Emacs with both Meta AND Alt not working

[Ronan KERYELL <Ronan.Keryell@lit.enstb.org>]

I use xfree86 and emacs21 from sid and eventually after a dist-upgrade the
Emacs behavior around the Meta and Alt keys changes.

I want the Meta_L on the left windows key and Alt_L on the Alt_L.

I have a /etc/X11/Xmodmap that I update according to the new xfree86
version after each new versions to have this behavior.

But on the last version I cannot have this working. :-(

I've also used a XF86Config-4 with a simple :
Section "InputDevice"
	Identifier  "Keyboard0"
	Driver      "keyboard"
        Option      "CoreKeyboard"
	Option "XkbRules" "xfree86"
	Option "XkbModel" "pc104"
	Option "XkbLayout" "us"
    #altwin:left_meta_win	Meta is mapped to the left Win-key.
	Option "XKbOptions" "altwin:left_meta_win"
EndSection
and Emacs reports for example Win_L-q and Alt_L-q respectively as :
H-s-q
M-q

and xmodmap returns :
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),  BadKey (0x7d),  BadKey (0x9c)
mod2        Num_Lock (0x4d)
mod3
mod4        BadKey (0x7f),  BadKey (0x80)
mod5        Mode_switch (0x5d),  ISO_Level3_Shift (0x7c)
that is clearly a mess with all this BadKey... :-(
Modifying it with xmodmap appears just to increase the mess...
xmodmap -e 'clear mod4'
produce a correct :
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),  BadKey (0x7d),  BadKey (0x9c)
mod2        Num_Lock (0x4d)
mod3
mod4
mod5        Mode_switch (0x5d),  ISO_Level3_Shift (0x7c)

but then with a :
xmodmap -e 'add mod4 = Meta_L'
the mess is back :
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),  BadKey (0x7d),  BadKey (0x9c)
mod2        Num_Lock (0x4d)
mod3
mod4        Alt_L (0x40),  BadKey (0x9c)
mod5        Mode_switch (0x5d),  ISO_Level3_Shift (0x7c)


It seems to be even more complex than what is discussed in
http://lists.gnu.org/archive/html/help-gnu-emacs/2004-06/msg00195.html or in bug 
#255286255286

Sounds like an issue rather on the X11 part around the modifier stuffs and
the conservative assumption of Emacs that if there is no key with a plain
Meta modifier Emacs decides to use Alt keys as Meta...

Does anyone have this kind of stuff working ?

Thank you,
-- 
  Ronan KERYELL               |\/  Tel:    (+33|0) 2.29.00.14.15
  Labo Informatique & Télécom |/)  Fax:    (+33|0) 2.29.00.12.82
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