I have now created a basic How To for the desired configuration on the 2.0 Wiki. Although it has some 2.0 specifics it should work with 1.2 for most parts too. Maybe someone with a higher privilege level on the Wiki than I have can beautify the URL by removing the Whitespaces :)
http://wiki2.dovecot.org/HowTo/Virtual%20User%20Flat%20File%20Configuration%20with%20Postfix Regards Thomas
