gistfile1.sh

#!/bin/sh
set -e

### BEGIN INIT INFO
# Provides:  	postgresql
# Required-Start:	$local_fs $remote_fs $network $time
# Required-Stop:	$local_fs $remote_fs $network $time
# Should-Start:		$syslog
# Should-Stop:		$syslog
# Default-Start:	2 3 4 5
# Default-Stop:		0 1 6
# Short-Description:	PostgreSQL RDBMS server
### END INIT INFO

# Setting environment variables for the postmaster here does not work; please
# set them in /etc/postgresql/<version>/<cluster>/environment instead.

[ -r /usr/share/postgresql-common/init.d-functions ] || exit 0

. /usr/share/postgresql-common/init.d-functions

# versions can be specified explicitly
if [ -n "$2" ]; then
    versions="$2 $3 $4 $5 $6 $7 $8 $9"
else
    get_versions
fi

case "$1" in
    start|stop|restart|reload)
	if [ -z "`pg_lsclusters -h`" ]; then
	    log_warning_msg 'No PostgreSQL clusters exist; see "man pg_createcluster"'
	    exit 0
	fi
	for v in $versions; do
	    $1 $v
	done
        ;;
    status)
	LS=`pg_lsclusters -h`
	# no clusters -> unknown status
	[ -n "$LS" ] || exit 4
	echo "$LS" | awk 'BEGIN {rc=0} {if (match($4, "down")) rc=3; printf ("%s/%s (port %s): %s\n", $1, $2, $3, $4)}; END {exit rc}'
	;;
    force-reload)
	for v in $versions; do
	    reload $v
	done
        ;;
    *)
        echo "Usage: $0 {start|stop|restart|reload|force-reload|status} [version ..]"
        exit 1
        ;;
esac

exit 0

Confere se ele está marcado como executável, vai que…

Se tiver tu pode tentar remover:

update-rc.d -f postgresql remove

E adicionar novamente

update-rc.d postgresql defaults

Já fiz... nada =\