Thanks ceene for new version. I've registered / validated my number without problems. I have the same disconnected problems as sicelo:

INCOMING:
<iq>
from=g.us
id=get_groups_3
type=error
<error>
code=501
text=feature-not-implemented

INCOMING:
<stream:error>
<ack>

There was an IO error: Connection closed by server.
Connection closed.
Stopping timers.
Freeing up the connection.
Freeing up the socket.
Yappari will retry the connection in 10 seconds.
Invalid length 0x3