function insert_bbcode(aTag, eTag, editform, editelement) {
  var input = document.forms[editform].elements[editelement];
  input.focus();
  if(aTag == '[url=]' || aTag == '[url]') {
    var url = prompt("Bitte URL eingeben:", "http://");
    if(url == null) return;
    aTag = '[url=' + url + ']';
  }
  else if(aTag == '[img]') {
    var url = prompt("Bitte URL zum Bild eingeben:", "http://");
    if(url == null) return;
    aTag = '[img]' + url;
  }

  if(typeof document.selection != 'undefined') {
    var range = document.selection.createRange();
    var insText = range.text;
    range.text = aTag + insText + eTag;
    range = document.selection.createRange();
    if (insText.length == 0) {
      range.move('character', aTag.length + insText.length + eTag.length);
    } else {
      range.moveStart('character', aTag.length + insText.length + eTag.length);      
    }
    range.select();
  }
  else if(typeof input.selectionStart != 'undefined')
  {
    var start = input.selectionStart;
    var end = input.selectionEnd;
    var insText = input.value.substring(start, end);
    input.value = input.value.substr(0, start) + aTag + insText + eTag + input.value.substr(end);
    var pos;
    if (insText.length == 0) {
      pos = start + aTag.length + insText.length + eTag.length;
    } else {
      pos = start + aTag.length + insText.length + eTag.length;
    }
    input.selectionStart = pos;
    input.selectionEnd = pos;
  }
  else
  {
    var pos;
    var re = new RegExp('^[0-9]{0,3}$');
    while(!re.test(pos)) {
      pos = prompt("Einfügen an Position (0.." + input.value.length + "):", "0");
    }
    if(pos > input.value.length) {
      pos = input.value.length;
    }
    var insText = prompt("Bitte geben Sie den zu formatierenden Text ein:");
    input.value = input.value.substr(0, pos) + aTag + insText + eTag + input.value.substr(pos);
  }
}