I've the same problem, first I tried this code:
>>>from django.contrib.gis.gdal import HAS_GDAL
>>>print HAS_GDAL
and the result was:
True
Also I tried this code:
>>> from django.contrib.gis.utils.layermapping import LayerMapping
and the result was:
Traceback (most recent call last):
File "<console>", line 1, in <module>
File "/usr/lib/python2.5/site-packages/Django-1.0.2_final-py2.5.egg/
django/contrib/gis/utils/layermapping.py", line 119, in <module>
from django.contrib.gis.models import GeometryColumns,
SpatialRefSys
ImportError: cannot import name GeometryColumns
thanks for any help :)