If you run into problems using ActionMailer > 2.2, Postfix and OpenSSL while sending mail from your application, try changing the following:
vim /etc/postfix/main.cfChange
smtpd_use_tls=yesto
smtpd_use_tls=no
OpenSSL support with Postfix does not work out of the box. You can either generate valid certificates or tell Postfix not to use the certificates. More information is available in this discussion forum.
Just finishing up brewing up some fresh ground comments...