no device event controller found

["Tomas KRAMAR" <kramar tomas gmail com>]

Hello,

I am developing an application using a gstreamer backend and pygtk.

I create the gstreamer bus and connect a message signal:
bus.connect('message', self.on_message)

However, several people reported, that self.on_message is never
called, and they see following warnings in the output:

atk-bridge-WARNING **: failure: no device event controller found.

I thought this is something related to gstreamer and already asked on
their mailing list, but they told me the warning has nothing to the
with gstreamer, but rather with atk.

I'd like to know what is causing this error, and what is the way to
fix it. Is there some package missing?

Thank you

Regards
Tomas