I have a javascript function that calls an MVC controller with JSON data:
var specsAsJson = JSON.stringify(specs);
$.post(\'/Home/Save\', { jsonData: specsAs
JavaScript (well, EcmaScript) defines its DateTime string interchange format based on a simplification of the ISO-8601 standard.
XML Schema defines its DateTime string interchange format based on ISO-8601 also.
I have found it handy to use the .NET class System.Runtime.Remoting.Metadata.W3cXsd2001.SoapDateTime to handle conversion from .NET DateTime values to XML formats and back.
Since JavaScript is based on the same ISO-8601 standard, perhaps it will work for your JSON case as well.