Hoverinfo text in stacked bar chart

How do I have to specify text to stacked bars?

df.groupby([df.index.date,"message_type"])["message_type"].count().unstack().iplot(kind='bar', barmode='stack')

Gives me a plot with x-axis time and y-axis frequency with groups of message_types. These message_types are in the first place error codes (numbers).

This is perfect, because I want to have numbers for the grouping symbols.

image

Now I have another dataframe where the numbers are translated into text. I want to display the text on mouse hover accordingly. However, passing a list with that error strings does simply not work.