[Admin]

Try this.

In register.php, replace this:

        if (!$avatar['title']) {
		  $avatar['title'] = $avatar['avatarpath'];
		  if (strstr($avatar['title'], '/')) {
		    $avatar['title'] = substr( strrchr($avatar['title'], '/') , 1);
		  }
		  $avatar['title'] = str_replace('_', ' ', $avatar[title]);
		  $dotpos = strrpos($avatar[title], '.');
		  $avatar[title] =  substr($avatar[title], 0, $dotpos);
        }
        eval("\$avatarbits .= \"".gettemplate("register_avatarbit")."\";");

with this:

        if (!$istaken=$DB_site->query_first("SELECT userid FROM user WHERE avatarid='$avatar[avatarid]'")) { 
          if (!$avatar['title']) {
		    $avatar['title'] = $avatar['avatarpath'];
		    if (strstr($avatar['title'], '/')) {
		      $avatar['title'] = substr( strrchr($avatar['title'], '/') , 1);
		    }
		    $avatar['title'] = str_replace('_', ' ', $avatar[title]);
		    $dotpos = strrpos($avatar[title], '.');
		    $avatar[title] =  substr($avatar[title], 0, $dotpos);
          }
          eval("\$avatarbits .= \"".gettemplate("register_avatarbit")."\";");
        }

this should work.