Howtoforge published a guide about setting up CentOS 5.2 server with ISPConfig 3

This tutorial shows how to prepare a CentOS 5.2 server for the installation of ISPConfig 3, and how to install ISPConfig 3. ISPConfig 3 is a webhosting control panel that allows you to configure the following services through a web browser: Apache web server, Postfix mail server, MySQL, MyDNS nameserver, PureFTPd, SpamAssassin, ClamAV, and many more.

The Perfect Server - CentOS 5.2 with ISPConfig 3