Uwe Brauer wrote:

> Potential causes:
> * Insufficient permissions
> * NetworkManager not running
> * DBUS failure
> 

Have you eliminated those three issues?

> 
> I consider the failure for WPA Enterprise as a serious bug and I know it
> did not happen for example in Ubuntu 10.04+relevant trinity version.

If so file a bug report with some information on how to reproduce it.

regards