pydata/pandas — pull request #8043 by TomAugspurger (2014-08-15 22:17:05+00:00)
Title: BUG: stack with datetimes

close https://github.com/pydata/pandas/issues/8039

The only change I made was to select from the MultiIndex itself, rather than the underlying `.values` attribute. The test set passed but I want to look at this a bit more closely to make sure everything is ok.