With KNOPPIX 5.1.1, the "zd1211rw" module is included, but it doesn't work because the firmware is not included. You can see the error message by removing and adding the module explicitly:

modprobe -r zd1211rw
modprobe zd1211rw

For further information, and to obtain the firmware, see:

http://zd1211.ath.cx/
http://sourceforge.net/project/showf...roup_id=129083

The README in zd1211-firmware1.3.tar.bz2 mentions GPL, so probably it should be included with KNOPPIX. If for some reason it can't be included, then you might as well remove the driver, because the driver is no use without the firmware, as far as I can tell.