Manually setting Pine up to use GPG for encrypting and clearsigning messages on SDF Public Access UNIX Systems:

Assumption: you have already generated your GPG secret key, etc. (http://www.gnupg.org) 

(1) cd .gnupg/

(2) ln -s /sys/pkg/bin/gpg gpgencrypt; ln -s /sys/pkg/bin/gpg gpgclearsign

(3) cd ..

(4) run pine

(5) Enter setup (M for main menu, S for setup).

(6) "C" Go into the Config menu

(7) arrow down til nearly towards the end.

    Edit "display-filters" (ie. highlight it and type "a"
    Add these two filter rules (ignore the line numbers): 

   1. _BEGINNING("-----BEGIN GnuPG MESS")_ /sys/pkg/bin/gpg -d
   2. _BEGINNING("-----BEGIN PGP MESS")_ /sys/pkg/bin/gpg -d 

(8) edit the sending filters in the same manner:

   1. ~/.gnupg/gpgclearsign --clearsign
   2. ~/.gnupg/gpgencrypt -aes -r _RECIPIENTS_ 

To use it:

    Upon sending the message with ^x, you should be able to scroll through
    the various filters (with ^n and ^p).

(Unfortunately, this setup does not allow unencrypting of received mail. Only encrypt or sign sending mail.)