function displayWindow(theURL,winName,width,height,features) 
{
    var window_width = width;
    var window_height = height;
    var newfeatures= features;
    var window_top = (screen.height-window_height)/2;
    var window_left = (screen.width-window_width)/2;
 newWindow=window.open(''+ theURL + '',''+ winName + '','width=' + window_width + ',height=' + window_height + ',top=' + window_top + ',resizable=yes, left=' + window_left + ',features=' + newfeatures + '');
     newWindow.focus();
} 

function displayWindow2(url, jmeno, w, h) { 
  if (document.all) {
    w = w + 20;
    h = h + 10;
  }
  popupWin = window.open(url, jmeno, 'resizable=1,top=20,left=20,menubar=0,scrollbars=yes,width='+ w +',height='+ h);
}

function popup(href) {
window.open(href);
}