Hello, I have a problem starting up our application with the latest jboss-5.1.0.CR with enableLoadTimeWeaving=true where javassist throws the exception from the subject header during instrumentation of our classes. We don't experience this problem with jboss-5.0.1.GA. Inspecting the manifest of lib/javassist.jar for both jboss releases shows an identical version of 3.9.0.GA. Sorry if this is the wrong forum for this question Thanks, Mike View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4227649#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...