var DOM = (document.getElementById) ? true : false;
var NS4 = (document.layers) ? true : false;
var IE4 = (document.all) ? true : false;
var rollLock = false;

function rollNav2()
{
	if (rollLock)
		return;

	if (DOM)
		document.getElementById('nav2').style.visibility = 'visible';
	else if (NS4)
		document.layers['nav2'].visibility = 'visible';
	else if (IE4)
		document.all['nav2'].style.visibility = 'visible';

	rollLock = true;
	return;
}