var randomnumber = (Math.floor(Math.random()*3) + 1);

function setHeaderImage()
{
	var strPageName = new String(window.location);
	if (strPageName.indexOf("index.asp")>=0)
	{
		strImagePath = "<img src='/images/main_image_index.jpg' border='0'/>";
	} else {
		strImagePath = "<img src='/images/main_image_0" + randomnumber + ".jpg' border='0'/>";
	}
	document.write(strImagePath);
}