That still relies on a JarFile/ZipFile, which has native methods and is not serializable. I don't know why this has not been updated to a pure java implementation by now. The harmony impl is no different: http://svn.apache.org/viewvc/harmony/enhanced/classlib/trunk/modules/arch... There are java impls of zip/jar archives out there, I looked at a couple when starting the vfs work but they were not what I was looking for. Everything can be done off of the JarInputStream/ZipInputStream, but its not the most efficient. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4134590#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...