It seems to me that this is a mail client question, not a BackupPC
question.
I know and ... honestly: I posted here in the hope that someone could
suggest an alternative way to send notifications from BackupPC, because
I went insane trying to send attachments with sendamil provided by
Postfix
This part, at least, I can explain: mutt (and mail) knows nothing about
the aliases in /etc/aliases. It only knows its own aliases (defined in
.muttrc).
Thanks a lot!
To give something back to the ML, here's how to send an attachment with
sendmail postfix (finally i got it): this is the scr