Linux dhcp problem

I just installed Mandrake 9.1 on my machine in a dual boot setup with WinXP. And i connect to the internet through a Linksys wireless router. And whenever i boot into linux, the router won't assign my computer an ip. I was able to figure out why it was not doing this. Because they weren't on the same subnet, the router uses a 255.255.255.0 subnet and my ethernet's subnet was set to 255.255.0.0. So when i changed the settings via the mandrake control center and everything was fine.

However, i have to do this everytime i boot into linux. I was wondering what i would have to do so that the router will assign an ip when it boots.

Also how to i change to gdm as my default login manager?

Thanks in advance.

bump

it sounds like you are trying to do two things, set a static address, and get a dhcp address.

In your network config, you want to tell it DHCP, and nothing else. Then, at boot, it should try to get an IP from the router.

You can try manually by typing: dhcpcd (DHCP Client Daemon) at the command prompt, and that will go, get an IP, and assign it to your interface, regardless of what your subnet is set to.