ventouxfinisher on "Why does the Gravatar widget on my blog just show a weird green square?"

I have exactly the same problem as this person:

http://en.forums.wordpress.com/topic/gravatar-logo-together-with-my-pictures-list?replies=2

I tried everything suggested, and also tried clearing cache and waiting 24 hours. Didn't help. I've contacted Gravatar support (twice) and they haven't got back to me. If I go to view my Gravatar profile, the default image for me is the Gravatar logo. Help!!!