Domain Mapping subdomain redirection

Hi, I have installed the "Domain Mapping" plugin to allow the use of domain names.

Now my subdomain redirects to the domain. I don't want this behaviour. I would like the subdomain to continue working as subdomain but the domain also to work.

At the moment I have the websites being provisioned by WHMCS MU Provisioning plugin. So I would like the system to create the subsite automatically with the desired option, any indications on how to force this change on signup?

The reason I want to do this is because sometimes a domain is not yet registered or pointing to our servers and I would like the users to be able to preview the subsite immediately after signing up.

Could you send a suggestion how to change this?