The version of sendmail that is included on the release is Version 8 compatible. The new version fixes some security holes and includes several improvements to Version 5. Several extensions to the standard BSD release have been added, including name service switch and NIS+ support.
The mailbox spooling directory has been moved from /var/spool/mail to /var/mail. A new directory, /var/mail/:saved, is used for creating locks and temporary files by the mailx program. Also, the mail configuration files are now all located in /etc/mail. The new directory includes the aliases and the sendmail.cf files.
The mailbox locking mechanism has been enhanced so that Solaris 7 clients can safely mount mailboxes from both Solaris 2 and SunOS release 4 mail servers. This enhancement eases administration of mail, especially in large sites.
In the Solaris 7 release, /usr/bin/mailx supersedes /usr/ucb/mail. The mailx program has been enhanced to behave the same way as the SunOS release 4 version of /usr/ucb/mail. The /usr/ucb/mail file is now a symbolic link to /usr/bin/mailx.
In SunOS release 4 releases, a program called sendmail.mx was used in DNS sites to access mail exchange records. The new version of sendmail includes the needed functionality and can be configured through /etc/nsswitch.conf.
Mail Administration Guide describes the administration of sendmail.