далее ситуация как описана выше
при нажатии на экран:
"при прикосновении к экрану сессия завершается и выбрасывает экран выбора пользователя"
версия LUBUNTU 2.11

X.Org X Server 1.11.3
Release Date: 2011-12-16
X Protocol Version 11, Revision 0
Build Operating System: Linux 2.6.38-1209-omap4 armv7l Linaro
Current Operating System: Linux linaro-server 3.10.17 #3 SMP PREEMPT Mon Mar 21 12:45:40 MSK 2016 armv7l
Kernel command line: console=ttymxc0,115200 root=/dev/mmcblk0p1 rootwait rw video=mxcfb0:dev=ldb,LDB-XGA,if=RGB24 video=mxcfb1:dev=hdmi,1280x720M@60,if=RGB24 consoleblank=0
Build Date: 05 October 2012 09:10:36AM
xorg-server 2:1.11.4-0ubuntu10.8+ti1.1 (For technical support please see http://www.ubuntu.com/support)
Current version of pixman: 0.24.4
Before reporting problems, check http://wiki.x.org
to make sure that you have the latest version.
Markers: (--) probed, (**) from config file, (==) default setting,
(++) from command line, (!!) notice, (II) informational,
(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/Xorg.0.log", Time: Thu Jan 1 00:00:27 1970
(==) Using system config directory "/usr/share/X11/xorg.conf.d"
xf86TslibControlProc
xf86TslibControlProc
/usr/bin/X: symbol lookup error: /usr/lib/xorg/modules/input/tslib_drv.so: undefined symbol: xf86XInputSetScreen
** Message: find greeter (nil)

** Message: find idle 0x19f8750

** Message: add 0x19f8750

** Message: prepare greeter on :0

** Message: start greeter on :0

** Message: xserver stop, restart. return status 7f00


(lxdm-greeter-gtk:921): Gtk-WARNING **: cannot open display: :0
** Message: add xserver watch


X.Org X Server 1.11.3
Release Date: 2011-12-16

в Xorg ничего подозрительного не обнаружил
зато в LXDM.LOG
/usr/bin/X: symbol lookup error: /usr/lib/xorg/modules/input/tslib_drv.so: undefined symbol: xf86XInputSetScreen