Attached Documents's Security

The security of the documents that we attach to the activities is a topic on which companies like mine pay more and more attention. I propose the modification of the feature that allows users to insert new activities via email so that the text of the email can become a PDF attachment (not to be included in the clear description of the activity since it could contain sensitive informations) and the possibility to encrypt automatically all attachments that are manually or automatically added. The system must protect against malicious persons who could download those attachments and make an unauthorized use by our company.