You need to be a subscriber to upload a profile picture.
Yes, profile picture, avatar, whatever you want to call it, the picture that shows to the left on your forum posts is what I assume you meant.
See here for details about what you get for subscribing: http://www.enworld.org/forum/payments.php
I think this thread mentions when the change happened; http://www.enworld.org/forum/showth...lse-having-any-issues-posting-a-profile-photo