What are the Active directory requirements to install Exchange Server 2007?

1. Domain functional level at least windows server 2000 native or higher.
2. Schema Master must be run on windows 2003 server with sp1.
3. At least one Domain Controller, in each domain with windows server 2003 sp1.
4. At least one global catalog server in Active Directory Site which hosts exchange Server 2007.
5. 4:1 ratio of Exchange processor to global catalog server processors.