User-agent: Mozilla Thunderbird 0.7.1 (X11/20040626)
You are hurting the Tor network more than you realize. You are lying to
clients and clients cache that answer. Don't do this.
I've tested this before, and since the /etc/hosts entry refers to an
address which is blocked by *all* TOR servers default exit policy, it
just says "requested exit node will deny your request".
Do they still cache the DNS answer?
Would it be better to block them by allowing a (legitimate) DNS lookup,
and then null-routing the IP space involved?