fight spam problem: sender equal to receiver

[Roland Plüss]

I've got since a couple of weeks a rather nasty spam increase ( in fact 
massive ). Some jerk sends forged emails to some address [EMAIL PROTECTED] on my 
server with the same email address as the receiver ( hence [EMAIL PROTECTED] 
receives an email from [EMAIL PROTECTED] ). It's clearly not relayed by my server 
since the emails come from some spurious servers but got the sender 
email forged.

Now I could not figure out a way with postfix-2.5.5 to reject emails 
where the sender and receiver emails do match. Any ideas how to 
accomplish this?

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Yours sincerely
Plüss Roland