Forum OpenACS Q&A: Re: Aolserver 4.0 with Postgres 7.2 , invalid command name "ns_db"

The most interesting part of your config file is missing ;).

If you want to use AOLserver4 you need to add "ns_param nsdb ${bindir}/nsdb.so" to your modules section. In the config file it should actually say something like "you need this for AOLserver4".