We are going to begin hosting all avatars. Existing avatars are being downloaded/converted automatically. Currently, you cannot submit an avatar but it will be available soon. Some of the animated gifs may not have converted correctly, you can try to resubmit them. In the meantime your avatar may be missing or the link is broken.
Update
Use the Edit Chars page to update your avatar, it's quick and easy +cool. If you don't see your old avatar appearing.. this means it didn't survive the transition to our server. Just resubmit it.
Update 2
For best results, make sure the dimensions of your image is 100x100 pixels. Otherwise, the image will be resized/cropped accordingly.
Post here if you discover a problem.