var cSubMenuVisible = 'none';

function showCSubMenu(id) {
	var item = document.getElementById(id);
	if(item.style.display == "none")
	{
		if(cSubMenuVisible != "none")
			cSubMenuVisible.style.display="none";
		item.style.display = '';
		cSubMenuVisible=item;
	}
	else
	{
		item.style.display = "none";
	}
}