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[Steve Freegard]

Alex Broens wrote:
>> At the end of the day - it's all about trust.
> 
> + not all senders treat a 450 as such.
> 
> There an $unknown_count of weird apps out there which don't requeue and
> will silently drop a msg after a temp fail.

Such hosts aren't worth bothering about as they are terminally broken
and are a tiny percentage of messages that might hit someone's MX.

Temporary failures are a fundamental principal of SMTP dating back to
the original RFC.  Such failures should not be tolerated by anyone.

Regards,
Steve.