Does your campus netwowrk have any requirements in terms of PPTP, or some form of LDAP login? A lot of campus wifi networks are "powered" by a solution called BlueSocket, which often requires some weird authentication methods to gain access.
Depends on how they have it set up. In the simplest (and thankfully most common) implementation, you connect and the first page you access will be an LDAP login (usually involving some sort of school e-mail or campus id login, commonly called a "NetID"). Enter that and your password, and you're authenticated.