iPhone not loading web pages over wifi

Girlfriend has a new iPhone, and it connects to wifi no problem. It was working at my place all weekend. She goes to her place, and it connects to wifi, but web pages aren't loading. iMessages works fine. Her old iPhone loads web pages fine.

Have tried powering off/on, tried "forget this network," but the problem persists. Any ideas?

 

A bit more info. Apparently this wireless network is open in that anyone can connect to it, but has web-based login/password. So it's connecting, but the web-based authentication page isn't loading.