PyGTK Notebook button_press_event connection

[Luigi]

Hi all!

I have an application that uses a gtk.Notebook to show the content of a
GUI. Each page of it has a gtk.Label with a text that explains the
content. Each page is added to the notebook with the method
append_page(child, tab_label=None), passing a gtk.Label instance as
tab_label variable.

Now I'd like to connect to the button_press_event of the gtk.Label a
function call. I've done something like this:

<code>

notebook = gtk.Notebook()
...
child = gtk.Frame()
...
label = gtk.Label('Any text')
label.connect('button_press_event', a_function)
...
notebook.append_page(child, label)

</code>

But the button_press_event event is not intercepted (nothing happens
when I click on the tab label).

Any idea to solve this question?

Thanks

Luigi