var compareWin = null;

        function openCompare(){
                if ( ! compareWin || compareWin.closed) {
                        compareWin = window.open('/compare/', 'compare', 'toolbar=no,status=no,scrollbars=no,resizeble=no,menubar=no,width=500,height=327');
                }
                compareWin.focus();
                return true;
        }