ubuntu-bug synaptic fails due to UnicodeDecodeError while reading dmesg

[Karl-Philipp Richter]

invoking `ubuntu-bug synaptic` causes

    $ ubuntu-bug synaptic
    ==== AUTHENTICATING FOR com.ubuntu.apport.root-info ===
    Authentication is required to collect system information for this problem report
    Authenticating as: richter,,, (richter)
    Password:
    ==== AUTHENTICATION COMPLETE ===
    ERROR: hook /usr/share/apport/package-hooks/source_synaptic.py crashed:
    Traceback (most recent call last):
      File "/usr/lib/python3/dist-packages/apport/report.py", line 197, in _run_hook
        symb['add_info'](report, ui)
    TypeError: add_info() takes 1 positional argument but 2 were given

    During handling of the above exception, another exception occurred:

    Traceback (most recent call last):
      File "/usr/lib/python3/dist-packages/apport/report.py", line 202, in _run_hook
        symb['add_info'](report)
      File "/usr/share/apport/package-hooks/source_synaptic.py", line 15, in add_info
        'CurrentDmesg.txt': 'dmesg | comm -13 --nocheck-order /var/log/dmesg -'})
      File "/usr/lib/python3/dist-packages/apport/hookutils.py", line 469, in attach_root_command_outputs
        buf = f.read().strip()
      File "/usr/lib/python3.4/codecs.py", line 313, in decode
        (result, consumed) = self._buffer_decode(data, self.errors, final)
    UnicodeDecodeError: 'utf-8' codec can't decode byte 0xe2 in position 2531522: invalid continuation byte

after I entered the sudo password at the prompt.

ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: apport 2.14.7-0ubuntu8
Uname: Linux 3.19.0-031900rc3-generic x86_64
ApportVersion: 2.14.7-0ubuntu8
Architecture: amd64
CurrentDesktop: Unity
Date: Fri Jan 9 20:11:56 2015
EcryptfsInUse: Yes
InstallationDate: Installed on 2015-01-03 (6 days ago)
InstallationMedia: Ubuntu 14.10 "Utopic Unicorn" - Release amd64 (20141022.1)
PackageArchitecture: all
SourcePackage: apport
SystemImageInfo:
 current build number: 0
 device name:
 channel: daily
 last update: Unknown
UpgradeStatus: No upgrade log present (probably fresh install)

[Marcus Tomlinson (marcustomlinson)]

This release of Ubuntu is no longer receiving maintenance updates. If this is still an issue on a maintained version of Ubuntu please let us know.

[Launchpad Janitor (janitor)]

[Expired for apport (Ubuntu) because there has been no activity for 60 days.]