telepathy-butterfly crashed with TypeError: _on_session_completed() takes exactly 3 arguments (2 given)

[fabio]

Binary package hint: telepathy-butterfly

telepathy crash suddenly after system startup
telepathy 0.5.15-1

ProblemType: Crash
DistroRelease: Ubuntu 11.04
Package: telepathy-butterfly 0.5.15-1
ProcVersionSignature: Ubuntu 2.6.38-8.40-generic 2.6.38.2
Uname: Linux 2.6.38-8-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
CheckboxSubmission: 4766a9f80d6f6dddc6cba0fdd3200780
CheckboxSystem: b633b4f40868d491c2ae5b50030ce6f3
Date: Wed Apr 6 09:09:35 2011
EcryptfsInUse: Yes
ExecutablePath: /usr/lib/telepathy/telepathy-butterfly
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Beta amd64 (20110330)
InterpreterPath: /usr/bin/python2.7
PackageArchitecture: all
ProcCmdline: /usr/bin/python /usr/lib/telepathy/telepathy-butterfly
ProcEnviron:
 SHELL=/bin/bash
 LANGUAGE=en_US:en
 LANG=en_US.UTF-8
PythonArgs: ['/usr/lib/telepathy/telepathy-butterfly']
SourcePackage: telepathy-butterfly
Title: telepathy-butterfly crashed with TypeError: _on_session_completed() takes exactly 3 arguments (2 given)
Traceback: TypeError: _on_session_completed() takes exactly 3 arguments (2 given)
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm admin audio cdrom dialout dip fax floppy fuse lpadmin netdev plugdev sambashare tape vboxusers video

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make Ubuntu better. This particular crash has already been reported and is a duplicate of bug #735815, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.