Domain Mapping on a Virtual Server

I am setting up my Wordpress MU and I have purchased a virtual server account. When I tried this on a shared hosting account the domain mapping wouldn't work unless I added the domain name to my hosting account. Does anyone know if it will work now on virtual server without having to add it to the hosting account? Essentially I would like for it to be where my clients could map the domain name themselves through the WP dashboard account and adding the IP and nameservers to their domain name. Is that possible or could someone point me in a direction on how to make that possible.