How do I change the login manager's keyboard layout?

I have a netbook with an AZERTY layout. I've changed it to "bépo" to try it, but now I've reset it to a french layout.

While all the apps have taken the change into account, Ubuntu's login manager still uses bépo, making entering passwords a challenge. I've enabled the virtual keyboard for the time being so that I could login again.

I don't remember what I had done in the first place to switch the login screen to bépo, but now I can't switch it back.

EDIT : In the keyboard settings page, if I click "use system defaults", then everything is in bépo ! Where is this different keyboard layout set ?

ANOTHER EDIT : Here's what did not work :

1. Changing the layout in settings
2. using the "use system defaults" checkbox in settings
3. sudo dpkg-reconfigure keyboard-configuration
4. changing it in Xconf
5. adding a line in /etc/lightdm/lightdm.conf
6. sudo dpkg-reconfigure locales
7. slaming head against desk
8. dpkg-reconfigure lightdm
9. sudo gsettings set org.gnome.libgnomekbd.keyboard layouts "['fr']"
10. combinations of the above

Is it possible to relaunch the keyboard configuration tool that's in ubuntu's setup ? The thing has automatic layout detection and it changes the setting everywhere.

What did seem to work for me was this suggestion: change /etc/default/keyboard.

Banging head on desk indeed, this is ridiculous.

From terminal, run the following command to set the language layouts (you can set maximum four layouts) for your lightdm login screen:

gsettings set org.gnome.libgnomekbd.keyboard layouts "['us\taltgr-intl', 'fr']"

With the above command you set English (International) and French layouts, but you can change them as you wish.

To see the current layouts, you can use:

gsettings get org.gnome.libgnomekbd.keyboard layouts

Now, you should be able to use the keyboard icon from the top-right of your screen:

Next is a screen capture from my login screen (I used gsettings set org.gnome.libgnomekbd.keyboard layouts "['us\taltgr-intl', 'gr', 'ro']" in terminal). As you can see, I can change the language layout as I wish:

Must have been a weird lightdm bug.

Lightdm got the new keyboard layout once I changed the login manager to gdm, then back to lightdm, even though simply doing dpkg-reconfigure lightdm did nothing.

So here it is :

sudo apt-get update
sudo apt-get install gdm

(set gdm as the login manager when asked)

sudo dpkg-reconfigure lightdm

(set it as the login manager when asked)

sudo apt-get remove gdm

Then, restart.

Changing a keyboard layout in linux is serious business.

What helped me was to enter shell alt+ctrl+f1 and close lightdm

sudo service lightdm stop

then

dpkg-reconfigure keyboard-configuration

and

sudo service keyboard-setup restart

I ran those commands as user and as root, then when I started lightdm

sudo service lightdm start

the keyboard was fixed.