Difficulty connecting to a WPA2 Enterprise network, then disconnects after 20-30 minutes

Question

My University is using a WPA2 Enterprise network, it has these properties:

Authentication: PEAP (Version 0)
Inner Authentication: MSCHAPv2

Connecting to the wifi is almost impossible all the time. But sometimes it does connect. But only stays connected for 20-30 minutes, and then disconnects.

I'll post the output of nm-tool too, just in case. (While connected to the Home network, it gives no trouble).

When searching the forums, it seemed that this was a common issue, but through hours of searching I couldn't find a solution. If anyone knows of any fix, please let me know.

• Output of nm-tool follows.

  - Device: wlan0  [Home] --------------------------------------------
  Type:              802.11 WiFi
  Driver:            iwlagn
  State:             connected
  Default:           yes
  HW Address:        AC:72:89:3A:71:95
  
  Capabilities:
    Speed:           54 Mb/s
  
  Wireless Properties
    WEP Encryption:  yes
    WPA Encryption:  yes
    WPA2 Encryption: yes
  

• Output of: uname -a

Linux vostro 2.6.38-11-generic #48-Ubuntu SMP Fri Jul 29 19:02:55 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux