inserting default comment avatar

Can you help me correct the missing default avatar? I have one uploaded in Comments Plus settings [16x16], but I'd been having problems with the WP comment avatar since trying to hack my custom.php file. I deleted the hack, but the mystery man and other WP avatars were never restored.

Here is a post with comments using Comments Plus.
http://lovelinkin.com/2011/12/02/lovelinks-33-winners/

Thanks for the help!

Erica
lovelinkin.com