diff --git a/ChangeLog.n b/ChangeLog.n
index bc7fea11c8c505a6c1a0564bd81f2261864a4717..52acd6df1c4eb69bd2f844930a417842ad177825 100644
--- a/ChangeLog.n
+++ b/ChangeLog.n
@@ -4,6 +4,11 @@ don't forget to change the version in utils/packages.lisp if you do anything
 user visible.
 
 *******************************************************************************
+2009-06-16  Andreas Fuchs  <afuchs@franz.com>
+
+	* silica/db-scroll.lisp: Fix a strange type error in scrolling that would crash on OS
+	  X with Motif 2.3 but not on other platforms.
+	
 2009-06-16  Andreas Fuchs  <afuchs@franz.com>
 	
 	* tk/xm-widgets.lisp: Fix the allocation of string lookup buffers for multibyte
diff --git a/silica/db-scroll.lisp b/silica/db-scroll.lisp
index 2df39cf098dff1d9a425ffe4023224171ffd34fb..d539c2dfba10e2457da524856bafd8a9d014d22a 100644
--- a/silica/db-scroll.lisp
+++ b/silica/db-scroll.lisp
@@ -292,7 +292,7 @@
               ;; Must go after bounding-rectangle-set-position
               (update-scroll-bars viewport)
               (if (medium-can-scroll-by-copy-region-p
-                   (sheet-medium medium)
+                   medium
                    (make-bounding-rectangle left top right bottom)
                    (pane-viewport-region sheet))
                   (progn