Problem with Freetype

[zappa]

Hello,I'm having trouble with freetype's emerge.
I'm using gentooPPC.
When I emerge --update world,stoped at freetype's config.
I think message told me file is not found,
but unix-def.mk & config.mk are presence under
/var/tmp/portage/freetype-2.1.2/work/freetype-2.1.2/

I'm beginner of Gentoo,If This is my silly mistake,SORRY.

I paste end of error message,thanks!!

FreeType build system -- automatic system detection

The following settings are used:

platform unix
compiler cc
configuration directory ./builds/unix
configuration rules ./builds/unix/unix.mk

If this does not correspond to your system or settings please remove the file
`config.mk' from this directory then read the INSTALL file for help.

Otherwise, simply type `make' again to build the library.

config.mk:21: /unix-def.mk: No such file or directory
config.mk:22: /unix-cc.mk: No such file or directory
builds/freetype.mk:206: no file name for `include'
make: *** No rule to make target `/unix-cc.mk'. Stop.

!!! ERROR: The ebuild did not complete successfully.
!!! Function src_compile, Line 2, Exitcode 2
!!! (no error message)