The problem has definitely not gone away - even if I hoped so.  On August 8th, I took my 4th dedicated email address (belonging to my own domain) since April. Just a few minutes ago first spams arrived :((

While it is possibly to 'wash' the emails with external programs that is certainly not ideal. I get dozens of emails related to my merchandise among dozens of spam emails every day, and sometimes in a hurry a few important ones gets deleted as well. 

Only Renderosity knows about this email (and the other 3). They have never been used for any other purpose.