The page the PM module is on can not have other modules added to it unless there are messages in the user in or out box.

Also, I added  the list module (very nice btw) to the page containing the pm module and unless there are messages in the user inbox or outbox the list module is not displayed.

I have the same problem, when there are no messages in the Inbox the url that is created points to a specific control and module on the page.

http://w3.ldam.ca/Home/tabid/1/ctl/NoMessages/mid/331/Default.aspx