diff --git a/reference/classobj/functions/is-subclass-of.xml b/reference/classobj/functions/is-subclass-of.xml
index 945d06b059..37479aec03 100644
--- a/reference/classobj/functions/is-subclass-of.xml
+++ b/reference/classobj/functions/is-subclass-of.xml
@@ -76,6 +76,13 @@
Added allow_string parameter
+
+ 5.3.7
+
+ Added support for class_name to work with
+ intrefaces
+
+
5.0.3
@@ -141,6 +148,57 @@ if (is_subclass_of('WidgetFactory_Child', 'WidgetFactory')) {
yes, $WFC is a subclass of WidgetFactory
no, $WF is not a subclass of WidgetFactory
yes, WidgetFactory_Child is a subclass of WidgetFactory
+]]>
+
+
+
+
+
+ is_subclass_of using interface example
+
+
+]]>
+
+ &example.outputs;
+
+