diff --git a/Shorewall-perl/Shorewall/Interfaces.pm b/Shorewall-perl/Shorewall/Interfaces.pm
index 374957db9..f4be3d8e1 100644
--- a/Shorewall-perl/Shorewall/Interfaces.pm
+++ b/Shorewall-perl/Shorewall/Interfaces.pm
@@ -42,6 +42,7 @@ our @EXPORT = qw( add_group_to_zone
 		  interface_is_optional
 		  find_interfaces_by_option
 		  get_interface_option
+		  clear_interface_option
 
 		  @interfaces  );
 our @EXPORT_OK = ();
@@ -435,4 +436,13 @@ sub get_interface_option( $$ ) {
     $interfaces{$interface}{options}{$option};
 }
 
+#
+# Clear an option for an interface
+#
+sub clear_interface_option( $$ ) {
+    my ( $interface, $option ) = @_;
+
+    delete $interfaces{$interface}{options}{$option};
+}
+
 1;
diff --git a/Shorewall-perl/Shorewall/Rules.pm b/Shorewall-perl/Shorewall/Rules.pm
index df7396380..4e35e314f 100644
--- a/Shorewall-perl/Shorewall/Rules.pm
+++ b/Shorewall-perl/Shorewall/Rules.pm
@@ -714,7 +714,14 @@ sub setup_mac_lists( $ ) {
 
 		fatal_error "Invalid DISPOSITION ( $disposition)" if ( $table eq 'mangle' ) && ! $targetref->{mangle};
 
-		fatal_error "No hosts on $interface have the maclist option specified" unless $maclist_interfaces{$interface};
+		unless ( $maclist_interfaces{$interface} ) {
+		    if ( get_interface_option( $interface, 'optional' ) && get_interface_option( $interface, 'detectnets' ) ) {
+			clear_interface_option( $interface, 'maclist' );
+			next;
+		    } 
+		
+		    fatal_error "No hosts on $interface have the maclist option specified";
+		}
 
 		my $chainref = $chain_table{$table}{( $ttl ? macrecent_target $interface : mac_chain $interface )};