Request Rejection Notification

We currently have our SD+ environment setup to allow requesters to open tickets via an Email, however its configured to ignore emails that are not registered in SD+. This has been absolutely awesome for both weeding out spam and also only processing requests that are authorized to open tickets.

However, from time to time we'll have someone submit an email and although they are not an approve requester in SD+ and their email essentially vanishes into the bit-bucket, I think it would be nice if ignored emails would send a notification back the original sender notifying them that their email is not being processed or has been rejected. They atleast know that we're not blowing them off and they need to take some other type of action (like request an account from their account management, etc...). Is it possible to set this up?