I'm an happy user of the linuxwacom driver since years, I have to thank you for that first !
Recently, I set up my Cintiq 21UX tablet (old model) with the new Gnome 3.10 expresskey interface, and I'm not sure if it's linked, but now each time I use the left pad (not the strip), it causes an X.org crash (my session crash and I'm back to GDM login).
For some button (bottom one) a single "click" is enough, for some other (top ones) a "long click" cause the crash.
Using the right pad or the touch stripes, everything works just fine.
My distribution is Manjaro 8.8 stable with a 3.10 kernel, with latest xorg server (1.14.5-1), latest open ati driver (xf86-video-ati 1:7.2.0-1) and latest wacom driver (libwacom 0.8-1 and xf86-input-wacom 0.23.0-1).
I'm not sure wich log files I should join to this bug report, so here is my Xorg log... Don't hesitate to ask me more.
And because it's a special day today, I wish you a merry christmas !