The default user picture set on the user settings page (/admin/user/settings) does not show up for user comments. "Users picture in comments" is enabled and the default picture is appearing on user account pages. If I comment out the following code in template.php the default picture shows up:

  // if user has no picture, add in a filler
  if (theme_get_setting('toggle_comment_user_picture') && empty($vars['comment']->picture)) {
    $vars['picture'] = '<div class="no-picture">&nbsp;</div>';
  }

Can this be changed to check for the default picture setting? (I'll try and look into this if I can...)