[exim] can the exim4 use win2000 AD server for ldap auth?

      I want use the win2000 ADS for exim4 ldap server do SASL auth,
win2000 AD can do it? use openldap for this I think is easy,but our
need 2000 ADS for user login auth.so I want use win2000
ad do ldap server,if I add new schema in win2000 AD,it's no
problem,but I only want use the default schema in win2000 ADS. how can
do this?