// preload images
	
	var offImages = new Array();

	offImages["products"] 	= "images/n1_products_off.gif";
	offImages["customers"] 		= "images/n1_customers_off.gif";
	offImages["partners"] 		= "images/n1_partners_off.gif";
	offImages["contact"] 		= "images/n1_contact_off.gif";
	offImages["news"] 	= "images/n1_news_off.gif";
	
	
	var ovrImages = new Array();
	
	ovrImages["products"] 	= "images/n1_products_on.gif";
	ovrImages["customers"] 		= "images/n1_customers_on.gif";
	ovrImages["partners"] 		= "images/n1_partners_on.gif";
	ovrImages["contact"] 		= "images/n1_contact_on.gif";
	ovrImages["news"] 	= "images/n1_news_on.gif";

		
	function swap(image) {
		docImage = eval("document." + image);
		imageSrc = docImage.src;
		if (imageSrc.indexOf("off") != -1) {
			docImage.src = ovrImages[image];
		}
		else if (imageSrc.indexOf("ovr") != -1) {
			docImage.src = offImages[image];
		}
		else {
			docImage.src = offImages[image];
		}
	}