NM drops WPA connection

[Marcello Musso <musso physics utexas edu>]

Hi,
I have network-manager 0.6.5 installed on Ubuntu Gutsy. I use a Broadcom 
4318 wireless card with Ndiswrapper.
Everything used to work fine, but now if I try to connect to a WPA 
encrypted wireless network then I am disconnected after a few minutes.
The nm-applet in the system tray still says I am connected, but I have no 
networking whatsoever. 
When I ping an IP address, it looks for it but cannot find it.
Everything still works (almost) correctly with unencrypted wirelesses.
Any suggestion?
    Many thanks
        Marcello
************************************************
*  Marcello Musso                              *
*  University of Texas at Austin               *
*  Department of Physics - Theory group        *
*  1, University Station C1608                 *
*  Austin, TX 78712-0269 - USA                 *
*  office phone: (512)-471-4108                *
*  VoIP phone: +39-02-303129852                *
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