chromium (and chrome) won't start in guest session

[Alan Pope 🍺🐧🐱 🦄]

guest-WLS9SG@wopr:~$ chromium-browser
Failed to move to new PID namespace: Operation not permitted

guest-WLS9SG@wopr:~$ ps aux | grep chromium
122 17398 0.0 0.1 250236 15272 pts/3 S+ 10:20 0:00 /usr/lib/chromium-browser/chromium-browser
122 17400 0.0 0.0 250976 5912 pts/3 S+ 10:20 0:00 /usr/lib/chromium-browser/chromium-browser
122 17475 0.0 0.0 9384 928 pts/4 S+ 10:20 0:00 grep --color=auto chromium

Chromium won't start in a guest session, neither will chrome. Perhaps we're missing an apparmor profile?

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: chromium-browser 20.0.1132.47~r144678-0ubuntu6
ProcVersionSignature: Ubuntu 3.5.0-16.24-generic 3.5.4
Uname: Linux 3.5.0-16-generic x86_64
ApportVersion: 2.5.2-0ubuntu4
Architecture: amd64
ChromiumPrefs: can't open profile /tmp/guest-WLS9SG/.config/chromium/Default/Preferences
Date: Mon Oct 1 10:21:56 2012
Desktop-Session:
 DESKTOP_SESSION = ubuntu
 XDG_CONFIG_DIRS = /etc/xdg/xdg-ubuntu:/etc/xdg
 XDG_DATA_DIRS = /usr/share/ubuntu:/usr/share/gnome:/usr/local/share/:/usr/share/
Env:
 MOZ_PLUGIN_PATH = None
 LD_LIBRARY_PATH = None
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha amd64 (20120102)
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: chromium-browser
UpgradeStatus: No upgrade log present (probably fresh install)
chromium-default: CHROMIUM_FLAGS=""
gconf-keys: /desktop/gnome/applications/browser/exec = b'firefox\n'/desktop/gnome/url-handlers/https/command = b'sensible-browser %s\n'/desktop/gnome/url-handlers/https/enabled = b'true\n'/desktop/gnome/url-handlers/http/command = b'sensible-browser %s\n'/desktop/gnome/url-handlers/http/enabled = b'true\n'/desktop/gnome/session/required_components/windowmanager = b''/apps/metacity/general/compositing_manager = b''/desktop/gnome/interface/icon_theme = b'ubuntu-mono-dark\n'/desktop/gnome/interface/gtk_theme = b'Ambiance\n'

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.