You've to edit your XF86Config file located at /etc/X11. Find the section "Input Devices" and keyboard there. When you find that section, include the following line:
Option "XkbLayout" "se"
The last two characters ("se") changes your Keybord for a swedish layout. Find the correct characters for your keyboard. Linux is case sensitive, so make sure to type upper(lower) cases correctly. Make a backup of your XF86Config, just in case
When done, restart X..