python celry + amazon EC2 failing because of the hash
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I'm trying to use Amazon EC2 in Python. When I'm trying to run the first sample from celery it works fine whe using RabbitMQ locally and whenever I'm relying on EC2, I'm receiving this message:
[2012-07-25 15:14:33,842: INFO/MainProcess] Got task from broker: celery_test.add[2eed1b15-fda7-4036-be92-a7fd921f0f5d]
[2012-07-25 15:14:33,881: WARNING/MainProcess] Task Handler ERROR: PicklingError("Can't pickle <type '_hashlib.hash'="">: attribute lookup _hashlib.HASH failed",)

I can't quite figure at which point/object it's failing to pickle.

The code is from their sample:

    @celery.task
    def add(x, y):
       return x + y

and I call it this way: add.delay(4, 4)

Any hints of what I'm doing wrong?

thanks!