Features that are in Weblogic that we should consider as well:

1. Two phase deployment. Like 2pc in transaction, if cluster-wide deployment
fails, we should rollback. We should be able to do this fairly easily in
farming service.

2. Idempotent operations in clustering failover, i.e., if we declare an
ejb method call is cluster-idempotent, then when it fail-over (can be
network error, etc.), our smart proxy should execute this operation again,
or we should  check to see whether we need to re-execute. Idempotent means
the operation can be execute multiple times without affect the state, e.g.,
setName().