Comment 6 for bug 430224

Text added at <>:

Upstart jobs cannot be started in a chroot because upstart acts as a service supervisor, and processes within the chroot are unable to communicate with the upstart running outside of the chroot (Bug:430224). This will cause some packages that have been converted to use upstart jobs instead of init scripts to fail to upgrade within a chroot. Users are advised to configure their chroots with /sbin/initctl pointing to /bin/true, with the following commands run within the chroot:

dpkg-divert --local --rename --add /sbin/initctl
ln -s /bin/true /sbin/initctl