I have the same problem, using Jboss 4.0.4.GA/Jboss IDE with default config. Apparently, this has nothing to do with AOP, but as u mentioned with cache features. Here is the error: -------------------------------------------------------------------------------- 00:57:48,078 INFO [JBossCacheManager] init(): replicationGranularity_ is 0 and invaldateSessionPolicy is 2 00:57:48,078 ERROR [JBossCacheManager] JBossCacheService to Tomcat clustering not found java.lang.NoClassDefFoundError: org/jboss/cache/CacheException at org.jboss.web.tomcat.tc5.session.JBossCacheManager.init(JBossCacheManager.java:144) at org.jboss.web.tomcat.tc5.TomcatDeployer.performDeployInternal(TomcatDeployer.java:332) at org.jboss.web.tomcat.tc5.TomcatDeployer.performDeploy(TomcatDeployer.java:103) at org.jboss.web.AbstractWebDeployer.start(AbstractWebDeployer.java:371) at org.jboss.web.WebModule.startModule(WebModule.java:83) at org.jboss.web.WebModule.startService(WebModule.java:61) at org.jboss.system.ServiceMBeanSupport.jbossInternalStart(ServiceMBeanSupport.java:289) at org.jboss.system.ServiceMBeanSupport.jbossInternalLifecycle(ServiceMBeanSupport.java:245) View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3967392#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...