diff --git a/include/piano_roll.h b/include/piano_roll.h
index 6a6ca847c..04763b610 100644
--- a/include/piano_roll.h
+++ b/include/piano_roll.h
@@ -109,6 +109,7 @@ protected:
 	virtual void paintEvent( QPaintEvent * _pe );
 	virtual void resizeEvent( QResizeEvent * _re );
 	virtual void wheelEvent( QWheelEvent * _we );
+	virtual bool x11Event( XEvent * _xe );
 
 	int FASTCALL getKey( int _y );
 	static inline void drawNoteRect( QPainter & _p, Uint16 _x, Uint16 _y,