Description of Problem:

The DataContractJsonSerializer is filling nullable value types with 0 instead of the true value even when a value is provided.  I would expect the nullable value type to default to null if not provided within the stream else be set to value provided by the stream.



Steps to reproduce the problem:
1. 


[DataContract]
public class c
{
    public c() { }

    [DataMember]
    public int? parm_id { get; set; }

    [DataMember]
    public decimal? val { get; set; }
}


2. 

string js = "{\"parm_id\":2}";
Use DataContractJsonSerializer to fill an instance with js.
        

Actual Results:

   parm_id contains 0.
   val contains 0

Expected Results:

   parm_id should contain 2.
   val should contain null.


How often does this happen? 

   Everytime.


Additional Information:

   Native windows returns expected results.