I'm surprised no one has mentioned Crypt::OpenPGP. It appears to be a full-featured Pure-Perl implementation.

However, I must admit in my own efforts to start using it recently on FreeBSD, I've run into what appears to be a bug in the software, related to the Crypt::Random module. (I did get it working fairly easily on Linux once before).

Does anyone have any comments on Crypt::OpenPGP while we're on the topic?

-mark