I just tried the WildFly snapshot containing RESTEasy 3.0.1.Final. After I added the Maven dependency org.jboss.resteasy:resteasy-cache-core (http://docs.jboss.org/resteasy/docs/3.0.1.Final/userguide/html/Cache_NoCache_CacheControl.html#server_cache) I got the following stacktrace:

15:29:01,083 ERROR [org.jboss.msc.service.fail] MSC000001: Failed to start service jboss.undertow.deployment.default-host./shop: org.jboss.msc.service.StartException in service jboss.undertow.deployment.default-host./shop: Failed to start service
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1898) [jboss-msc-1.2.0.Beta1.jar:1.2.0.Beta1]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [rt.jar:1.7.0_25]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [rt.jar:1.7.0_25]
at java.lang.Thread.run(Thread.java:724) [rt.jar:1.7.0_25]
Caused by: java.lang.NullPointerException
at org.jboss.resteasy.spi.metadata.ResourceConstructor.<init>(ResourceConstructor.java:24)
at org.jboss.resteasy.spi.metadata.ResourceBuilder$ResourceConstructorBuilder.<init>(ResourceBuilder.java:424)
at org.jboss.resteasy.spi.metadata.ResourceBuilder$ResourceClassBuilder.constructor(ResourceBuilder.java:96)
at org.jboss.resteasy.spi.metadata.ResourceBuilder.constructor(ResourceBuilder.java:681)
at org.jboss.resteasy.plugins.server.resourcefactory.POJOResourceFactory.registered(POJOResourceFactory.java:41)
at org.jboss.resteasy.core.ResourceMethodRegistry.addResourceFactory(ResourceMethodRegistry.java:207)
at org.jboss.resteasy.core.ResourceMethodRegistry.addResourceFactory(ResourceMethodRegistry.java:193)
at org.jboss.resteasy.core.ResourceMethodRegistry.addResourceFactory(ResourceMethodRegistry.java:179)
at org.jboss.resteasy.core.ResourceMethodRegistry.addResourceFactory(ResourceMethodRegistry.java:156)
at org.jboss.resteasy.core.ResourceMethodRegistry.addPerRequestResource(ResourceMethodRegistry.java:75)
at org.jboss.resteasy.spi.ResteasyDeployment.registration(ResteasyDeployment.java:400)
at org.jboss.resteasy.spi.ResteasyDeployment.start(ResteasyDeployment.java:241)
at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.init(ServletContainerDispatcher.java:112)
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.init(HttpServletDispatcher.java:36)
at io.undertow.servlet.core.ManagedServlet$DefaultInstanceStrategy.start(ManagedServlet.java:146)
at io.undertow.servlet.core.ManagedServlet.start(ManagedServlet.java:63)
at io.undertow.servlet.core.DeploymentManagerImpl.start(DeploymentManagerImpl.java:377)
at org.wildfly.extension.undertow.deployment.UndertowDeploymentService.startContext(UndertowDeploymentService.java:81)
at org.wildfly.extension.undertow.deployment.UndertowDeploymentService.start(UndertowDeploymentService.java:68)
at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1942) [jboss-msc-1.2.0.Beta1.jar:1.2.0.Beta1]
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1875) [jboss-msc-1.2.0.Beta1.jar:1.2.0.Beta1]
... 3 more