[falter]

update: I went so far as moving the code out of "archive/global.php" into "includes/init.php", where $show['search_engine'] is defined.

I replaced:

PHP Code:

$show['search_engine'] = ($vbulletin->superglobal_size['_COOKIE'] == 0 AND preg_match("#(google|msnbot|yahoo! slurp)#si", $_SERVER['HTTP_USER_AGENT'])); 


with

PHP Code:

 /**
    * Return true if visited by a robot.
    */
    function is_robot_visit()
    {
        require_once(DIR . '/includes/class_xml.php');
        $xmlobj = new XMLparser(false, DIR . '/includes/xml/spiders_vbulletin.xml');
        $spiderdata = $xmlobj->parse();
    
        if (is_array($spiderdata['spider']))
        {
            foreach ($spiderdata['spider'] AS $spiderling)
            {
                if (isset($_SERVER['HTTP_USER_AGENT']) AND preg_match("#". preg_quote($spiderling['ident'], '#') . "#si", $_SERVER['HTTP_USER_AGENT'])) {
                    return true;
                }
            }
        }
        unset($spiderdata, $xmlobj);
        return false;
    }

$show['search_engine'] = is_robot_visit(); 


Everything works great!