Can't authenticate in South Korea

Hi,

I setup my router and it is working beautifully. The problem is that,
with the ISP I'm using in Korea, I'm expected to log in with supplied
credentials on a webpage before I can start surfing. When I hook up a
computer for the first time and browse to http://www.google.ca, i get
redirected to their login page where I then authenticate and then am
able to browse. But when I hook my router up, I can't enter those
credentials on the webpage the router is being directed to.

It is a cable line, and name servers and the gateway are being
registered when I use DHCP.

Anyone have any ideas??

Thanks,

Chris