MM3: Expected unicode, found <type 'datetime.datetime'>:

[Bernhard Schmidt]

Mailman 3.0.0b1+ (hg checkout of two days ago) throws the following error in the log

Apr 18 12:53:57 2012 (23857) Uncaught runner exception: Expected unicode, found <type 'datetime.datetime'>: datetime.datetime(2012, 4, 18, 10, 53, 56, 403336)
Apr 18 12:53:58 2012 (23857) Traceback (most recent call last):
  File "/usr/local/mailman/src/mailman/core/runner.py", line 138, in _one_iteration
    self._process_one_file(msg, msgdata)
  File "/usr/local/mailman/src/mailman/core/runner.py", line 220, in _process_one_file
    keepqueued = self._dispose(mlist, msg, msgdata)
  File "/usr/local/mailman/src/mailman/runners/incoming.py", line 67, in _dispose
    process(mlist, msg, msgdata, start_chain)
  File "/usr/local/mailman/src/mailman/core/chains.py", line 90, in process
    link.function(mlist, msg, msgdata)
  File "/usr/local/mailman/src/mailman/chains/hold.py", line 146, in _process
    request_id = hold_message(mlist, msg, msgdata, None)
  File "/usr/local/mailman/src/mailman/app/moderator.py", line 105, in hold_message
    RequestType.held_message, message_id, msgdata)
  File "/usr/local/mailman/src/mailman/model/requests.py", line 87, in hold_request
    token = getUtility(IPendings).add(pendable, timedelta(days=5000))
  File "/usr/local/mailman/src/mailman/model/pending.py", line 130, in add
    keyval = PendedKeyValue(key=key, value=value)
  File "/usr/local/mailman/src/mailman/model/pending.py", line 54, in __init__
    self.value = value
  File "/usr/lib/python2.7/dist-packages/storm/properties.py", line 67, in __set__
    obj_info.variables[column].set(value)
  File "/usr/lib/python2.7/dist-packages/storm/variables.py", line 396, in parse_set
    % (type(value), value))
TypeError: Expected unicode, found <type 'datetime.datetime'>: datetime.datetime(2012, 4, 18, 10, 53, 56, 403336)
Apr 18 12:53:58 2012 (23857) SHUNTING: 1334746438.043432+d81b75cc8924fd572477ebc0358bde18bf755fd9