diff --git a/Shorewall/manpages/shorewall-mangle.xml b/Shorewall/manpages/shorewall-mangle.xml
index 30d6c8767..171d5af64 100644
--- a/Shorewall/manpages/shorewall-mangle.xml
+++ b/Shorewall/manpages/shorewall-mangle.xml
@@ -864,7 +864,7 @@ Normal-Service       =&gt; 0x00</programlisting>
                 on the firewall and whose source IP address matches one of the
                 listed addresses and does not match any address listed in the
                 <replaceable>exclusion</replaceable>. May not be used with a
-                chain qualifier (:P, :F, etc.) in the ACTION column. </para>
+                chain qualifier (:P, :F, etc.) in the ACTION column.</para>
               </listitem>
             </varlistentry>
 
@@ -1028,15 +1028,16 @@ Normal-Service       =&gt; 0x00</programlisting>
       <varlistentry>
         <term><emphasis role="bold">PROTO</emphasis> - {<emphasis
         role="bold">-</emphasis>|<emphasis
-        role="bold">{tcp:syn</emphasis>|<emphasis
+        role="bold">{tcp:[!]syn</emphasis>|<emphasis
         role="bold">ipp2p</emphasis>|<emphasis
         role="bold">ipp2p:udp</emphasis>|<emphasis
         role="bold">ipp2p:all</emphasis>|<emphasis>protocol-number</emphasis>|<emphasis>protocol-name</emphasis>|<emphasis
         role="bold">all}[,...]}</emphasis></term>
 
         <listitem>
-          <para>Protocol - <emphasis role="bold">ipp2p</emphasis> requires
-          ipp2p match support in your kernel and iptables.</para>
+          <para>See <ulink
+          url="shorewall-rules.html">shorewall-rules(5)</ulink> for
+          details.</para>
 
           <para>Beginning with Shorewall 4.5.12, this column can accept a
           comma-separated list of protocols.</para>
diff --git a/Shorewall/manpages/shorewall-secmarks.xml b/Shorewall/manpages/shorewall-secmarks.xml
index e20af98a5..89c35344d 100644
--- a/Shorewall/manpages/shorewall-secmarks.xml
+++ b/Shorewall/manpages/shorewall-secmarks.xml
@@ -229,8 +229,9 @@
         role="bold">all}[,...]</emphasis></term>
 
         <listitem>
-          <para>Protocol - <emphasis role="bold">ipp2p</emphasis> requires
-          ipp2p match support in your kernel and iptables.</para>
+          <para> See <ulink
+          url="shorewall-rules.html">shorewall-rules(5)</ulink> for
+          details.</para>
 
           <para>Beginning with Shorewall 4.5.12, this column can accept a
           comma-separated list of protocols.</para>
diff --git a/Shorewall/manpages/shorewall-snat.xml b/Shorewall/manpages/shorewall-snat.xml
index 5a94e15b1..16dd06047 100644
--- a/Shorewall/manpages/shorewall-snat.xml
+++ b/Shorewall/manpages/shorewall-snat.xml
@@ -256,8 +256,9 @@
 
         <listitem>
           <para>If you wish to restrict this entry to a particular protocol
-          then enter the protocol name (from protocols(5)) or number
-          here.</para>
+          then enter the protocol name (from protocols(5)) or number here. See
+          <ulink url="shorewall-rules.html">shorewall-rules(5)</ulink> for
+          details.</para>
 
           <para>Beginning with Shorewall 4.5.12, this column can accept a
           comma-separated list of protocols.</para>
diff --git a/Shorewall6/manpages/shorewall6-mangle.xml b/Shorewall6/manpages/shorewall6-mangle.xml
index 275a6a8bc..87c2e45fa 100644
--- a/Shorewall6/manpages/shorewall6-mangle.xml
+++ b/Shorewall6/manpages/shorewall6-mangle.xml
@@ -1026,8 +1026,9 @@ Normal-Service       =&gt; 0x00</programlisting>
         role="bold">all}[,...]}</emphasis></term>
 
         <listitem>
-          <para>Protocol - <emphasis role="bold">ipp2p</emphasis> requires
-          ipp2p match support in your kernel and iptables.</para>
+          <para>See <ulink
+          url="shorewall-rules.html">shorewall6-rules(5)</ulink> for
+          details.</para>
 
           <para>Beginning with Shorewall 4.5.12, this column can accept a
           comma-separated list of protocols.</para>
diff --git a/Shorewall6/manpages/shorewall6-secmarks.xml b/Shorewall6/manpages/shorewall6-secmarks.xml
index d176ab72e..a83c5773c 100644
--- a/Shorewall6/manpages/shorewall6-secmarks.xml
+++ b/Shorewall6/manpages/shorewall6-secmarks.xml
@@ -222,8 +222,9 @@
         role="bold">all}</emphasis></term>
 
         <listitem>
-          <para>Protocol - <emphasis role="bold">ipp2p</emphasis> requires
-          ipp2p match support in your kernel and iptables.</para>
+          <para>See <ulink
+          url="shorewall-rules.html">shorewall6-rules(5)</ulink> for
+          details.</para>
 
           <para>Beginning with Shorewall 4.5.12, this column can accept a
           comma-separated list of protocols.</para>
diff --git a/Shorewall6/manpages/shorewall6-snat.xml b/Shorewall6/manpages/shorewall6-snat.xml
index 44550ef4e..9d9c65d71 100644
--- a/Shorewall6/manpages/shorewall6-snat.xml
+++ b/Shorewall6/manpages/shorewall6-snat.xml
@@ -234,8 +234,9 @@
 
         <listitem>
           <para>If you wish to restrict this entry to a particular protocol
-          then enter the protocol name (from protocols(5)) or number
-          here.</para>
+          then enter the protocol name (from protocols(5)) or number here. See
+          <ulink url="shorewall-rules.html">shorewall6-rules(5)</ulink> for
+          details.</para>
 
           <para>Beginning with Shorewall 4.5.12, this column can accept a
           comma-separated list of protocols.</para>