Howtoforge posted a tutorial about setting up ownCloud 4.0 on CentOS 6.2

This document describes how to install and set up ownCloud on CentOS 6.2 on an nginx web server and php-fpm with postgreSQL database as backend. For other distributions there might be minor changes as to the software prerequisites installation procedures. This guide will not only help install the product, but also understand why certain points are done the way they are done.

  Your Cloud, Your Data, Your Way! - ownCloud 4.0 On CentOS 6.2 + nginx + PostgreSQL