if (responder[callback] && typeof responder[callback] == 'function') { 
if (typeof responder[callback] == 'function') { 
  dispatch: function(callback, request, transport, json) {    this.each(function(responder) {      if (responder[callback] && typeof responder[callback] == 'function') {        try {          responder[callback].apply(responder, [request, transport, json]);        } catch (e) {}      }    });  }
6445	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/6445/81ea0800bc8ad92d491743716cd489cad7333723/prototype.js/buggy/vendor/rails/actionpack/lib/action_view/helpers/javascripts/prototype.js