bstansberry(a)jboss.com Ok, could you comment next. I've written servlet with session supporting. I did stress test with 100 queries in sticky_mode = false. Aproximatelly 5% replications failed with concurrency problem in any synchronization modes and levels of isolation. Other test I did with sticky_mode = true. During work I broke connection between servers and often replication failed. I used version JBoss 4.0.5 GA. Thanks. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4044307#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...