Marshalling JSON to JAXB annotated POJO causes "UnmarshalException: unexpected element (uri:"", local:"xxxxx")" in RESTEasy client on EAP

Issue

• We are experiencing a content marshalling issue with EAP 6 when marshalling JSON to JAXB annotated POJO.
• According to the RESTEasy documentation, "RESTEasy allows you to marshall JAXB annotated POJOs to and from JSON. This provider wraps the Jettison JSON library to accomplish this."
• But in my case, it is not working and I am receiving the following error:

org.jboss.resteasy.plugins.providers.jaxb.JAXBUnmarshalException: javax.xml.bind.UnmarshalException
 - with linked exception:
[javax.xml.bind.UnmarshalException: unexpected element (uri:"", local:"should_be_ignored"). Expected elements are <{}message>,<{}return>]

• Below is the actual class (note that we annotated @NoJackson to enable Jettison provider over Jackson explicitly):

@XmlRootElement(name="return")
@NoJackson
public class MyResponse {
    private List<Post> posts;

    @XmlElementWrapper(name = "messages")
    @XmlElement(name = "message")
    public List<Post> getPosts() { return posts; }

    public void setPosts(List<Post> posts) { this.posts = posts; }
}

• And the JSON string I am receiving after posting a message:

{
    "should_be_ignored": {},
    "messages": [
        { ... }
    ],
    ...
}

• Here is the RESTEasy client code running on EAP:

import org.jboss.resteasy.client.ClientRequest;
import org.jboss.resteasy.client.ClientResponse;

ClientRequest clientRequest = new ClientRequest("https://...");
ClientResponse<MyResponse> response = clientRequest.get(MyResponse.class);
MyResponse myResponse = response.getEntity();