One more advantage is Replacement for sendmail : qmail offer host and user masquerading, full host hiding, virtual domains, null clients, list-owner rewriting, relay control, double-bounce recording, cross-host mailing list loop detection, per-recipient checkpointing, downed host backoffs, free message retry schedules, etc. qmail offer a drop-in ``sendmail'' wrapper so that it will be used transparently by your current Uas.
