private static DocumentBuilder getParser() {
        try {
            // we'd really like to cache those DocumentBuilders, but we can't because:
            // 1. thread safety. parsers are not thread-safe, so at least
            //    we need one instance per a thread.
            // 2. parsers are non-reentrant, so now we are looking at having a
            // pool of parsers.
            // 3. then the class loading issue. The look-up procedure of
            //    DocumentBuilderFactory.newInstance() depends on context class loader
            //    and system properties, which may change during the execution of JVM.
            // so we really have to create a fresh DocumentBuilder every time we need one
            // - KK
            DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
            dbf.setNamespaceAware( true );
            dbf.setValidating( false );
            return dbf.newDocumentBuilder();
        } catch (ParserConfigurationException e) {
            // this should never happen with a well-behaving JAXP implementation. 
            throw new Error(e);