Comment 4 for bug 974411

got this via mail from Ask:

I think I understand why this is failing now, and have decided
to remove the auto_delete support from virtual transports,
as I believe that it is prone to race conditions. The only
way this could be implemented properly is if it is able
to know how many actual consumers there are of the queue
before it can delete it.

I will be releasing a new kombu bugfix release shortly.