post_upgrade() {
  [[ $(vercmp "$1" 1:1) -le 0 ]] && return 0
  cat << EOF
* Since v1.0, lxc-shutdown(1) is gone and its functionality is provided by
* lxc-stop(1) by default. The old lxc-stop(1) behavior can be recovered
* with 'lxc-stop --kill'.
EOF
}