Are you basically looking for some sort of web based solution that will allow your users to punch their AD username and password into a website and then be able to reset their password? If so it can be done through LDAP via SSL, can be a bit fiddly as you need to have your server setup to generate CA certificates but the actual website / page itself shouldn't be too difficult to script, I do have some LDAP PHP scripts somewhere so I will have a look and see if I can get a simple login and reset your password utility up and running.
