------------- | | L1 L2 | <-- linux cluster, 2 nodes, with clustered Queues, Q1 and Q2 | ------------- | ^ ^ | | | | W1 W2 | | L == linux JBossAS 4.2.2.GA with JBM 1.4.0.SP1 | W == Windows JBossAS 4.2.2.GA. Not clustered , running consumer service | | Identical services running on L1 and L2 each post request messages to a clustered queue (Q1). The thread that posted a message then calls MessageConsumer.receive() on a response queue (Q2). Both W1 and W2 are connected to L1 using ClusteredConnectionFactory. Therefore, all messages posted to L2 are sucked over to L1 and consumed by W1 and W2. W1 and W2 post response messages to response queue (Q2) on L1. The MessageConsumer.receive() called by the L1 service receives the response messages it is waiting for. The MessageConsumer.receive() called by the L2 service never returns. The response messages that L2 is waiting for are stuck on L1-Q2. Eventually, they are sucked over to L2-Q2 and L2 finally receives them. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4110977#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...