Kerberos protocol registry entries and KDC configuration keys in Windows Server 2003
http://support.microsoft.com/kb/837361
Kerberos Authentication Tools and Settings
http://technet.microsoft.com/en-us/library/cc738673%28WS.10%29.aspx#w2k3tr_kerb_tools_iybi
ClientIpAddresses
Registry path
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\Kerberos\Parameters
Version
Windows Server 2003, Windows XP, and Windows 2000
This entry controls adding IP addresses in KRB_AS_REQ, thus forcing the Caddr field to contain IP addresses in all tickets. This entry does not exist in the registry by default. The default value is false, due to potential DHCP client and network address translation (NAT) issues.