You tell me it's mostly for the French because only they who uses the azerty, and... you're right
Ok, remember that you must to be root !
And now, let's go !
firstly, download the file azerty_keymap.zip (below) and chose between these 2 methods.
the first : Using ADB (you have to download Android SDK before)
just plug your Xoom and push files with these command lines
adb push Generic.kl /system/usr/keylayout/Generic.kl
adb push Generic.kcm /system/usr/keychars/Generic.kcm
the second method : Using Root Explorer (or anything else like it)
copy Generic.kl in the folder /system/usr/keylayout/ (mount r/w before)
then copy Generic.kcm in the folder /system/usr/keychars/
and NOW...!!!! Enjoy your azerty keyboard with.
I hope it will help you.