Domain Mapping Question

We created a WP install on WP 3.0 and have MU set up. Got the plugin installed correctly.

The blog site is and the first blog we are doing is at

We want from to go to We configured everything in the backend of making the changes in the plugin screen and on the super admin menu.

The is on the same IP as the right now but we can't get the blog to show up. Getting a 404 error.

It is on a dedicated IP. Can't figure out what else we need to configure or may have missed.