Actually, I would like to check if the threads working on the queue are still alive. 

However, it occurs to me now that I would need a facility to distinguish between a timeout and an actual join. Unfortunately, my original patch does not provide this, one would have to implement an additional check and think about the correct way to signal a timeout.

Also, there seem to be other people looking for this feature: http://stackoverflow.com/questions/1564501/add-timeout-argument-to-pythons-queue-join