I am using WRT54G , and I dont even need to port forward to allow MSN Messenger to work. If i enable it , MSN Messenger signs on really fast , if I disable it , it just takes 15-20 sec to sign on. Why not try to enable uPnP on , just to see that if that thing works or not. If it does not , then you should disable it

Oh , I am not sure if your Frimware supports Static DHCP or not. But DD-WRT does

So all you have to do is put your MAC Address of the PC , and then the router will assign a Static IP to it. Everytime , you dont even have to set it in your PC. The router does that for you