EMail Server Cluster Setup

We need a mail server cluster setup written as shell script for servers running Ubuntu Server 12.04 / 13.04. Description in detail: - There shell be one server ([login to view URL]) that is responsible for IMAP / SMTP connections (no POP3 needed). This server shell run a reverse proxy (preferable nginx) to connect with several mail box servers ([login to view URL], [login to view URL], ...) to split the workload, especially for SMTP traffic / sending many emails at once (newsletter). - The setup shell check for malware (clamav?) and spam. - Mailboxes shell be kept consitently available over all servers as there will only be a few mail accounts but some with high traffic (support / monitoring). - Useres shell be authenticated by a mysql table containing username and password. - It shell be possible to add new servers in order to keep the system scalable, preferable with a mysql table but not neccesserally. - TLS / SSL for IMAP / SMTP required. Forbid unencrypted connections. Please setup such a system on your own virtual machine environment using clean Ubuntu Server (!) 12.04 / 13.04 machines and feed us with shell scripts and information where to change details (i.e. setting the domain or certificate) (and terminal commands if needed) for each server so we can reproduce your work. We cannot let you setup the servers for us as part of our security commitment.