If a user writes a comment and check the box their emailadress will show up in the subscribers list, so that works. But the link for a manual subscription leads to a 404 page not found. Both http://www.inflection.nl/manage-subscriptions and http://www.inflection.nl/comment-subscriptions do not seem to exist and return that error. The virtual management page is enabled in the settings.
I'm using the latest versions of both WordPress and the plugin.