On windows, I can't seem to undeploy a file from JBoss by deleting it from the deploy directory while JBoss is running because JBoss seems to keep a file handle open to the archive. I've tried this with EAR and WAR files. I didn't have this problem on JBoss 4. If I'm not mistaken, this issue has existed on Beta1 and Beta2 as well.
Is this a bug? I couldn't find an existing issue..
It's a bug, related to some URLClassloader locking the file on Windows
http://jira.jboss.com/jira/browse/JBAS-4310