Is it possible to use nullable parameters ?

I have

      [DirectMethod]
	public void Test(int? testParameter)
	{
	}
called as
Ext.net.DirectMethods.Test(null, {
				commplete: Ext.emptyFn
				
			});
And I got the


Newtonsoft.Json.JsonReaderException: Unexpected end when reading integer. Line 0, position 0. at Newtonsoft.Json.JsonTextReader.ReadAsInt32() at Newtonsoft.Json.Serialization.JsonSerializerIntern alReader.ReadForType(JsonReader reader, JsonContract contract, Boolean hasConverter, Boolean inArray) at Newtonsoft.Json.Serialization.JsonSerializerIntern alReader.Deserialize(JsonReader reader, Type objectType) at Newtonsoft.Json.JsonConvert.DeserializeObject(Stri ng value, Type type, JsonSerializerSettings settings) at Ext.Net.JSON.Deserialize(String value, Type type, List`1 converters, IContractResolver resolver) at Ext.Net.DirectMethod.Invoke(Object target, HttpContext context, ParameterCollection args) at Ext.Net.ResourceManager.RaisePostBackEvent(String eventArgument)