* @return command authenticator object instance or <code>null</code> if no authenticator is configured
*
* @throws Exception if failed to instantiate the configured class name
*/
public CommandAuthenticator getCommandAuthenticator() throws Exception {
CommandAuthenticator obj = null;
String value = m_preferences.get(ServiceContainerConfigurationConstants.COMMAND_AUTHENTICATOR, "");
if ((value != null) && (value.length() > 0)) {
obj = (CommandAuthenticator) Class.forName(value).newInstance();
}