Note that this does requite jQuery 1.5+.
$.ajaxSetup({ // Add a custom converter to convert ASP.NET JSON dates to JS Date object // That is convert { "\/Date(...)\/" } to { new Date(...) } converters: { "text json": function( textValue ) { return jQuery.parseJSON(textValue.replace(/"\\\/Date\((-?\d*)\)\\\/"/g, "new Date($1)")); } } });