Jackson JSON not serializing Joda DateTime correctly

I have a Joda DateTime in an Order class:

public class Order {
    private DateTime creationTime;
    ...
}

I have initialized my mapper as follows:

mapper.configure(
        SerializationConfig.Feature.WRITE_DATES_AS_TIMESTAMPS, false);

When I serialize this class, I expect to see creationTime serialized in the ISO-8601 format as follows

{
  "creationTime" : "2011-01-01T09:00:00.000-04:00"
}

This is working perfectly fine in my unit test. However, in my web application, the exact same code is serializing all the DateTime fields:

{
  "creationTime" : {
    "year" : 2011,
    "dayOfMonth" : 17,
    "dayOfWeek" : 7,
    "era" : 1,
    "dayOfYear" : 107,
    "weekOfWeekyear" : 15,
    "weekyear" : 2011,
    "monthOfYe开发者_高级运维ar" : 4,
    "yearOfEra" : 2011,
    "yearOfCentury" : 11,
    "centuryOfEra" : 20,
    "millisOfSecond" : 590,
    "millisOfDay" : 40311590,
    "secondOfMinute" : 51,
    "secondOfDay" : 40311,
    "minuteOfHour" : 11,
    "minuteOfDay" : 671,
    "hourOfDay" : 11,
    "millis" : 1303053111590,
    "zone" : {
      "fixed" : false,
      "uncachedZone" : {
        "cachable" : true,
        "fixed" : false,
        "id" : "America/New_York"
      },
      "id" : "America/New_York"
    },
    "chronology" : {
      "zone" : {
        "fixed" : false,
        "uncachedZone" : {
          "cachable" : true,
          "fixed" : false,
          "id" : "America/New_York"
        },
        "id" : "America/New_York"
      }
    }
}

What am I missing? I am including jackson-core-asl-1.7.6.jar and jackson-mapper-asl-1.7.6.jar in my classpath in both cases.

In some online examples I saw an annotation on DateTime. I don't know if this is needed, but I tried it nevertheness. See below:

public class Order {
    @JsonSerialize(using=DateTimeSerializer.class)
    private DateTime creationTime;
    ...
}

This seems to make no difference.

Thanks.

P.S. Does anyone know if the Jackson mailing list is working? I posted this question on the user mailing list, but it doesn't show in the archives. The last post in the archives is dated 24 June 2010.

This seemed to do the trick for me: How to serialize Joda DateTime with Jackson JSON processer?

Basically, the idea was to create a class that extends org.codehaus.jackson.map.JsonSerializer with a overried serialize method:

public void serialize(DateTime value, JsonGenerator gen, SerializerProvider arg2) throws IOException, JsonProcessingException {
    gen.writeString(formatter.print(value));
}

Then just use that custom serializer in place of DateTimeSerializer.