Attempting to apply $conditions to the $hasMany['Event'] array only

gistfile1.php

<?php
  class Monitor extends AppModel {

    public $useTable = 'Monitors';

    public $hasMany = array(
  'Event' => array(
    'className' => 'Event',
    'foreignKey' => 'MonitorId'
  ),
  'Zone' => array(
    'className' => 'Zone',
    'foreignKey' => 'MonitorId'
  )
    );

  public function getEventsLastHour() {
    $conditions = array(
        'Events.StartTime > DATE_SUB(NOW(), INTERVAL 1 HOUR)'
    );
    return $this->find('all', compact('conditions'));
  }

  }
?>