Somehow, a topic posted by a user was 'announced' (via private Email) to every user that has ever registered here.
It's entirely my fault that this feature was even available and I apologize to those who have been inconvenienced by it.
That feature has now been permanently disabled even for the administrator.)
This was only caused by my own incompetence, and not a spammer, hacker,... etc.
It was an annoyance but not a breach in security.
No email addresses were revealed or made visable to guest or unregistered users.