Multiple back-end authentication services

[Eduardo Ito]

I have a situation where before doing the real authentication, I need
to lookup the username in a table to decide if it will be
authenticated against Active Directory or a data base.

How can I implement this with CAS?

-- 
Eduardo Issao Ito
Summa Technologies

"The structure of a system tends to mirror the structure of the group
producing it."
[Mel Conway - April, 1968 Datamation]