First,make sure the picture is of a suitable size (e.g. 80 x 120 pixels)
Then click on "profile" at the top of the page,go to "avatar control panel" at the bottom,delete the existing one,then paste the url into the "link to offsite avatar" box.
Must be reasonably easy - I managed it without having to resort to getting my teenage son to do it for me.. :wink:
Andrew