These resteasy jars in EAP 6.4.0.DR7 don't have specification and implementation version in their manifest: resteasy-jsapi-2.3.8.Final-redhat-3.jar resteasy-multipart-provider-2.3.8.Final-redhat-3.jar resteasy-yaml-provider-2.3.8.Final-redhat-3.jar resteasy-jaxb-provider-2.3.8.Final-redhat-3.jar resteasy-spring-2.3.8.Final-redhat-3.jar resteasy-hibernatevalidator-provider-2.3.8.Final-redhat-3.jar resteasy-jaxrs-2.3.8.Final-redhat-3.jar resteasy-cdi-2.3.8.Final-redhat-3.jar resteasy-atom-provider-2.3.8.Final-redhat-3.jar resteasy-jackson-provider-2.3.8.Final-redhat-3.jar resteasy-jettison-provider-2.3.8.Final-redhat-3.jar For more information see BZ 900033