var PNGBehavior = Class.create();
PNGBehavior.prototype = {
	initialize: function() {
		if (Browser.isIE && Browser.version >= 5.5 && Browser.version < 7) {
			
			$A(arguments).each( function(arg) {
				$$(arg).each( function(targ) {
					var bgstyle = targ.currentStyle.backgroundImage;
					var bgimg = bgstyle.substring(bgstyle.indexOf('"') + 1, bgstyle.lastIndexOf('"'));
					
					targ.style.filter = 'progid:DXImageTransform.Microsoft.AlphaImageLoader(src="' + bgimg + '", sizingMethod="scale")';
					targ.style.backgroundImage = 'none';
				});
			});
			
			for(var i=0; i<document.images.length; i++) {
				var img = document.images[i];
				var imgName = img.src.toUpperCase();
				if (imgName.substring(imgName.length-3, imgName.length) == 'PNG') {
					var imgID = (img.id) ? 'id="' + img.id + '" ' : '';
					var imgClass = (img.className) ? 'class="' + img.className + '" ' : '';
					var imgTitle = (img.title) ? 'title="' + img.title + '" ' : 'title="' + img.alt + '" ';
					var imgStyle = 'display:inline-block;' + img.style.cssText;
					if (img.parentElement.href) imgStyle = 'cursor:hand;' + imgStyle;
					var strNewHTML = '<span ' + imgID + imgClass + imgTitle
					+ ' style="' + 'width:' + img.offsetWidth + 'px; height:' + img.offsetHeight + 'px;' + imgStyle + ';'
					+ 'filter:progid:DXImageTransform.Microsoft.AlphaImageLoader'
					+ '(src=\'' + img.src + '\', sizingMethod=\'scale\');"></span>';
					img.outerHTML = strNewHTML;
					i--;
				}
			}
		}
  },
    
  replace: function() {
    if (Browser.isIE && Browser.version >= 5.5 && Browser.version < 7) {
      $A(arguments).each( function(arg) {
        $$(arg).each( function(targ) {
          var bgstyle = targ.currentStyle.backgroundImage;
          bgstyle = bgstyle.replace(/\.png/, '.gif');
          targ.style.backgroundImage = bgstyle;
        });
      });
    }
	}
};