Logging in with Shibboleth doesn't fire the "User Login" Event?

In my installation the users login with Shibboleth [1], but the rule [2] I've set up to be executed on "User has logged in" event, isn't executed.

On the other hand, when I login as administrator through the normal Drupal way, the rule is executed.

Does this mean that the external login event isn't handled at all?

Is there a way to overcome this?

[1] http://drupal.org/project/shib_auth
[2] http://drupal.org/project/rules