Since Domino 10 already have some new mail send policy feature (limit number of attachment, size of attachment and number of recipient) when user click the send button, please extend this to also include the ability to cc / bcc additional address based on condition or display additional warning based on certain condition. Sample use cases are as follow :
1. User's manager need to be informed for any email to external parties.
2. Need to implement something similar to journaling for email meeting certain condition but user other than admin need to open the NSF so Journaling cannot be done since it is encrypted using the admin ID.
3. Warning that user are sending email to external parties.