diff --git a/Shorewall/tcrules b/Shorewall/tcrules
index 7162997ef..c0b96a01f 100644
--- a/Shorewall/tcrules
+++ b/Shorewall/tcrules
@@ -94,6 +94,9 @@
 #
 #			d) OR <mark>[/<mask>].
 #
+#			   Requires Extended MARK Target support in your kernel
+#			   and iptables.
+#
 #			   Logically or the <mark> value into the current
 #			   packet mark.
 #
@@ -101,6 +104,9 @@
 #
 #			d) AND <mark>[/<mask>].
 #
+#			   Requires Extended MARK Target support in your kernel
+#			   and iptables.
+#
 #			   Logically and the <mark> value with the current
 #			   packet mark.
 #