[Ubuntu] /usr/bin/python does not match the python default version

$ sudo aptitude upgrade
The following packages will be upgraded: 
  python-aptdaemon python-aptdaemon-gtk  
The following partially installed packages will be configured:
  aptdaemon
2 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 0B/262kB of archives. After unpacking 4,096B will be used.
Do you want to continue? [Y/n/?] y
(Reading database ... 181739 files and directories currently installed.)
Preparing to replace python-aptdaemon-gtk 0.31+bzr506-0ubuntu4 (using .../python-aptdaemon-gtk_0.31+bzr506-0ubuntu5_all.deb) ...
Traceback (most recent call last):
  File "/usr/bin/pycentral", line 2304, in <module>
    main()
  File "/usr/bin/pycentral", line 2298, in main
    rv = action.run(global_options)
  File "/usr/bin/pycentral", line 1653, in run
    runtimes = get_installed_runtimes(with_unsupported=True)
  File "/usr/bin/pycentral", line 278, in get_installed_runtimes
    default_version = pyversions.default_version(version_only=True)
  File "/usr/share/pycentral-data/pyversions.py", line 172, in default_version
    raise ValueError, "/usr/bin/python does not match the python default version. It must be reset to point to %s" % debian_default
ValueError: /usr/bin/python does not match the python default version. It must be reset to point to python2.6
dpkg: warning: subprocess old pre-removal script returned error exit status 1

$ ls -l `which python`
lrwxrwxrwx 1 root root 24 2010-12-23 13:08 /usr/bin/python -> /etc/alternatives/python
$ update-alternatives --display python
python - auto mode
  link currently points to /usr/bin/python2.6
/usr/bin/python2.6 - priority 1
Current 'best' version is '/usr/bin/python2.6'.