diff -Nur Mail-SpamAssassin-3.4.1.orig/lib/Mail/SpamAssassin/DnsResolver.pm Mail-SpamAssassin-3.4.1/lib/Mail/SpamAssassin/DnsResolver.pm
--- Mail-SpamAssassin-3.4.1.orig/lib/Mail/SpamAssassin/DnsResolver.pm	2015-04-28 13:56:49.000000000 -0600
+++ Mail-SpamAssassin-3.4.1/lib/Mail/SpamAssassin/DnsResolver.pm	2016-06-11 13:55:15.380517343 -0600
@@ -592,6 +592,8 @@
   };
 
   if ($packet) {
+    # RD flag needs to be set explicitly since Net::DNS 1.01, Bug 7223	
+    $packet->header->rd(1);
   # my $udp_payload_size = $self->{res}->udppacketsize;
     my $udp_payload_size = $self->{conf}->{dns_options}->{edns};
     if ($udp_payload_size && $udp_payload_size > 512) {