Exceptions when marking a bunch of channels as favorites

[whirm]

This one appears repeatedly:

Unhandled Error
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/twisted/internet/base.py", line 1192, in run
    self.mainLoop()
  File "/usr/lib/python2.7/dist-packages/twisted/internet/base.py", line 1201, in mainLoop
    self.runUntilCurrent()
  File "/usr/lib/python2.7/dist-packages/twisted/internet/base.py", line 824, in runUntilCurrent
    call.func(*call.args, **call.kw)
  File "/usr/lib/python2.7/dist-packages/twisted/internet/task.py", line 218, in __call__
    d = defer.maybeDeferred(self.f, *self.a, **self.kw)
--- <exception caught here> ---
  File "/usr/lib/python2.7/dist-packages/twisted/internet/defer.py", line 139, in maybeDeferred
    result = f(*args, **kw)
  File "/var/data/feina/code/delft/tribler/Tribler/dispersy/community.py", line 1192, in take_step
    self.create_introduction_request(candidate, self.dispersy_enable_bloom_filter_sync)
  File "/var/data/feina/code/delft/tribler/Tribler/dispersy/community.py", line 2657, in create_introduction_request
    assert list(bloom_filter.not_filter((packet,) for packet in packets)) == [], "does not have all correct bits set before transmission"
exceptions.AssertionError: does not have all correct bits set before transmission