emerge failed, but when i did a ln /usr/kde/3/bin/artsc-config /bin/artsc-config -s otherwise i think it doesn't fine arts-config or it tries to look for it in /bin/ or whatever. Then it doesn't include the necessary include dirs. That's why there was a comment on an earlier bug not finding an artsc.h file or something. hopefully u guys get this fixed soon, as it seems really trivial to fix :).
I've committed a fix. Please test it.
i tried your patch, and it emerged fine :).