There is no incompatibility and this is nothing to with your descriptors. You are asking a basic JMX question - this is nothing to do with JBoss Messaging. I suggest what you really need to do is buy a book on JMX - this will tell you how to invoke methods and query attributes on an MBean. There are plenty of books on Amazon that will tell you how to do this [hint] You cannot just call qmbean.getMessageCount() to get the message count from an MBean - it is *not* a normal Java object. [/hint] To invoke an operation on an MBean you do something like | server.invoke(new ObjectName("MyDomain:key=property"), "doSomething", new Object[0], new String[0]); | There are similar operations to query attributes and do various other things. This was explained in the wiki page that I told you about in the last post. As I say, this is not the forum for me to explain the basics of JMX to you. Please buy a JMX book or as in the JMX forum. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4048496#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...