public void post(List<?> messages, AsyncCallback<Void> callback) {
   transport.post(messages, callback);
 }
 public void post(List<Serializable> messages, AsyncCallback<Void> callback) {
   transport.post(messages, callback);
 }
 public void post(Object message, AsyncCallback<Void> callback) {
   transport.post(message, callback);
 }
 public void post(Serializable message, AsyncCallback<Void> callback) {
   transport.post(message, callback);
 }