problem between xfwm4 and keymap

[Olivier Fourdan]

Yves-Alexis Perez wrote:
> Maybe the problem is in the keymap, but I don't know how to fix this..

What does "xmodmap" returns?

Does the Alt key is listed as a modifiers, for example as follow:

xmodmap
xmodmap:  up to 3 keys per modifier, (keycodes in parentheses):

shift       Shift_L (0x32),  Shift_R (0x3e)
lock        Caps_Lock (0x42)
control     Control_L (0x25),  Control_R (0x6d)
mod1        Alt_L (0x40),  Alt_L (0x7d),  Meta_L (0x9c)
mod2        Num_Lock (0x4d)
mod3
mod4        Super_L (0x7f),  Hyper_L (0x80)
mod5        Mode_switch (0x5d),  ISO_Level3_Shift (0x7c)

Cheers,
Olivier.