Connecting to my XBOX360 using macbook wifi

Hello there,
I was wondering if anyone had any ideas about this , I am completly stuck.

My router is connected to my macbook via ethernet. My xbox has a wireless adapter. I am tryig to connect the macbook to the xbox using the internet sharing on the mac so that I can get onto xbox live. I have tried manual configurations of the xbox , it can see the broacast name but cant get any further. I'm pretty sure the manual IP addressi have configuerd onm the XBOX is correct because i can use the internet on my iphone from my macbook .. and checking the router ./ DNS settings are the same .. the only differnce is i have given the xbox a differnt IP ,

please anyone with anyideas would be greatly appreciated ..

Thanks
Simon

Am I correct in assuming that the router you speak of is not a wireless router? If not, I would consider upgrading to a wireless router instead. Using the Mac as a wireless access point adds a degree of complexity to an already difficult configuration.

the xbox requires a router of some sort and as far as I am aware the mac wont provide traffic routing and NAT which the xbox needs for live.

Get your self a cheap dlink router like the 524 which will do the job for you.

I succeded in doing something like that by running the following script (instead of using Internet Sharing):
*********************************************
sysctl -w net.inet.ip.forwarding=1
natd -interface ppp0
ipfw add divert natd ip from any to any via ppp0
*********************************************
likely you have to change from ppp0 (the connection name of my USB mobile modem) to en0 (ethernet)
Wireless addresses fo MAC (en1) and XBOX must be set manually unless the XBOX wireless adapter has a DHCP, I suggest 10.0.2.1 on MAC and 10.0.2.2 on XBOX but any value other could be Ok