Why no PHP API binding?
Try it:
http://www.tokyomuslim.com/2010/04/php-class-to-run-pdfcrowd...
I don't blame anyone for not wanting to use PHP's poorly documented CURL classes.
The place where it reallllly irritates is the cookie management, but thankfully I didn't have to deal with that in this case. (I did for a client at a newspaper - nightmarish.)