If you don’t want to waste 1 hour debugging…
Monday, June 16th, 2008… call gtk.gdk.threads_init() when you want to work with threads in a PyGTK application.
Well, to not leave this post so short, I’ll also refer a post explaning threads on PyGTK which looks quite good (I didn’t look carefuly at it because I already knew 99% of what it says… it’s a pity that because of that I didn’t notice the 1% that I didn’t know and which would have saved me one hour of debugging :/). Also, note that if you write your own __init__ function in order to pass data to the thread you will have to call threading.Thread.__init__(self) somewhere in it.