--- a/mod_register_dnsbl/mod_register_dnsbl.lua	Sun Mar 20 12:38:22 2016 +0100
+++ b/mod_register_dnsbl/mod_register_dnsbl.lua	Mon Mar 21 13:18:04 2016 +0100
@@ -2,7 +2,7 @@
 local rbl = module:get_option_string("registration_rbl");
 
 local function reverse(ip, suffix)
-	local a,b,c,d = ip:match("^(%d+%).(%d+%).(%d+%).(%d+%)$");
+	local a,b,c,d = ip:match("^(%d+).(%d+).(%d+).(%d+)$");
 	if not a then return end
 	return ("%d.%d.%d.%d.%s"):format(d,c,b,a, suffix);
 end