Bug#645963: gnome-tweak-tool no start

[miguel]

Package: gnome-tweak-tool
Version: 3.0.4-2
Severity: important

Dear Maintainer,
*** Please consider answering these questions, where appropriate ***

   * What led up to the situation?
        I am trying to open the program gnome-tweak-tool from gnome 3 ( gnome-
shell).
   * What exactly did you do (or not do) that was effective (or
     ineffective)?
I try to start the progam from icon in the desktop and from terminal and
neither of both work.
   * What was the outcome of this action?
I've opened a console typing "gnome-tweak-tool" and no start.
>From Gnome-shell, clic on icon and nothing occurrs
   * What outcome did you expect instead?
Open the program.

The terminal shows:
miguel at linuxMiguel:~$ gnome-tweak-tool
Traceback (most recent call last):
  File "/usr/bin/gnome-tweak-tool", line 20, in <module>
    import gi
  File "/usr/lib/python2.7/dist-packages/gi/__init__.py", line 23, in <module>
    from ._gi import _API, Repository
ImportError: /usr/lib/python2.7/dist-packages/gi/_gi.so: undefined symbol:
g_callable_info_skip_return



-- System Information:
Debian Release: wheezy/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 3.0.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=es_ES.utf8, LC_CTYPE=es_ES.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages gnome-tweak-tool depends on:
ii  gir1.2-gconf-2.0           2.32.4-1
ii  gir1.2-gtk-3.0             3.0.12-2
ii  gnome-shell                3.0.2-5 
ii  gsettings-desktop-schemas  3.0.1-1 
ii  python                     2.7.2-9 
ii  python-gobject             2.90.3-2
ii  python2.6                  2.6.7-4 
ii  python2.7                  2.7.2-7 

gnome-tweak-tool recommends no packages.

gnome-tweak-tool suggests no packages.

-- no debconf information