I have just spent an hour or three installing two Windows 2008 Enterprise Edition boxes to create an Exchange 2007 SCC cluster using Microsoft Virtual Server 2005 R2 to create the environment.
But I did not get that far, as Windows Server 2008 Failover Clustering shared storage requires SAS (Serial SCSI) or iSCSI and not traditional SCSI (Parallel SCSI). Microsoft Virtual Server 2005 R2 only emulates IDE (not supported for clusters anyway) or Parallel SCSI. So I could not create a failover cluster with shared storage tonight.
I will install the iSCSI target that I have and try again in a few weeks.