PHP 500 Internal Server Error

[suzkaw]

I have created a classifieds script that works fine on my server which has PHP running under apache. Now I have a customer that is trying to use it with PHP installed as a cgi and on several pages it works fine then others it throws out a Internal Server Error. Do you have any ideas on what would cause this?
Or maybe any links to what I should look for when programming for both?

[suzkaw]

I figured out the problem. I had the script encoded with IonCube and once I removed it, it ran fine.