nastroika XKB v iksah 4.2.0

ne mogu nastroit' xkb, lubaja zapis' v XF86Config svazannaja s XKB vydaet error.
vot 4to ja pihu:

Section "InputDevice"
       Identifier  "Keyboard0"
       Driver      "keyboard"
       Option "XkbRules"       "xfree86"
       Option "XkbModel"       "pc104"
       Option "XkbLayout"      "ru"
       Option "XkbOptions"     "grp:ctrl_shift_toggle"
EndSection

a pri popytke nastroit' eto delo iz xf86cfg on soobhaet 4to 'file xkb rules not found'
pomogite plz, zaranee spasibo.