import pandas fails on trunk
Just upgraded to trunk, import pandas fails now.

``` python
In [1]: import pandas
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<...>/<ipython-input-1-d6ac987968b6> in <module>()
----> 1 import pandas

<...>/lib/python2.7/site-packages/pandas-0.7.0.dev_063ff4b-py2.7-linux-i686.egg/pandas/__init__.py in <module>()
      8 
      9 try:
---> 10     import pandas._tseries as lib
     11 except Exception, e:  # pragma: no cover
     12     if 'No module named' in str(e):

<...>/inference.pyx in init pandas._tseries (pandas/src/tseries.c:87762)()

AttributeError: 'module' object has no attribute 'float16'

In [2]: 

```
