Cannot hash datetime64 #188

In [59]: joblib.hashing.hash(numpy.zeros(dtype="<m8[s]", shape=(10,)))
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-59-8b9b8a0f034d> in <module>()
----> 1 joblib.hashing.hash(numpy.zeros(dtype="<m8[s]", shape=(10,)))

/export/data/home/gholl/venv/bleeding/lib/python3.4/site-packages/joblib/hashing.py in hash(obj, hash_name, coerce_mmap)
    199     else:
    200         hasher = Hasher(hash_name=hash_name)
--> 201     return hasher.hash(obj)

/export/data/home/gholl/venv/bleeding/lib/python3.4/site-packages/joblib/hashing.py in hash(self, obj, return_digest)
     51     def hash(self, obj, return_digest=True):
     52         try:
---> 53             self.dump(obj)
     54         except pickle.PicklingError as e:
     55             warnings.warn('PicklingError while hashing %r: %r' % (obj, e))

/usr/lib64/python3.4/pickle.py in dump(self, obj)
    408         if self.proto >= 4:
    409             self.framer.start_framing()
--> 410         self.save(obj)
    411         self.write(STOP)
    412         self.framer.end_framing()

/export/data/home/gholl/venv/bleeding/lib/python3.4/site-packages/joblib/hashing.py in save(self, obj)
    162                 # Python 3.2's memoryview raise a ValueError instead of a
    163                 # TypeError or a BufferError
--> 164                 self._hash.update(self._getbuffer(obj.flatten()))
    165 
    166             # We store the class, to be able to distinguish between

ValueError: cannot include dtype 'm' in a buffer