Overwrite default fallback content types
To correct this there is an option to define an other, non-rfc compliant fallback value. This can be done dynamicly per request with the PreProcessInterceptor infrastructure of RESTEasy. In the following example we will set "*/*; charset=UTF-8" as the new default fallback: import org.jboss.resteasy.plugins.providers.multipart.InputPart; @Provider @ServerInterceptor public class ContentTypeSetterPreProcessorInterceptor implements PreProcessInterceptor { public ServerResponse preProcess(HttpRequest request, ResourceMethod method) throws Failure, WebApplicationException { request.setAttribute(InputPart.DEFAULT_CONTENT_TYPE_PROPERTY, "*/*; charset=UTF-8"); return null; } }