I suspect that Anja is referring to the 1957 Russian animated adaptation of the story, which I also loved as a small child. (There was an American animated adaptation in 1995 that was supposedly really awful, too.) The Russian film has recently been re-released on DVD (albeit with a different dub), so it shouldn't be that hard to obtain.
A friend and I are just starting to download this promising series; I wonder if it would be too much to ask if any of you fine fans might help reseed episode 6 and the HQ episode 7?