sendmail smtpauth

[Michael Thomas]

I want to set up smtp auth to authenticate me using my x509 certificate 
from the SSL connection established by my mail client (thunderbird).

Is this possible with the sendmail package in FC4?
If so, can anyone point me to some documentation on how to set it up?

Googling on "sendmail x509" pointed me to sasl, which I currently use 
for password-based authentication.  I tried searching for "sasl x509" on 
google, but only came up with some old mailing list posts from 2000 that 
discussed some implementation scenerios.

--Wart