diff --git a/src/config/kbdbind.c b/src/config/kbdbind.c
index eaf89059..378ba8fa 100644
--- a/src/config/kbdbind.c
+++ b/src/config/kbdbind.c
@@ -108,7 +108,7 @@ free_keybinding(struct keybinding *keybinding)
 	}
 
 #ifdef CONFIG_SCRIPTING
-/* TODO: unref function must be implemented. */
+/* TODO: unref function must be implemented. This is part of bug 810. */
 /*	if (keybinding->event != EVENT_NONE)
 		scripting_unref(keybinding->event); */
 #endif
diff --git a/src/main/event.h b/src/main/event.h
index 3ee7a03b..145b95a3 100644
--- a/src/main/event.h
+++ b/src/main/event.h
@@ -60,7 +60,8 @@ int register_event(unsigned char *name);
 
 /* This unregisters an event number @event, freeing the resources it
  * occupied, chain of associated hooks and unallocating the event id for
- * further recyclation. */
+ * further recyclation.
+ * Bug 810: unregister_event has not yet been implemented. */
 int unregister_event(int event);
 
 int register_event_hook(int id, event_hook_T callback, int priority, void *data);
diff --git a/src/scripting/lua/core.c b/src/scripting/lua/core.c
index 432581ec..59f62709 100644
--- a/src/scripting/lua/core.c
+++ b/src/scripting/lua/core.c
@@ -268,6 +268,7 @@ run_lua_func(va_list ap, void *data)
 	return EVENT_HOOK_STATUS_NEXT;
 }
 
+/* bind_key (keymap, keystroke, function) */
 static int
 l_bind_key(LS)
 {
@@ -284,6 +285,16 @@ l_bind_key(LS)
 
 	if (!init_string(&event_name)) goto lua_error;
 
+	/* ELinks will need to call the Lua function when the user
+	 * presses the key.  However, ELinks cannot store a pointer
+	 * to the function, because the C API of Lua does not provide
+	 * one.  Instead, ask the "reference system" of Lua to
+	 * generate an integer key that ELinks can store.
+	 *
+	 * TODO: If l_bind_key() succeeds, then the function will
+	 * never be removed from the reference system again, because
+	 * the rest of ELinks does not tell this module if the
+	 * keybinding is removed.  This is part of bug 810.  */
 	lua_pushvalue(S, 3);
 	ref = luaL_ref(S, LUA_REGISTRYINDEX);
 	add_format_to_string(&event_name, "lua-run-func %i", ref);