Internal error on push

I used 'bzr push' to a saved ssh location and got the following error:

Traceback (most recent call last):
  File "/usr/bin/bzr", line 147, in <module>
    sys.stdout.flush()
ValueError: I/O operation on closed file
Segmentation fault
bzr: ERROR: bzrlib.errors.TooManyConcurrentRequests: The medium '<bzrlib.smart.medium.SmartSSHClientMedium object at 0xa4931ac>' has reached its concurrent request limit. Be sure to finish_writing and finish_reading on the currently open request.

Traceback (most recent call last):
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 857, in run_bzr_catch_errors
    return run_bzr(argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 797, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 499, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.5/site-packages/bzrlib/builtins.py", line 802, in run
    use_existing_dir=use_existing_dir)
  File "/usr/lib/python2.5/site-packages/bzrlib/push.py", line 169, in _show_push_branch
    stop_revision=revision_id)
  File "/usr/lib/python2.5/site-packages/bzrlib/decorators.py", line 138, in read_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/python2.5/site-packages/bzrlib/branch.py", line 1782, in push
    target.unlock()
  File "/usr/lib/python2.5/site-packages/bzrlib/remote.py", line 1471, in unlock
    self._unlock(branch_token, repo_token)
  File "/usr/lib/python2.5/site-packages/bzrlib/remote.py", line 1438, in _unlock
    repo_token or '')
  File "/usr/lib/python2.5/site-packages/bzrlib/smart/client.py", line 111, in call
    result, protocol = self.call_expecting_body(method, *args)
  File "/usr/lib/python2.5/site-packages/bzrlib/smart/client.py", line 124, in call_expecting_body
    method, args, expect_response_body=True)
  File "/usr/lib/python2.5/site-packages/bzrlib/smart/client.py", line 58, in _call_and_read_response
    readv_body=readv_body)
  File "/usr/lib/python2.5/site-packages/bzrlib/smart/client.py", line 39, in _send_request
    protocol_version)
  File "/usr/lib/python2.5/site-packages/bzrlib/smart/client.py", line 94, in _construct_protocol
    request = self._medium.get_request()
  File "/usr/lib/python2.5/site-packages/bzrlib/smart/medium.py", line 610, in get_request
    return SmartClientStreamMediumRequest(self)
  File "/usr/lib/python2.5/site-packages/bzrlib/smart/medium.py", line 785, in __init__
    raise errors.TooManyConcurrentRequests(self._medium)
TooManyConcurrentRequests: The medium '<bzrlib.smart.medium.SmartSSHClientMedium object at 0xa4931ac>' has reached its concurrent request limit. Be sure to finish_writing and finish_reading on the currently open request.

bzr 1.6.1 on python 2.5.2 (linux2)
arguments: ['/usr/bin/bzr', 'push']
encoding: 'UTF-8', fsenc: 'UTF-8', lang: 'en_GB.UTF-8'
plugins:
  bzrtools /usr/lib/python2.5/site-packages/bzrlib/plugins/bzrtools [1.6.0]
  launchpad /usr/lib/python2.5/site-packages/bzrlib/plugins/launchpad [unknown]
*** Bazaar has encountered an internal error.
    Please report a bug at https://bugs.launchpad.net/bzr/+filebug
    including this traceback, and a description of what you
    were doing when the error occurred.