You are correct, omitting the -f option results in the From being set to MAILER-DAEMON however dovecot-lda is being executed with the -d and the -f option by my sendmail.
In my sendmail confgiuration I have... FEATURE(local_procmail, `/usr/local/libexec/dovecot/dovecot-lda', `/usr/local/libexec/dovecot/dovecot-lda -d $u -f $f') This supplies -f with the sender's address . When I execute dovecot-lda from the command line with the -f option set, the >From becomes MAILER-DAEMON even though it should be the value passed via -f . --Dave