diff --git a/gtk2_ardour/midi_port_dialog.cc b/gtk2_ardour/midi_port_dialog.cc
index f4c7e5a26b..837bf164b3 100644
--- a/gtk2_ardour/midi_port_dialog.cc
+++ b/gtk2_ardour/midi_port_dialog.cc
@@ -59,8 +59,8 @@ MidiPortDialog::MidiPortDialog ()
 
 	port_name.signal_activate().connect (sigc::mem_fun (*this, &MidiPortDialog::entry_activated));
 
-	add_button (Stock::CANCEL, RESPONSE_CANCEL);
-	add_button (Stock::ADD, RESPONSE_ACCEPT);
+	add_button ("CANCEL", RESPONSE_CANCEL);
+	add_button ("ADD", RESPONSE_ACCEPT);
 
 	show_all_children ();
 }