improve connection to server that have an IPv6 but jabber server don't listen on that IP.

src/common/xmpp/client_nb.py

@@ -76,6 +76,9 @@ class NonBlockingClient:
         the client.
         """
         # to avoid recursive calls
+        if self.ip_addresses:
+            self._try_next_ip()
+            return
         if self.disconnecting: return
 
         log.info('Disconnecting NBClient: %s' % message)

src/common/xmpp/dispatcher_nb.py

@@ -154,6 +154,7 @@ class XMPPDispatcher(PlugIn):
         """
         Send an initial stream header
         """
+        self._owner.Connection.sendqueue = []
         self.Stream = simplexml.NodeBuilder()
         self.Stream.dispatch = self.dispatch
         self.Stream._dispatch_depth = 2