code: public NodeList getElementsByTagNameNS(String namespaceURI,
                                           String localName)
    {
  
      error(XMLErrorResources.ER_FUNCTION_NOT_SUPPORTED);  //"getElementsByTagNameNS not supported!");
  
      return null;
    }
docs: Unimplemented. See org.w3c.dom.Element
  
  @param namespaceURI Namespace URI of the element
  @param localName Local part of qualified name of the element
  
  @return null