Move Joomla configuration.php from public folder

Many howtos on Joomla security talk about moving configuration.php outside the web (public) folder. When I refer to the new location via absolute path or other ways I tried (/../foldername), the site can't see the file. I've had to resort to moving the file to a sub-folder of the public folder which isn't what I would like.

Is there a way to accomplish what I want to do?

Running ISPConfig 3 on Ubuntu 10.04 howtoforge perfect server.

 

Did you add the new directory to the PHP open_basedir field on the Options tab of your web site in ISPConfig?