this also depends on how the settings were done. you could try to get another ip by reconnecting to the router. there is a way to spoof your ip to the router. to do it, im not sure yet. from what i kno the DHCP assigns you that address. i would be pesimistic on getting a new ip since admins can control how many clients can be hooked up; it really depends on exactly how he restricted you. Another way would be to go hard lined and hook up to your router to get a new ip assuming if its a wireless router, but that leaves you with a cable to deal with. Next in line, controlled trojans/keyloggers are your next best weapon :P.

correct me if im wrong.