Steve Snyder:
obfs3 won't build/run on RHEL6/CentOS6 due to the Python 2.7.x (plus many, many subpackages) requirement.
That's a pity: obfsproxy can actually run with Python 2.6 as I've happily discovered when doing packages for Debian Squeeze.
I hope George will be able to lower the requierements in the next release.