var home_on = new Image();
var home_off = new Image();
var productinfo_on = new Image();
var productinfo_off = new Image();
var products_on = new Image();
var products_off = new Image();
var samples_on = new Image();
var samples_off = new Image();
var pricelist_on = new Image();
var pricelist_off = new Image();
var buybuybuy_on = new Image();
var buybuybuy_off = new Image();
var contactus_on = new Image();
var contactus_off = new Image();
var customercomments_on = new Image();
var customercomments_off = new Image();

function preLoadImages() {
//if (document.images) {//if browser allows, preload images
 home_on.src="home_button.gif";
 home_off.src="home_off_button.gif";
 productinfo_on.src="productinfo_button.gif";
 productinfo_off.src="productinfo_off_button.gif";
 products_on.src="products_button.gif";
 products_off.src="products_off_button.gif";
 samples_on.src="samples_button.gif";
 samples_off.src="samples_off_button.gif";
 pricelist_on.src="pricelist_button.gif";
 pricelist_off.src="pricelist_off_button.gif";
 buybuybuy_on.src="buybuybuy_button.gif";
 buybuybuy_off.src="buybuybuy_off_button.gif";
 contactus_on.src="contactus_button.gif";
 contactus_off.src="contactus_off_button.gif";
 customercomments_on.src="customercomments_button.gif";
 customercomments_off.src="customercomments_off_button.gif";



//}
}

function swapImgRestore( img ) { //swap in highlighted images
      imga = eval(img + "_on.src");
      if ( (document.images) && (imga)) {
            document.images[img].src = eval( img + "_on.src");
      } 
} 

function swapImage( img ) { //swap in unhighlighted images
      imgb = eval(img + "_off.src");
      if ( (document.images) && (imgb)) {
            document.images[img].src = eval( img + "_off.src");
      } 
}