Without this flag it is necessary to wait for e.g. 120s after closing
down a 'BaseManager' server before restarting, due to the socket being
in the TIME_WAIT state. 

Example error, which occurs if a server is started, data transmitted
down the socket, the server shut down, then restarted:

     File "/usr/local/lib/python2.6/multiprocessing/connection.py", line
220, in __init__
        self._socket.bind(address)
     File "<string>", line 1, in bind
        error: [Errno 48] Address already in use


I added (locally):
     self._socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

to SocketListener.__init__, and it resolves the issue.