* keymaps.texi (Tool Bar): Mention that Gtk+/NS ignores item 1 to 3.

doc/lispref/ChangeLog

+2013-11-10  Jan Djärv  <jan.h.d@swipnet.se>
+
+	* keymaps.texi (Tool Bar): Mention that Gtk+/NS ignores item 1 to 3.
+
 2013-11-09  Xue Fuqiao  <xfq.free@gmail.com>
 
 	* os.texi (Startup Summary): Add an index about startup screen.

doc/lispref/keymaps.texi

@@ -2631,6 +2631,9 @@ Used when the item is disabled and deselected.
 @end table
 @end table
 
+The GTK+ and NS versions of Emacs ignores items 1 to 3, because disabled and/or
+deselected images are autocomputed from item 0.
+
 If @var{image} is a single image specification, Emacs draws the tool bar
 button in disabled state by applying an edge-detection algorithm to the
 image.