Ldap binding with different attribute

[LEONARDO FELL]

Hi everbody,
I have a freeradius+openldap working well, but I'd like to make some changes.
Below are the ldap module configuration:

                server = "ldap.mycompany.br"
                identity = "cn=Admin,dc=univates,dc=br"
                password = xxxxxx
                basedn = "dc=mycompany,dc=br"
                filter = "(uid=%{Stripped-User-Name:-%{User-Name}})"
                dictionary_mapping = ${raddbdir}/ldap_acad.attrmap
                ldap_connections_number = 5
                timeout = 4
                timelimit = 3
                net_timeout = 1

The users auth w/ a bind using the normal attrs (uid and password), but I think it'd better if  users ALSO could use another attrs like 'studentCode' to auth, instead of only uid/password.
Anyone know how to do that?
Cheers!

--
Leonardo Fell