I also found this out the hard way. It seems that my Apache setup on Ubuntu Server also requires me to set the RewriteBase.

I think this is a pretty well-ish documented thing, though. I seemed to find a solution within minutes after a couple of Google searches.

What I don’t understand, though, is that the use of RewriteBase doesn’t seem to break hosts that don’t initially require it to be set. For example, I develop websites with CakePHP on my home server (with RewriteBase), then upload it to a web host. I don’t bother removing the RewriteBase line from the production version, though, and it works just fine. So I don’t understand why it isn’t included in the CakePHP .htaccess files by default!? :-/