Thank you, Ivo and Benjamin, but still nothing.
Any of your approaches solved my problem.
Maybe my simple problem is not so simple:
I am not able to connect a jabber server by knowing: IP, PORT, USER, PASSWORD
I dont know its DOMAIN NAME, so i cannot build properly the JID.
How to connect to the IP and extract from the initial XMPP messages
the domain name to send my complete JID?