function isDefined(property) {
  return (typeof property != 'undefined');
}

var rolloverInitialized = false;

function rolloverInit() {
  if (!rolloverInitialized && isDefined(document.images)) {
     var bodyId = document.body.id;    // ID of the BODY tag
     
     // get all images (including all <input type="image">s)
     // use getElementsByTagName() if supported
     var images = new Array();
     
     if (isDefined(document.getElementsByTagName)) {
        images = document.getElementsByTagName('img');
        var inputs = document.getElementsByTagName('input');
        
        for (var i = 0; i < inputs.length; i++) {
           if (inputs[i].type == 'image') {
              images[images.length] = inputs[i];
           }
        }
     }

     // get all images with '_off.' in src value excepting the one that is for the BODY
     for (var i = 0; i < images.length; i++) {
        if (images[i].src.indexOf('_off.') != -1) {

           // check for BODY image, and turn it 'on' if found
           //if (images[i].src.indexOf(bodyId) != -1) {
        		//images[i].src = images[i].src.replace(/_off\./, '_on.');
           //} else {
	           var image = images[i];
				
	           // store the off state filename in a property of the image object
	           image.offImage = new Image();
	           image.offImage.src = image.src;
				
	           // store the on state filename in a property of the image object
	           // (also preloads the on state image)
	           image.onImage = new Image();
	           image.onImage.imageElement = image;
				
	           // add onmouseover and onmouseout event handlers once the on state image has loaded
	           // Safari's onload is screwed up for off-screen images; temporary fix
	           if (navigator.userAgent.toLowerCase().indexOf('safari') != - 1) {
	              image.onmouseover = function() {
	                 this.src = this.onImage.src;
	              };
	              image.onmouseout = function() {
	                 this.src = this.offImage.src;
	              };
	           } else {
	              image.onImage.onload = function() {
	                 this.imageElement.onmouseover = function() {
	                    this.src = this.onImage.src;
	                 };
	                 this.imageElement.onmouseout = function() {
	                    this.src = this.offImage.src;
	                 };
	              };
	           }
				
	           // set src of on state image after defining onload event handler
	           // so cached images (that load instantly in IE) will trigger onload
	           image.onImage.src = image.src.replace(/_off\./, '_on.');
			
          //}
        }
     }
  }
  
  rolloverInitialized = true;
}

// call rolloverInit when document finishes loading
if (isDefined(window.addEventListener)) {
   window.addEventListener('load', rolloverInit, false);
} else if (isDefined(window.attachEvent)) {
   window.attachEvent('onload', rolloverInit);
}