Well dreg , optus actually make it easy to connect to the net, you don't need any third party app to log onto the net, its all set in your system prefs. Easy as .
But one thing, when they come out to install everything turn it over to OS9, then copy the settings into OSX, they don't deal with OSX yet.
If you want some more info on it, ask Beej he has optus cable, he can help you with anything