Random Itunes Podcasting question

[Mr Bean]

I use Itunes for my pod casting needs because of all those handy "subscribe via Itunes" buttons and because Itunes has double the number of podcast I've listened to.

That said I use a Creative Zen Stone for my Podcasting, so I don't use Itunes except for the downloads, and it keeps stopping updating my postcasts because it believes I've not listen to any of them recently. I can force them to check of course but every week or so it stops updating them again because of that. Hunting through options screens finds no option to turn this off, is there any way to?