Doh!

Sorry, I opened my eyes and followed the instructions, and everything went fine (installation-wise), but now I have a problem:
The sort creation date column is there, but I should mention that column "Date of Creation", although it is there, it is not clickable. And in the dropdown options "Sort By", I don't have an option to sort by Creation Date?
Threads still appear to be sorted by most-recently-replied to.
Update: I just went through all the changes I made to make sure I didn't miss something, and everything's there.
Do I need to rebuild something or enable this feature in the admincp somewhere before it becomes active? Your advise would be greatly appreciated to acomplish this.
-snake