[Pluto-help] PDF

[JavaMan]

Ho scaricato i manuali della Intel in formato PDF ma pare che siano
criptati, sotto win con Acrobat li vedo, con xpdf mi appare questo
messaggio:

xpdf version 0.90
Copyright © 1996-1999 Derek B. Noonburg
Error: PDF file is encrypted and cannot be displayed
Error: * Decryption support is currently not included in xpdf
Error: * due to legal restrictions: the U.S.A. still has bogus
Error: * export controls on cryptography software.
Error: Couldn't read xref table

Come li vedo con xpdf?
Perchè li criptano??

Ciao a tutti,
jman