OK, sorry it took me a while to respond, I had a fight with Ubuntu 12.04 running in a VM so gave up and installed it on a USB stick.
Anyway, the good news is that the Debian instructions seem to work just fine (with slight modification) … I can’t test them with a WG111T as I don’t have one but the module and firmware seems to build/install properly.
OK, let’s get on with it eh ? …
If at any stage during this tutorial you see an error after running a command … stop … and tell me which command caused it, and post the output from that command.
First lets make sure your system is up to date:
sudo apt-get update
then
sudo apt-get upgrade
Now REBOOT.
When the system comes back up, open a terminal and run:
sudo apt-get install build-essential debhelper module-assistant quilt subversion wget wireless-tools
and if asked, hit “y” to accept all the packages … then run:
svn co svn://svn.berlios.de/fullstory/ar5523/trunk/ ar5523
then
wget http://verein.lst.de/~hch/ar5523.tgz
then
tar -xvf ar5523.tgz ar5523/uath-ar5523.bin --strip 1
then
cd ar5523
then
dpkg-buildpackage -us -uc
then
sudo dpkg -i ../ar5523-source*deb
then
sudo m-a a-i ar5523
then
sudo mv -v ../uath-ar5523.bin /lib/firmware
Now load the driver with:
sudo modprobe ar5523
And with a bit of luck your wireless should spring to life 
Please let me know if it works … so future readers will know.
We may have to add those 3 lines from earlier to /etc/modules … to make it hot pluggable (but we’ll decide that once the drivers/firmware are installed and working)