Forgot to mention: this problem does not occur in Firefox or Konqueror, and was first noticed in Kile (uses katepart).

I once had a similar problem with a German keyboard on a PC that was setup to use the English mapping. Ctrl + Z was actually on Ctrl + Y, very strange. They keys itself (i.e. while typing) where correct though.

I can't give more info though, as the problem has gone away...

(In reply to comment #1)
> Forgot to mention: this problem does not occur in [Firefox or] Konqueror, [...]

Correction: it does occur in Konqueror as well, e.g., to close a tab, I have to press ctrl-z instead of ctrl-w, but it does not occur in the location and search input boxes.

Here it's the same, and I've never had a qwerty keyboard before. 
Hope this bug will be solved because it's not so good that the program is closed (ctrl+w) instead of the action undone (ctrl+z).

I've reported this bug first in launchpad: https://bugs.launchpad.net/ubuntu/+source/kile/+bug/565262 but it's not a kile problem as mentionned.

The problem with discussions about keyboard layouts functioning is that they
are almost never clear to half the people involved :) So, first of all, take
a look at this random layout:

http://caslav.gmxhome.de/misc/layout-cyr-xkb_rs_latin.html

The important bit on this picture are the internal X key names written at
the bottom of each key, such as AD01, AB09, LSGT... Now:

1) Which layouts do you have in the rotation (i.e. switchable by a shortcut
or click on layout tray icon), and in which exact order (as listed in
keyboard layout settings)?

2) Which layout is currently active?

3) Which shortcut do you press, in terms of internal key names (e.g.
"LCTL+AD02")?

4) Which behaviour do you get, in terms of application (e.g. "the window
closes")?

5) Which behaviour did you expect, also in terms of application?

1) I only use AZERTY (BE) and I have not used another since the installation of my OS.

2) AZERTY

3a) LCTL+AD02
4a) Kate asks to close the document (save the changes?) or close the document if all changes are saved.
5a) I wanted to undo an action

3b) LCTL+AD01
4b) Kate asks to close the editor (save the changes?) or close the editor if all changes are saved.
5b) I wanted to "select all"

3a) LCTL+AB01
4a) undo an action
5a) Normally I would expect kate to ask to close the document. but now I use this to undo an action.

That's nigh impossible if be is really the only layout. Could you paste here
the output from:

  $ setxkbmap -print

[code]
xkb_keymap {
	xkb_keycodes  { include "evdev+aliases(qwerty)"	};
	xkb_types     { include "complete"	};
	xkb_compat    { include "complete"	};
	xkb_symbols   { include "pc+ie+be:2+inet(evdev)+terminate(ctrl_alt_bksp)"	};
	xkb_geometry  { include "pc(pc105)"	};
};
[/code]
It says something about qwerty but I know I'm typing in azerty and all other apps (exept KDE) are listening to the correct hotkeys.

Ok, I've been testing a bit, and it seems KDE apps draw their Ctrl-shortcuts
_from the first layout in rotation. In your case, this line:

  xkb_symbols   { include "pc+ie+be:2+inet(evdev)+terminate(ctrl_alt_bksp)"

shows that the first layout is ie (Irish) and the second be, so Ctrl-
shortcuts are taken from ie (which is a QWERTY layout). You could therefore
"fix" your problem by setting be as the first or only layout.

Now, I don't know whether this first-layout behavior is intended or not
(feature or bug), so I'm adding to CC a person who might know. (Some people,
me included, would consider it exactly the right behavior: that Ctrl-
shortcuts should not change their physical positions on the keyboard as the
user switches layouts.)

(In reply to comment #9)
> [...] it seems KDE apps draw their Ctrl-shortcuts
> from the first layout in rotation. [...]

Great. It seems you've made progress in identifying what is happening here.
My thanks for your effort.

> Now, I don't know whether this first-layout behavior is intended or not
> (feature or bug), [...] (Some people,me included, would consider it exactly
> the right behavior: that Ctrl-shortcuts should not change their physical
> positions on the keyboard as the user switches layouts.)

Well, I would say that this is a bug:
* other behavior in all(?) non-KDE programs
* other behavior in some parts of, e.g., Konqueror (address line, search box, text input fields)
* not taking into account that there are people that switch physical keyboards (like me--I have *both* layouts in my mind and in finger memory, believe me, this behavior can be maddening, most of all because wanting to undo an action can cause closing the text I'm editing without saving, as I encountered more than once in Kile)
* not even allowing the behavior that is standard for all(?) non-KDE programs

I think the solution should be to completely switch the layout as seems standard outside of KDE, but perhaps add an option that allows keeping the current behavior for those who want it.

Still present in 4.5.5, so I guess the lack of further comments is indicative of the attention this bug has gotten since the previous comment. I would be very grateful if this bug got fixed (albeit with an advanced keyboard configuration option). I understand developers have limited time, so is there anything I can do to facilitate things (Info to be added to this report,...)?

*** Bug 316909 has been marked as a duplicate of this bug. ***

Thank you for reporting this bug in KDE software. As it has been a while since this issue was reported, can we please ask you to see if you can reproduce the issue with a recent software version?

If you can reproduce the issue, please change the status to "CONFIRMED" when replying. Thank you!

(In reply to Justin Zobel from comment #13)
> Thank you for reporting this bug in KDE software. As it has been a while
> since this issue was reported, can we please ask you to see if you can
> reproduce the issue with a recent software version?

It seems to have been fixed! (I had fully switched to QWERTY in the mean time, so didn't follow-up.)