Using Restlet ClientResource cannot send entity to

I'm having problem with Restlet client call to a working rest service:

    final ClientResource resource = new ClientResource(Routes.PUBLIC_STORE_API);
    resource.setOnResponse(new Uniform() {
        public void handle(Request request, Response response) {
            try {
                Status status = response.getStatus();
                if(!Status.isError(status.getCode())){
                    String jsonResponse = response.getEntity().getText();
                } else {
                    // Handle error
                }
            } catch (Exception e){
                callback.failure(new Throwable(e.getMessage()));
            }
        }
    });
    JsniHelper.consoleLog("Adding object id=" + id + " type=" + type + " data=" + jsonObject);
    resource.getReference().addQueryParameter("type", type);
    resource.getReference().addQueryParameter("id",id);
    resource.post(jsonObject, MediaType.APPLICATION_JSON);

At the point of log above the object is a valid JSON string.

The Restlet ServerResource is able to get both the id and type Strings however the entity is always null:

@Post("json")
public Representation add(Representation entity){ // omitted }

I tried to use CURL and the Rest service was able to process the JSON string properly.

What could be the problem with my code in GWT?

Update: I have this in the POM

  <dependency>
      <groupId>org.restlet.gae</groupId>
      <artifactId>org.restlet.ext.gwt</artifactId>
      <version>2.2-RC3</version>
  </dependency>

In order to make this call run do the following things:

add the Json extension (org.restlet.ext.json.jar) of the framework taken from the GWT edition to your project
add the following dependency to your GWT module
then update your code as follow:

resource.post(new JsonRepresentation(MediaType.APPLICATION_JSON, jsonObject));

I notice that it works if you send a representation, instead of an object. The main problem is that when handling an object, the core module does not how to serialize it. In a JVM, we can plug a service that discovers the available converters that automagically convert a bean into a representation, we can't achieve this using GWT.

Having said that, I think you can integrate your client and server code in a easier way, by just using beans. The GWT client code can communicate using the specific GWT serialization format, any other client code using JSON.

Have a look at this code: http://restlet.com/technical-resources/restlet-framework/guide/2.3/introduction/first-steps/first-application