Hello I'm not sur (my latest test are 2 month ago) but this pb occurs only when you start 2 different JVM (and try to synchronize them). I remember me that when you run test with 2 caches in the same JVM, all works fine. Maybe there is a JGroups optimisation for exchange in memory ? it's to be check, i'm actually busy on another job, but when i'll have more free time, i'll see this case. Christophe View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4054236#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...