[kh99]

Sorry for the late reply, if you're still working on this, I think you could use code like this:

	$strikes = $vbulletin->db->query_first("
		SELECT COUNT(*) AS strikes, MAX(striketime) AS lasttime
		FROM " . TABLE_PREFIX . "strikes
		WHERE strikeip = '" . $vbulletin->db->escape_string(IPADDRESS) . "'
	");

	if ($strikes['strikes'] >= 5 AND $strikes['lasttime'] > TIMENOW - 900)
        {
           // This ip address currently has 5 strikes (against any username).
           // Do something here
        }

So you could put that in a plugin, maybe using hook global_start, and set a variable to be checked in a template or something like that.