This only works for 32bit linux. And I can't gurantee about 64bit ubuntu machines.

Clean up previous installations of ath drivers and ndiswrapper.

First add following lines to your /etc/modprobe.d/blacklist file.

blacklist ath_pci blacklist ath_hal

Now delete files left by previous installation of ndiswrapper.

sudo rm -fr /etc/ndiswrapper/

Now open System >> Administration >> Hardware Drivers and disable all atheros drivers.

Install ndiswrapper

sudo apt-get -y install ndiswrapper-common

Download 32 bit driver. Extract the archive and execute following command from the folder where you extracted the contents.

sudo ndiswraper -i net5211.inf

Use following command to see whether the driver is correctly installed.

sudo ndiswrapper -l

Execute following command.

sudo ndiswrapper -ma

Now add following line to the file /etc/modprobe.d/ndiswrapper at the end.

alias wlan0 ndiswrapper

Reboot and enjoy using your wireless lan network.

Seems like this fix is working with following machines.