Last time I tried, IBM had released their 1.4.0 version of the JDK, and it wouldn't run under the new threading stuff in RedHat 9 backported from the 2.5.X development kernel. But, apparently, IBM has released a 1.4.1 JDK now (couple of weeks ago) that actually fires up and run on RedHat 9.
I don't know how the IBM JVM stacks up against Sun JVM these day, but IBM has a reputation for making fast JVMs, so on top of the new threading implementation in RedHat 9 it could prove to be a nice platform for JBoss. I haven't tested it much, but it'd be nice to know if anyone else has experience with this combination to share.
