What steps will reproduce the problem?
1. Write a comment on a Wordpress blog with openid
2. Authenticate using openid

What is the expected output? What do you see instead?
Currently a default avatar is shown when commenting using openid.
The commenters gravatar should be shown.

What version of the product are you using? On what operating system?
OpenID 3.3.3 plugin for Wordpress 3.0.5

Please provide any additional information below.
At this point the openid protocol does not support avatars.
However, it is possible in the openid exchange to get hold of the users e-mail 
address (openid.ax.value.email). Using that address you can check if a gravatar 
is available and display the picture.