Hello, Our main mail system includes one database server (postgresql), 2 mx hosts for processing Internet-inbound mail and 2 pop3/smtp hosts for our customers. All running debian, on i686. We've kept pretty up-to-date on dbmail 1.0->1.1->1.2 series code, always with custom patches, but are working on getting those integrated into the official codebase. There are approx. 5000 users, and we do spam scanning, etc. (We'll provide weDBmail on these servers too, as soon as we get pgsql support, but right now it's overkill on horsepower.)
We also have one standalone mail server running dbmail on mysql on an i686 debian box and another on a Sparc64 debian box. Very few users on both of those. -- Jesse Norell jesse (at) kci.net