It looks like you've got a query with Oracle rather than Postgres syntax.
"acs_permission.permission_p" in Oracle sez "the permission_p package which is part of the acs_permission package".
Postgres doesn't have packages. What we've done is to map such functions into a form using double underbars, as in "acs_permission__permission_p"
(if the HTML rendering doesn't make it clear, the double underbar separates "acs_permission" and "permission_p")