(focus-follows-mouse): Doc fix.

lisp/ChangeLog

+2002-02-25  Richard M. Stallman  <rms@gnu.org>
+
+	* frame.el (focus-follows-mouse): Doc fix.
+
 2002-02-26  Miles Bader  <miles@gnu.org>
 	* mwheel.el (mouse-wheel-mode): Pass vectors instead of symbols

lisp/frame.el

@@ -641,7 +641,10 @@ the user during startup."
 
 
 (defcustom focus-follows-mouse t
-  "*Non-nil if window system changes focus when you move the mouse."
+  "*Non-nil if window system changes focus when you move the mouse.
+You should set this variable to tell Emacs how your window manager
+handles focus, since there is no way in general for Emacs to find out
+automatically."
   :type 'boolean
   :group 'frames
   :version "20.3")