We run 1.8d on a Solaris 2.8 with sendmail, and have web front-ends for
regular users to create and delete lists.  The scripts create files in a
special place that get picked up for nightly rebuilds of the sendmail
aliases file. It could be more frequent but the delay allows us to catch
errors and users to populate their lists while they wait to use them.
We have a C program that allows only a certain ID to install a new
aliases file.

Eva Kalman
Lucent Technologies