Hi genman, The system that I would like to create using jboss messaging is kind of messages router. So every messages should be delivered to specific user. In some occasions, I consider that users can decide to delete their account. In this case, operator needs to remove those messages somehow. Expiration Queue may become alternative solution. However, this may cause confusion between messages that should be keep in expired queue and messages that should be deleted. List Unique Property Value is useful also for that scenario. Operator needs a way to get available values in the queue to know whether there is any obsolete messages in the queue or not. List all Messages can be used but I think it can become a burden for the network if lots of messages were in queue. ==================================== For the implementation, I use something like remove all messages, but with filter. So every messages will be checked. If it matchs with the filter, it is going to be removed from the queue. Your idea seems simpler than mine. I will look into it. List Unique Property Value is implemented by using the same algorithm as ListAllMessages, but the method will only return the unique and requested values. This method may be used only for my case. So may be this method should be developed to give more functions, or may be there is another solution to get the value. Thank you for your comment. Best Regards, Hendra View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4078268#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...