Distribution/Version: XP SP 2

Currently the Wintab code in the Win32 GDK backend doesn't manage context
overlap order other than doing a WTOverlap(context, TRUE) at initialization.
This doesn't follow the Wintab specifications, although at least the Wacom
drivers are supposed to manage the context overlap order themselves
(http://www.wacomeng.com/devsupport/ibmpc/wacomwindevfaq.html#FAQ1.7).

Sometimes when I start testinput the tablet is initialized correctly, but no or
only a few tablets events are received. If I add a button that calls WTOverlap
and click it, I start getting tablet events. Strangely enough the problem
doesn't seem to happen for me with GIMP anymore, it did a few times before.
There have also been a few reports on the gimpwin-users Yahoo group of similar
problems in GIMP.

The easiest way for me to reproduce the problem is to execute 

for f in `seq 1 100`; do ./testinput --gdk-debug=input; sleep 1; done

and scribble a little and close and restart testinput until the problem occurs.
I'll attach a (too?) simple patch that seems to fix the problem for me.

(Wacom Graphire 3 tablet, using the 4.84-6 drivers, and latest gtk-2-6 from
anoncvs on Windows XP SP2)