I don't know if ViaCrypt includes any distinguishing features that let you tell a ViaCrypt PGP message from a Real PGP message - they could do subtle stuff like make the session keys all include some checksum (e.g. be a multiple of N mod M), or crude stuff like put "Version 2.3ViaCrypt" in the headers, which would let them detect non-ViaCrypt PGP users. I assume not, but I haven't seen it.

PRZ has specifically said that it is his intention to have no difference between the output of the PGP and ViaCrypt so that users of the free-ware version can't be ferreted out. ----------------------------------------------------------------------------- Michael S. Sattler msattler@netcom.com +1 (415) 358-3058 Digital Jungle Software Encrypt now; ask me how. (finger for PGP key) "Don't Panic!" -- Douglas Adams "Don't Panic. Stay Cool." -- PRZ