Had a lot of issues with my 802.11 intel 4965AGN wireless card towards WICD.
All from beeing stuck at obtaining ip, bad password, cant connect to hidden networks.
Seen a lot of similar topics, but with no answear
So I decided to give gnome network manager a chance.
This fixed the problem for me
apt-get install network-manager-gnome
$nohup nm-applet &
(if it shows: Network manager Error - Device is Unmanaged)
Change "managed=false" to "managed=true"
For autostart nm-applet on X:
cp /etc/xdg/autostart/nm-applet.desktop ~/.kde3/Autostart