Report non-existing mail addresses during password reset

When a user makes use of the “password reset” dialog he might enter a slightly wrong mail address. Despite the fact, that no user with the entered mail address exists, he is prompted with the info message “You should receive an email shortly with further instructions.”. This is pretty wrong considering that no mail will be sent. The error is logged as an event but the user gets no notification.

I understand that this prevents attackers from guessing registered emails; but isn’t this possible using the registration feature with email field anyway?

Is there an easy way to present a message when a user enteres an unknown mail adress?

Many thanks in advance,
Dominik

You could certainly implement a custom Authenticator to do this, but, as you guess, the choice is to prevent attackers harvesting emails.