To allow TCPIP connections to postgresql you need to insert "-i" in the startup script. I am using RH7 and have tried placing "-i" in a number of spots in the startup (postgresql) script files but nothing seems to work.
I am keen to connect to postgresql from a windows workstation using ODBC.

On about line 167 or so of /etc/rc.d/init.d/postgresql start up script it reads (approximately):

su -l postgres -s /bin/sh -c "/usr/bin/pg_ctl -D $PGDATA -p /usr/bin/postmaster -o '-p ${PGPORT}' start > /dev/null 2>&1" < /dev/null

I think you can add the "-i" in the following position:

su -l postgres -s /bin/sh -c "/usr/bin/pg_ctl -D $PGDATA -p /usr/bin/postmaster -o '-p ${PGPORT} -i' start > /dev/null 2>&1" < /dev/null

The -o option passes paramters directly to the underlying postmaster. These options that are passable by the -o include the -i intranet connection option.

Good luck