User domains...

I have a user who wants to start blogging with us instead of wordpress, but they have their own domain name and want to use that - is there any plugins or elgg features that can do this so that instead of the domain redirecting to us it can be mapped against the folders, so his blog URL's would all be @ his name instead of changing to our domain name.

Also, anyone know if there is a wordpress to elgg blog import tool?