// XMLSerializer is implemented by Gecko, Webkit and Opera. 
if (!window.XMLSerializer) {
    
    window.XMLSerializer = function ()
    {
    
    }
    
    window.XMLSerializer.prototype.serializeToString = function (doc)
    {
        try {
            return doc.xml;
        } catch (e) {
            alert ('XMLSerializer.serializeToString not supported');
        }
    } 
}