Bugzilla Bug 118066

Pretty straightforward:
x11-base/xorg-x11 makes libXv a requirement and hence has removed the xv
useflag. This is why this pkg_setup fails:

pkg_setup() {
        if has_version x11-base/xorg-x11 && ! built_with_use x11-base/xorg-x11
xv; then
                die "You need xorg-x11 emerged with xv support to compile
transcode."
        fi
}

For monolithic xorg this is perfectly valid. For modular this doesn't work.
To compile with modular i would change it to:

pkg_setup() {
    if ! has_version >= x11-base/xorg-x11-7.0
          if has_version x11-base/xorg-x11 <has_version x11-base/xorg-x11 && !
built_with_use x11-base/xorg-x11 xv;
                die "You need xorg-x11 emerged with xv support to compile
transcode."
          fi
    fi
}

And yes this *is* ugly and i would rather see the xv useflag being readded to
xorg-x11.

emerge info:
Portage 2.1_pre3-r1 (default-linux/x86/2005.1, gcc-4.0.2, glibc-2.3.6-r2,
2.6.15-rc7-20060101-2 i686)
=================================================================
System uname: 2.6.15-rc7-20060101-2 i686 AMD Athlon(tm) processor
Gentoo Base System version 1.12.0_pre13
dev-lang/python:     2.3.5-r2, 2.4.2
sys-apps/sandbox:    1.2.17
sys-devel/autoconf:  2.13, 2.59-r7
sys-devel/automake:  1.4_p6, 1.5, 1.6.3, 1.7.9-r1, 1.8.5-r3, 1.9.6-r1
sys-devel/binutils:  2.16.1-r1
sys-devel/libtool:   1.5.22
virtual/os-headers:  2.6.11-r3
ACCEPT_KEYWORDS="x86 ~x86"
AUTOCLEAN="yes"
CBUILD="i686-pc-linux-gnu"
CFLAGS="-march=athlon -O2 -pipe"
CHOST="i686-pc-linux-gnu"
CONFIG_PROTECT="/etc /usr/kde/2/share/config /usr/kde/3.5/env
/usr/kde/3.5/share/config /usr/kde/3.5/shutdown /usr/kde/3/share/config
/usr/share/X11/xkb /usr/share/config /var/qmail/control"
CONFIG_PROTECT_MASK="/etc/gconf /etc/terminfo /etc/env.d"
CXXFLAGS="-march=athlon -O2 -pipe"
DISTDIR="/usr/portage/distfiles"
FEATURES="autoconfig candy ccache distlocks sandbox sfperms strict userpriv
usersandbox"
GENTOO_MIRRORS="http://mirror.switch.ch/mirror/gentoo/
http://ftp.romnet.org/gentoo/ http://pandemonium.tiscali.de/pub/gentoo/
http://ftp.uni-erlangen.de/pub/mirrors/gentoo
http://ftp.snt.utwente.nl/pub/os/linux/gentoo http://distfiles.gentoo.org
http://www.ibiblio.org/pub/Linux/distributions/gentoo"
MAKEOPTS="-j2"
PKGDIR="/usr/portage/packages"
PORTAGE_TMPDIR="/var/tmp"
PORTDIR="/usr/portage"
PORTDIR_OVERLAY="/usr/local/portage"
SYNC="rsync://rsync.europe.gentoo.org/gentoo-portage"
USE="x86 ipv6 kdeenablefinal nptl opengl pic unicode zlib elibc_glibc
kernel_linux userland_GNU"
Unset:  ASFLAGS, CTARGET, LANG, LC_ALL, LDFLAGS, LINGUAS

Committed.