Comment 4 for bug 618104

From the dmesg:
[231730.184798] debconf-communi[19153]: segfault at 7f206788 ip 03b3ba1d sp bf903390 error 6 in Gtk2.so[384e000+337000]

Could you please run a memory check ?
If it passes, could you please try to reinstall libgtk2-perl (sudo apt-get install --reinstall libgtk2-perl)

You can workaround your problem by selecting another frontend than gnome for debconf. To select another frontend, open a terminal and run:
$ sudo dpkg-reconfigure debconf
and select another entry than gnome (e.g dialog)