Something's wrong with the sorting of Forum's topics [solved]

Seems like they are not sorted and highlighted by the time created, being read and so on....
Or is it just me?

They still work as intended. Spammer used some very old threads, and these were pushed to first places as unread. His posts were deleted, but posts stayed unread for users. And you cannot see them because they moved back into forum history.

Ah, I also wondered what that was. Jarcek's comment explains everything. Thanks for a quick fix.

After making sure I read everything that was truly new I just clicked "All Read" button and everything got cleared up.