Bug: Appointments+ / [app_services] insert weird things

As I have been evaluating more resource booking /appointment plugins I have installed (and later seemingly completely uninstalled) more plugins such as: http://wordpress.org/extend/plugins/easyreservations/

The problem now is that the [app_services] shortcode inserts a plain, non-processed shortcode on my appointment booking page: [easy_calendar resource="163" width="100" style="1" req="1" price="0"] which comes from this uninstalled plugin I mentioned above.