after I add the serialVersionID, i get the old error and new error about log4j, I am using log4j 1.2.15 17:08:13,650 INFO [STDOUT] ERROR: java.lang.ClassCastException: CustomMessageBean | 17:08:13,652 INFO [WebappClassLoader] Illegal access: this web application instance has been stopped already. Could not load org.apache.log4j.spi.ThrowableInformation. The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. | java.lang.IllegalStateException | at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1244) | at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1204) | at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319) | at org.apache.log4j.spi.LoggingEvent.<init>(LoggingEvent.java:159) | at org.apache.log4j.Category.forcedLog(Category.java:391) | at org.apache.log4j.Category.error(Category.java:322) | at mail.AsyncQueueReceiver.onMessage(AsyncQueueReceiver.java:146) | at org.jboss.jms.client.container.ClientConsumer.callOnMessage(ClientConsumer.java:159) | at org.jboss.jms.client.container.ClientConsumer$ListenerRunner.run(ClientConsumer.java:976) | at org.jboss.messaging.util.JBMExecutor$TCLExecutor.run(JBMExecutor.java:99) | at EDU.oswego.cs.dl.util.concurrent.QueuedExecutor$RunLoop.run(QueuedExecutor.java:89) | at java.lang.Thread.run(Thread.java:595) | 17:08:13,658 ERROR [ClientConsumer] Failed to deliver message | java.lang.NoClassDefFoundError: org/apache/log4j/spi/ThrowableInformation | at org.apache.log4j.spi.LoggingEvent.<init>(LoggingEvent.java:159) | at org.apache.log4j.Category.forcedLog(Category.java:391) | at org.apache.log4j.Category.error(Category.java:322) | at mail.AsyncQueueReceiver.onMessage(AsyncQueueReceiver.java:146) | at org.jboss.jms.client.container.ClientConsumer.callOnMessage(ClientConsumer.java:159) | at org.jboss.jms.client.container.ClientConsumer$ListenerRunner.run(ClientConsumer.java:976) | at org.jboss.messaging.util.JBMExecutor$TCLExecutor.run(JBMExecutor.java:99) | at EDU.oswego.cs.dl.util.concurrent.QueuedExecutor$RunLoop.run(QueuedExecutor.java:89) | at java.lang.Thread.run(Thread.java:595) View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4206166#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...