First, a JAR is just a re-named ZIP file, but is that ZIP actually the archived folder contaniing the JAR, a README file, a license, docs, etc? Or is it really just the classes ZIPped up?
Will JBoss know to accept a ZIP instead of a JAR? I've never used JBoss, but I remember that with WebLogic (at least 7.0) it did accept the classes12.zip that Oracle's driver used to come packaged as, so JBoss probably does.
Finally, did you try the
JBoss forum?