Domain mapping - disable by default?

So, I've got the WHMCS WordPress provisioning working, but when it creates a site, it automatically maps the domain name by default. In most cases the domain name isn't active or transfered yet, so I'd like domain mapping to be active on the multisites for sites that are using it, but for new sites to not have an active domain mapping entry by default (even when it's entered in WHMCS). Any ideas?

- fox jones