Finally used the discovered paths from ./configure in scripts/crosstool-NG.sh:
- fix Makefile to really, really not used built-in rules and variables
- have scripts/crosstool-NG.sh generated from scripts/crosstool-NG.sh.in
- create a bin-overide directory ( in ${CT_WORK_DIR}/bin ) that contains shell wrappers to the actual discovered tools

/trunk/scripts/crosstool-NG.sh.in | 27 23 4 0 +++++++++++++++++++++---
/trunk/Makefile.in | 50 48 2 0 +++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 71 insertions(+), 6 deletions(-)

 # MIPS specific config options

 config ARCH_mips

     select ARCH_SUPPORTS_BOTH_ENDIAN

     select ARCH_DEFAULT_BE

     select ARCH_SUPPORT_ARCH

     select ARCH_SUPPORT_ABI

     select ARCH_SUPPORT_TUNE

     help

       The MIPS architecture, as defined by:

         http://www.mips.com/