function HighlightPage(menuPage)
{
	var menu_item = document.getElementById (menuPage);
	menu_item.className = menuPage + '_on';
}

function UnHighlightPage(menuPage, current_button_id)
{
	var current_button = document.getElementById (current_button_id);
	var menu_item = document.getElementById (menuPage);
	if (menu_item != current_button)
	{
	menu_item.className = menuPage;
	}
}