Actionmailer and postfix settings


I am having problems configuring my actionmailer to work with postfix.

I followed this tutorial:

and i got the server set up.

at first i fixed the mail settings to work with gmail using this

and my app worked with gmail.

but now i want it to work with my newly built email server. I read
somewhere if your server has tls u have to do something special with
actionmailer for it to work so i am relying on fischer's workaround.

so i inputed this into the mailer.yml file that danielfischer created:

    :address: localhost
    :port: 25
    :domain: localhost
    :password: secret
    :authentication: :plain
    :tls: true

Should i have used mydomain instead of localhost?
I just can't seem to get it to connect there is nothing in my tail -
f /var/log/maillog error
Please help!