incorrect spam setups cause spool messes on forwarders

Steven M. Bellovin smb at
Mon Dec 1 19:42:50 UTC 2003

In message <10021859.1070281409 at>, Michael Loft
is writes:
>I personally haven't seen ANY validation, just an arbitrary block that's 
>been in place for over a month without cause, reason, or even any ability 
>to contact them. 

Right.  Assuming that the described validation scheme is, in fact, 
what's being used, you'd expect Verizon's mailer to retain and cache 
the validation.  That way, a single 450 can be turned into a 200 series
or a 550.

As Randy said, 450 means "there's a problem here that should be fixed 
soon; come back later".  If it doesn't change, it's not a 450.

		--Steve Bellovin,

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