[rt-users] Some questions with WebExternalAuth

[Randy]

Hello,
 
My users create tickets via a web form that i then send to the mailgate.
 
I would like to give my users access to the web interface to view their open
tickets.
 
In our system we already authenticate them, So from what i am reading, if i
set the REMOTE_USER var to their email address and set WebExternalAuth to
??? then it will let them in??
 
Is this a correct assumption. Is there any docs that help with this?
 
Thanks
Randy