GPGMail

GPGMail is a plugin for OS X's Mail.app, which let's you
send and receive secure, OpenPGP encrypted and signed messages.

This is a build without the License Activation.

Prerequisite

Install the GPG Tools Package from the GPG Tools Website.

git clone https://github.com/otozyon/GPGMail.git
cd GPGMail

cd Dependencies
git clone https://github.com/GPGTools/Libmacgpg.git
make
cd ..

make

Quit Mail.app and then copy build/Release/GPGMail.mailbundle to /Library/Mail/Bundles/.

Start Mail.app, go to Preferences > General > Manage Plugins and choose GPGMail.mailbundle and then Apply and Restart Mail.