I have a customer with 1 existing Server 2003 std as DC. Now he purchased a 2008 SBS to run Exchange and 2 additional 2008 R2 std as file server and Terminal service. Can I have both the old 2003 running as DC and the new SBS 2008? Or do I have to DCPROMO the 2003 server to just be a member server? Can I have any extra DC server running along with the 2008 SBS?