Sendmail without the Superuser - As an exercise in the application of the concept of least privilege, we have modified the pieces of an ordinary UNIX* mail system, sendmail in particular, to require little or no privilege in their operation. - http://www.usenix.org/publications/library/proceedings/sec4/carson.html
Setting up sendmail on a firewall, Part 3 - This final article in the series covers installation, optional features, and testing techniques. An example of configurations for a special situation is described. - http://www.sunworld.com/swol-06-1999/swol-06-security.html
Setting up sendmail on a firewall, Part 2 - This article covers the intricacies of sendmail configuration file and shows you how to generate, build, and test a config file for your firewall. - http://www.sunworld.com/swol-05-1999/swol-05-security.html
Setting up sendmail on a firewall, Part 1 - This article discusses the implementation of sendmail on the firewall and focuses on features new to sendmail 8.9.3. - http://www.sunworld.com/swol-04-1999/swol-04-security.html
Sendmail Security - This page briefly describes how to setup sendmail to run without ever having root security - http://www.coker.com.au/~russell/sendmail.html