A visit to Wikipedia actually confirms this story (I was sure it was a joke before): http://en.wikipedia.org/wiki/Typhoon_class_submarine#Descrip...
"Typhoon class submarines feature multiple pressure hulls that simplify internal design while making the vessel much wider than a normal submarine. In the main body of the sub, two Delta class pressure hulls lie parallel with a third, smaller pressure hull above them (which protrudes just below the sail), and two other pressure hulls for torpedoes and steering gear."