[Djigzo users] Quarantine recipients not previously registered

Hi, Im evaluating djigzo to act as an Encryption & DLP gateway and its looks like its just what I need to do that, however I need to have some sort of white list functionality that quarantines any emails to a recipient not set up within the system, thus allowing an administrator to add that address, generate certificate etc, can this be done within the DLP module or somewhere else?. This is a system that only sends out emails, but users via an application can add/modify recipient addresses without us knowing. Thanks Bruce