Using special keys on a keyboard

[Thibaut Cousin <cousin@in2p3.fr>]

Hello,

  I recently got a new keyboard with several special keys to power off the
computer, launch the mailer, etc. I'd like to make them work under Linux (I'm
using Potato).
  When I press them at boot time, I get on screen a message "unknown scancode"
with a code "e0 xx". But I fear these codes are only for the console, not for
X. So :
	- how do I get the codes of these keys for X ? xkeycaps doesn't work,
	  as it only knows standard keyboards.
	- where can I configure their action ? Is there a tool to do it ?

-- 
Thibaut Cousin
email : cousin@in2p3.fr