Günther Grass in der Zeit: Mündig sein

The reason is that the Xorg now uses HAL to automatically configure your plugged-in devices.

The solution lies in /usr/share/hal/fdi/policy/10osvendor/10-keymap.fdi :

If you want to add a custom model/layout/variant to X, you will need to COPY
this file to /etc/hal/fdi/policy/ and edit that copy.  After editing it to
suit, you will need to leave X, restart the HAL daemon, and start X again.

Here is my example for a german keymap:

<merge key="input.xkb.rules" type="string">xorg</merge>
<merge key="input.xkb.model" type="string">evdev</merge>
<merge key="input.xkb.layout" type="string">de</merge>
<merge key="input.xkb.variant" type="string">nodeadkeys</merge>

You can test if the settings fits your needs with:

setxkbmap -model evdev -rules xorg -layout de -variant nodeadkeys

You can prevent HAL from configuring your devices in general by adding:

Option   „AllowEmptyInput“     „false“
Option   „AutoAddDevices“      „false“
Option   „AutoEnableDevices“   „false“

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