diff --git a/xep-0220.xml b/xep-0220.xml
index 9f5a82d6..ad4b0e93 100644
--- a/xep-0220.xml
+++ b/xep-0220.xml
@@ -527,7 +527,7 @@ receiver.target.tld.               86400 IN A                       10.44.0.4
     <p>The submission is as follows:</p>
     <code><![CDATA[
 <feature>
-  <ns>urn:xmpp:features:dialback</ns>
+  <ns>urn:xmpp:features:dialback:1</ns>
   <name>dialback</name>
   <element>dialback</element>
   <desc>Support for Server Dialback</desc>