FEniCS out-of-box example fail

[mzh]

Dear Forum
Is anyone using FEniCS to perform finite-element method calculations? I want to work myself into PDE's and I found this Python based software. After installation, I tried to run the example, but I get the following error:
I installed the FEniCS binary on my MacBook Pro running under MacOS X 10.6.3 as described in the installation instructions.
Installation seems successful, at least i can open the fenics terminal.
So I 'cd' into

$ /Applications/FEniCS.app/Contents/Resources/share/dolfin/demo/pde/poisson/python

and hit


$ python demo_poisson.py


This is what I get:


Traceback (most recent call last):
File "demo_poisson.py", line 37, in <module>
from dolfin import *
File "/Applications/FEniCS.app/Contents/Resources/lib/python2.6/site-packages/dolfin/__init__.py", line 13, in <module>
from dolfin.cppimports import *
File "/Applications/FEniCS.app/Contents/Resources/lib/python2.6/site-packages/dolfin/cppimports.py", line 4, in <module>
import dolfin.cpp as cpp
File "/Applications/FEniCS.app/Contents/Resources/lib/python2.6/site-packages/dolfin/cpp.py", line 28, in <module>
_cpp = swig_import_helper()
File "/Applications/FEniCS.app/Contents/Resources/lib/python2.6/site-packages/dolfin/cpp.py", line 24, in swig_import_helper
_mod = imp.load_module('_cpp', fp, pathname, description)
ImportError: dlopen(/Applications/FEniCS.app/Contents/Resources/lib/python2.6/site-packages/dolfin/_cpp.so, 2): no suitable image found. Did find:
/Applications/FEniCS.app/Contents/Resources/lib/python2.6/site-packages/dolfin/_cpp.so: mach-o, but wrong architecture


Any help would be very appreciated. I though before I start screwing up a clean installation, I just ask for help because it might be a minor thing to fix. Unfortuantely, no real help from the FEniCS page yet, that's why I'm here.
Kind regards and thank you for the great work.