Win 2000 Internet sharing

[raf]

Have Win2000 connected to my XP machine.....network has access to all drives etc. but can't get the internet connection thru my XP machine to work. Used help on the Win2000 machine to configure but the option for internet connection sharing is just not there. Win2000 Laptop is on the network and has the option. Am I missing something simple? Its a dial up with the XP machine connected to the phone line.

Thanks
Randy