[Sephirot]

I recently got the following error

[Thu Jul 23 17:45:00 2009] [error] [client XXXX] PHP Fatal error:  Maximum execution time of 240 seconds exceeded in /srv/www/htdocs/vbulletin/includes/class_activecache_methods.php on line 355, referer: XXXX

PHP Code:

    function set($title, $item)
    {
        if (!$this->connect())
        {
            return false;
        }

        $this->set_title($title);

        if (trim($item) == '')
        {
            $item = '{_______VB_ACTIVE_CACHE_BLANK_______}';
        }

        eaccelerator_rm($title); // this is the line from the error log
        eaccelerator_put($title, $item);
    } 


Any ideas about the cause?