I run Adobe Acrobat 8 Pro and need a script that will expire PDFs within a certain time, or by a certain date, either way. After I print out a PDF, I send it to a client via email. When the client opens the PDF on his local pc, it needs automatically check an external/independent time source, a known website that keeps time (something like, but not necessarily [url removed, login to view]). I have used scripts that check the local pc clock, but this method can easily be manipulated.
No other security measures are needed.