Howtoforge posted a turotial about managing a Virtualbox installation with phpvirtualbox on CentOS 6.2

phpvirtualbox is a web-based VirtualBox front-end written in PHP that allows you to access and control remote VirtualBox instances. It tries to resemble the VirtualBox GUI as much as possible to make work with it as easy as possible. It is a nice replacement for the VirtualBox GUI if you run VirtualBox on headless servers. This tutorial explains how to install phpvirtualbox on a CentOS 6.2 server to manage a locally installed, headless VirtualBox.

  Managing A Headless VirtualBox Installation With phpvirtualbox (CentOS 6.2)