When I write letter " " (space) with czech keyboard layout, everything is correct.
When I switch into english keyboard layout, the letter " " is written correctly on
screen, but probably has wrong ascii number.

How to reproduce:

1) Open e.g. kate text editor and create file a.txt and b.txt.
2) Write one space (written with spacebar on keyboard) with czech keyboard into file a.txt and save it.
3) Write one space with english keyboard into file b.txt and save it.
4) run cmp a.txt b.txt and you will see they are different.

Another method how to reproduce:

1) Open xterm
2) Write echo Hello with czech keyboard. You will get Hello.
3) Write echo Hello with english keyboard. You will get 
bash: echo Ahoj: command not found