Full installation of SIMS removes the Sun Solaris sendmail and installs SIMS IMTA. Stand-alone (pure) proxy installation, however, leaves sendmail configuration intact. This allows sendmail to listen for incoming SMTP connections. Since sendmail is not a SIMS component, the users or aliases that are defined in the SIMS directory may not be recognized by sendmail.For this reason, it is strongly recommend that you disable sendmail from listening for incoming SMTP connections on your proxy server by using the script /etc/rc2.d/S88sendmail. You may delete, move, or edit this script.
After you have disabled sendmail, its binary files will still be available to applications that may use it for outgoing mail.
Note - If your Proxy server is a smarthost in front of the firewall, you do not need to disable your sendmail.