Проблема со сменой изображений при наведение

<script type="text/javascript" src="./jquery-1.4.2.min.js"></script>
<script type="text/javascript">
//On Doc Ready
$(function() {
   //*************** JQeury Universal Image Button ***************
   function getHoverPath (imgPath) {
      //split imgPath after each '/' and create array to path directories and file name
      var srcPathArray = imgPath.split('/');
      //find image file name get length of srcPathArray and retrieve last item which is the image file ex: "images/buttons/IMG.gif"
      var imgFile = srcPathArray[srcPathArray.length-1];
      //image file name array split at "." to get:[fileName, ext]
      var imgArray = imgFile.split('.');
      //img name (first item in imgArray)
      var imgName = imgArray[0];
      //image ext (second item in imgArray)
      var imgExt = imgArray[1];
      //image src path
      var srcPath = imgPath.split(imgFile , 1);
      // concatenate path and add "_hover" to image file name
      return srcPath + imgName+'_hover.'+ imgExt;
      };
   // get hover button array
   var hoveredButtons = new Array();
            
   $('.js_uniButton').mouseover (function() {
   $this = $(this);
      
      //get image path of this instance
      var imgPath = $this.children('img').attr('src');
      //cache img path url on initial mouseover
      if (typeof(hoveredButtons[ imgPath ]) == 'undefined') {
      hoveredButtons[ imgPath ] = getHoverPath( imgPath );
      //console.log('cache image path ' + imgPath + ' and hover path ' + hoveredButtons[ imgPath ]);
      }
      $this.children('img').attr('src' , hoveredButtons[ imgPath ]);
      
      //mouseout actions
      $this.mouseout(function() {
      //define this handler
         var $this = $(this), handler = arguments.callee;
         //unbind mouseout handler
         $this.unbind('mouseout', handler);
         // on mouseout, swap current image with original image path
         $this.children('img').attr('src' , imgPath);
      });
   });
   //Close On Doc Ready
})
</script>

$this = $(this);

$this =  $('.yourClass');