post_upgrade() {
  if (( $(vercmp $2 2.013-1) <= 0)); then
    sed -i -e 's/white/welcome/g' -e 's/black/block/g' etc/webmin/spam/* || true
cat << _EOF

>>> Webmin's SpamAssassin (spam) module has been patched for SpamAssassin v4+.
>>> Replaced white/black with welcome/block in /etc/webmin/spam/*
>>> Please verify the same and rename any files if necessary.

>>> Also do not forget to activate version compatibility:
>>>   enable_compat welcomelist_blocklist

>>> For details, see:
>>>   https://cwiki.apache.org/confluence/display/spamassassin/WelcomelistBlocklist

_EOF
  fi
}