setkeycodes fail - invalid argument

[Mika Anttila]

When I in Kubuntu 12.04 in console I enter for example
sudo setkeycodes 56 42 (to reassign a key to become a left shift)
or any other scancode - keycode combination I have tried,

I always get:
"KDSETKEYCODE: Invalid argument, failed to set scancode 56 to keycode 42" on the console.

I can reproduce this also on a Debian 7 stable on a different hardware.

I believe I am using the setkeycodes according to the man pages.
The first argument is in hex and the other in decimal.

The keyboard is connected via a USB port if that information has any value.

setkeycodes belong to the package console-tools, I suppose.