callbackClient.setSubsystem(JMSRemotingConnection.JMS_CALLBACK_SUBSYSTEM);
   public void setCallbackClient(Client client)   {      callbackClient = client;      //We explictly set the Marshaller since otherwise remoting tries to resolve the marshaller every time      //which is very slow - see org.jboss.remoting.transport.socket.ProcessInvocation      //This can make a massive difference on performance      //We also do this in JMSRemotingConnection.setupConnection      callbackClient.setMarshaller(new JMSWireFormat());      callbackClient.setUnMarshaller(new JMSWireFormat());   }