Release 1.0 - ...
<notProcessed> element
The "Unprocessed Category" special source will accept events which contains at least one category that doesn't have a corresponding category source defined in configuration elsewhere.
In this example these events will be ignored, since there are no listeners configured within the notProcessed element.
The check whether a category source is configured includes the special source "All Events". If this source is configured the special source "Unprocessed Category" has no effect.