(Qlanguage_change) [MAC_OS]: New variable.

(syms_of_keyboard) [MAC_OS]: Intern and staticpro it.
(kbd_buffer_get_event) [MAC_OS]: Make event for	LANGUAGE_CHANGE_EVENT.

src/keyboard.c

@@ -530,7 +530,7 @@ Lisp_Object Qmouse_fixup_help_message;
 /* Symbols to denote kinds of events.  */
 Lisp_Object Qfunction_key;
 Lisp_Object Qmouse_click;
-#ifdef WINDOWSNT
+#if defined (WINDOWSNT) || defined (MAC_OS)
 Lisp_Object Qlanguage_change;
 #endif
 Lisp_Object Qdrag_n_drop;
@@ -4036,11 +4036,16 @@ kbd_buffer_get_event (kbp, used_mouse_menu)
 	    x_activate_menubar (XFRAME (event->frame_or_window));
 	}
 #endif
-#ifdef WINDOWSNT
+#if defined (WINDOWSNT) || defined (MAC_OS)
       else if (event->kind == LANGUAGE_CHANGE_EVENT)
 	{
+#ifdef MAC_OS
+	  /* Make an event (language-change (KEY_SCRIPT)).  */
+	  obj = Fcons (make_number (event->code), Qnil);
+#else
 	  /* Make an event (language-change (FRAME CHARSET LCID)).  */
 	  obj = Fcons (event->frame_or_window, Qnil);
+#endif
 	  obj = Fcons (Qlanguage_change, Fcons (obj, Qnil));
 	  kbd_fetch_ptr = event + 1;
 	}
@@ -10845,7 +10850,7 @@ syms_of_keyboard ()
   staticpro (&Qfunction_key);
   Qmouse_click = intern ("mouse-click");
   staticpro (&Qmouse_click);
-#ifdef WINDOWSNT
+#if defined (WINDOWSNT) || defined (MAC_OS)
   Qlanguage_change = intern ("language-change");
   staticpro (&Qlanguage_change);
 #endif