reindex kills IPython
I'm running pandas 0.7.2 and IPython 0.12, the following toy example reproduces the behavior on my machine 100% of the time. 

``` python
df = pandas.DataFrame({'A' : ['foo', 'bar', 'foo', 'bar',
                      'foo', 'bar', 'foo', 'foo'],
                  'B' : ['one', 'one', 'two', 'three',
                        'two', 'two', 'one', 'three'],
                   'C' : randn(8), 'D' : randn(8)})
df
grp = df.groupby('A')
tstgrp = grp.get_group('foo')
```

....
Now typing 
    tstgrp.reindex( 

crashes the IPython kernel. I am actually guessing this is an IPython bug, but I know that Pandas does hook in to IPython so I figured I'd start here.
