我用websphere v9beta（支持JAX-RS 2.0）实现restful，下面这段代码

 java


 @GET
@Path("/getJson1")
@Produces(MediaType.APPLICATION_JSON)
public JSONObject getJSON1() {
    String input = "This is input";
    String output = "This is output";
    JSONObject outputJsonObj = new JSONObject();
    outputJsonObj.put("input", input);
    outputJsonObj.put("output", output);
    return outputJsonObj;
}

如果用import com.ibm.json.java.JSONObject实现JsonObject是运行正常的，但是如果用import org.json.JSONObject来实现就会报如下的错
[ERROR ] Problem with writing the data, class org.json.JSONObject, ContentType: application/json
[WARNING ] Interceptor for HelloResource1 has thrown exception, unwinding now
No serializer found for class org.json.JSONObject and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) )

按理说org.json跟通用啊？为什么websphere上运行会有这样的问题？