[Dovecot] dovecot sieve sends vacation messages with null envelope sender

[Stephan Bosch]

Josef Liška schreef:
> But it sends vacation messages with null envelope sender, which is in 
> my opinion undesirable, because many vacation messages are caught in 
> spam filters.
>
> I think there could be same sender on envelope.
> In dovecot-sieve/src/sieve-cmu.c around line 380 is a call to 
> smtp_client_open(src->addr, NULL, &f);
> NULL could be replaced with src->fromaddr
>
> [...]
>
> Summary:
> I expect messages sent by vacation recipe should have envelope from 
> same as user's e-mail address. This is then writen to Return-Path: 
> header by receiving MTA
>
> NULL envelope from is used, resulting (in my case) to Return-Path: <> 
> rewriten by postfix to Return-Path: <MAILER-DAEMON> by receiving MTA
Interesting. I've seen a very similar suggestion yesterday. However, as 
I explained in the previous post, the use of a non-null envelope from 
field is discouraged by the Sieve vacation RFC (5230) and also by a more 
generic RFC (3834) describing the do's and dont's regarding auto-responders:

http://www.dovecot.org/list/dovecot/2008-August/032799.html

It puzzles me why spam filters would reject messages with a <> return 
path, which is a very common an valid use of the SMTP protocol. What 
spam filter are we talking about anyway?

Regards,

Stephan.