'Fail all pending TCP DNS queries if the TCP connection attempt
fails.
@see: L{twisted.internet.protocol.ClientFactory}
@param connector: Not used.
@type connector: L{twisted.internet.interfaces.IConnector}
@param reason: A C{Failure} containing information about the
cause of the connection failure. This will be passed as the
argument to C{errback} on every pending TCP query
C{deferred}.
@type reason: L{twisted.python.failure.Failure}'

def clientConnectionFailed(self, connector, reason):

    pending = self.controller.pending[:]
    del self.controller.pending[:]
    for pendingState in pending:
        d = pendingState[0]
        d.errback(reason)
