Test failures on FreeBSD 9.1
```
% uname -a
FreeBSD XXXX.saltant.net 9.1-STABLE FreeBSD 9.1-STABLE #0 r248078: Fri Mar  8 20:36:00 EST 2013     root@XXXX.saltant.net:/usr/obj/usr/src/sys/NIPPL  amd64
% pkg_info -xE pandas
py27-pandas-0.11.0.r1
% pkg_info -xE ^python
python27-2.7.3_6
% pkg_info -xE numpy
py27-numpy-1.6.2_1,1
% nosetests pandas.tests.test_index:TestMultiIndex.test_legacy_pickle
E
======================================================================
ERROR: test_legacy_pickle (pandas.tests.test_index.TestMultiIndex)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/site-packages/pandas-0.11.0rc1-py2.7-freebsd-9.1-STABLE-amd64.egg/pandas/tests/test_index.py", line 1060, in test_legacy_pickle
    obj = pickle.load(open(ppath, 'r'))
  File "/usr/local/lib/python2.7/pickle.py", line 1378, in load
    return Unpickler(file).load()
  File "/usr/local/lib/python2.7/pickle.py", line 858, in load
    dispatch[key](self)
  File "/usr/local/lib/python2.7/pickle.py", line 1090, in load_global
    klass = self.find_class(module, name)
  File "/usr/local/lib/python2.7/pickle.py", line 1124, in find_class
    __import__(module)
ImportError: No module named multiarray

----------------------------------------------------------------------
Ran 1 test in 0.002s

FAILED (errors=1)
```
