diff --git a/ChangeLog b/ChangeLog
index 8089636bd4..c52281839c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Fri Jun 22 00:34:34 2007  Tim Janik  <timj@gtk.org>
+
+	* gdk/x11/gdkdisplay-x11.c (gdk_x11_display_get_xdisplay): applied
+	patch from Mark Tiefenbruck to add missing return_if_fail, #449862.
+
 2007-06-21  Matthias Clasen  <mclasen@redhat.com>
 
 	* gtk/gtktoolbar.c: Remove debug spew.  (#449492, Christian Persch)
diff --git a/gdk/x11/gdkdisplay-x11.c b/gdk/x11/gdkdisplay-x11.c
index de7c1f2f83..89aedfa3f2 100644
--- a/gdk/x11/gdkdisplay-x11.c
+++ b/gdk/x11/gdkdisplay-x11.c
@@ -896,6 +896,7 @@ _gdk_x11_display_screen_for_xrootwin (GdkDisplay *display,
 Display *
 gdk_x11_display_get_xdisplay (GdkDisplay *display)
 {
+  g_return_val_if_fail (GDK_IS_DISPLAY (display), NULL);
   return GDK_DISPLAY_X11 (display)->xdisplay;
 }