Multisite domain maping is not redirecting to new domain

I have a multisite installation on a media temple(DV) server. I setup an alias for my new domain, and set the new domain in the domain mapping settings as the primary domain and I thought I’d be all set. However the new domain(domainB.com)is redirecting to the domain that has the multisite installation(domainA.com). This also means that domainA.com/domainB/ also redirects to domainA.

I feel like I must be close, but maybe I missed something? Any insight would be greatly appreciated!