Sorry - I have no experience with that exception. At first, I was surprised that any stub errors would appear in a JMS context, but to be truthful I'm less than familiar with all the handshaking that JBoss does using JNDI. Although in the general case I'd starting looking at the network traffic (is it busy) and your initial marshaling of data, if applicable, I believe that in your situation something possibly JBoss-specific is going on. Some of the Jboss forums mention this sort of error happening when a non-clustered JBoss instance is contacting a clustered instance - so the first question is how have you setup your instances - are they clustered, which configuration are they using ("default", "all", your own config...) I'd suggest verifying your configuration, and post the relevant information. Maybe someone (...) will have an answer, or maybe I'll have time to look at the source and experiment [uh, don't hold your breath!] But whatever it is, it seems interesting! Stephen View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4074951#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...