DirectAccess Client Ping

hi,

I have enabled the ICMPv6 and Ipv6 also enable the port 3389. I can ping my DA Client Machine from my DA Server. But While pinging from a DA Client Machine to another DA Client Machine Connected on the Same domain and same DA server i am getting Request Timed Out. How is this possible to get ping response from one to another DA Client Machine.

thanks,

Roshan