While researching Quercus today, I ran into some trouble running the new integrated Multi Site feature of Wordpress 3.0(previously a separate project known as Wordpress MU or WPMU for short) on Resin.
Quercus is a PHP implementation written in Java that runs on any Java Servlet Container, including but not limited to Jetty, Tomcat or Resin. I took Resin for it was the easiest to setup and includes Quercus.
Normally one would just use Apache and mod_php, but I also want to run Jython and Clojure projects, so I'm looking for a solution to combine these.
Wordpress MU allows me to run multiple blogs on a single installation(as seen on wordpress.com), which I want to use for hosting websites for my clients.
The problem with WPMU is that to map the different urls to one installation, some tricky mod_rewrite code is required for Apache, but since I'm using Resin here, I'll have to find another solution.
There is a post on the Quercus wiki describing the process of setting up a Multi Site Wordpress installation, but this is for an old version of WPMU(before the merge) and an old version of Resin.
After a good few hours of trying, I got it working with the latest version of Wordpress 3.0, Quercus 4.0.3 and Resin 4.0.7.
Just follow the wiki, except for a few points: