Ryan, Help is always welcome :) We are going to need to reproduce the error, so we can test our fix. Is it enough trying to intercept a simple example of hibernate? Or is there any aditional step we must follow to reproduce it? Second, in the mean time, wouldn't it be enough to use the "jboss.aop.exclude" system property? This property allows you to specify one or more class patterns (separated by commas, without wildcards). Every class that matches one of the exclude patterns won't be instrumented by JBoss AOP, thus avoiding the error. An example would be jboss.aop.exclude=$$_javassist If you are using JBoss AS, you can set the exclude property by editing jboss-aop-jdk50.deployer/META-INF/jboss-service.xml. If your app is standalone, just define this property as you do with any java system property. Let me know if this solves your problem until we fix the bug. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4109489#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...