SMTP feed -- SMTP Fast Exploding External Deliverer for Sendmail

Smtpfeed is a SMTP delivery agent which is called by sendmail, and it
improves required time to complete delivery of copies of a message to
recipients of huge number.

This delay of delivery by sendmail causes by the fact that implementation
of SMTP delivery routine in sendmail processes all delivery in a series.
By this reason,  when it takes long time for delivery to one recipient
which is in a huge list, delivery to following recipients is greatly
influenced.

To avoid such a problem, delivery agents should be implemented so that
a delivery is not influenced by preceding delivery: DNS query and
SMTP delivery par destination should be processed in parallel.
Smtpfeed is the SMTP delivery agent for sendmail implemented with this
idea.