[newbie] tkFileDialog does not show title

[jenswaelkens at gmail.com]

I'm using the tkFileDialog-module in Python 2.7, it works fine except for one thing: when I add a title, the title isn't shown.

e.g. I have this line of code:
inputfilename=tkFileDialog.askopenfilename(defaultextension=".dat", filetypes=(("data file", "*.dat"),("All Files", "*.*") ),title='Select input file')

this works fine i.e. the file selector menu opens but I expected that the text
'Select input file' would be displayed too. Can anyone here explain me how I can achieve this?

kind regards,
Jens