/**
  * Retreive Proxy
  *
  * Retrieve a previously registered <b>IProxy</b> from the <b>Model</b> by name.
  *
  * @param string $proxyName Name of the <b>IProxy</b> instance to be retrieved.
  * @return IProxy The <b>IProxy</b> previously regisetered by <var>proxyName</var> with the <b>Model</b>.
  */
 public function retrieveProxy($proxyName)
 {
     return isset($this->model) ? $this->model->retrieveProxy($proxyName) : null;
 }