MQ supports a singleton queue among different nodes.
You will have to refer to JBossMQ docs / wikis / forums. (I'm barelly an user of JBossMQ hence can't help much)
Whi is it stated in the docs that JBoss Messaging has better clustered performance, on the jboss.org homepage it states that 1.0.1 has clustering support, but there really is no support for it?!
I apologize for misreading this
"The JBoss Messaging team recently released version 1.0.1 GA as well as an alpha version that supports clustering"
But this is in the main documentation:
"Compared with JBossMQ, JBoss Messaging offers vastly improved performance in both single node and clustered environments. "