@XmlTransient not working for JAX-RS JSON responses in RESTEasy

Issue

• I am using JBoss EAP 6.3 straight out of the box. In other words, I have not tweaked or modified it except for adding datasources.
• I have a POJO class with some fields annotated with @XmlTransient. This annotation is being ignored.
• This problem happens only when a JAX-RS method is annotated with @Produces("application/json"); it does not happen for a method with @Produces("application/xml"), i.e. @XmlTransient just work as expected for XML responses.
• For instance, with the following POJO class:

    private String ignored;
    @XmlTransient
    public String getIgnored() { return ignored; }

• For "application/xml" I get:

<return>
  <message>
    <content>Goodbye, RESTEasy!</content>
  </message>
</return>

• But for "application/json" I get:

{
  "message" : {
    "content" : "Hello, RESTEasy!",
    "ignored" : "Ignore me!!!"
  }
}