See the following document for details on how to configure Server Core on Longhorn (aka Server 2008).
http://technet2.microsoft.com/windowsserver2008/en/library/47a23a74-e13c-46de-8d30-ad0afb1eaffc1033.mspx?mfr=true
Microsoft is conducting an online survey to understand your opinion of the Technet Web site. If you choose to participate, the online survey will be presented to you when you leave the Technet Web site.
Would you like to participate?