Remapping Emacs' Meta to Windows keys on Kubuntu

Remapping Emacs' Meta to Windows keys on Kubuntu

After quite a few hours of searching now, I still can't work out how to do
this.
Setup:
French Windows Comfort Curve Keyboard 2000 (which is why I want to remap)
HP Pavilion dm4 laptop running Kubuntu 12.04.
Emacs 24.3.1 cassou-emacs-precise
I simply want the ⊞ Win keys (+ left Alt if it's easier) to map to
the Ÿ Meta key in Emacs. I have tried everything I can think of - xev
tells me that the keys are mapped to META_L and META_R from KDE's point of
view - why on earth am I having so much trouble?
I've seen lots of stuff about remapping "mac-..." and "w32-..." stuff but
I'm running neither a Mac, nor Windows. Why is Alt no good for my Ÿ Meta?
Alt Gr (right Alt) is used for lots of letters on a French keyboard and
it's not practical to change that and I want a Ÿ Meta key on the right
side of the keyboard.
So I have done further research: Using Konsole and emacs -nw does not work
but if I change this either with KDE's keyboard management app or xmodmap
then it does work with Emacs in GUI mode.