> I've seen this a couple of times over the past month or so... all of
> the sudden 20-50 previously marked as read spam messages are moved
> from the spam folder to my inbox automatically. Has anyone had this
> happen to them?
I haven't seen this.
But for the past month, I keep getting new spam going into my Inbox, a
dozen or so daily. They all look the same, they all are obvious spam
(you can tell from the sender, the subject, and the body), and I keep
marking them as spam over and over. And over. I think something must
be wrong with Gmail's spam detection algorithms, at least for my
account.