mailx on ubuntu

[Adil Hindistan]

Does anyone know how to configure mailx on ubuntu? I installed it:
sudo apt-get install mailx

As I would need to use my ISP's smtp address for sending out e-mails,
during the installation I chose Satellite installation and entered
smtp.comcast.net.

However, Comcast needs authentication to send out e-mail, so
I edited /etc/postfix/main.cf as per instructions I found here:
http://www.hserus.net/wiki/index.php/Postfix

I think I am missing the SASL installation part mentioned at
http://www.postfix.org/SASL_README.html

I'm getting lost at reading the document...

Anyone with experience on this?

Thanks,
Adil