diff --git a/documentation/ref-manual/introduction.xml b/documentation/ref-manual/introduction.xml
index 9e2bb9fd8f..c28adea1d8 100644
--- a/documentation/ref-manual/introduction.xml
+++ b/documentation/ref-manual/introduction.xml
@@ -216,8 +216,8 @@
                 <listitem><para>Fedora release 20 (Heisenbug)</para></listitem> -->
                 <listitem><para>Fedora release 22</para></listitem>
                 <listitem><para>Fedora release 23</para></listitem>
-                <listitem><para>Fedora release 24</para></listitem>
-<!--                <listitem><para>CentOS release 5.6 (Final)</para></listitem>
+<!--                <listitem><para>Fedora release 24</para></listitem>
+                <listitem><para>CentOS release 5.6 (Final)</para></listitem>
                 <listitem><para>CentOS release 5.7 (Final)</para></listitem>
                 <listitem><para>CentOS release 5.8 (Final)</para></listitem>
                 <listitem><para>CentOS release 6.3 (Final)</para></listitem>