[exim] Tls on connect as and SMTP Client

Hello All,
I deliver my mail using a smarthost router to my ISP - AT&T Yahoo DSL. They just sent a memo out that
effective March 1, 2007 they are requiring us to use TLS-ON-CONNECT on port 465 to send mail. I have read
the sections in the manual about TLS and exim as a client and didn't see anything that will allow me to
set tls-on-connect as a client. I know I can use port = 465 in the transport to force the traffic to
SSMTP port. Does this tls-on-connect option exist for SMTP clients?

Bill