mojo-to-jenkins fails

I am trying to use mojo-to-jenkins and get the following failure:

$ python /usr/share/doc/mojo/contrib/jenkins/mojo-to-jenkins aaaa-bb-ccccc-ddddd lp:aaaa-bb-ccccc-ddddd
Traceback (most recent call last):
  File "/usr/share/doc/mojo/contrib/jenkins/mojo-to-jenkins", line 153, in <module>
    create_jobs(args)
  File "/usr/share/doc/mojo/contrib/jenkins/mojo-to-jenkins", line 85, in create_jobs
    manifest = get_manifest(tmpl_data['spec_repo'])
  File "/usr/share/doc/mojo/contrib/jenkins/mojo-to-jenkins", line 47, in get_manifest
    manifest = mojo.Spec(repo_dir).manifest
  File "/usr/lib/python2.7/dist-packages/mojo/__init__.py", line 82, in manifest
    stage=self.stage)
  File "/usr/lib/python2.7/dist-packages/mojo/__init__.py", line 211, in __init__
    self.config = spec.get_config(base=manifest_file, stage=stage)
  File "/usr/lib/python2.7/dist-packages/mojo/__init__.py", line 144, in get_config
    return os.path.join(self.local_dir, self.get_configs(base, stage)[-1])
  File "/usr/lib/python2.7/dist-packages/mojo/__init__.py", line 126, in get_configs
    if os.path.exists(os.path.join(self.local_dir, config))]
  File "/usr/lib/python2.7/posixpath.py", line 75, in join
    if b.startswith('/'):
AttributeError: 'NoneType' object has no attribute 'startswith'