var n = (document.layers) ? 1:0

if (document.images && n != 1)
{

	//home
	var homeoff = new Image();
	var homeroll = new Image();
	homeoff.src = 'gr/dmb_nav_home_off.gif'
	homeroll.src = 'gr/dmb_nav_home_on.gif'
	
	//cause
	var causeoff = new Image();
	var causeroll = new Image();
	causeoff.src = 'gr/dmb_nav_cause_off.gif'
	causeroll.src = 'gr/dmb_nav_cause_on.gif'

	//about
	var aboutoff = new Image();
	var aboutroll = new Image();
	aboutoff.src = 'gr/dmb_nav_about_off.gif'
	aboutroll.src = 'gr/dmb_nav_about_on.gif'
	
	//howto
	var howtooff = new Image();
	var howtoroll = new Image();
	howtooff.src = 'gr/dmb_nav_howto_off.gif'
	howtoroll.src = 'gr/dmb_nav_howto_on.gif'
	
}

function NavOver(imgnam)
{
	if (document.images && n != 1)
		{document.images[imgnam].src = eval(imgnam + 'roll.src');}
}

function NavOut(imgnam)
{
	if (document.images && n != 1)
		{document.images[imgnam].src = eval(imgnam + 'off.src');}
}