diff --git a/manpages/shorewall-accounting.xml b/manpages/shorewall-accounting.xml
index 0edb19a2d..078531f9f 100644
--- a/manpages/shorewall-accounting.xml
+++ b/manpages/shorewall-accounting.xml
@@ -287,7 +287,8 @@
 
               <listitem>
                 <para>Designates a connection mark. If omitted, the packet
-                mark's value is tested.</para>
+                mark's value is tested. This option is only supported by
+                Shorewall-perl.</para>
               </listitem>
             </varlistentry>
           </variablelist>
diff --git a/manpages/shorewall-masq.xml b/manpages/shorewall-masq.xml
index 780510b51..dccd0a49e 100644
--- a/manpages/shorewall-masq.xml
+++ b/manpages/shorewall-masq.xml
@@ -345,7 +345,8 @@
 
               <listitem>
                 <para>Designates a connection mark. If omitted, the packet
-                mark's value is tested.</para>
+                mark's value is tested. This option is only supported by
+                Shorewall-perl.</para>
               </listitem>
             </varlistentry>
           </variablelist>
diff --git a/manpages/shorewall-rules.xml b/manpages/shorewall-rules.xml
index f7a9cfbc0..138c82f6d 100644
--- a/manpages/shorewall-rules.xml
+++ b/manpages/shorewall-rules.xml
@@ -934,7 +934,8 @@
 
               <listitem>
                 <para>Designates a connection mark. If omitted, the packet
-                mark's value is tested.</para>
+                mark's value is tested. This option is only supported by
+                Shorewall-perl.</para>
               </listitem>
             </varlistentry>
           </variablelist>
diff --git a/manpages/shorewall-tos.xml b/manpages/shorewall-tos.xml
index a8471e112..764411ba0 100644
--- a/manpages/shorewall-tos.xml
+++ b/manpages/shorewall-tos.xml
@@ -185,7 +185,8 @@
 
               <listitem>
                 <para>Designates a connection mark. If omitted, the packet
-                mark's value is tested.</para>
+                mark's value is tested. This option is only supported by
+                Shorewall-perl.</para>
               </listitem>
             </varlistentry>
           </variablelist>