YouTube member Павел Сутырин says his cat does this regularly.
This happens almost everytime the cat sleeps or just rests. It also answer to sneezing. It's of particular fun when you are ill for real :)
No, I do not pull his tail behind the scenes. =))
It seems to me that the cat is responding in its own way. Maybe something like, “I am listening to you, despite the fact that I’m asleep. Please continue.” Or more likely, “Shut up! I’m trying to sleep!” Then there’s an off chance that he may be doing the feline equivalent of “Bless you.” -via Tastefully Offensive