SMTP Authentication

[Mike Jeays]

How do I tell sendmail to provide an authentication string when I ask it
to send messages to my ISP (a cable provider)?  They use PLAIN
authentication, and I did not have too much trouble getting the base 64
string by snooping with Ethereal when I sent mail from Evolution, and
can send out emails "by hand" or from an Expect script.

The relevant part of my sendmail config file is:

define(`SMART_HOST', `smtp.broadband.rogers.com')

set SASL options
TRUST_AUTH_MECH(`GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN')dnl
define(`confAUTH_MECHANISMS', `GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN')dnl
define(`confDEF_AUTH_INFO', `/etc/mail/auth-info')dnl

There doesn't seem any way to tell it what my userid and password for
the ISP should be.

I have tried reading various documentation, but haven't been able to
find what is required.