posTop=0;

 

function newWindow(scroll, w, h, location, name) {

    if (screen) {

        posLeft=((screen.width-w)/2);

        posTop=((screen.height-h)/2);

    }

    window.open(location, name, "scrollbars="+scroll+",width="+w+",height="+h+",left="+posLeft+",top="+posTop+"");

}