postinstall script and debconf configuration

[Matthijs Mohlmann <matthijs@cacholong.nl>]

On somehow i can't get this to work. And i don't know why it won't work:

#! /bin/sh
set -e
. /usr/share/debconf/confmodule
PDNSCONF=/etc/powerdns/pdns.conf
config () {
  # pdns/masterslave = string
  db_get pdns/masterslave
  MASTER=$RET
  # pdns/lazy_recursion = boolean
  db_get pdns/lazy_recursion || RET="true"
  LAZY=$RET
  # pdns/localaddress = string
  db_get pdns/localaddress
  ADDR=$RET
  # pdns/autostart = boolean
  db_get pdns/autostart || RET="false"
  START=$RET
  # pdns/chroot = boolean
  db_get pdns/chroot || RET="false"
  CHROOT=$RET
  # pdns/axfr = boolean
  db_get pdns/axfr || RET="false"
  AXFR=$RET
  # pdns/localport = string
  db_get pdns/localport
  PORT=$RET
}

case "$1" in
  configure)
    if [ "$2" = "" ]; then
      if [ -f $PDNSCONF ]; then
        cp $PDNSCONF $PDNSCONF.backup
      fi
      if [ "$MASTER" != "nothing" ]; then
        echo master;
        sed -i -e "s/^\(#\)\?\(# \)\?$MASTER=$/$MASTER=yes/" $PDNSCONF
      fi
      if [ "$LAZY" = "true" ]; then
        echo lazy
        sed -i -e "s/^\(#\)\?\(# \)\?lazy-recursion=
$/lazy-recursion=yes/" $PDNSCONF
      fi
      if [ ! -z $ADDR ]; then
        echo localaddress
        sed -i -e "s/^\(#\)\?\(# \)\?local-address=$/local-address=
$ADDR/" $PDNSCONF
      fi
      if [ "$CHROOT" = "false" ]; then
        echo falsechroot
        sed -i -e "s/^chroot=/# chroot=/" $PDNSCONF
      fi
      if [ "$AXFR" = "true" ]; then
        echo axfr
        sed -i -e "s/^disable-axfr=.*$/disable-axfr=no/" $PDNSCONF
      fi
      if [ ! -z $PORT ]; then
        if [ $PORT -ne 53 ]; then
          echo port
          sed -i -e "s/^\(#\)?\(# \)?local-port=$/local-port=$PORT/"
$PDNSCONF
        fi
      fi
      if [ db_get pdns/autostart ]; then
        echo start
        sed -i -e "s/^START=.*$/START=\"yes\"/" /etc/default/pdns
      fi
    fi
  ;;

  abort-upgrade|abort-remove|abort-deconfigure)

  ;;

  *)
    echo "postinst called with unknown argument \`$1'" >&2
    exit 1
  ;;
esac

exit 0

If someone can point me out what i'm doing wrong ? The checks are always
true or always false. I think i do something wrong in the db_get
commands but i don't know what.