I really have searched, and have not heard this before. Would you mind elaborating for me? Are you saying that I can create a read/write disk image on my buffalo NAS and use that to back up with TM?
As best I understand it, and I'm the one having problems so maybe I'm not up to snuff, any drive that can be mounted can be a Time Machine backup disk. Officially, it's any external drive, or any drive on any Leopard machine on your network, and that's what I've got, but give it a shot, see if it works. Time Machine actually memorized how to get access to my network drive... Happy days if it works for you.