var blnDOMSUPPORT = (document.getElementById) ? true : false;
	function swapimage(imgtoswap){
	   if (blnDOMSUPPORT) {
	      var imgMain = document.getElementById('bigger_image');
	      var divParent;
	      var imgNew = document.createElement('img');
	      imgNew.src = eval(imgtoswap+".src");
	      imgNew.id = 'bigger_image';
	      divParent = imgMain.parentNode;
	      divParent.replaceChild(imgNew, imgMain);
	    }else{
		    document.images['bigger_image'].src = eval(imgtoswap+".src");}
	   }