Dynamically assign realm name when using DEFAULT realm

I am using FreeRADIUS Version 1.1.3, for host i686-redhat-linux-gnu I am trying to take the username of a format 'realm/username' and have FreeRADIUS take the 'realm' and pass it on in a sql query using %{Realm} and take the 'username' and pass it on with %{SQL-User-Name}. I have found I can do a DEFAULT realm, but the realm is passed on as DEFAULT instead of the name of the realm that was tried. Is there a better way to get the realm the user entered and pass it on in a SQL query? I have a SQL table with usernames and locations. When a user authenticates I want the username to match the username field only if the realm matches the location field in the database. Jer