mkdir over lftp triggers KeyError: 'permissions' in sftp server

[Michael Hudson-Doyle]

For example OOPS-1389SMPSSH1. The traceback is like this:

KeyError: 'permissions'

    Traceback (most recent call last):
  File "/srv/bazaar.launchpad.net/production/launchpad-rev-8526/lib/twisted/conch/ssh/session.py", line 105, in dataReceived
    self.client.transport.write(data)
  File "/srv/bazaar.launchpad.net/production/launchpad-rev-8526/lib/twisted/conch/ssh/session.py", line 156, in write
    self.proto.dataReceived(data)
  File "/srv/bazaar.launchpad.net/production/launchpad-rev-8526/lib/twisted/conch/ssh/filetransfer.py", line 53, in dataReceived
    f(data)
  File "/srv/bazaar.launchpad.net/production/launchpad-rev-8526/lib/twisted/conch/ssh/filetransfer.py", line 246, in packet_MKDIR
    d = defer.maybeDeferred(self.client.makeDirectory, path, attrs)
--- <exception caught here> ---
  File "/srv/bazaar.launchpad.net/production/launchpad-rev-8526/lib/twisted/internet/defer.py", line 106, in maybeDeferred
    result = f(*args, **kw)
  File "/srv/bazaar.launchpad.net/production/launchpad-rev-8526/lib/lp/codehosting/sftp.py", line 96, in decorator
    deferred = func(*args, **kwargs)
  File "/srv/bazaar.launchpad.net/production/launchpad-rev-8526/lib/lp/codehosting/sftp.py", line 403, in makeDirectory
    return self.transport.mkdir(
exceptions.KeyError: 'permissions'

I guess lftp behaves differently than sftp from openssh -- that works fine.