cat /service/qmail-smtp/run
#!/bin/bash

exec tcpsvd -vv -t1800 \
   -c100 -C'10:421 per host concurrency limit reached\r\n' \
      -i/etc/opt/qmail/rules \
         0 25 \
            /opt/qmail/bin/qmail-smtpd \
               /usr/sbin/chpasswd /bin/true 2>&1