incorrect spam setups cause spool messes on forwarders

Michael Lewinski mike at
Mon Dec 1 19:52:28 UTC 2003

On Dec 1, 2003, at 11:10 AM, Randy Bush wrote:

> is the following a general problem, or just one i am seeing?
> note 2821 says
>       450 Requested mail action not taken: mailbox unavailable
>          (e.g., mailbox busy)
>       550 Requested action not taken: mailbox unavailable
>          (e.g., mailbox not found, no access, or command rejected
>          for policy reasons)

FWIW, there are now fake smtp tarpits out there that behave this way 
(4xx deferrals of suspected spam).

The idea is to "punish" spammers by filling up their queues, although 
honestly I don't know of any spammers who actually *have* queues. They 
just borrow other people's of course. I'm not sold on the wisdom of 
this course.

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