PyTables: invalid combinate of [values_axes] on appending data
I got the following error when appending data to an HDF5 file:

>  File "/opt/epd/7.3-2_pandas0.11/lib/python2.7/site-packages/pandas/io/pytables.py", line 610, in append
>     self._write_to_group(key, value, table=True, append=True, *_kwargs)
>   File "/opt/epd/7.3-2_pandas0.11/lib/python2.7/site-packages/pandas/io/pytables.py", line 871, in _write_to_group
>     s.write(obj = value, append=append, complib=complib, *_kwargs)
>   File "/opt/epd/7.3-2_pandas0.11/lib/python2.7/site-packages/pandas/io/pytables.py", line 2998, in write
>     return super(AppendableMultiFrameTable, self).write(obj=obj.reset_index(), data_columns=data_columns, *_kwargs)
>   File "/opt/epd/7.3-2_pandas0.11/lib/python2.7/site-packages/pandas/io/pytables.py", line 2740, in write
>     min_itemsize=min_itemsize, *_kwargs)
>   File "/opt/epd/7.3-2_pandas0.11/lib/python2.7/site-packages/pandas/io/pytables.py", line 2484, in create_axes
>     self.validate(existing_table)
>   File "/opt/epd/7.3-2_pandas0.11/lib/python2.7/site-packages/pandas/io/pytables.py", line 2098, in validate
>     raise ValueError("invalid combinate of [%s] on appending data [%s] vs current table [%s]" % (c,sax,oax))
> ValueError: invalid combinate of [values_axes] on appending data [name->values_block_0,cname->values_block_0,axis->None,pos->1,kind->integer] vs current table [name->values_block_0,cname->values_block_0,axis->None,pos->1,kind->float]

The file only contains one DataFrame and I verified that, if I read data from the file, the file DataFrame and the DataFrame I am trying to append have the same column order and the same dtypes for those columns. In addition, index columns have the same types <class 'pandas.tseries.index.DatetimeIndex'>, <class 'pandas.core.index.Int64Index'>. Why am I still getting this error?
