Strange keyboard-error while playing

This problem occurs while I'm ingame in Wolfenstein: Enemy Territory.
I use the Logitech G15 keyboard.

When I try to type either Æ, Ø or Å (norwegian characters) in Wolfenstein's chat, they doesn't appear.
If I want to type for example "jaså" it shows as "jas", I simply can't type æ, ø or å.
And it isn't a bug in the game, since I can write æ, ø and å without any problems in the windows version.

Also, when I press the key "ALT", it normally shows stats.
Now that I press ALT, it shows stats, but the stats is still there after I've unpressed ALT.
Basically what happens is that once I've pressed ALT, it will still be pressed, even after I've unpressed it. (bad English by me, but hope you understand)
That error is also only happening when I'm playing Wolfenstein. While I'm back in Ubuntu, the ALT-key works as normally.

Neither of these errors happens in the Windows version of Wolfenstein.