I am trying to use a WMP54g (v2 with the Broadcom chipset) with FC3 and ndiswrapper 0.12.

First, the easy part. I set up the device to use wlan0 in /etc/modprobe.conf. I manually created an /etc/sysconfig/network-scripts/ifcfg-wlan0 file. Next I set the network to use WEP encryption and manually created an /etc/sysconfig/network-scripts/keys-wlan0 file. Up to this point everything worked properly.

Now the hard part. I installed wpa_supplicant 0.2.6 and changed the network to WPA-PSK. But when I try to run

wpa_supplicant -Dndiswrapper -iwlan0 -c/etc/wpa_supplicant-0.2.6/wpa_supplicant.conf -dd

I get an error message

Unsupported driver 'ndiswrapper'

and when I reboot it can't find the SSID, I get the error that says

Determining IP information for wlan0... failed: no link present. Check cable?

Having gotten this far is right at the limit of my understanding and I have no idea whwere to go next.

You followed these directions exactly?
http://www.linux-wireless.org/Wirele...tall-HOWTO.txt

I have solved my problem with the driver -- it was due to an error in the .config file.

In the meantime, I have actually gotten the card to work (when it feels like doing so -- sometimes the WPA authentication just will not hook up) using the following series of commands:

ifconfig wlan0 up
wpa_supplicant -iwlan0 -c/etc/wpa_supplicant-0.2.6/wpa_supplicant.conf
dhclient wlan0

There are just two little problems.
(1) I have to run this sequence every time I start the machine (which I can live with if I have to)
and
(2) I can only run these commands as root (otherwise I get "command not found"), so I can never access the network as myself. I feel as though I must be overlooking something really obvious but I don't know what...

Try putting those commands in /etc/rc.d/rc.local file.

putting the commands into rc.local caused the machine to hang during bootup, but changing the entry in ifcfg-wlan0 to ONBOOT=no seems to have fixed that problem. I am still having problems with DHCP; I am working on that.