i am having the same issue. i have a dlink card using ndiswrapper and dhcpcd wont work either, same problem as OP
ndiswrapper -l shoes driver installed and device present. i'm running a modified net8180.inf file which i modified to work with the dlink card as its actually a realtek chipset (found this info on the net and it worked flawlessly on slackware 12.0, the original dlink driver locked up every time w/ndiswrapper)
i also tried installing and running dhclient with the same symptom.. it sits there for a bit then nothing happens.
how can i obtain address from dhcpcd, all it does is sit there, time out, and remove wlan0 from ifconfig. i modified the ifplugd.conf file as instructed in the wireless howto in the forum here.
i had this card/ndiswrapper setup working perfect in slackware 12.0 and dhclient
i do not have any encryption and the card sees the access point's essid and mac.
also: i had the same issue with the original ndiswrapper driver that was initially installed after setup, netldl i think. same symptoms: driver installed/device present, dhcpcd timed out and did nothing)
just wanted to say this problem is gone now, i dont know what fixed it but here's what happened
modified ifplug.conf, rebooted, modprobe ndiswrapper, iwlist scan, iwconfig wlan0 essid essidname, dhcpcd wlan0