diff --git a/reference/pcre/pattern.syntax.xml b/reference/pcre/pattern.syntax.xml
index 88f81ddc5d..12ddffa130 100644
--- a/reference/pcre/pattern.syntax.xml
+++ b/reference/pcre/pattern.syntax.xml
@@ -39,10 +39,12 @@
       following are all examples of valid delimited patterns.
       <informalexample>
        <programlisting>
-         /foo bar/
-         #^[^0-9]$#
-         +php+
-         %[a-zA-Z0-9_-]%
+<![CDATA[
+/foo bar/
+#^[^0-9]$#
++php+
+%[a-zA-Z0-9_-]%
+]]>
        </programlisting>
       </informalexample>
      </para>
@@ -53,8 +55,10 @@
       readability.
       <informalexample>
        <programlisting>
-        /http:\/\//
-        #http://#
+<![CDATA[
+/http:\/\//
+#http://#
+]]>
        </programlisting>
       </informalexample>
       The <function>preg_quote</function> function may be used to escape a string
@@ -67,7 +71,9 @@
       starting and ending delimiter, respectively.
       <informalexample>
        <programlisting>
-        {this is a pattern}
+<![CDATA[
+{this is a pattern}
+]]>
        </programlisting>
       </informalexample>
      </para>
@@ -77,7 +83,9 @@
       of case-insensitive matching:
       <informalexample>
        <programlisting>
-        #[a-z]#i
+<![CDATA[
+#[a-z]#i
+]]>
        </programlisting>
       </informalexample>
      </para>