When you get the real answer, come back and tell us!
It seems to me writing or printing to a postcript file should work. I just tried this with one of my Acrobat files, created from a Word document into which I had pasted two vector files from my spice program, a schematic and some data plots.
I opened the file in Acrobat and did a Save As, specifying a PostScript File (*.ps), and then I opened that file with a text editor, and there were the ASCII PostScript commands, including all the vectors with location info. You'd have to learn some PostScript to manually parse the commands, and extract the information. The .ps file was 4400 lines long. :-) Hmm, I'll bet there are plenty of free programs that'll do that task for you. Let us know what you find out.
I think you can also print from Acrobat reader to a PostScript printer, but clicking "print to file" in the dialog to get an ASCII .ps file.