I have an mdb configured with maxSessions = 20 and as I monitor the activity for the queue it is subscribed to often it will look to be processing 20 messages at a time but fairly often it will dip down to only a few or 0 for a 5-10 seconds before it looks like it retreives more messages from the queue. Any ideas on why I would be seeing these dips? I am primarily paying attention to InProcessMessageCount in the MBean inspector.