I noticed on Rackspace, when using an Ubuntu instance (10.04; standard LAMP setup), the ".php" suffix on a URL is optional. ie www.example.com/thispage loads thispage.php
When I setup a very similar server on Amazon (default AWS 32-bit ami; a flavor of CentOS/Red Hat) and locally on osX 10.6, the ".php" suffix is required. www.example.com/thispage returns a 404 error, while /thispage.php loads the file as expected.
The most likely cause, in my mind at least, is that there are different default settings in php.ini or the Apache configuration between these different setups, but I can't figure out what it is. Can anyone explain to me where this difference comes from?
NOTE: I know this can be overcome using mod_rewrite, I'm just curious as to this difference in the default configurations.