Keystone auth needs a way to propogate some error message based on some kind of configuration

We are using a password policy in ldap that locks accounts if they try authenticating with a wrong password more than certain number of times.

When an account is locked, the Horizon UI shows Invalid username/password.

Following is the change i made to get what I wanted, but we need something more generic and configurable (example easily allow user to know his password has expired, based on the response coming from the keystone client)

vim "/usr/lib/python2.6/site-packages/openstack_auth/backend.py" - changes on line 98 and 99

 94 except (keystone_exceptions.Unauthorized,
 95 keystone_exceptions.Forbidden,
 96 keystone_exceptions.NotFound) as exc:
 97 msg = _('Invalid user name or password.')
 98 if exc.message == "Error, Account is locked":
 99 msg = "Error, Account is locked contact the administrator"