Microsoft has fixed the DHCPv6 bug in SP2 for Windows Server 2008 and Vista (download). The bug “It mangles DNS search domain lists (e.g., "foo.psu.edu, bar.psu.edu, psu.edu"). Windows 2008 SP 1's DHCPv6 server malforms the list, and Vista SP1 expects the list to be malformed. Things work fine if you have Microsoft DHCPv6 software everywhere, but in mixed environments, the DNS search domains will get broken,” revealed.