user configurable relay-only MTA

 ESMTP is a user configurable relay-only Mail Transfer Agent (MTA) with a
 sendmail-compatible syntax. It's based on libESMTP supporting the AUTH
 (including the CRAM-MD5 and NTLM SASL mechanisms) and the StartTLS SMTP
 extensions.
 .
 ESMTP does not receive mail, expand aliases or manage a queue but can deliver
 mail locally via an MDA.
 .
 This package contains the esmtp program.