Hello Tobias,XMPP is the ideal solution for your purpose IMHO. But i don't see where you need SOAP or RPC yet.
- You can use the XMPP core for contact list, presence etc... - JEP-0055 for the document search - JEP-0065 for transfering your documents
and i'm sure you will find some other useful Jeps too for your software. I am not a Java developer, so i can't comment the library stuff. Links: http://www.jabber.org/jeps/jep-0055.html http://www.jabber.org/jeps/jep-0065.html Alex
