prefix, String uri) | { | Document doc = getOwnerDocument(); | if (prefix == null || prefix.length() == 0) | { | log.trace("createElement {" + uri + "}" + localPart); | return doc.createElementNS(uri, localPart); | } | else | { | log.trace("createElement {" + uri + "}" + prefix + ":" + localPart); | return doc.createElementNS(uri, prefix + ":" + localPart); | } | } ? So the call into Xerces for createElementNS fails on setName(String namespaceURI, String qname) in ElementNSImpl as noted in the comment in the Xerces code: anonymous wrote : //NAMESPACE_ERR: | //1. if the qualified name is 'null' it is malformed. | //2. or if the qualifiedName is null and the namespaceURI is different from null, | // We dont need to check for namespaceURI != null, if qualified name is null throw DOMException. ElementNSImpl.java private void setName(String namespaceURI, String qname) { | | String prefix; | // DOM Level 3: namespace URI is never empty string. | this.namespaceURI = namespaceURI; | if (namespaceURI != null) { | //convert the empty string to 'null' | this.namespaceURI = (namespaceURI.length() == 0) ? null : namespaceURI; | } | | int colon1, colon2 ; | | //NAMESPACE_ERR: | //1. if the qualified name is 'null' it is malformed. | //2. or if the qualifiedName is null and the namespaceURI is different from null, | // We dont need to check for namespaceURI != null, if qualified name is null throw DOMException. | if(qname == null){ | String msg = | DOMMessageFormatter.formatMessage( | DOMMessageFormatter.DOM_DOMAIN, | "NAMESPACE_ERR", | null); | throw new DOMException(DOMException.NAMESPACE_ERR, msg); | } Test Code: The following snippet shows the exception. boolean createNS = false; | DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance(); | documentBuilderFactory.setNamespaceAware(true); | DocumentBuilder builder = documentBuilderFactory.newDocumentBuilder(); | document = builder.newDocument(); | | if(createNS){ | Element element = document.createElementNS(null, "Moo"); | document.appendChild(element); | } | else | { | // Causes the NAMESPACE_ERR to be thrown | Element element = document.createElement("Moo"); | element.appendChild(document.createTextNode(messageType)); | } | | | MessageFactory messageFactory = MessageFactory.newInstance(SOAPConstants.SOAP_1_1_PROTOCOL); | message = messageFactory.createMessage(); | | SOAPEnvelope envelope = message.getSOAPPart().getEnvelope(); | SOAPBody body = envelope.getBody(); | | body.addDocument(document); Documentation: http://xerces.apache.org/xerces-j/apiDocs/org/apache/xerces/dom/ElementNS... vs http://xerces.apache.org/xerces-j/apiDocs/org/apache/xerces/dom/ElementIm... View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4098072#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...