Ability for the end user to be able to clear his own messages from the mail queue

Right now, end users are able to clear their messages from the mail queue when their mailboxes are placed on "Hold" status. It would be great for them to be able to see and clear their personal mail queue anytime they want.

Weekly we see tickets from users who reached their deferred message limit due to issues with mails getting stuck in mail queue due to remote mailserver issues. We have to clear them ourselves, it would be great for the users to be able to perform this task themselves.