diff -Nru gnome-panel-2.30.2-orig/applets/wncklet/window-list.c gnome-panel-2.30.2/applets/wncklet/window-list.c
--- gnome-panel-2.30.2-orig/applets/wncklet/window-list.c	2010-06-22 18:27:02.000000000 +0100
+++ gnome-panel-2.30.2/applets/wncklet/window-list.c	2011-01-11 01:15:17.715682001 +0000
@@ -72,6 +72,7 @@
 static void
 tasklist_update (TasklistData *tasklist)
 {
+	wnck_tasklist_set_orientation(tasklist->tasklist, tasklist->orientation);
 	if (tasklist->orientation == GTK_ORIENTATION_HORIZONTAL) {
 		gtk_widget_set_size_request (GTK_WIDGET (tasklist->tasklist),
 					     -1, tasklist->size);