Bug#593087: xinput buttons not recognized correctly

[gator_ml at yahoo.de]

Package: libgtk2.0-0
Version: 2.20.1


In recent gtk2 versions, xinput button events (in my case from a wacom
tablet, other devices probably as well) do not work correctly any
more. Normal GUI usage is ok, only programs that actually handle
"extended input devices" (gimp/inkscape) are affected: Button events
on the canvas are only recognized, if 2 buttons are down at the same
time.

With a 2-button stylus for example, drawing (button 1, normally just
by touching the tablet with the stylus) only works, if another button
is pressed before the button hits the tablet. The other way around,
normally the context menu is accessed by pressing button 3 (the rear
of the rocker switch) without touching the tablet; this now only works
if I 1st push the stylus on the tablet and then press the button.

It is evident, that the problem lies within gtk2; on my base system
(libgtk2.0-0 version 2.12.12-1~lenny2) the input buttons work as
expected in inkscape and gimp. I 1st ran into this problem after
having installed gtk 2.18 from backports.org, after downgrading back
to 2.12 things work normal again. The same problem also occurs when
running from a freshly installed squeeze in a chroot environment.