http://support.microsoft.com/kb/2845152/en-us
这里有个HOTFIX,装一下,看上去和你遇到的问题一样.
This issue occurs because the ID that NAT64 uses for an ICMP packet and the ICMP ID that is generated from the local stack both start from 1. Therefore, NAT64 incorrectly forwards the ICMPv4 Echo Reply message back to the DirectAccess client, even if the message is for the DirectAccess server.