Thanks for the response! To answer your questions and suggestions…
-Using shell I typed ‘which php’ and that gave me the /usr/blocal/bin/php. Should I change to what you noted above anyway? Using my phpini file it seems I am running php version 5.2.17.
-I enabled file permissions on the php script through my FTP client to 777 for testing purposes. I initially tried “chmod a+x picture_inbound.php” while in that specific file’s directory but noticed when checking the file permissions in FTP that none of the options were set to execute so I figured it might be safer to switch back to 777.
-To try piping the test.txt file, would that have to reside in the same directory as picture_inbound.php? That seems like an excellent way for me to test the script and .forward.postfix file.
-By prepending shebang line do you mean something like this “#!/usr/local/bin/php” prior to the <?php bracket in the php script? I do have that particular line there.
Sorry for what are probably simply questions but, I’m really new at this.