diff --git a/smack-core/src/main/resources/org.jivesoftware.smack/smack-config.xml b/smack-core/src/main/resources/org.jivesoftware.smack/smack-config.xml
index fd4468b90..8ce5b7188 100644
--- a/smack-core/src/main/resources/org.jivesoftware.smack/smack-config.xml
+++ b/smack-core/src/main/resources/org.jivesoftware.smack/smack-config.xml
@@ -21,5 +21,6 @@
         <className>org.jivesoftware.smack.java7.Java7SmackInitializer</className>
         <className>org.jivesoftware.smack.im.SmackImInitializer</className>
         <className>org.jivesoftware.smackx.omemo.OmemoInitializer</className>
+        <className>org.jivesoftware.smackx.ox.OpenPgpInitializer</className>
     </optionalStartupClasses>
 </smack>