I'm still having a problem with BeyondPod. I created a thread on their forum too here: http://www.beyondpod.com/forum/showthread.php?3471-Podcast-not-sorting-by-date&p=13495
I think the issue has something to do with the date format but I'm not sure what date format BeyondPod is looking for yet. I've subscribed to this topic now, so I should respond faster than 1 year now.