AttributeError: 'module' object has no attribute 'gpg_options'

I am using the latest version of duplicity (0.6.08), and I am getting the following error:

Traceback (most recent call last):
  File "/usr/bin/duplicity", line 1239, in ?
    with_tempdir(main)
  File "/usr/bin/duplicity", line 1232, in with_tempdir
    fn()
  File "/usr/bin/duplicity", line 1205, in main
    full_backup(col_stats)
  File "/usr/bin/duplicity", line 416, in full_backup
    globals.backend)
  File "/usr/bin/duplicity", line 294, in write_multivol
    globals.gpg_profile, globals.volsize)
  File "/usr/lib/python2.4/site-packages/duplicity/gpg.py", line 272, in GPGWriteFile
    file = GPGFile(True, path.Path(filename), profile)
  File "/usr/lib/python2.4/site-packages/duplicity/gpg.py", line 105, in __init__
    if globals.gpg_options:
AttributeError: 'module' object has no attribute 'gpg_options'

This occurs when I execute the following command:

/usr/bin/duplicity -v3 --full-if-older-than 14D --encrypt-key=B8C500C9 --sign-key=B8C500C9 --exclude /share/osowski --exclude /share/michalson --include=/share/kaeding --include=/home/jkaeding --include=/home/malvarado --exclude=** / s3+http://mybucket/marshall

I am not sure if I am missing some python module relating to GPG? I have python-gnupginterface installed (using the Ubuntu package).

Does this look familiar to anyone? Thanks!