Broken Web Sharing / Apache on OSX Leopard

I recently installed Leopard on my macbook and wanted to enable Web Sharing but when I visited http://localhost, Firefox gave me the following error:

Failed to Connect
Firefox can't establish a connection to the server at io.

I tried to uncheck/check Web Sharing in System Preferences. I also tried stopping/starting Apache on the command line with no luck.

Finally I used this resource on DIYMacServer to reinstall Apache on my machine. It now works like a charm, thanks Richard!

(This all came about because I want to install SilverStripe which suggests using MAMP, but I did not want multiple versions of Apache installed on my machine.)