wonky test on travis TestHDFStore:test_append_with_data_columns
```
======================================================================

FAIL: test_append_with_data_columns (pandas.io.tests.test_pytables.TestHDFStore)

----------------------------------------------------------------------
Traceback (most recent call last):
File "/home/travis/virtualenv/python3.2_with_system_site_packages/lib/python3.2/site-packages/pandas/io/tests/test_pytables.py", line 1330, in test_append_with_data_columns
tm.assert_frame_equal(result, expected)
File "/home/travis/virtualenv/python3.2_with_system_site_packages/lib/python3.2/site-packages/pandas/util/testing.py", line 479, in assert_frame_equal
assert_index_equal(left.index, right.index)
File "/home/travis/virtualenv/python3.2_with_system_site_packages/lib/python3.2/site-packages/pandas/util/testing.py", line 423, in assert_index_equal
right.dtype))
AssertionError: [index] left [datetime64[ns] <class 'pandas.tseries.index.DatetimeIndex'>
[2000-01-24, ..., 2000-01-28]
Length: 5, Freq: B, Timezone: None], right [<class 'pandas.tseries.index.DatetimeIndex'>
[2000-01-24, ..., 2000-01-28]
Length: 3, Freq: None, Timezone: None datetime64[ns]]
```
