Its origin is from kde-look, so no not only a ubuntu widget but ubuntu
obviusly accepted it.. but as of other distros or so i have no knowledge..
but the source is here:
http://www.kde-look.org/content/show.php/Domino?content=42804
Hmm, it looks like you might be better off asking the dev to port the
theme to KDE 4. Apparently someone tried but did not get very far,
it's in the comments. Naturally, KDE cannot just make it work without
it being ported.
as stated in the comments the org. developer isent involved so im
pushing for it werever i can, cause it is a big obstacle for me to go
to kde4, mabe the one obstacle as desgin and looks is the formost
reason to staing whit kde3 as i dont want to be forced change the looks
of my desktop ever..:/