I have an existing network with Active Directory running on 2 Windows 2000 servers. I have just received a Windows 2003 server and have joined it to my domain. I plan on installing Exchange server 2007 in a few days or so on this new server and phasing out an old Exchange 5.5 box. I would like to demote one of my current DC machines and add the 2003 server in its place as a new DC for the existing domain. Are there any problems introducing a W2K3 server as a DC to an existing 2K AD environment? Will the 2K3 server automatically assume the necessary roles in this scenario? Will it play nicely with the other 2K DC and XP clients?