var curImg;
var curImgTxt;

function preloadImages() {
	var loadedImages = new Array;
	for(i=0; i < preloadImages.arguments.length; i++) {
		loadedImages[i] = new Image();
		loadedImages[i].src = "images/"+preloadImages.arguments[i];
	}
}

function swapImage(targetImage, newImageSrc) {
	if(document.images) {
		if(targetImage && targetImage.src)
			targetImage.src = newImageSrc;
	}
}

function setCurImg(newImg, newImgTxt) {
	swapImage(curImg, "images/" + curImgTxt + "_on.jpg");
	curImg = newImg;
	curImgTxt = newImgTxt;
}

preloadImages("top_nav_about_us_click.gif", "top_nav_about_us_clickb.gif", "top_nav_services_click.gif", "top_nav_services_click.gif", "top_nav_projects_click.gif",  "top_nav_faqs_click.gif", "top_nav_careers_click.gif", "top_nav_contact_click.gif");