I haven't done this myself, but I know others have. You should make sure your PostgreSQL server is running on a TCP/IP socket by providing the "-i" option to postmaster at start time. Then, your connect string in your AOLserver .tcl initialization file should specificy the IP, the port, and the username and password for logging into Postgres.
Thus, your main issue is making sure that you have Postgres correctly running in username/password authentication mode.
I know someone out there has done this and can add more details?
