--- a/includes/functions.php	Wed Sep 10 06:57:54 2008 -0400
+++ b/includes/functions.php	Tue Sep 16 08:20:14 2008 -0400
@@ -2570,9 +2570,9 @@
 
 function is_valid_ip($ip)
 {
-  // These came from phpBB3.
+  // This next one came from phpBB3.
   $ipv4 = '(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])';
-  $ipv6 = '(?:(?:(?:[\dA-F]{1,4}:){6}(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:::(?:[\dA-F]{1,4}:){5}(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:):(?:[\dA-F]{1,4}:){4}(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:){1,2}:(?:[\dA-F]{1,4}:){3}(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:){1,3}:(?:[\dA-F]{1,4}:){2}(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:){1,4}:(?:[\dA-F]{1,4}:)(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:){1,5}:(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:){1,6}:[\dA-F]{1,4})|(?:(?:[\dA-F]{1,4}:){1,7}:))';
+  $ipv6 = '(?:[a-f0-9]{0,4}):(?:[a-f0-9]{0,4}):(?:[a-f0-9]{0,4}:|:)?(?:[a-f0-9]{0,4}:|:)?(?:[a-f0-9]{0,4}:|:)?(?:[a-f0-9]{0,4}:|:)?(?:[a-f0-9]{0,4}:|:)?(?:[a-f0-9]{1,4})';
 
   if ( preg_match("/^{$ipv4}$/", $ip) || preg_match("/^{$ipv6}$/", $ip) )
     return true;