Here's a first attempt at a patch to fix the problem. Also posted on upstream bug.
** Attachment added: "Patch to fix problem" http://librarian.launchpad.net/5722339/user-settings.diff -- [users-admin] Changing UID needs notice to reboot https://launchpad.net/bugs/78527 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
