My Problem is solved but maybe still some bug in the messaging. My middle server (M) also has an internal Topic. I registered some durable subscribers and because I can not use JmsXA Connectionfactory I used XAConnectionFactory. JmsXA is not possible because then I can not use setClientId() (J2ee Spec). It seems that this is the root of this error. Means using XAConnectionFactory internally with heavy load and all the other configured and described stuff. My workarround: I changed my dynamic subscriber registration via a service to one single MDB which now handles all messages. Performance loss but now it uses JTA via JmsXA and everythink works fine... Greets Markus Lutum View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4082853#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...