I've been working on a site which uses the CodeIgniter PHP framework for a few days.
I added a custom CMS area to the site, which I wanted to place in a password-protected directory. I needed to turn the Rewrite Engine, (which CI uses extensively), off for the CMS' URL but for some reason Apache throws a spaz if you try to use the 'RewriteEngine off' directive along with the 'require valid-user' directive.