//Rollover function for button feedback.
function changeImage(index)
{
	var myImages = new Array("images/blank.gif","images/home.gif","images/product.gif","images/cae.gif","images/mo.gif","images/fixer.gif","images/studies.gif","images/press.gif","images/consultancy.gif","images/training.gif","images/support.gif","images/events.gif","images/about.gif","images/order.gif","images/contact.gif");
	var myAltImages = new Array("images/alt_blank.gif","images/alt_home.gif","images/alt_product.gif","images/alt_cae.gif","images/alt_mo.gif","images/alt_fixer.gif","images/alt_studies.gif","images/alt_press.gif","images/alt_consultancy.gif","images/alt_training.gif","images/alt_support.gif","images/alt_events.gif","images/alt_about.gif","images/alt_order.gif","images/alt_contact.gif");
	//work out which images to change depending on browser
	var NN4 = document.layers? true : false;
	var IE = document.all? true : false;
	if (NN4)
	{
		for (i = 0; i < 5; i++)
		{
			var imageSrc = String(document.layers["Div1"].document.images[index].src);
			if (imageSrc.search("alt") == -1)
			{
				document.layers["Div1"].document.images[index].src = myAltImages[index];
			}
			else
			{
				document.layers["Div1"].document.images[index].src = myImages[index];
			}
		}
	}
	else if (IE)
	{
		for (i = 0; i <5; i++)
		{
			var imageSrc = String(document.images[index].src);
			if (imageSrc.search("alt") == -1)
			{
				document.images[index].src = myAltImages[index];
			}
			else
			{
				document.images[index].src = myImages[index];
			}
		}
	}
}