tcpip_socket vs -i

I'm trying to find out the true behavior of postgres in regards to accepting
tcpip socket connections. According to the documentation, I should be able
to start postmaster with just "pg_ctl start" then specify tcpip_socket = on
(or possibly tcpip_socket = true, I tried both) in postgresql.conf and have
tcp_ip socket connections working, however after a multitude of different
attempts I found no way to get tcpip sockets to work unless I started the
postmaster with -i. I understand that the command line options would
override the conf file in cases of conflict, but does the mere omission
of -i override any attempts to use sockets otherwise? I would hope that not
specifying -i would allow me to turn socket connections on and off via the
conf file, without a restart of the database, but what is happening in
practice seems to be going against what is in the docs. Anyone know for
sure?

Robert Treat
Auction Management Solutions, Inc.
Tampa, FL