Error when copying emails: wrong number of arguments passed in soledad adaptor

What I'm trying to do right now is copying emails from another account to an IMAP folder exposed by bitmask.

I'm not entirely sure if any get through, but I get a lot of the following in the log:

2017-04-21T00:06:03+0200 [leap.bitmask.mail.adaptors.soledad#error] Unable to format event {'log_namespace': 'leap.bitmask.mail.adaptors.soledad', 'log_level': <LogLevel=error>, 'log_logger': <Logger 'leap.bitmask.mail.adaptors.soledad'>, 'log_time': 1492725963.480269, 'log_source': None, 'log_format': <twisted.python.failure.Failure exceptions.TypeError: __init__() takes at most 2 arguments (3 given)>}: Log format must be unicode or bytes, not <twisted.python.failure.Failure exceptions.TypeError: __init__() takes at most 2 arguments (3 given)> 2017-04-21T00:06:03+0200 [leap.bitmask.mail.adaptors.soledad#error] Unable to format event {'log_namespace': 'leap.bitmask.mail.adaptors.soledad', 'log_level': <LogLevel=error>, 'log_logger': <Logger 'leap.bitmask.mail.adaptors.soledad'>, 'log_time': 1492725963.480827, 'log_source': None, 'log_format': <twisted.python.failure.Failure twisted.internet.defer.FirstError: FirstError[#3, [Failure instance: Traceback: <type 'exceptions.TypeError'>: __init__() takes at most 2 arguments (3 given) /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/base.py:1252:mainLoop /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/base.py:851:runUntilCurrent /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/defer.py:500:errback /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/defer.py:567:_startRunCallbacks --- <exception caught here> --- /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/defer.py:653:_runCallbacks /home/sune/src/pixelated/bitmask-dev/src/leap/bitmask/mail/adaptors/soledad.py:188:_catch_revision_conflict /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/failure.py:346:trap /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/defer.py:653:_runCallbacks /home/sune/src/pixelated/bitmask-dev/venv/src/leap.soledad.client/client/src/leap/soledad/client/adbapi.py:215:_errback /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/failure.py:346:trap /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/threadpool.py:250:inContext /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/threadpool.py:266:<lambda> /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/context.py:122:callWithContext /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/context.py:85:callWithContext /home/sune/src/pixelated/bitmask-dev/venv/src/leap.soledad.client/client/src/leap/soledad/client/adbapi.py:282:_runInteraction ]]>}: Log format must be unicode or bytes, not <twisted.python.failure.Failure twisted.internet.defer.FirstError: FirstError[#3, [Failure instance: Traceback: <type 'exceptions.TypeError'>: __init__() takes at most 2 arguments (3 given) /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/base.py:1252:mainLoop /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/base.py:851:runUntilCurrent /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/defer.py:500:errback /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/defer.py:567:_startRunCallbacks --- <exception caught here> --- /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/defer.py:653:_runCallbacks /home/sune/src/pixelated/bitmask-dev/src/leap/bitmask/mail/adaptors/soledad.py:188:_catch_revision_conflict /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/failure.py:346:trap /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/internet/defer.py:653:_runCallbacks /home/sune/src/pixelated/bitmask-dev/venv/src/leap.soledad.client/client/src/leap/soledad/client/adbapi.py:215:_errback /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/failure.py:346:trap /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/threadpool.py:250:inContext /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/threadpool.py:266:<lambda> /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/context.py:122:callWithContext /home/sune/src/pixelated/bitmask-dev/venv/local/lib/python2.7/site-packages/twisted/python/context.py:85:callWithContext /home/sune/src/pixelated/bitmask-dev/venv/src/leap.soledad.client/client/src/leap/soledad/client/adbapi.py:282:_runInteraction ]]>