Thanks Mircea.Markus. Some more information: Websphere appends cellName, nodeName and server name (node1) to whever ClusterName I specify in the treecache.xml. During hot deployment, jboss cache jars try to find if there is any MBean with name TreeCache-Cluster. It does not find any and tries to create a new MBean with Name TreeCache-Cluster. In the process, websphere again appends the same information (cellName, nodeName ...etc) and it finds that there is bean with this name already exists and hence I get the exception. For the sake of experiment: I gave the name to ClusterName attribute as anonymous wrote : TreeCache-Cluster,cell=TD2471N | ode01Cell,node=TD2471Node01,process=server1, which Websphere was complaining. And it all started working OK. But this definitely not a solution because this information is machine specific. Let me know how to fix it. Thanks, View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4257482#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...