i got Linksys wrt54gl v1.1 and ddwrt DD-WRT v24-sp1 (07/27/08) mini(SVN revision 10011) firmware. The game won't give me NAT Open whatever i do.. I tryed DMZ, upnp, port forward but nothing. Firewall is turned off in windows so i guess the firmware is bugged...
Anyone had same problems? All other games and port forward work OK so dunno what so special about MW 2
Apologies but I don't play that game, however that version of DD-WRT is rather old and also suffers from a security issue which allows a person on the WAN side remote control of the router. Details: »www.dd-wrt.com/site/content/dd-w···m-report
IMHO would update the firmware to fix the security issue, hopefully it will allow you to get online with Call of Duty.