It is well known that we even can not understand mammalian species around us, like dolphin. Does a dolphin with his huge brain speak at some language? Seems to me yes. But why can we not to decode that language with our "supercomputers" :)
Dear Anatoly, you could be interested in the project of the Swedish start up Gavagai AB, which is trying to use an artificial intelligence language analysis software to decrypt dolphin-language.