We have been getting this problem for a few weeks now. Every now and then our SBS 2008 box with Exchange 2007 seems to develop a problem and mail starts piling up in the Submission queue. No mail goes in or out and just sits in the queue and restarting Exchange services doesn't make a difference.
Currently the only fix seems to be a reboot but obviously this isn't a proper fix!
Firstly - does anyone have any suggestions on what could be causing this problem or any suggestions on anything I could try when this problem happens?
Secondly - does anyone know of something which can monitor the Exchange queues and alert us when the queues start backing up?