GPG: Encrypting messages in Apple Mail
GPGMail is a plug-in that enables the sending and receiving of encrypted emails in Apple Mail. It works in Tiger and Panther, and acts as a front-end to macgpg, the Mac port of an open source encryption engine, gpg. You will need to install macgpg first.
After installing GPGMail, you will find a new sub-menu under the Message menu, from which you can manage your digital signatures and other encryption options. The developer’s website provides a list of the plug-in’s limitations, including the fact that encrypted messages are just stored by Apple Mail and not indexed.
It is freeware and is available from the developer’s website.
Joar Winfors provides some background on his site about using digital signatures in Apple Mail.
UPDATE: GPGMail 1.1.2 released, 5 February 2006.
Tags: Apple Mail, encryption, GPG, GPGMail, mail.app, messages, PGP, pluginRelated posts

February 5th, 2006 at 2:44 am
I had to uninstall this plugin because Mail.app kept marking my read mail as unread with it installed.
October 3rd, 2006 at 10:09 am
same for me, my mails show up as unread :(
but it works perfect except for this little problem.
May 17th, 2007 at 2:30 am
Unfortunately it doesn’t work at all with Mac OS 10.4.9 - plugin is disabled automaticaly by apple-mail during its startup - some compatibility problem.