it is true and besides the german legal letter below you violate a second law at the same time - that is why you have to run a spamfilter *before queue* and sa-milter exists - in case you reject a message the sending server is responsible for a bounce
in case you accept and silently drop it you have a unacceptable configuration - independent of laws - in case of a important and time critical mail i need to know it was rejected and so can call the person by phone or try to >remove something which triggered a false positive
there are two important rules for mail:
a) if you accept it you have to deliver it b) if you can't deliver it you must not accept it
if you follow b) you don't become a backscatter
Yep, that's correct about point b). Plus, I also personally agree that rejecting is better, than having it silently discarded. Good thing is that I do not reside in Germany so I am safe on that
In fact, postfix before-queue content filter has limits in the amount of mail that a site can handle: http://www.postfix.org/SMTPD_PROXY_README.html therefore legal part of this in Germany limits all German people on resources as every single person is forced to run before-queue filters which in my opinion has its own disadvantages on top of everything else and despite the laws as well.
