FileExists error when preparing to download file

[James Westby]

[2012-02-25 12:34:57,652: ERROR/MainProcess] Task djpkgme.tasks.BuildPackageTask[eb6e519d-585c-483b-a6f1-c4ed89992b75] raised exception: OSError(17, 'File exists')
Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.6/celery/execute/trace.py", line 47, in trace
    return cls(states.SUCCESS, retval=fun(*args, **kwargs))
  File "/usr/lib/pymodules/python2.6/celery/app/task/__init__.py", line 247, in __call__
    return self.run(*args, **kwargs)
  File "/srv/pkgme-service.canonical.com/production/pkgme-service/sourcecode/../src/djpkgme/tasks.py", line 246, in run
    packaged_app_path = self.build_package(metadata, overrides)
  File "/srv/pkgme-service.canonical.com/production/pkgme-service/sourcecode/../src/djpkgme/tasks.py", line 223, in build_package
    download_path, output_dir, metadata['package_name'])
  File "/srv/pkgme-service.canonical.com/production/pkgme-service/sourcecode/../src/djpkgme/tasks.py", line 156, in prepare_file
    os.makedirs(extraction_path)
  File "/usr/lib/python2.6/os.py", line 157, in makedirs
    mkdir(name, mode)
OSError: [Errno 17] File exists

Found when looking in the logs, I don't have much more data than that.