Glitch CR in new Ubuntu

I installed new Ubuntu (14.04) in my computer and run clonk rage. At once I have glitch.
When i click any key during the game (and menu too somewhere) It executes two times, for example when i click ESC It shows and hides window  concurrently . I dont know why. Game as you can think works on older version of System Ubuntu 12.04 which I used.

Thanks in advance.

I wrote this post here because There isn't appropriate category.

I can dimly remember that it had to do something with the XMODIFIERS environment variable. Dunno exactly though.

Kanibal is correct: unset the XMODIFIERS variable before starting, e.g. in bash

$ unset XMODIFIERS
$ ./clonk

>I wrote this post here because There isn't appropriate category.


Sorry for that, I created one now.

I had this problem too.
Fixed it by changing the keyboard input methods.