We have the same issue in 2.5.1+ (Build: 20130802) - emails work fine for when a student submits, but when we give a feedback file, it doesn't email the student notification its there. Previous versions we had no issues.
Did you ever get it solved?
In reply to Harrie Phillips
Re: Feedback email notification not being sent Moodle 2.5
by Pawel Wojnicki -
Any luck with this? I have the same problem ...