Hi! I was trying to get Tomee 1.6.0 2013.10.05 (plain web profile without JAX-RS) to work with Jersey 2.3.1, but not success. The same project works flawlessly on Tomcat 7.0.42. The problem is a 500 error, which is not even logged in files by Tomee, but it just appears in the web page: java.lang.NullPointerException org.apache.openejb.util.classloader.URLClassLoaderFirst.shouldSkipJsf(URLClassLoaderFirst.java:359) org.apache.openejb.util.classloader.URLClassLoaderFirst.shouldDelegateToTheContainer(URLClassLoaderFirst.java:138) org.apache.tomee.catalina.LazyStopWebappClassLoader.loadClass(LazyStopWebappClassLoader.java:90) org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:491) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99) org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023) org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589) org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) java.lang.Thread.run(Thread.java:724) This is the sample project, which is nothing more than a plain Maven project with Jersey and Jackson, a web.xml file, an entity and a boundary (JAX-RS) class. The project is tested through NetBeans 7.4 RC1. https://github.com/zmirc/tomee-jersey-bug I know there is Tomee + Apache CXF, but Jersey is what I'm looking for. Thank you in advance. -- View this message in context: http://openejb.979440.n4.nabble.com/Tomee-1-6-0-2013-10-05-Jersey-2-3-X-openejb-class-loader-error-tp4665572.html Sent from the OpenEJB User mailing list archive at Nabble.com.