I think you have to remove xmms because it can't be rebuilded, something like emerge -C media-sound/xmms media-plugins/xmms-xmmsmplayer-0.5 (and all other xmms-packages that are in you world file). Afterwords the the revdep-rebuild and --depclean will hopefully work again.
Ehm. What if I want to keep that unsupported package installed until it will rot?
Not my case with xmms, but who knows sometimes I will like to... m. -- [email protected] mailing list

