function popup() {
  var i,p,v,obj,args=popup.arguments;
  
  arrPopups = getElementsByName_iefix('div','div_genres_categorias');
  for(i=0; i<arrPopups.length;i++){
    arrPopups[i].style.visibility = 'hidden';
  }

  for (i=0; i<(args.length-2); i+=3) 
  with (document) 
      if (getElementById && ((obj=getElementById(args[i]))!=null)) { 
        v=args[i+2];
        if (obj.style) { 
            obj=obj.style; 
              //oculto/muestro el combo de paginación para que no moleste
             if(document.getElementById('cmbRegPorPagina')!=null){
                document.getElementById('cmbRegPorPagina').style.display = (v=='mostrar')?'none':'';
             }
            v=(v=='mostrar')?'visible':(v=='ocultar')?'hidden':v; 
        }
        obj.visibility=v; 
      }
}
function getElementsByName_iefix(tag, name) {
     var elem = document.getElementsByTagName(tag);
     var arr = new Array();
     for(i = 0,iarr = 0; i < elem.length; i++) {
          att = elem[i].getAttribute("name");
          if(att == name) {
               arr[iarr] = elem[i];
               iarr++;
          }
     }
     return arr;
}