That annoying little tune has, fortunately, disappeared from radios here by now - it's been weeks since I've last heard it...
There's actually a website dedicated to it - but it's only available in German:
You can even listen to the song or watch the video there (once you're past the intro-screen, click on "Hören und Sehen", there's a tracklist at the bottom from which you can either select the "Original Mix" or the "Koroko Italo Mix" - and there's a link on the right side (below the title "Sehen") with which you can watch the video (audio & video are both in RealPlayer format).
Essentially, the whole thing started out as a song for children (as Mrniji has already mentioned), and the writer/composer put the whole thing on the internet so that others could "enjoy" the music as well: the whole thing got so popular that they released a CD
with the song, which - uncomprehensible as it may seem - sold in thousands if not millions...