Forum OpenACS Development: Retrieving Table Names To Which User 's Having Permissions

hi
i didnot get the answer to my requied question from the documentation, as i want to know if i create a table, how can i explicty decalre the permissions(the permissions shuld not be to the database users, it shuld be to the OpenACS users only) to that table, other wise i shuld create another table holding the permissions.
please reply
cheers
venu