function disabled_cat(count_cats) {

     if(document.add_link.cago_1[0].selected == true) {

      document.add_link.cago_2.disabled = true;
      document.add_link.cago_3.disabled = true;
      document.add_link.cago_2[0].selected = true;
      document.add_link.cago_3[0].selected = true;

     }
     else {

      document.add_link.cago_2.disabled = false;
      document.add_link.cago_3.disabled = false;

     }

     if(document.add_link.cago_2[0].selected == true) {

      document.add_link.cago_3.disabled = true;
      document.add_link.cago_3[0].selected = true;

     }
     else {

      document.add_link.cago_3.disabled = false;

     }

     for(i=1 ; i < count_cats ; i++) {

      document.add_link.cago_1[i].disabled = false;
      document.add_link.cago_2[i].disabled = false;
      document.add_link.cago_3[i].disabled = false;

     }

     for(i=1 ; i < count_cats ; i++) {

      if(document.add_link.cago_1[i].selected == true) {

       document.add_link.cago_2[i].disabled = true;
       document.add_link.cago_3[i].disabled = true;

      }

      if(document.add_link.cago_2[i].selected == true) {

       document.add_link.cago_1[i].disabled = true;
       document.add_link.cago_3[i].disabled = true;

      }

      if(document.add_link.cago_3[i].selected == true) {

       document.add_link.cago_1[i].disabled = true;
       document.add_link.cago_2[i].disabled = true;

      }

     }

    }

    function Contar(entrada,salida,texto,caracteres) {
     var entradaObj=getObject(entrada);
     var salidaObj=getObject(salida);
     var longitud=caracteres - entradaObj.value.length;
     if(longitud <= 0) {
      longitud=0;
      texto='<span class="disable">'+texto+'</span>';
      entradaObj.value=entradaObj.value.substr(0,caracteres);
     }
     salidaObj.innerHTML = texto.replace("{CHAR}","noch "+longitud+" von ");
    }

    function getObject(obj) {
     var theObj;
     if(document.all) {
      if(typeof obj=="string") {
       return document.all(obj);
      }
      else {
       return obj.style;
      }
     }
     if(document.getElementById) {
      if(typeof obj=="string") {
       return document.getElementById(obj);
      }
      else {
       return obj.style;
      }
     }
     return null;
    }

    function validate(obj,modo,porDefecto, min) {
     var texto = obj.value;
     for(i=0 ; i < 100 ; i++) {
      texto = texto.replace(" ","");
     }
     do {
      texto = texto.replace(/\|\|/,"|");
     } while(/\|\|/.test(texto));
     if(modo=="url") {
      if(texto.substr(0,7)!="http://" && texto.substr(0,8)!="https://")
       if(texto!='') {
        texto = "http://" + texto;
       }
     }
     obj.value = texto;
    }