The ungrab action (XF86Ungrab, bound to CTRL-ALT-KeyPad/ on my machine) plainly does not work. On the other hand, the clear ClearGrabs action works and kills the grabbing processes.
Version info: 1.12.3, but that choice does not appear in "Version" listbox on bugzilla.
Other people on the Interwebs seems to report the same problem: http://readlist.com/lists/suse.com/suse-linux-e/43/216030.html http://lists.freedesktop.org/archives/xorg/2012-March/054185.html
Created attachment 68309 [details] [review] fix (submitted to mailing list) Tested on top of Debian package 2:1.12.3-1, works for me.
Patch applied to Peter Hutterer's tree on 11 oct 2012: http://lists.x.org/archives/xorg-devel/2012-October/033960.html
commit c0a752d2864872023216005375a6a1973fadeffe Author: Lionel Elie Mamane <lionel@mamane.lu> Date: Tue Oct 9 03:17:49 2012 +0200 dix: fix Ungrab action #55785
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.