diff --git a/appendices/ini.xml b/appendices/ini.xml
index 87dd1b3434..d57bba536b 100644
--- a/appendices/ini.xml
+++ b/appendices/ini.xml
@@ -3909,16 +3909,21 @@ auto_prepend_file=security.php
        <type>string</type>
       </term>
       <listitem>
-       <simpara>
+       <para>
         This directive allows you to disable certain functions for 
         <link linkend="security">security</link> reasons. It takes 
         on a comma-delimited list of function names. disable_functions
         is not affected by <link linkend="ini.safe-mode">Safe Mode</link>.
-       </simpara>
-       <simpara>
+       </para>
+       <para>
+        Only <link linkend="functions.internal">internal functions</link> can
+        be disabled using this directive. <link linkend="functions.user-defined">User-defined functions</link>
+        are unaffected.
+       </para>
+       <para>
         This directive must be set in &php.ini; For example, you 
         cannot set this in &httpd.conf;.
-       </simpara>
+       </para>
       </listitem>
      </varlistentry>