Wow, I just checked the current changelog and Pat has gone all bleeding edge...
What's up with these posts about "current not up to date"? "Stable" most certainly is... Glibc-2.5, gcc-4.1.2, binutils-2.17.x, coreutils-6.7, Xorg-7.2... That's more bleeding edge than I like to do myself...
Holy crap. Never thought I'd see the day when Slackware would do that.
So, yea... That's probably your issue. Current coreutils-6.7 was built against glibc-2.5 but fakeroot probably isn't being maintained all that well (It's a debian thing, what do you expect?)
Why don't you download the current source directory of coreutils from slackware current and pass
to the build script? That should fix your problem... Assuming your hitting a perms problem as the DIY mailing list suggests. Just make sure you build the package with the build number ONE HIGHER than what is installed and do an "upgradepkg"... I'm sure I don't need to tell you not to do a "removepkg" on coreutils...