Hexadecimal numeric keypad layout causes several keyboard-layout issues

Reporting this bug for Ubuntu Raring, but it has been present since at least Oneiric.

When the hexadecimal numeric keypad layout is enabled, in any desktop session following the one in which this setting is applied, keyboard layout options are ignored. Changing main-keyboard layouts (if multiple layouts are configured) ceases to be possible, and all options set in the "options" popup of the gnome-control-center Keyboard Layout panel (including, for example, the behaviour of CapsLock, the key(s) for third-level shift state, and the altered numpad layout itself) are ignored. Attempting to change the numeric keypad layout setting back to "Default" does solve the problem, but only after logging out and back in - and, obviously, this does not fix the inability to use the hex-keypad layout.

A possibly-related effect is that even during the session in which the hexadecimal keypad is enabled, the hex digits A through F are not placed as the layout chart suggests - rather than being shifted on numpad keys four through nine, only the digits A through D are available, placed (in order) on 8, 2, 6, and 4 - and affecting the normal arrow keys as well as the ones on the numpad.

The expected result of setting a hexadecimal numeric keypad, of course, is that the capital letters A through F, being also the hex digits A through F, appear in sequence on the numeric keypad keys 7,8,9,4,5,6, and that the main keyboard layout and any other options set remain unaffected, including the ability to change layouts.

Steps to reproduce:

(0: Create a new user account to avoid causing semipermanent problems with any existing user. Removing ~/.config will solve the problem, but this is hardly desirable)

1: Open gnome-control-center (System Settings).
2: Choose the Keyboard Layout settings panel.
3: Press the Options button in the lower-right corner.
4: Under the Numeric Keypad Layout Selection heading, choose the Hexadecimal radio button.
(4a: Observe that the hexadecimal keypad does not in fact work correctly).
5: For ease of effect-observation, ensure that multiple keyboard layouts are configured, and/or other layout Options altered from their defaults.
6: Observe that layout switching and non-default Options function correctly.
7: Log out.
8: Log back in to the account in question.
9a: Attempt to change the active keyboard layout. Observe that this may appear to work in the Indicator, but in fact has no effect.
9b: Attempt to produce the expected behaviour of any altered layout Options. Observe that this behaviour is entirely absent.

(Optional: Try changing the keyboard layout set as primary, or even removing it from the list entirely. Notice that this makes absolutely no difference, and that the keyboard layout remains stuck in the previous primary layout - even through a logout and login)

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: lightdm 1.6.0-0ubuntu2.1
ProcVersionSignature: Ubuntu 3.8.0-19.30-generic 3.8.8
Uname: Linux 3.8.0-19-generic x86_64
ApportVersion: 2.9.2-0ubuntu8
Architecture: amd64
Date: Mon May 6 18:58:14 2013
InstallationDate: Installed on 2013-04-29 (6 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
LightdmConfig:
 [SeatDefaults]
 user-session=ubuntu
 greeter-session=unity-greeter
MarkForUpload: True
SourcePackage: lightdm
UpgradeStatus: No upgrade log present (probably fresh install)