[kh99]

If I remember correctly, the filename field is the name of the file that was uploaded. But I think the '0' in avatar33_0.gif is the avatarrevision field from the user table. I hink it's added when you store files in the filesystem so that if, for example, Jim uploads a new avatar with the same name, the avatar revision will be increased so that the new file has a different name and people's browsers will load the new image instead of continuing to see a cached image.

But I don't know why you're not seeing Jim's avatar. There should be a file with that name (with the _0) in the customavatars folder.