Thanks for replying Alex. I can allocate more resources but my main concern is why my messages are left in the queue. What happens to them after that? When a thread cannot get hold of any database connection, is that when the message is left in the queue? But I would imagine the StartListener receives the message first and then starts processing BPEL so message is already read. so I want to find out in which cases, the messages are just left in the queue. btw, today I was trying to have more control over when listener picks up message so I tried JMS connection.stop(). According to API documentation it is supposed to stop the delivery of messages but that did not happen. I think this is not the right forum for that question but in case you know the answer, please let me know. Thank you, Meghana. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4152178#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...