function blendImage(divid, aid, imageid, imagefile, millisec) {
	oA = document.getElementById(aid);
	if(!millisec){millisec=500;}
	var speed = Math.round(millisec / 100);
	var timer = 0;
	//set the current image as background
	document.getElementById(divid).style.backgroundImage = "url(" + document.getElementById(imageid).src + ")";
	//make image transparent
	changeOpac(0, imageid);
	//make new image
	document.getElementById(imageid).src = imagefile;
	//fade in image
	for(i = 0; i <= 100; i++) {
		setTimeout("changeOpac(" + i + ",'" + imageid + "')",(timer * speed));
		timer++;
		if(i==100&&oA){
			oA.href=document.getElementById(imageid).src.replace('type=prod','type=big_prod');
		}
	}
} 
//change the opacity for different browsers
function changeOpac(opacity, id) {
	var object = document.getElementById(id).style;
	object.opacity = (opacity / 100);
	object.MozOpacity = (opacity / 100);
	object.KhtmlOpacity = (opacity / 100);
	object.filter = "alpha(opacity=" + opacity + ")";
}