port forward / port changing

Hi all

I have my router set up to port forward various ports across, eg

ExtIP:25 -> Mail:25 ExtIP:80 -> Web:80

but I cant figure out how to make the ports different. Eg i have another interal web server which i want to make available externally...

ExtIP:8000 -> OtherWeb:80

what is the exact command for this?

I've tried ip nat inside source static tcp 192.168.176.150 80 interface Dialer1 8000 but I dont seem to be getting anywhere. It's an 827 running IOS 12.3(15).

Thanks Mike