// reset msgType, might have been modified in below unsubscribe try
reqMessage.setMessageType(this.getKey());
// set up callback for normal client unsubscribe operation
callback = new CscUnsubscribeCommandCallback(request, response, responderCallback, cascSubscription);
try {
server.unsubscribe(reqMessage, callback, otiOnSCMillis - (i * Constants.WAIT_FOR_FREE_CONNECTION_INTERVAL_MILLIS));
// delete unreferenced nodes in queue
publishMessageQueue.removeNonreferencedNodes();
// no exception has been thrown - get out of wait loop
break;
} catch (ConnectionPoolBusyException ex) {