Gerix wifi cracer doesnt work every time. But if you can use commandlice, where you need a gui.
To install grimwpa go to grimwepa - Project Hosting on Google Code download grimstall.sh and grimwpa_1.0.jar to your desktop (in BT4 /root/ ) in BT4 you are probably are root, if not use "sudo su".
then type in commandline
and answer those questions.Code:chmod +x grimstall.sh ./grimstall.sh install
Now you are installed grimwpa.