diff --git a/en_US.ISO8859-1/books/handbook/firewalls/chapter.sgml b/en_US.ISO8859-1/books/handbook/firewalls/chapter.sgml
index 1fdee36923..af7d378a50 100644
--- a/en_US.ISO8859-1/books/handbook/firewalls/chapter.sgml
+++ b/en_US.ISO8859-1/books/handbook/firewalls/chapter.sgml
@@ -1686,7 +1686,7 @@ block in log first quick on dc0 all
         role="ipaddr">192.168.1.0/24</hostid>.</para>
 
       <para>The <replaceable>PUBLIC_ADDRESS</replaceable> can either
-        be the external IP address or the special keyword `0.32',
+        be the external IP address or the special keyword <literal>0/32</literal>,
         which means to use the IP address assigned to
         <replaceable>IF</replaceable>.</para>
     </sect2>
@@ -1706,7 +1706,7 @@ block in log first quick on dc0 all
         range specified to the left of the arrow symbol on the
         <acronym>NAT</acronym> rule. On a match the packet has its
         source IP address rewritten with the public IP address
-        obtained by the `0.32' keyword. <acronym>NAT</acronym> posts a
+        obtained by the <literal>0/32</literal> keyword. <acronym>NAT</acronym> posts a
         entry in its internal <acronym>NAT</acronym> table so when the
         packet returns from the public Internet it can be mapped back
         to its original private IP address and then passed to the
@@ -1753,7 +1753,7 @@ block in log first quick on dc0 all
              with a <programlisting> tag ?-->
         <para>A normal NAT rule would look like:</para>
 
-        <programlisting>map dc0 192.168.1.0/24 -> 0.32</programlisting>
+        <programlisting>map dc0 192.168.1.0/24 -> 0/32</programlisting>
 
         <para>In the above rule the packet's source port is unchanged
           as the packet passes through IP<acronym>NAT</acronym>. By
@@ -1763,13 +1763,13 @@ block in log first quick on dc0 all
           IP<acronym>NAT</acronym> to modify the source port to be
           within that range:</para>
 
-        <programlisting>map dc0 192.168.1.0/24 -> 0.32 portmap tcp/udp 20000:60000</programlisting>
+        <programlisting>map dc0 192.168.1.0/24 -> 0/32 portmap tcp/udp 20000:60000</programlisting>
 
         <para>Additionally we can make things even easier by using the
           <literal>auto</literal> keyword to tell IP<acronym>NAT</acronym> to determine
           by itself which ports are available to use:</para>
 
-        <programlisting>map dc0 192.168.1.0/24 -> 0.32 portmap tcp/udp auto</programlisting>
+        <programlisting>map dc0 192.168.1.0/24 -> 0/32 portmap tcp/udp auto</programlisting>
       </sect3>
 
       <sect3>