backup fails with error

Trying to do automatic backup.
It gives me this error:

Traceback (most recent call last):
  File "/usr/bin/duplicity", line 1403, in <module>
    with_tempdir(main)
  File "/usr/bin/duplicity", line 1396, in with_tempdir
    fn()
  File "/usr/bin/duplicity", line 1366, in main
    full_backup(col_stats)
  File "/usr/bin/duplicity", line 491, in full_backup
    bytes_written = dummy_backup(tarblock_iter)
  File "/usr/bin/duplicity", line 197, in dummy_backup
    while tarblock_iter.next():
  File "/usr/lib/python2.7/dist-packages/duplicity/diffdir.py", line 507, in next
    result = self.process(self.input_iter.next(), size)
  File "/usr/lib/python2.7/dist-packages/duplicity/diffdir.py", line 188, in get_delta_iter
    for new_path, sig_path in collated:
  File "/usr/lib/python2.7/dist-packages/duplicity/diffdir.py", line 281, in collate2iters
    for relem1 in riter1:
  File "/usr/lib/python2.7/dist-packages/duplicity/selection.py", line 187, in Iterate
    log.Debug(_("Selecting %s") % subpath.name)
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 29: ordinal not in range(128)

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: deja-dup 23.4-0ubuntu1
ProcVersionSignature: Ubuntu 3.5.0-8.8-generic 3.5.0
Uname: Linux 3.5.0-8-generic i686
ApportVersion: 2.4-0ubuntu6
Architecture: i386
Date: Tue Aug 7 12:10:58 2012
ExecutablePath: /usr/bin/deja-dup
InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Alpha i386 (20120730.1)
SourcePackage: deja-dup
UpgradeStatus: No upgrade log present (probably fresh install)