What could be the reason that the subscribed folders list becomes messed up?

If i do this:

$ rm ~/.maildir/.subscriptions $ evolution [subscribe to everything, exit program] $ cat ~/.maildir/.subscriptions debian sers va

$

(or some other random text which seems to come from parts of the folder list)

This makes Mozilla Mail go crazy. Evolution and Gnus work OK since they seem to have their own list, but switching back and forth between Evolution and Gnus makes Evolution forget the list.

I don't think I had this problem before. I used mbox then.