to get it work by start up your session, add
xmodmap Xmodmap-my &it in a script on your autostart folder.
LXDE users can have it simpler, open lxautostart from lxdecc, or start>More Applications>Configuration>...
Click on Advanced button, OK button, and paste the follow command in the entry line.
xmodmap Xmodmap-my &Click on Ok, log out/in that's all
