Wireless Connection Problem (XPS M1710)

Hello. Before I moved into my college dorm room my wireless connection was working fine. I was able to surf the net at home without any problems. As soon as i moved into my dorm i had to switch to cable connection. I was required to register to the school network and set up a DNS server connection on my TCP/protocol settings. Afterwards, I tried using IntelProset/wireless. I can connect to an open wireless network without any trouble (good reception). However, I still can't seem to surf the net. Did registering into the school network through LAN somehow alter the settings? If so, how can i get my wireless connection back?