If it's looking in the wrong place for current posts, then you did not change it in the config file.
Or are you saying old posts are looking in the wrong place? If so, that's correct, as the body of the post HTML contains the image tag from whenever the post was made.
Alot of people make sure they leave the images directory (or a copy of it) in the same place.
If you want to update the path within old posts with an SQL Query (USE CAUTION - MAKE BACKUPS - YOU CAN NOT UNDO SQL QUERIES), check out omegatron's post in this thread:
http://www.threadsdev.com/forum/showflat.php/Cat/0/Number/94362
