Is there really any privacy preserved by concealing the IP of a DNS query? The next thing you are going to do is contact the resulting host (probably controlled by the same people as the DNS server) with your IP in the sender IP field.<p>I suppose one could imagine a situation where a user is using some sort of anonymizer for their HTTP traffic, but not their DNS. DNS anonymizers are trival. Just don't implement this feature, or I suspect your client resolver code could prefill the RR with a bogus entry.<p>I've run my own DNS servers for years with the side effect that the authoritative DNS servers and their slaves get to see my IP when I query. They sky has not fallen.