What could be wrong with this way of loading from XML file?

Hello, I'm using the following code to load XML data from a file. The grid version I'm using is 1.0.1 (the latest one). The grid is displayed fine in MSIE but in Firefox I get this errors:

Element has no properties @ line 279 of gecko.js (it reads element.selectNodes = function (path) { ).
this._data.selectedNodes is not a function @ line 70 of table.js (it reads this._items = this._data ? this._data.selectNodes(this._itemPath) : null; )

<script language="Javascript" type="text/javascript">
<!--   
   var Grid_columns = ["Título", "Archivo", "Tamaño", "Tipo", "Fecha"];
  
   try {
      var Grid = new Active.Controls.Grid;
      var Grid_table = new Active.XML.Table;
      var Grid_column = new Active.Templates.Image;

      Grid_table.getImage = function(row, col) {
         return Grid.getDataProperty("text", row, 8);
      }

      function Grid_xmlGetData(url)
      {
         Grid_table.setProperty("URL", url);  
         Grid_table.request();
         Grid.setModel("data", Grid_table);
         Grid.refresh();
      };

      Grid_xmlGetData('/1.xml');
      Grid.setColumnText(function(i) { return Grid_columns[i] } );
      Grid.setProperty('column/count', 9);
      Grid.setColumnHeaderHeight("20px");
      Grid.setRowHeaderWidth("0px");      
      document.write(Grid);
}
catch (error) {
   document.write(error.description);
};
      
// -->
</script>

The XML file is

<?xml version="1.0" encoding="UTF-8"?>
<dir>
   <row>
      <title>xyz</title>
      <file>-</file>
      <size>-</size>
      <mime>directorio</mime>
      <date>28/06/2005 10:42:10</date>
      <recid>2</recid>
      <description>x</description>
      <type>directorio</type>
      <ext>dir</ext>
   </row>
</dir>

Any help is appreciated. Thanks.