I spent two full days to get my iMac online using AirPort but without success. Finally I gave up and use cable. However, ocasionally the Mac will unable to connect to Internet. I will have to unplug and replug the cable several times before it can hookup again.
Tonight, I used miniStat2 widgets to connect via AirPort, accidentally. It is a monitoring program, in Dashboard. Actually, I seldom use them, except when I try to set up an alarm clock at the ProdMe 0.7b. But I ain't sure why it can make connection possible. A mircale, anyway.