How to Display Google Avatar?

[AvengerDr]

As the title topic says.. How do you configure smf Ads so to display the famous "g" letter as the avatar of the automated post displaying the adsense ads in the message body? I'm sure you have seen it on other forums.

Right now I see the post author as "[My Forum Name] Forums" with no avatar.
How can you change that?

Sorry if it has already been asked..