running sips via Perl/PHP system function

Hello all, I am wondering if anyone knows what changed from Panther to Tiger that would cause failure when attempting to execute certain utilities via the Perl/PHP system() function? Specifically I am trying to run sips via a web-based application. Right now I am just trying to get it to take an uploaded image and generate a thumbnail for me. Now, on Panther server, it works great. No problem running it via my browser. However, on Tiger server, if I try to run via my browser, it fails. I CAN run it on command line successfully. So, I am trying to figure out what changed as far as interaction and permissions. Apache runs as "www" user, however I have permissions pretty well wide open while trying to get this thing to work. Any help, suggestions, criticism is warmly welcomed. :)