We found the in order to run JBossCache 1.4 on JBoss 4.0.2, we had to
add jboss-serialization.jar to the server/myServer/lib directory.
paul
Yes, this has been documented on http://labs.jboss.com/portal/jbosscache/compatibility for JBoss AS 4.0.3.SP1. It will apply to 4.0.2 as well.