diff --git a/contrib/x11/xlib.factor b/contrib/x11/xlib.factor
index 88bbf3b075..4f1b33f66e 100644
--- a/contrib/x11/xlib.factor
+++ b/contrib/x11/xlib.factor
@@ -1146,6 +1146,20 @@ BEGIN-STRUCT: XVisualInfo
 	FIELD: int bits_per_rgb
 END-STRUCT
 
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+! Appendix D - Compatibility Functions
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+FUNCTION: Status XSetStandardProperties (
+	Display* display,
+	Window w,
+	char* window_name,
+	char* icon_name,
+	Pixmap icon_pixmap,
+	char** argv,
+	int argc,
+	XSizeHints* hints ) ;
+
 ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 
 : CurrentTime 0 ;