Two programs need to be executed as root no
matter who runs them. One is sendmail (prior to
V8.12), and the other is mail.local. Should one
or both of these programs have to run as a user other than
root, you can redefine the user with this
Note that this is just half of the solution. You will also need to
tune the appropriate F=S delivery agent flag (see
F=S for a description of how to do this).