socket error: <type 'exceptions.IOError'> - Too many read 0

[h2oz7v]

I am experiencing the following error when downloading a large mail
(it has two attachments totalling to 11MB). Mails in other maildir's
(on the same account) synch as normal.

offlineimap-git (v6.3.3-rc1)

 File "/usr/lib/python2.7/site-packages/offlineimap/folder/Base.py",
line 332, in copymessageto
    message = self.getmessage(uid)
  File "/usr/lib/python2.7/site-packages/offlineimap/folder/IMAP.py",
line 215, in getmessage
    initialresult = imapobj.uid('fetch', '%d' % uid, '(BODY.PEEK[])')
  File "/usr/lib/python2.7/site-packages/offlineimap/imaplib2.py",
line 1065, in uid
    return self._simple_command('UID', command, *args, **kw)
  File "/usr/lib/python2.7/site-packages/offlineimap/imaplib2.py",
line 1483, in _simple_command
    return self._command_complete(self._command(name, *args), kw)
  File "/usr/lib/python2.7/site-packages/offlineimap/imaplib2.py",
line 1259, in _command_complete
    typ, dat = rqb.get_response('command: %s => %%s' % rqb.name)
  File "/usr/lib/python2.7/site-packages/offlineimap/imaplib2.py",
line 161, in get_response
    raise typ(exc_fmt % str(val))
abort: command: UID => socket error: <type 'exceptions.IOError'> - Too
many read 0

Here is a (sanitised) debug log:

https://gist.github.com/68188f0c760eb298e493