Using Domain based namespaces on DFS cluster

Hello all.

So I have created a DFS cluster and want to move my old DFS from 08 R2 DFS server\\domain\name, but as I try to add a domain namespace to cluster I cant, the only way is to add a standalone namespace?

My idea is to move files using an replication group and then shutdown old system, with DFS namespaces intact, thus not harming users, any tips on achieving this?

Thx