To provide user feedback if a user's account or password is expired, use:
 

::LDAP
BindUser CN=ezproxy,CN=users,DC=yourlib,DC=org
BindPassword verysecret
URL ldap://ldapserv.yourlib.org/CN=users,DC=yourlib,DC=org?sAMAccountName?sub?(objectClass=person)
Expired; Deny expired.htm
/LDAP