[Enigmail] Unable To Import Public Key

[Carlos Williams]

On Wed, Nov 19, 2008 at 8:45 AM, Ludwig Hügelschäfer
<mlisten at hammernoch.net> wrote:
> As it turns out, this key doesn't have a signature at all. Just ask your
> partner to add a selfsignature and send the resulting key again.

How do I tell him to add a 'selfsignature' to his key? How can I tell
if my key contains a self signature also? This is so new and
confusing.