preventing backscatter at the source

[Mark Nienberg]

The solutions discussed in the "backscatter problem" thread are all about preventing 
delivery of backscatter to our users.  Does anyone have information on preventing my 
mail server from generating backscatter in the first place?  I'd like to avoid 
sending bounce messages to innocent victims of address spoofing.

One thought I had was checking SPF records before sending a DSN, but I'm not sure if 
milter-SPF could do this as it is not the normal sequence.

The headers below that that google sends DSNs to addresses it knows are spoofed.  Can 
I do better?

Mark


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