getParams: function(node){
        var buf = [], bp = this.baseParams;
        for(var key in bp){
            if(typeof bp[key] != "function"){
                buf.push(encodeURIComponent(key), "=", encodeURIComponent(bp[key]), "&");
            }
        }
        buf.push("node=", encodeURIComponent(node.id));
        return buf.join("");
    },



    params = Hash.toQueryString(params);




    var Hash = function(obj) {
  Object.extend(this, obj || {});
};

Object.extend(Hash, {
  toQueryString: function(obj) {
    var parts = [];

	  this.prototype._each.call(obj, function(pair) {
      if (!pair.key) return;

      if (pair.value && pair.value.constructor == Array) {
        var values = pair.value.compact();
        if (values.length < 2) pair.value = values.reduce();
        else {
        	key = encodeURIComponent(pair.key);
          values.each(function(value) {
            value = value != undefined ? encodeURIComponent(value) : '';
            parts.push(key + '=' + encodeURIComponent(value));
          });
          return;
        }
      }
      if (pair.value == undefined) pair[1] = '';
      parts.push(pair.map(encodeURIComponent).join('='));
	  });

    return parts.join('&');
  }
});






// Serialize an array of form elements or a set of
	// key/values into a query string
	param: function( a ) {
		var s = [];

		// If an array was passed in, assume that it is an array
		// of form elements
		if ( a.constructor == Array || a.jquery )
			// Serialize the form elements
			jQuery.each( a, function(){
				s.push( encodeURIComponent(this.name) + "=" + encodeURIComponent( this.value ) );
			});

		// Otherwise, assume that it's an object of key/value pairs
		else
			// Serialize the key/values
			for ( var j in a )
				// If the value is an array then the key names need to be repeated
				if ( a[j] && a[j].constructor == Array )
					jQuery.each( a[j], function(){
						s.push( encodeURIComponent(j) + "=" + encodeURIComponent( this ) );
					});
				else
					s.push( encodeURIComponent(j) + "=" + encodeURIComponent( a[j] ) );

		// Return the resulting serialization
		return s.join("&");
	},