Easiest just to do the following;
1) Find the site that's getting flagged ((membres.lycos.fr in this situation))
2) Go past the warning.
3) Press CTRL + U on your PC to open up the source code.
4) Press CTRL + F to open the quick find menu at the bottom of your browser.
5) Search for the flagged site in the source code and find out who has the avatar.
6) Get the member name, edit the delete avatar URL, and delete their avatar.
Problem solved for everyone.