I'm running PostgreSQL 8.1.3.  In my postgresql.conf, the following  
works:
    listen_addresses = '*'
but the following does not:
    listen_addresses = '192.168.1.33'
I get an error:
    WARNING:  could not create listen socket for "192.168.1.33"
    FATAL:  could not create any TCP/IP sockets
I'm running Mac OS X 10.4.6 on PPC, if that makes a difference.
For now, listen_addresses = '*' works for me, but I was curious why I  
couldn't use the more restrictive listen_addresses.
Geoffrey
--
Geoffrey S. Knauth | http://knauth.org/gsk