qgis - How to set the path to shapely?

I am using QGIS 1.8.0 on Mac OS 10.8.3 with python 2.7. Thanks to other threads in the forum, I have successfully installed shapely here:

/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Shapely-1.2.16-py2.7.egg

However, when I try to use the polygonizer-Plugin in QGIS it tells me that it cannot find shapely.ops. This clearly seems to be a path-problem, but I have no other versions of python installed. I have tried to append the above path to .bash-profile, but to no avail.

Any help is appreciated.

Nils