Comment 30 for bug 313514

It looks like X will not regard mappings above 255 and therefore a better way to solve this is with HAL keymaps. Not having much luck here though. I set a map for the keycode and the scancode,

root@gimble:/usr/share/hal/fdi/information/10freedesktop# lshal | grep keymap
  info.callouts.add = {'hal-setup-keymap', 'debian-setup-keyboard'} (string list)
  info.capabilities = {'input', 'input.keys', 'input.keymap', 'button'} (string list) = {'377:wifi', '001c:wifi'} (string list)

but xev is not seeing those events.