Right now, my PM notification at the top of the page says “0 new messages, -1 unread messages”.
What does -1 unread message mean? 
Hm, I’m not sure. Are there any PMs in your Inbox that are still highlighted / bolded?
that’s easy!
you have read a message that doesn’t exist
-OR-
it works like yer total post count
what is not always the same number
as the count of all of yer posts
Nope. No unread messages going in or out. Maybe the PM police caught me reading one twice. 
Not an important issue. I just wondered if anyone knew what it meant.
Denny, I like your reason. The Chiff has always seemed a bit like an alternate universe. It could happen!
they fixed a lot of things in the database with this release…I don’t know if they got 'em all 