Hi Jerry,
This is a known issue. The issue is caused because of the new cluster failover mechanisms (a network adapter for internal cluster communication) introduced in MS Windows 2008 R2. To learn about, and resolve the issue, please refer to the below mentioned SAP Notes:
1365796 - Local host name resolution fails in Windows Failover Cluster - To resolve the issue.
2109662 - Windows returns wrong IP address as source IP - To learn more about the issue.
Cheers!
Hemanth