I know microsoft did all it could to prevent XMPP support in N9, but community is strong:
mc-tool add gabble/jabber [account] string:account=[user_id] string:password=[passwd] string:server=[server] bool:require-encryption=1 bool:ignore-ssl-errors=1
and
mc-tool enable [output_of_previous]
Now I can enjoy our corporate high security and standard compliant instant messaging over XMPP.