FreeRADIUS and LDAP

Hi all, Our setup in LDAP right now is: ou=People,dc=domain,dc=net Under the Organizational Unit of "People", we have our posixAccount users, which have valid UNIX uid's and have email accounts. However, not all of our Email users (ou=People) have radius accounts as well, and sometimes, user "bob" in Email is not the same user as user "Bob" in radius. Therefore, I'm thinking of just creating ou=Radius, and then putting our dial up customers in there. If I were to do that, is there a better schema I can use other than posixAccounts? Such as a radius-only schema that supports radius parameters as well? Thanks! -Matt