def __init__(self, client):
gobject.GObject.__init__(self)
self._client = client
self._core = SIPCore(self._client)
self._core.connect("invite-received", self._on_invite_received)
self._core.connect("invite-answered", self._on_invite_answered)
self._core.connect("cancel-received", self._on_cancel_received)
self._calls = {} # Call-ID => call, handle_id
