post_install() {
  if [ ! "`/bin/grep /bin/zsh /etc/shells`" ]; then
    /bin/sed -i "s|/bin/bash|/bin/bash\n/bin/zsh|" /etc/shells
  fi
}

post_upgrade() {
  post_install $1
}

pre_remove() {
  /bin/sed -i '/^\/bin\/zsh/d' /etc/shells
}

# vim:set ts=2 sw=2 et: