Getting sendmail use gmail as a relay.
I did this a while a go, when i was getting asterisk to forward my home voice mail to me and my wifes email address’.
Add the following to your sendmail.mc
define(`SMART_HOST’,`smtp.gmail.com:465′)
define(`confAUTH_MECHANISMS’, `EXTERNAL GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN’)dnl
FEATURE(`authinfo’,`hash /etc/mail/auth/client-info’)dnl