Basically, if both commercial PGP and freeware PGP produce exactly the same encrypted files as output based on the same keys, and if you have the source code and can trust freeware PGP, then it can be stated that commercial PGP is secure.

pgp and viacrypt will always generate differnt outputs: pgp adds some pseudo-random stuff to the start of the file it is encrypting to ensure that a file encrypts differently each time. peter