How do I disable: Adding missing FROM-clause

I know that PSQL has the cool feature of doing: Adding missing FROM-clause

But I want to disable it, because its silent adding can allow a bad SQL statement to execute a
cartesian select (when in fact it should error out).

I searched and found references to changing the postgresql.conf with:
add_missing_from = false
enable_implicited_join = false

But neither one of these seems to disable the functionality (I did a reload after making the change)

Do I have to completely stop the db to make the change?  Or is there something else I should be
doing to disable it?

Thanks

Terry Fielder
Manager Software Development and Deployment
Great Gulf Homes / Ashton Woods Homes
terry@greatgulfhomes.com
Fax: (416) 441-9085