Android version fails to deserialize nullable enum

[tho-sch]

I am using version 2.0.0.6 (latest on NuGet) in a Xamarin.Android project targeting API Level 15. The following Json string fails to deserialize:
{"NewDataAvailable":false,"ServiceAction":null}

This is the corresponding class:

[DataContract]
public class DeviceNotification
{
    [DataMember]
    public bool NewDataAvailable { get; set; }

    [DataMember]
    public DeviceServiceAction? ServiceAction { get; set; }
}

DeviceServiceAction is an enum.

When trying to deserialize, I receive the following error:
System.Exception: Bad number (int) at 42 (found: '\110')

The problem only occurs when ServiceAction is null.