QGIS » QGIS Application

Since roughly a week, PyQGIS fails to load when starting QGIS and all of the related PyQGIS plugins are disabled. An error message box appears at launch with this text:

[code]
Couldn't load PyQGIS.
Python support will be disabled.

Traceback (most recent call last):
File "", line 1, in
RuntimeError: the PyQt4.QtCore module is version 1 but the qgis.core module requires version -1

Python version:
2.7.2+ (default, Aug 16 2011, 07:56:26)
[GCC 4.6.1]

QGIS version:
1.8.0-Trunk 'Trunk', exported

Python path:
['/usr/share/qgis/python', '/home/webmaster/.qgis/python', '/home/webmaster/.qgis/python/plugins', '/usr/share/qgis/python/plugins', '/usr/lib/python2.7', '/usr/lib/python2.7/plat-linux2', '/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', '/usr/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/dist-packages', '/usr/lib/python2.7/dist-packages', '/usr/lib/python2.7/dist-packages/PIL', '/usr/lib/python2.7/dist-packages/gst-0.10', '/usr/lib/python2.7/dist-packages/gtk-2.0', '/usr/lib/pymodules/python2.7', '/usr/lib/python2.7/dist-packages/ubuntu-sso-client', '/usr/lib/python2.7/dist-packages/ubuntuone-client', '/usr/lib/python2.7/dist-packages/ubuntuone-control-panel', '/usr/lib/python2.7/dist-packages/ubuntuone-storage-protocol', '/usr/lib/python2.7/dist-packages/wx-2.8-gtk2-unicode']
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