El mail tarda hasta 30 segundos o mas en enviarse

For Red Hat servers the -Rt0 option needs to be added to the beginning
of the server_args line in the /etc/xinetd.d/smtp_psa file:

server_args = -Rt0 /var/qmail/bin/relaylock……

It is necessary to restart xinetd since the changes will take effect the next time SMTP is used.