You will need to install the following updated management pack the will detect Windows 2008.
You will also need to install the following hotfixes as of 4/2/2009
- 953290 – An application may crash when it uses legacy methods to query performance counter values in Windows Vista or in Windows Server 2008
- 951116 – A memory leak occurs in performance counters that are used to monitor Windows Server 2008-based computers
Read more @> Installing An OpsMgr 2008 Agent on Windows Server 2008 – Windows Live