Building modules, stage 2.
make[2]: scripts/mod/modpost: Command not found
make[2]: *** [__modpost] Error 127
make[1]: *** [modules] Error 2
make: *** [kmod_build] Error 2

!!! ERROR: x11-drivers/ati-drivers-8.36.5-r90 failed.
Call stack:
  ebuild.sh, line 1614:   Called dyn_compile
  ebuild.sh, line 971:   Called qa_call 'src_compile'
  environment, line 4146:   Called src_compile
  ati-drivers-8.36.5-r90.ebuild, line 164:   Called linux-mod_src_compile
  linux-mod.eclass, line 516:   Called die

!!! Unable to make  GCC_VER_MAJ=4 KVER=2.6.20-sabayon KDIR=/usr/src/linux kmod_build.
!!! If you need support, post the topmost build error, and the call stack if relevant.
!!! A complete build log is located at '/var/tmp/portage/x11-drivers/ati-drivers-8.36.5-r90/temp/build.log'.

!!! This ebuild is from an overlay: '/usr/portage/local/layman/sabayon'