Hi, This is wierdest CNFE I have ever encountered. I am using JBoss Portal 2.6, JBoss AS 4.0.5 GA. I have a war file which contains acegi-security-1.0.1.jar in WEB-INF/lib This file has a class: org.acegisecurity.userdetails.UsernameNotFoundException. But still I get ClassNotFoundException: org.acegisecurity.userdetails.UsernameNotFoundException when portlet is initialized at server startup I have enabled logging of class loading in log4j. This is UsernameNotFoundException related logs from ucl.log: [82033,RepositoryClassLoader,main] loadClass org.jboss.mx.loading.UnifiedClassLoader3@12c5bfc{ url=file:/D:/jboss-cas-2.6/server/default/tmp/deploy/tmp61177pebble-mframe-exp.war/ ,addedOrder=54} name=org.acegisecurity.userdetails.UsernameNotFoundException, loadClassDepth=0 [82033,RepositoryClassLoader,main] loadClassImpl, name=org.acegisecurity.userdetails.UsernameNotFoundException, resolve=false [82033,LoadMgr3,main] Begin beginLoadTask, task=org.jboss.mx.loading.ClassLoadingTask@f1156e{classname: org.acegisecurity.userdetails.UsernameNotFoundException, requestingThread: Thread[main,5,jboss], requestingClassLoader: org.jboss.mx.loading.UnifiedClassLoader3@12c5bfc{ url=file:/D:/jboss-cas-2.6/server/default/tmp/deploy/tmp61177pebble-mframe-exp.war/ ,addedOrder=54}, loadedClass: nullnull, loadOrder: 2147483647, loadException: null, threadTaskCount: 0, state: 0, #CCE: 0} [82033,RepositoryClassLoader,main] getResourceLocally(org.jboss.mx.loading.UnifiedClassLoader3@27e353{ url=file:/D:/jboss-cas-2.6/server/default/conf/ ,addedOrder=1}), name=org/acegisecurity/userdetails/UsernameNotFoundException.class, resURL:null [82033,RepositoryClassLoader,main] getResourceLocally(org.jboss.mx.loading.UnifiedClassLoader3@16752c9{ url=file:/D:/jboss-cas-2.6/server/default/deploy/jboss-portal.sar/ ,addedOrder=9}), name=org/acegisecurity/userdetails/UsernameNotFoundException.class, resURL:null [82033,RepositoryClassLoader,main] getResourceLocally(org.jboss.mx.loading.UnifiedClassLoader3@18eb00c{ url=file:/D:/jboss-cas-2.6/server/default/deploy/jbossweb-tomcat55.sar/ ,addedOrder=10}), name=org/acegisecurity/userdetails/UsernameNotFoundException.class, resURL:null [82033,RepositoryClassLoader,main] getResourceLocally(org.jboss.mx.loading.UnifiedClassLoader3@b48230{ url=file:/D:/jboss-cas-2.6/server/default/deploy/jbossws14.sar/ ,addedOrder=11}), name=org/acegisecurity/userdetails/UsernameNotFoundException.class, resURL:null [82033,RepositoryClassLoader,main] loadClassLocally, org.jboss.mx.loading.UnifiedClassLoader3@12c5bfc{ url=file:/D:/jboss-cas-2.6/server/default/tmp/deploy/tmp61177pebble-mframe-exp.war/ ,addedOrder=54} name=org.acegisecurity.userdetails.UsernameNotFoundException [82049,RepositoryClassLoader,main] findClass, name=org.acegisecurity.userdetails.UsernameNotFoundException [82049,RepositoryClassLoader,main] CFNE: Adding to blacklist: org.acegisecurity.userdetails.UsernameNotFoundException [82049,RepositoryClassLoader,main] CFNE: Adding to blacklist: org.acegisecurity.userdetails.UsernameNotFoundException [82049,RepositoryClassLoader,main] loadClassLocally, org.jboss.mx.loading.UnifiedClassLoader3@12c5bfc{ url=file:/D:/jboss-cas-2.6/server/default/tmp/deploy/tmp61177pebble-mframe-exp.war/ ,addedOrder=54} name=org.acegisecurity.userdetails.UsernameNotFoundException not found [82049,LoadMgr3,main] Begin endLoadTask, task=org.jboss.mx.loading.ClassLoadingTask@f1156e{classname: org.acegisecurity.userdetails.UsernameNotFoundException, requestingThread: Thread[main,5,jboss], requestingClassLoader: org.jboss.mx.loading.UnifiedClassLoader3@12c5bfc{ url=file:/D:/jboss-cas-2.6/server/default/tmp/deploy/tmp61177pebble-mframe-exp.war/ ,addedOrder=54}, loadedClass: nullnull, loadOrder: 2147483647, loadException: null, threadTaskCount: 0, state: 0, #CCE: 0} [82049,RepositoryClassLoader,main] loadClass org.jboss.mx.loading.UnifiedClassLoader3@12c5bfc{ url=file:/D:/jboss-cas-2.6/server/default/tmp/deploy/tmp61177pebble-mframe-exp.war/ ,addedOrder=54} name=org.acegisecurity.userdetails.UsernameNotFoundException not found Any idea, whats going on? Thanks & Regards Advait Trivedi View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4054805#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...