Works for me; but then I use "outdated" software: OpenBSD 3.8.
Are you sure your browser is asking for exactly that name, and not
some name in those domains you specified? For those cases I simply
add the domains with a wildcard to my local DNS server, e.g.,
named.conf:
zone "doubleclick.com" {
type master;
file "master/doubleclick.com";
};
master/doubleclick.com:
[[usual SOA]]
ad.doubleclick.com. IN A 127.0.0.1
*.doubleclick.com. IN A 127.0.0.1