Bug#495011: WAR for this bug

[Justy Burdick]

Apparently, this error can be avoided by installing the previous version of
Rabbyt

You can try installing an older version:
http://pypi.python.org/pypi/Rabbyt/0.7

thread here:

http://groups.google.com/group/snowballz-fans/t/d3dcb78e479df639