"Identical" PDFs are not necessarily byte-identical; you can't just check equivalence through checksums. (AFAIK, it's been a while, feel free to correct) I do

"Identical" PDFs are not necessarily byte-identical; you can't just check equivalence through checksums. (AFAIK, it's been a while, feel free to correct) I don't remember a good way to normalize/disambiguate, at least I never attacked the problem long enough to have learned. EDIT: oh yeah, I'm pretty sure it contains Mail, just like Zawinski said