Syntax in postgresql.conf

A comment in postgresql.conf on Debian says:

"
          # comma-separated list of addresses;
          # defaults to 'localhost', '*' = all
"
But when I try

listen_addresses = '192.168.0.1', 'localhost'

I get

$sudo /etc/init.d/postgresql-8.1 restart
 * Restarting PostgreSQL 8.1 database server
 * Error: Invalid line 53 in /etc/postgresql/8.1/main/postgresql.conf

 Why?

 Regards
 Johann
--
Johann Spies          Telefoon: 021-808 4036
Informasietegnologie, Universiteit van Stellenbosch

     "Wait on the LORD; be of good courage, and he shall
      strengthen thine heart; wait, I say, on the LORD."
                                    Psalms 27:14