channel.rollback();
MethodRegistry methodRegistry = session.getMethodRegistry();
AMQMethodBody responseBody = methodRegistry.createTxRollbackOkBody();
session.writeFrame(responseBody.generateFrame(channelId));
//Now resend all the unacknowledged messages back to the original subscribers.
//(Must be done after the TxnRollback-ok response).
// Why, are we not allowed to send messages back to client before the ok method?