if (_engine == null) {
// turn on persistence if required
String persistOn = context.getInitParameter("EnablePersistance");
boolean persist = "true".equalsIgnoreCase(persistOn);
_engine = new EngineGatewayImpl(persist);
context.setAttribute("engine", _engine);
}
// turn on exception monitoring if required
String exServiceOn = context.getInitParameter("EnableExceptionService");
if (exServiceOn.equalsIgnoreCase("true")) {