var http_request = false;
var winname;
var winnr;

function mouseY(evt) {
  if (evt.pageY) return evt.pageY;
  else if (evt.clientY)
    return evt.clientY + (document.documentElement.scrollTop ?
     document.documentElement.scrollTop :
     document.body.scrollTop);
  else return null;
}

function getContent(url, layer_id) {

  winname = layer_id;
  //resize_div();
  document.getElementById("ajax_container").style.display = "block";
  document.getElementById(layer_id).style.display = "block";
  document.getElementById(layer_id).style.cursor = "wait";
  http_request = false;

  if (window.XMLHttpRequest) { // Mozilla, Safari,... 
    http_request = new XMLHttpRequest();
    if (http_request.overrideMimeType) {
      http_request.overrideMimeType('text/xml');
      // zu dieser Zeile siehe weiter unten 
    }
  } else if (window.ActiveXObject) { // IE 
    try {
      http_request = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e) {
      try {
        http_request = new ActiveXObject("Microsoft.XMLHTTP60");

      } catch (e) { }
    }
  }

  if (!http_request) {
    return false;
  }
  http_request.onreadystatechange = showContent;
  http_request.open('GET', url, true);
  http_request.send(null);

}

function showContent() {
  if (http_request.readyState == 4) {
    var answer = http_request.responseText;
    document.getElementById(winname).innerHTML = answer;
    document.getElementById(winname).style.cursor = "default";
  }

}

function close_div(layer_id) {
  document.getElementById(layer_id).style.display = "none";
  document.getElementById(layer_id).style.height = "1px";
}