Comment 21 for bug 549217

Michael and I have now refined the test case to make it easier to run:
1. Install Ubuntu.
2. Log in to the new Ubuntu installation for the first time.
3. In “Software Sources” > “Updates”, choose “Check for updates: Daily” and “Install security updates without confirmation”.
4. At a terminal, run sudo /etc/cron.daily to trigger the background installation of security updates.
5. Once cron.daily has exited, run killall update-notifier && NO_FAKE_STAT=1 faketime -f +1d update-notifier to test the update-notifier behavior. Update Manager should open, displaying only non-security updates.

If this works, but the steps in the current description still do not, then I guess the problem is with step 4: /etc/cron.daily isn't being run, or the updates are failing when being run from cron.