You should be able to find some information in your log files and possibily dmesg 

My guess is you are missing some modules for iptables in your kernel. 

----- Original Message ----- 
From: "Ajai Khattri" <ajai@bway.net> 
To: gentoo-server@lists.gentoo.org 
Sent: Monday, September 22, 2008 7:16:06 AM GMT -06:00 US/Canada Central 
Subject: [gentoo-server] Iptables Changes 


After a recent kernel + iptables update I now find that iptables fails to 
start with my saved rules. All it says is that the final COMMiT 
line fails. Is there a way to troubleshoot this without typing each rule 
by hand? Maybe some debug / verbose flag? 


-- 
A