Comment 29 for bug 1295521

Ok, this definitely shows that common-session is broken after installing libpam-systemd:i386. This confirms what you've said, but is really quite bizarre since there is nothing in the libpam-systemd maintainer scripts which should cause this.

Can you please also attach /var/log/dpkg.log and /var/log/apt/term.log from your system, so we can see what the package manager has to say about what was happening when you installed/removed these packages? (Ideally only /var/log/apt/term.log is needed, but I don't know if you were using apt to manage these packages or if you used dpkg directly)