Cannot store custom objects via HotRod and read via REST

public void testCustomObjectHotRodPutEmbeddedRestGet() throws Exception{
      final String key = "4";
      Person p = new Person("Martin");
      // 1. Put with Hot Rod
      RemoteCache<String, Object> remote = cacheFactory.getHotRodCache();
      assertEquals(null, remote.withFlags(Flag.FORCE_RETURN_VALUE).put(key, p));

      // 2. Get with Embedded
      assertTrue(cacheFactory.getEmbeddedCache().get(key) instanceof Person);
      assertEquals(p.getName(), ((Person) cacheFactory.getEmbeddedCache().get(key)).getName());

      // 3. Get with REST
      HttpMethod get = new GetMethod(cacheFactory.getRestUrl() + "/" + key);
      cacheFactory.getRestClient().executeMethod(get);

      assertEquals(HttpServletResponse.SC_OK, get.getStatusCode());  
//^^^ fails here - status code 500, status text: NullPointerException

      Object returnedPerson = remote.getRemoteCacheManager().getMarshaller().objectFromByteBuffer(get.getResponseBodyAsString().getBytes());
      assertTrue(returnedPerson instanceof Person);
      assertEquals(p.getName(), ((Person) returnedPerson).getName());
   }

   public static class Person implements Serializable {

      private String name;

      public Person(String name) {
         this.name = name;
      }

      public String getName() {
         return name;
      }
   }