Re: [exim] Heads up?

Marilyn Davis wrote:
>>
>>>But then, can't we use bounce_message_file to customize the message
>>>so that it is as friendly as a regular challenge?
>>
>>No, because if you're responding with a 5xx to reject the message, you
>>don't generate any bounce; the _only_ text you get to specify is in the
>>5xx reason string. If a bounce is generated, it will be generated by
>>the originating MTA.

Just to follow up on this, I've been experimenting with my own spam
rejection system today, and discovered that at least Exchange severely
limits the size of the text it will display in a bounce caused by a 550:

> The following recipient(s) could not be reached:
>
> msherman@??? on 3/24/2005 1:47 PM
>
> There was a SMTP communication problem with the recipient's email
> server. Please contact your system administrator.
>
> <to-exchsrv-01.fortiva.corp #5.5.0 smtp;550-Spam score too high
> (996.8). Contact postmaster@??? for>

The error message I sent back ended with " assistance." but that was too
long. So if you try to implement a c/r system using 550 responses to
send the challenge, the url to respond to the challenge had better be
pretty small.

- Marc