var wImg=null;
function queryWin(w){return !(w==null||w.closed||typeof w=="undefined")}
function focusWin(w){if(w.blur)w.focus()}
function show(url,width,height){
	width = (!width)? 500: width;
	height = (!height)? 500: height;
	var ff='width=' + width + ',height=' + height + ',resizable,scrollbars=no';
	if(queryWin(wImg)){wImg.location.href=url; focusWin(wImg)}
	else{wImg=window.open(url,"wImg",ff); focusWin(wImg)}
	return false;
}