new Ajax.Request(api_root + 'update_status',
  {
    method:'post',
    parameters: {username: 'john', password: 'mother', text='haaaaa'},
    onSuccess: function(transport) {
      var response = transport.responseText || "no response text";
      alert("congratulations you posted a dent");
    },
    onFailure: function(){ alert('na it\'s shit') }
  });