I've just installed Debian Lenny in my laptop and KDE4 from backports on it. When I first launched KNetworkManager for connecting to my WPA2 wireless network KNetworkManager said that no devices where available. The big surprise came when I checked it out in a shell and confirm that no wireless device was found (after installing wireless-tools). So I remember about some issues with the firmware. In Debian the firmware is not included because its licence, so you have to download it separately from the Intel ipw2200 website and copy it to /lib/firmware. After that, what I needed to do was to add my user to the netdev group in order to be able to manage the network configuration through KNetworkManager. With these things done, I'm now writing this post using my wireless connection :)
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