Soon, the old version of games-kids/childsplay will go away and that's the only ppc keyworded version. I'd prefer to have the ppc keyword explicitly dropped on the old version or the ppc keyworded added for childsplay-0.90.1.ebuild so ppc presence in that package doesn't just suddenly disappear with the removal of the old version.
When I ran 0.90.1, the display did not work properly when the game went to full screen (leaving me with a frozen X session and that annoying music playing in the background). I am not sure what the cause of that would be. Portage 2.1.3.16 (default-linux/ppc/ppc32/2007.0/G4, gcc-4.1.2, glibc-2.6.1-r0, 2.6.21-gentoo-r3 ppc) ================================================================= System uname: 2.6.21-gentoo-r3 ppc 7447A, altivec supported Timestamp of tree: Tue, 06 Nov 2007 03:30:01 +0000 ccache version 2.4 [enabled] app-shells/bash: 3.2_p17 dev-java/java-config: 1.3.7, 2.0.33-r1 dev-lang/python: 2.4.4-r5 dev-python/pycrypto: 2.0.1-r6 dev-util/ccache: 2.4-r7 sys-apps/baselayout: 2.0.0_rc5 sys-apps/sandbox: 1.2.18.1-r2 sys-devel/autoconf: 2.13, 2.61-r1 sys-devel/automake: 1.4_p6, 1.5, 1.6.3, 1.7.9-r1, 1.8.5-r3, 1.9.6-r2, 1.10 sys-devel/binutils: 2.18-r1 sys-devel/gcc-config: 1.3.16 sys-devel/libtool: 1.5.24 virtual/os-headers: 2.6.21 ACCEPT_KEYWORDS="ppc" CBUILD="powerpc-unknown-linux-gnu" CFLAGS="-O2 -mcpu=G4 -mtune=G4 -maltivec -mabi=altivec -pipe" CHOST="powerpc-unknown-linux-gnu" CONFIG_PROTECT="/etc /usr/share/X11/xkb" CONFIG_PROTECT_MASK="/etc/env.d /etc/env.d/java/ /etc/gconf /etc/gentoo-release /etc/revdep-rebuild /etc/terminfo /etc/texmf/web2c /etc/udev/rules.d" CXXFLAGS="-O2 -mcpu=G4 -mtune=G4 -maltivec -mabi=altivec -pipe" DISTDIR="/usr/portage/distfiles" FEATURES="ccache distlocks metadata-transfer sandbox sfperms strict unmerge-orphans userfetch" GENTOO_MIRRORS="http://gentoo.osuosl.org/ " LDFLAGS="-Wl,--as-needed" LINGUAS="en_US" MAKEOPTS="-j2" PKGDIR="/usr/portage/packages" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --compress --force --whole-file --delete --delete-after --stats --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages --filter=H_**/files/digest-*" PORTAGE_TMPDIR="/var/tmp" PORTDIR="/usr/portage" PORTDIR_OVERLAY="/usr/portage/local/layman/sunrise /usr/portage/local/layman/gnustep /usr/portage/local/layman/enlightenment" SYNC="rsync://rsync.gentoo.org/gentoo-portage" USE="X aac acl alsa altivec berkdb bitmap-fonts branding cdr cli cracklib crypt cups curl dbus dri dvd flac fortran gdbm gif gpm gtk hal iconv ipv6 isdnlog jpeg midi mozbranding mudflap ncurses nls nptl nptlonly ogg opengl openmp pcre perl png ppc pppd python readline reflection session spell spl ssl tcpd theora tiff truetype-fonts type1-fonts unicode vorbis xorg zlib" ALSA_CARDS="aoa aoa-fabric-layout aoa-onyx aoa-soundbus aoa-soundbus-i2s aoa-tas aoa-toonie powermac usb-audio via82xx" ALSA_PCM_PLUGINS="adpcm alaw asym copy dmix dshare dsnoop empty extplug file hooks iec958 ioplug ladspa lfloat linear meter mulaw multi null plug rate route share shm softvol" ELIBC="glibc" INPUT_DEVICES="keyboard mouse evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LINGUAS="en_US" USERLAND="GNU" VIDEO_CARDS="radeon" Unset: CPPFLAGS, CTARGET, EMERGE_DEFAULT_OPTS, INSTALL_MASK, LANG, LC_ALL, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS
dropped the keyword. Feel free to re-keyword a later version if it works on ppc.