tokenize 46 $7
var %dronebl.ip $+($4,.,$3,.,$2,.,$1,.dnsbl.dronebl.org)

Also, you seem to be z:lining the saved address after /dns. That's probably a bad idea because:

1. If you get another /dns response before the one you want, you'll z:line the address regardless of whether it's a proxy.
2. If you do a /dns without having the variable set, you'll z:line @ which should go to @* and ban everyone on the network.

You should check that the variable is equal to the DNS returned with $dns(N).ip