Found with the help of calibre-debug this:
kfmclient: symbol lookup error: /usr/lib/libQtDBus.so.4: undefined symbol: _ZN14QObjectPrivate15checkWindowRoleEv
This Module is part of the package libqt4-dbus:
libqt4-dbus:
Installiert: 4.4.3-0ubuntu1.2
Kandidat: 4.4.3-0ubuntu1.2
Versions-Tabelle:
*** 4.4.3-0ubuntu1.2 0
500
http://de.archive.ubuntu.com intrepid-updates/main Packages
100 /var/lib/dpkg/status
4.4.3-0ubuntu1 0
500
http://de.archive.ubuntu.com intrepid/main Packages
Sorry, I think, I'm in the wrong forum..