diff --git a/dbus_wrapper_interface.h b/dbus_wrapper_interface.h
index b765600..568d4fa 100644
--- a/dbus_wrapper_interface.h
+++ b/dbus_wrapper_interface.h
@@ -48,6 +48,11 @@
                                  GError** error,
                                  GHashTable** out1) = 0;
 
+  virtual gboolean ProxyCall_0_1(DBusGProxy* proxy,
+                                 const char* method,
+                                 GError** error,
+                                 gint* out1) = 0;
+
   virtual gboolean ProxyCall_1_0(DBusGProxy* proxy,
                                  const char* method,
                                  GError** error,