Check IPv6 addresses at dnswl.org and Spamhaus whitelist

conf/modules.conf

@@ -119,6 +119,7 @@ rbl {
     spamhaus_swl {
         symbol = "RWL_SPAMHAUS_WL";
         rbl = "swl.spamhaus.org";
+        ipv6 = true;
         returncodes {
             RWL_SPAMHAUS_WL_IND = "127.0.2.2";
             RWL_SPAMHAUS_WL_TRANS = "127.0.2.3";
@@ -191,6 +192,7 @@ rbl {
     dnswl {
         symbol = "RCVD_IN_DNSWL";
         rbl = "list.dnswl.org";
+        ipv6 = true;
         returncodes {
             RCVD_IN_DNSWL_NONE = "127.0.%d+.0";
             RCVD_IN_DNSWL_LOW = "127.0.%d+.1";