Well I've been banging my head against the wall trying to get the Simplenews module for Drupal working properly after having to move hosting providers.

The issue was partly of my own desire to run PHP 5.2 on CentOS 5.x. After moving providers I wanted to get my new VPS ready to run Drupal 7 when it's released and it requires PHP 5.2.

If you have recently updated to the most recent mod_security RPM from Fedora and you are running Drupal, you've probably noticed that certain things don't work correctly. Most specifically, some of the system CSS pages and tabs look funny, and if you're using the pathauto module with the default URL aliases you are probably get a Forbidden (or HTTP 403) when you try to access your content.

First some background about web applications firewalls for the uninitiated. If you already know what a web app firewall is then you can skip down to the bottom of the post for some mod_security rules that will help you with Drupal Views, the GMap module admin pages, and Google Webmaster Tools.