1 files changed, 11 insertions, 0 deletions
diff --git a/ext/tk/lib/tkextlib/bwidget/messagedlg.rb b/ext/tk/lib/tkextlib/bwidget/messagedlg.rb
index d7b2bbc32b..9c946d0630 100644
--- a/ext/tk/lib/tkextlib/bwidget/messagedlg.rb
+++ b/ext/tk/lib/tkextlib/bwidget/messagedlg.rb
@@ -5,6 +5,7 @@
 
 require 'tk'
 require 'tkextlib/bwidget.rb'
+require 'tkextlib/bwidget/dialog.rb'
 
 module Tk
   module BWidget
@@ -43,6 +44,16 @@ class Tk::BWidget::MessageDlg
   end
   private :create_self
 
+  def __strval_optkeys
+    super() << 'message' << 'title'
+  end
+  private :__strval_optkeys
+
+  def __listval_optkeys
+    super() << 'buttons'
+  end
+  private :__listval_optkeys
+
   def cget(slot)
     slot = slot.to_s
     if slot == 'relative'