(Button Types): For define-button-type, clarify type of NAME.

doc/lispref/ChangeLog

+2008-01-27  Thien-Thi Nguyen  <ttn@gnuvola.org>
+
+	* display.texi (Button Types):
+	For define-button-type, clarify type of NAME.
+
 2008-01-19  Martin Rudalics  <rudalics@gmx.at>
 
 	* buffers.texi (Buffer Modification): Fix typo.

doc/lispref/display.texi

@@ -4499,7 +4499,8 @@ so that it's easy to define special-purpose types of buttons for
 specific tasks.
 
 @defun define-button-type name &rest properties
-Define a `button type' called @var{name}.  The remaining arguments
+Define a `button type' called @var{name} (a symbol).
+The remaining arguments
 form a sequence of @var{property value} pairs, specifying default
 property values for buttons with this type (a button's type may be set
 by giving it a @code{type} property when creating the button, using