Event.addBehavior({  
  'textarea.fckeditor': function(){
    var oFCKeditor = new FCKeditor( this.id, '100%', '300', 'Basic' ) ;
    oFCKeditor.Config["CustomConfigurationsPath"] = "/javascripts/new/fckconfig.js";
    oFCKeditor.ReplaceTextarea(); 
  }
});