The jury said the film depicts ''the confusion of the modern world in an animated form.''   Wada, 31, who now lives in London, said, ''I am proud to win this award. I feel relieved because I used to think my works were rather hard to understand.''   ''In the work, the rabbit (admired by people) doesn't have any particular significance at all but I depicted it because I liked it,'' he said.   The festival's top prize -- the Golden Bear for best film -- went to ''Caesar Must Die'' directed by brothers Paolo and Vittorio Taviani.   Meanwhile, a festival jury comprised of children gave a special award for a film for viewers aged 13 or younger to the Japanese work ''Kikoeteru, furi wo sita dake (I only pretended to hear you).''   Kaori Imaizumi, a 30-year-old nurse in Tokyo, used her time taking maternity leave to shoot the film depicting the life of a girl after losing her mother. ''I cannot even believe my film was shown'' in the Berlin festival, Imaizumi said.   The short Japanese animation titled ''663114'' by Isamu Hirabayashi, on the theme of last March's devastating quake and tsunami and subsequent nuclear crisis, also received an award in a similar competition for films for youths aged 14 to 17.