seems like there is no JTS version that is compatible with JBossAS 4.2.x. I don't know if a clustered configuration works without JTS.
This is what happens with tow independent JBossAS instances using JTA:
I have Bean A on Host 1 call a method of Bean B on Host 2 within a Container Managed Transaction. After the call I roll back the transaction, but the rollback only happens on Host 1, on Host 2 a commit happens. If Bean A and Bean B are both deployed on Host 1 (same server JVM) the rollback works fine.