for (i = 0; i < 7; i++) {
	new Image().src = "/include/images/navigation_" + i + "_default.png";
	new Image().src = "/include/images/navigation_" + i + "_highlight.png";
}

function highlight(number, highlight)
{
	if (highlight) {
		document.getElementsByName("navigation_image")[number].src = "/include/images/navigation_" + number + "_highlight.png";
	} else {
		document.getElementsByName("navigation_image")[number].src = "/include/images/navigation_" + number + "_default.png";
	}
}