default_zone = calendar_config_get_icaltimezone ();
	tmp1 = icaltimezone_get_display_name(default_zone);
	//tmp = icaltimezone_get_display_name (zone);
	if(zone == NULL)
	{
		tmp = icaltimezone_get_location(zone);
		tmp2 = g_strdup_printf(_("Timezone: %s %s"), tmp , tmp1);
		hbox = gtk_hbox_new (FALSE, 0);
		gtk_box_pack_start ((GtkBox *)hbox, gtk_label_new_with_mnemonic (tmp2), FALSE, FALSE, 0);
		ebox = gtk_event_box_new ();
		gtk_container_add ((GtkContainer *)ebox, hbox);
		gtk_box_pack_start ((GtkBox *)box, ebox, FALSE, FALSE, 0);
	
		g_free (tmp);
		g_free (tmp2);
	}
	g_free(tmp1);


==============This code displayed tooltip displaying default time zone and null, if zone is not Null, it wud not display default time zone ======