Why no "query-tooltip" signal with AppIndicator?

ai-test.c

#include <gtk/gtk.h>
#include <libappindicator/app-indicator.h>


static void on_status_icon_activate(GtkStatusIcon *status_icon, GtkMenu *menu)
{
	gtk_menu_popup(menu, NULL, NULL, gtk_status_icon_position_menu, status_icon,
		0, gtk_get_current_event_time());
}


static gboolean on_menu_item_query_tooltip(GtkWidget *widget, gint x, gint y,
	gboolean keyboard_mode, GtkTooltip *tooltip, gpointer user_data)

{
	g_print("Received query-tooltip from widget '%s' @ %d x %d\n",
		gtk_widget_get_name(widget), x, y);
	return TRUE;
}


static GtkWidget *create_menu(void)
{
	GtkWidget *menu, *item;

	menu = gtk_menu_new();

	item = gtk_menu_item_new_with_label("Test Item");
	gtk_widget_set_name(item, "aiTestItem");
	gtk_widget_set_has_tooltip(item, TRUE);
	g_signal_connect(item, "query-tooltip", G_CALLBACK(on_menu_item_query_tooltip), NULL);
	gtk_menu_append(GTK_MENU(menu), item);

	item = gtk_menu_item_new_with_label("Quit");
	g_signal_connect(item, "activate", G_CALLBACK(gtk_main_quit), NULL);
	gtk_menu_append(GTK_MENU(menu), item);

	gtk_widget_show_all(menu);

	return menu;
}


static void create_appindic_icon(void)
{
	GtkWidget *menu;
	AppIndicator *indic;
	indic = app_indicator_new("aitest", "camera-video", APP_INDICATOR_CATEGORY_HARDWARE);
	menu = create_menu();
	app_indicator_set_menu(indic, GTK_MENU(menu));
	app_indicator_set_status(indic, APP_INDICATOR_STATUS_ACTIVE);
}


static void create_status_icon(void)
{
	GtkWidget *menu;
	GtkStatusIcon *stat;
	stat = gtk_status_icon_new_from_icon_name("camera-video");
	menu = create_menu();
	g_signal_connect(stat, "activate", G_CALLBACK(on_status_icon_activate), menu);
}


int main(int argc, char *argv[])
{

	gtk_init(&argc, &argv);

	create_appindic_icon();
	create_status_icon();

	gtk_main();

	return 0;

}

Makefile:

ai-test: ai-test.c
    gcc -g -Wall `pkg-config --cflags --libs gtk+-2.0 appindicator-0.1` -o $@ $^

clean:
    rm -f ai-test