Sometimes this happen when i’'m tryng to press reply in some threads. If i enter my credentials (though it still shows me as logged in upper right corner of page) nothing happens, it still shows me a login page. So i need to close that tab in Firefox and navigate to that thread again. Annoying.
Try to reply to this http://www.igniterealtime.org/forum/thread.jspa?threadID=25536
This is what email notify gave me. Though the real thread is with 25537 ID.
probably just an occasional bug