EliteGroup WU221 USB with Redhat 9.0

I have installed at76c503 - linux driver for Atmel at76c503 based usb wlan adapters from http://at76c503a.berlios.de/ using instructions in readme but would appreciate some help assigning the IP address.  Situation is as follows:

lsmod shows at76c503-rfmd, at76c503 & usbdfu are loaded although numbers are different to to Readme.

iwconfig lists device as wlan0 however I am unable to set the IP address using iwconfig as suggested in the readme.

Has the method of assigning the IP address changed ?  If so please could some kind soul let me know how to do this.

Thanks all in advance,

James