public key cryptography

[lyn]

hi,

I'm researching an idea for a secure voting system which I'd like to
develop in erlang and give away for free.  I plan to use public key
cryptography (pkc) to guarantee the security of the system.

Has anyone developed any systems in erlang which use pkc?
Does anyone know where to find a freely available implementation of
a pkc library (C is fine), suitable for such an application?

Could I distribute that library along with my application (I am a US
citizen in the US)?
If not, is the best approach to simply distribute my application
separate from the crypto library, then have users download the library
and do a "make crypt-bindings" which compiles the necessary erlang-C
glue?  This would make it legal to distribute my (secure) application,
right?

answers or pointers much appreciated,

-Lyn Headley