GWT (Client) = How to convert Object to JSON and send to Server?

I know that GWT has a good RPC support. But for various purposes I need to build this on my own:

1.) How can I convert a Bean Object (on the Client Side) like;

class MyPerson {

String name;
String getName();
void setName(String name);
//..    
}

with GWT into a JSON String? (Ideally only using libraries that come officially from GWT/Google).

2.) Secondly, how can I send this generated JSON String from the Client side to any Server also using any GWT Client Logik. (Ideally only using libraries that come officially from GWT/Google).

I have searched a lot, but the examples never show how to send data but only to receive JSON data.

Thank you very much!!! Jens