apache 2.2 - Mac OS X Mountain Lion adding www to virtual host on localhost

I'm new to configuring my Mac for localhost so this may be a dumb question. I want to set up a virtual host so that http://localhost/domain points to http://domain.dev. In my Apache configuration, I have localhost pointing to my Sites folder. That works correctly. I can browse to localhost/domain.

In my hosts file, I set up domain.dev as 127.0.0.1.

In my vhosts file, I set up the following entry:

DocumentRoot "/Users/username/Sites/domain/"
ServerName domain.dev

But when I uncomment this line in the Apache configuration:

Include /private/etc/apache2/extra/httpd-vhosts.conf

The browser adds "www" to the domain.dev, which it then can't find. What am I doing wrong?

Answer

Just use ServerAlias.

   DocumentRoot /Users/username/Sites/domain/
   ServerName domain.dev
   ServerAlias www.domain.dev