mx:HTTPService questions

[nrmncook]

Hello, I need some help with the mx:HTTPService component. I have a Java servlet that takes an XML document as the body of a POST request and gives another XML document as a response. After that, every interaction with my Flex application implies another similar action: POST request with text/xml contentType -> XML response. How do I specify the body of my POST request? Another thing I fail to grasp from the documentation is how do I manage cookies via HTTPService. If the server gives me a cookie (via SetCookie: foo=foo) how do I put it in my subsequent requests (via Cookie: foo=foo)? Thanks in advance and sorry for my poor english.

Samuele