Javascript - How To Make Json Child Nodes (JSON Inside JSON)

I try to use the jquery + json to get all elements in form and build a JSON var to post in a ASP.NET MVC method.

[Code]....

It method get all fields in a form and build a JSON, but it dont put JSON inside JSON.

Example:

If i have the follow form:

<input name="person.name"><input name="person.age"><input name="person.address.street">

The serialized string build a JSON like this

{ "person.name": "??", "person.age": "??", "person.address.street": "??" }

I need a plugin or some function to generate like this:

{ "person": { "name" : "??", "age" : "??", "address":{ "street": "??" } } }