I have eduroam working in my N900. My settings are:

SSID: eduroam

Network mode: Infrastructure
Security method: WPA with EAP

EAP type: PEAP

Select Certificate: None
EAP method: EAP MSCHAPv2

User name: ...@...

Now, very important, go to Advanced -> EAP tab

Use manual user name: checked
Manual user name: ...@... (same as User name)