exception handling in Tkinter

[msoulier]

In wxPython I install a top-level exception handler to intercept
exceptions and display them in the GUI.

With Tkinter, I'm trying to do the same.

in __init__

 sys.excepthook = self.ExceptionHandler

    def ExceptionHandler(self, type, value, tb):
        tblist = traceback.format_tb(tb)
        for line in tblist:
            text += line
        self.errorDialog(text)

But it's not being called on exceptions. Any ideas?

Thanks,
Mike