Build gcc for powerpc 405

I'm trying to compile gcc for powerpc 405.
mpfr and gmp were successfully configured and installed.
The output libraries are located in my_gmp_path, my_mpfr_path
Then successfully ran ./configure for gcc:
./configure --target=powerpc-405-linux --with-gmp=my_gmp_path --with-mpfr=my_mpfr_path --prefix=my_gcc_path

Then I ran make which gave the following error message:
/GNU/gcc/gcc-4.3.2/host-x86_64-unknown-linux-gnu/gcc/cc1: error while loading shared libraries: libmpfr.so.1: cannot open shared object file: No such file or directory
configure: error: cannot compute suffix of object files: cannot compile
See `config.log' for more details.
make[1]: *** [configure-target-libgcc] Error 1
make: *** [all] Error 2

I tried to update LD_LIBRARY_PATH by adding 2 lines to ld.so.conf:
my_gmp_path/lib
my_mpfr_path/lib

But I still got the above error message.
Can you help ?

Thanks.

1) 'gcc' alone won't do. Things compiled with this new
tool will depend on libs etc. not present in the target
system.
And gcc must be build in a build directory just outside
gcc-4.3.2/
A --prefix different from /usr/local/ is necessary,
files will conflict with your system, if the tools are
in a known path. ( libc6 )
/home/zvivered/crosstools/ or /usr/local/tools/ will do.

2) A tool chain will usually be 'binutils' 'gcc'
'newlib' (or glibc) 'insight' (or gdb)

3) Build tools for making tool chains are here
http://www.kegel.com/crosstool/
http://www.kegel.com/crosstool/crosstool-0.43/
....

I second the recommendation for crosstool. I've successfully used it to create cross compilers for ARM hosts, and it was fairly simple. Slow, but straightforward if you follow the recipe.
--- rod.