I think that user was deleted, so the geekmail probably went along with them.
uHM... Good deduction.
It's just a bit annoying the red "1 new", but I can live with it
Still a bug though. If the user and its mail get deleted (presumably by an admin) then so should all mail in user's inboxes and all references to them. If this doesn't happen then the whole system will collapse under the weight of kipple.