$date and ISODate again and again

I've a REST application with a 2.6.5 mongodb persistence.

My DAO use mongojack/JacksonDBCollection (ie JacksonDBCollection.insert, JacksonDBCollection.update)

When i insert/update a document containing a date I have the following (mongodb log) :

update: { _id: ObjectId('5494665384ae2a79c5817dcd'), title: "THE TITLE",.... , date: new Date(1419012062698),... }


The field date, when querying with mongo shell is ISODate("2014-12-19T18:01:02.698Z").
Well. Now when I querying with application, I build the query with the mongo-driver QueryBuilder.
The resulting query is the following (mongodb log) :

{ $or: [ { title: "THE TITLE", date: { $gte: { $date: "2014-11-18T23:00:00.000Z" }, $lte: { $date: "2014-12-20T22:59:59.000Z" } } } ] }


which returns no results.
I think that the date format is not correct (following the forum discussions on the subject) so I should use ISODate as query :

{ $or: [ { title: "THE TITLE", date: { $gte: ISODate("2014-11-18T23:00:00.000Z"), $lte: ISODate("2014-12-20T22:59:59.000Z") } } ] } 

which works.
So, my question is : what is the origin of problem ? The use of mongojack or the use of QueryBuilder ?
What is opinion?