session-installer crashed with ImportError in /usr/lib/python2.7/dist-packages/sessioninstaller/core.py: No module named xdg.DesktopEntry

it just died

ProblemType: Crash
DistroRelease: Ubuntu 13.04
Package: sessioninstaller 0.20+bzr134-0ubuntu6
ProcVersionSignature: Ubuntu 3.8.0-31.46-generic 3.8.13.8
Uname: Linux 3.8.0-31-generic x86_64
ApportVersion: 2.9.2-0ubuntu8.4
Architecture: amd64
Date: Fri Sep 13 16:39:48 2013
ExecutablePath: /usr/bin/session-installer
InstallationDate: Installed on 2013-07-29 (45 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
InterpreterPath: /usr/bin/python2.7
MarkForUpload: True
PackageArchitecture: all
ProcCmdline: /usr/bin/python /usr/bin/session-installer
ProcEnviron:
 SHELL=/bin/bash
 XDG_RUNTIME_DIR=<set>
 PATH=(custom, user)
 LANG=de_DE.UTF-8
PythonArgs: ['/usr/bin/session-installer']
SourcePackage: sessioninstaller
Title: session-installer crashed with ImportError in /usr/lib/python2.7/dist-packages/sessioninstaller/core.py: No module named xdg.DesktopEntry
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip fuse libvirtd lpadmin plugdev sambashare sudo