some guys do the good thing
After being busy a year with indexing hacked-defaced Belgian sites and noticing that some just get hacked over and over again or just didn't care for months, I must say that I am relieved and quite happy because I have noticed that some important mailservers in Belgium have started closing themselves down since last week and I sincerely thank you for that.
Rule of three
* refuse all bad mail addresses from the world
* accept only mail-senders to the world from a defined range and domain
* control, monitor, log and adjust permanently
And please participate at the http://www.projecthoneypot.org