[fw-auth] Zend_Auth and Active Dircetory

Hello all,
I'm currently using Zend_Auth_Adapter_Ldap to authentication to our Active Directory server and I'm running into a strange predicament. I was able to get it to a point where I can successfully authenticate a user, but it sets the Zend_Auth identity to "domain/username", where I would like it to return only "username". So in my config I set "accountCanonicalForm" to 2, but then it fails authentication. The only settings I can set for successful authentication is "3" and "4", but then the identity is returned as "domain/user" or "user@domain". Any one know what I can do to return only "username"?

-Henry