Mail Server Setup on Amazon EC2

I have an Amazon EC2 instance running Amazon Linux with a basic LAMP stack. I would like to have smtp, pop3, image and webmail services installed. Here are some of my requirements for the mail server… 1. Must support Imap so that I can store my mail locally on the server 2. Must support pop accounts 3. Must support multiple domains and multiple mailboxes per domain 4. Must support the ability for address forwarding and auto responders 5. Mail boxes and domains should be managed through MySQL 6. Some type of webmail (Squirrelmail, Roundcube, etc) should be installed for accessing pop accounts 7. Spamassasin should be installed I'd prefer Postfix smtp server and Dovecot pop3 and image server, but am open to other mail software if you feel it is better. In addition to the installation of software to meet the above requirements, the following are also deliverables for the project… 1. A brief guide on what you did (software installed, configuration file paths, etc) to get all this setup. This is more for my curiosity as I like to learn more about this stuff. 2. A brief guide on how to add new mail boxes across various domains for both pop and imap accounts. This should also include how to setup mail forwarding and auto responders. 3. Location of webmail 4. A brief guide on configuring Spamassassin. Can I configure it differently for different mail boxes or domains and if so, how? I have a strong technical background but have had a tough time getting the email server setup. Given my technical background, I don't require very detailed documentation. I just need basic overviews on where to access configuration files and basic usage. I'm even comfortable being provided with links to only documentation to walk me through the process. Please feel free to ask any technical related questions throughout the project if you feel it will save time on the project.