Avatars not showing

I've installed Avatars and added an Avatar for my user/blog, but the Avatar does not show.

In Firefox the missing image is just not shown (giving me a false impression of everything being alright) but in IE7 you can clearly see the missing picture red X.

I've added the .htaccess rewrite rule so I don't feel that it should be that, but since it seems to be related to the link I feel that's what it must be.

Any thoughts/suggestions would be helpful ,