For the server to be able to decrypt it to run, there must be all the instructions required and encryption keys recorded. For someone who can read PHP, it's a simple matter to modify the PHP to decrypt and print to a text file instead of decrypt and run. For simple output there is a quick and easy workaround: My company does a news package using php, but instead of putting the code on their domain, we use an external javascript file called with '<script src=http://www.hostname.com/news/client0034.php3></script>'. The php script just does it's stuff and outputs a javascript file that uses document.write to output to the html page. It's not comprehensive, but for simple jobs it's ideal, no-one ever gets to see the PHP.
Hope that helps
Jamie
