* @return Created class or <code>null</code>.
     */
    private Class createClass(String className) {
            Class clazz;

            // use approprite ClassLoader
            try {
                    if (classLoader != null) {
                            clazz = classLoader.loadClass(className);
                    } else {
                            clazz = Class.forName(className);
                    }
            } catch (Throwable t) {
                if(debug)   t.printStackTrace();
                    return null;
            }

            return clazz;
    }