function preloadImages() {

if(document.images) {
    var image_array = new Array();
    
    // path to the directory with images
    var path = 'http://www.smscodes.net/images/images/buttons/';
 
    // enumeration of the "rollover" images
    image_array[0] = path + "1mydetails-over.gif";
    image_array[1] = path + "2setup-over.gif";
    image_array[2] = path + "3history-over.gif";
    image_array[3] = path + "4help-over.gif";
    image_array[4] = path + "5upgrade-over.gif";

    image_array[5] = path + "moreinfo-over.gif";
    image_array[6] = path + "howtouse-over.gif";
    image_array[7] = path + "purchase-over.gif";
    image_array[8] = path + "faq-over.gif";
  
    var preload_image = new Array ();
   
    for(var i=0; i<image_array.length; i++) {
        preload_image[i]= new Image();
        preload_image[i].src = image_array[i]; 
        }

    }

} 

function rollover(name, filename)
{
  var fullpath = 'http://www.smscodes.net/images/buttons/' + filename;
  document.images[name].src = fullpath;
}