session_start()

Hi, I was reading the manual of session_start() at http://www.php.net/manual/en/function.session-start.php But there's something strange to me. I find the following text in the first paragraph: session_start() creates a session (or resumes the current one based on the session id being passed via a GET variable or a cookie). It it really right that the session id can only be passed via GET parameters? What about to post the session id? Maybe there's a documentation problem. Greetings Oliver