Virtual Server 2005 Licensing in depth...

Licensing Microsoft Server Products with Virtual Machine Technologies Licensing Brief
This licensing brief provides an overview of changes to Microsoft’s licensing models for the server operating system and server applications. The purpose of these changes and clarifications is to help you understand how to use Microsoft server products with virtual machine technologies such as Microsoft Virtual Server 2005 R2. For more details, please review the Virtualization Whitepaper     

Virtualization Brief.doc

Licensing Microsoft Server Products with Virtual Machine Technologies Whitepaper
This whitepaper provides an in-depth review of changes to Microsoft’s licensing models for the server operating system and server applications. The purpose of these changes and clarifications is to help you understand how to use Microsoft server products with virtual machine technologies, such as Microsoft Virtual Server 2005 R2.