Thanks. We are using the EAP version. Now I have tried the JBM 1.4.0SP3_CP7 - and replaced the jboss-messaging and jboss-messaging-client jars in the profile's lib directory (i.e. /server/messaging/lib ) Now what I'm seeing is that the second JBoss instance in the cluster is throwing out theses errors every few seconds: | 13:00:52,324 ERROR [GroupMember] Caught Exception in Receiver | java.lang.NullPointerException | at java.io.ByteArrayInputStream.<init>(ByteArrayInputStream.java:89) | at org.jboss.messaging.core.impl.postoffice.GroupMember.readRequest(GroupMember.java:354) | at org.jboss.messaging.core.impl.postoffice.GroupMember.access$1400(GroupMember.java:55) | at org.jboss.messaging.core.impl.postoffice.GroupMember$DataReceiver.receive(GroupMember.java:581) | at org.jgroups.JChannel.up(JChannel.java:1101) | at org.jgroups.stack.ProtocolStack.up(ProtocolStack.java:382) | at org.jgroups.stack.ProtocolStack.receiveUpEvent(ProtocolStack.java:398) | at org.jgroups.stack.Protocol.passUp(Protocol.java:520) | at org.jgroups.protocols.pbcast.GMS.up(GMS.java:768) | at org.jgroups.stack.UpHandler.run(Protocol.java:60) | 13:00:52,324 ERROR [UpHandler] UpHandler (GMS) caught exception | java.lang.IllegalStateException | at java.io.ByteArrayInputStream.<init>(ByteArrayInputStream.java:89) | at org.jboss.messaging.core.impl.postoffice.GroupMember.readRequest(GroupMember.java:354) | at org.jboss.messaging.core.impl.postoffice.GroupMember.access$1400(GroupMember.java:55) | at org.jboss.messaging.core.impl.postoffice.GroupMember$DataReceiver.receive(GroupMember.java:581) | at org.jgroups.JChannel.up(JChannel.java:1101) | at org.jgroups.stack.ProtocolStack.up(ProtocolStack.java:382) | at org.jgroups.stack.ProtocolStack.receiveUpEvent(ProtocolStack.java:398) | at org.jgroups.stack.Protocol.passUp(Protocol.java:520) | at org.jgroups.protocols.pbcast.GMS.up(GMS.java:768) | at org.jgroups.stack.UpHandler.run(Protocol.java:60) | | Any thoughts on this one? I'm going to try the CP05 patch to see if there's any difference.. Thanks. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4215714#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...