What feature is it?
If you need a temporary patch to get Jboss working on linux AMD64 without crashing on startup due to problems with opening zip files in the RepositoryClassLoader see:
JBAS-2483, jboss.system:type=Server (exit|halt) 10 doesn't restart jboss
We are using JBoss 3.2.5. We plan to base our application on JBoss 4 next release.