How are you forwrding messages in the MDB? Do you use the JMS ra or vanilla JMS.
Your problem I would guess is that the connection needs to be reestablishes each time when a send is tried. The JMS ra will probably not do that (wich could be worh looking at).
I am using JMS ra to forward the messages. Is this the wrong way to do it in general, or is it a limitation of JBossMQ?
It's a limitiation of JMS ra you could say. It does not have any failsafe semantics. It shoudl probably be added some more failsafe handling to it, but I do not have time to do that right now.
If you want failsafe you you will have to manage the JMS connection your self.