Crashing to Log Screen/Greeter in certain actions

I'm with a fresh install of Lubuntu 14.04.2 LTS, three days ago, and for certain actions, the system crash and goes directly to the log screen/greeter to log again with my user and start again the session from the start.

Some of the actions i detected this behavior are:
- Pressing CTRL+ALT+SUPR.
- Pressing any Reload button in lxsession-default-apps.

I detected related information in dmesg, these are from two different crashes:

[ 89.935474] lxsession[1482]: segfault at 0 ip 080509b8 sp bfd69f40 error 4 in lxsession[8048000+34000]
[ 356.794763] lxsession[1988]: segfault at 0 ip 080509b8 sp bf98b4c0 error 4 in lxsession[8048000+34000]

--------

$ lsb_release -rd
Description: Ubuntu 14.04.2 LTS
Release: 14.04

$ apt-cache policy lxsession
lxsession:
  Instalados: 0.4.9.2+git20140410-0ubuntu1.2
  Candidato: 0.4.9.2+git20140410-0ubuntu1.2
  Tabla de versión:
 *** 0.4.9.2+git20140410-0ubuntu1.2 0
        500 http://es.archive.ubuntu.com/ubuntu/ trusty-updates/universe i386 Packages
        100 /var/lib/dpkg/status
     0.4.9.2+git20140410-0ubuntu1 0
        500 http://es.archive.ubuntu.com/ubuntu/ trusty/universe i386 Packages

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: lxsession 0.4.9.2+git20140410-0ubuntu1.2
ProcVersionSignature: Ubuntu 3.16.0-33.44~14.04.1-generic 3.16.7-ckt7
Uname: Linux 3.16.0-33-generic i686
ApportVersion: 2.14.1-0ubuntu3.8
Architecture: i386
CurrentDesktop: LXDE
Date: Fri Apr 3 13:59:22 2015
InstallationDate: Installed on 2015-03-31 (2 days ago)
InstallationMedia: Lubuntu 14.04.2 LTS "Trusty Tahr" - Release i386 (20150218.1)
ProcEnviron:
 LANGUAGE=es_ES
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=es_ES.UTF-8
 SHELL=/bin/bash
SourcePackage: lxsession
UpgradeStatus: No upgrade log present (probably fresh install)