Help to find information to imlement game server GPG usage

[Millis Miller]

Hi,
I have a project which is essentialy a email-based game ajudicator, that recevies instructions by email and sends their results alos by email to players. At the moment, it is using clear-text email, which has sufferend from a number of spoofing/fake identity issues. I am thus looking to use email signing/encryption to get around this.

On the email sending side, I am using the email program (http://email.cleancode.org) to send emails, but I cannot find out clearly how to decode incoming signed (and possibly encrypted) email automatically.

At the moment, I have a .forwards that sends all email to the program to parse. I'd like to have that email preprocessed so that it can:
 - decrypt it if encrypted
 - check the signature if signed
and pass the post-processed email to the program (adding say some X-Headers to say if the signature was good/bad etc.).
How can I do this (bearing in mind that emails are normally MIME encoded by email clients when signed/encrypted)?

A second question is that I'd like to have the program automatically encrypt emails when sending to people if possible. Is it a better solution to have a local keyserver (pks) to control these keys, or provide a mechanism to directly place keys onto the ajudicator's keyring?

I am not looking for an indepth solution, just some pointers as to what the best methods would be, as by just using munpack/gpg on its own, I don't seem to be getting anywhere.

Many thanks,
Millis