IPv6 ping for a multicast ff02::1 address

3 VMs attached to a common subnet. 

All VMs have a link-local fe80::/64 address assigned.

VM1: Ubuntu Server 13.10
VM2: Win7 x64 Pro
VM3: Win7 x64 Pro

Pinging the IPv6 multicast address ff02::1 with only Win7 VMs running inside the network:

C:\Users\qwerty>ping -6 ff02::1
Pinging ff02::1 with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.

Now bringing up the Ubuntu VM:

 C:\Users\qwerty>ping -6 ff02::1
Pinging ff02::1 with 32 bytes of data:
Reply from ff02::1: time<1ms
Reply from ff02::1: time<1ms
Reply from ff02::1: time<1ms
Reply from ff02::1: time<1ms

 a sidenote- use linux and ping6 so you dont need wireshark to see actual sources of replies.

Wireshark confirms that the replies are coming only from the Ubuntu VM.
Wireshark also shows that both Win7 VMs see the IPv6 ping requests, but for some reason they dont reply (even if the firewalls are disabled). A security feature of windows?

Just an interesting obervation.