does anyone know how to release & renew IP addresses from the terminal app? kinda like the unix (OS X) equivalent of windows "ipconfig /release" & "ipconfig /renew". i thought ifconfig was the command line utility to do it however, i just can't seem to find the right parameters to make it work? i'm tired of having to go to the Network System Preferences window to do the task. i usually have terminal open and i'd REALLY like to be able to do it from there. any ideas?