installation problem on Mac

Hi all,
I am trying to install matplotlib on my Mac OS X 10.6.6. I currently have Python 2.7.2 installed. I tried installing ** The installation appears to run fine, but when I try to import pylab ** I am getting the following error message:

from numpy import *
import pylab

Traceback (most recent call last):
File “”, line 1, in
File “/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/”, line 1, in
from matplotlib.pylab import *
File “/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/”, line 220, in
from matplotlib import mpl # pulls in most modules
File “/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/”, line 1, in
from matplotlib import artist
File “/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/”, line 6, in
from transforms import Bbox, IdentityTransform, TransformedBbox, TransformedPath
File “/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/”, line 34, in
from matplotlib._path import affine_transform
ImportError: dlopen(/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/, 2): no suitable image found. Did find:
/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/ no matching architecture in universal wrapper

I am new to Python and any help would be greatly appreciated.