I searched the forums and didn't find an answer for this, so I thought I'd post both the problem and the solution I found [with a little help from a friend].

Problem: Sharing an ethernet connection via my G4 PowerBook's AirPort card and OS X's Internet Sharing. I was getting an IP address, but couldn't connect to anything [web, IRC, news, etc.].

Soultion: I ended up having to manually assign an IP address to wlan0 [the one that was being done automatically was on wlan0:1 for some reason] and then assign the default gateway manually.

Assuming that the AirPort interface has an IP of 10.0.2.1, these are the commands I used on the 770:

You need to have xterm installed and root enabled to do this. I bundled it all up into a shell script, did a chmod a+x, and put it in my home directory. I hope someone finds this is helpful, and if someone has a better way to do it, I'd love to hear.

This can also be done from the Control panel, editing your shared wlan connection from connectivity/connections. After clicking 'next' a few times, you get to the advanced options. No need for xterm, root or the likes :) Just set the IP of your 770 manually, as well as router, dns and subnet.

Here's what I had to do to get my 770 to connect to the Shared Internet connection from the Airport card in my Mac Mini.

On the Mac, open a terminal and type "ifconfig en1". The inet address, 10.0.2.1 is the router, for your IP just increment this a digit or two, while the netmask is 255.255.0.0. To get the Primary DNS, type "dig". At the end of the output is a SERVER line, jot down the IP there.

On the 770, open Connection Manager and go to Tools>Connectivity Settings. Then select Connections, choose the connection, click edit, click next a few times until you get to the Advanced tab. There, uncheck Autoretreive and fill in the above under IP Addresses.

Worked like a charm.
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