document.getElementsByClassName = function(cl) {
			var retnode = [];
			var myclass = new RegExp('\\b'+cl+'\\b');
			var elem = this.getElementsByTagName('*');
		
			for (var i = 0; i < elem.length; i++) {
				var classes = elem[i].className;
				if (myclass.test(classes)) retnode.push(elem[i]);
			}
		
			return retnode;
		};


		function setPolaroid(){
		 	var div_box_polaroid = new Array();
		 	div_box_polaroid = document.getElementsByClassName('extension');
	
	
		 	height_polaroid = null;
		 	for (y = 0; y < div_box_polaroid.length; y++) {
			 	//alert(div_box_polaroid[y].offsetHeight);
			 	if(height_polaroid < div_box_polaroid[y].offsetHeight){
						height_polaroid = 	div_box_polaroid[y].offsetHeight+ 1 + "px";
			 	}
			 	
			}
			//alert(height_polaroid);
			for (i = 0; i < div_box_polaroid.length; i++) {
		 			div_box_polaroid[i].style.height= height_polaroid;
			
			}
		}