Cross compiler i686-->PowerPC/vxWorks

Good evening,
I'm trying to configure gcc 3.4.5 to be cross compiler with i686 as
host and powerpc-wxworks (with altivec support) as target.
I'm working under msys and I'm using the mingws's compiler (gcc
3.4.2).
I have lunched configure command as:

../configure --with-gcc --with-gnu-ld --with-gnu-as --with-gnu-ar
--enable-threads  --target=powerpc-vxworks --enable-language=c,c++
--enable-altivec  --disable-install-libiberty --without-headers

The configure command generates a Makefile, and the report is the
follow:

creating cache ./config.cache
checking host system type... i686-pc-mingw32
checking target system type... powerpc-wrs-vxworks
checking build system type... i686-pc-mingw32
checking for a BSD compatible install... /bin/install -c
*** This configuration is not supported in the following
subdirectories:
     target-libiberty
    (Any other directories should still work fine.)
checking for i686-pc-mingw32-ar... no
checking for ar... ar
checking for i686-pc-mingw32-as... no
checking for as... as
checking for i686-pc-mingw32-dlltool... no
checking for dlltool... dlltool
checking for i686-pc-mingw32-ld...
C:/msys/1.0/mingw/bin/../lib/gcc/mingw32/3.4.2/../../../../mingw32/bin/ld.exe
checking for i686-pc-mingw32-nm... no
checking for nm... nm
checking for i686-pc-mingw32-ranlib... no
checking for ranlib... ranlib
checking for i686-pc-mingw32-windres... no
checking for windres... windres
checking for i686-pc-mingw32-objcopy... no
checking for objcopy... objcopy
checking for i686-pc-mingw32-objdump... no
checking for objdump... objdump
checking for ppc-vxworks-ar... no
checking for ppc-vxworks-as... no
checking for ppc-vxworks-dlltool... no
checking for ppc-vxworks-ld... no
checking for ppc-vxworks-nm... no
checking for ppc-vxworks-ranlib... no
checking for ppc-vxworks-windres... no
checking whether to enable maintainer-specific portions of Makefiles...
no
updating cache ./config.cache
creating ./config.status
creating Makefile

When I lunch "make" command, there are a great number of warning
as:

../../../gcc/fixinc/fixincl.x:77: warning: string length `552' is
greater than the length `509' ISO C89 compilers are required to support
../../../gcc/fixinc/fixincl.x:122: warning: string length `532' is
greater than the length `509' ISO C89 compilers are required to support
../../../gcc/fixinc/fixincl.x:166: warning: string length `808' is
greater than the length `509' ISO C89 compilers are required to support
../../../gcc/fixinc/fixincl.x:252: warning: string length `5139' is
greater than the length `509' ISO C89 compilers are required to support
../../../gcc/fixinc/fixincl.x:2198: warning: string length `729' is
greater than the length `509' ISO C89 compilers are required to support
../../../gcc/fixinc/fixincl.x:6851: warning: string length `575' is
greater than the length `509' ISO C89 compilers are required to support
../../../gcc/fixinc/fixincl.c: In function `initialize':
../../../gcc/fixinc/fixincl.c:317: error: `SIGQUIT' undeclared (first
use in this function)
../../../gcc/fixinc/fixincl.c:317: error: (Each undeclared identifier
is reported only once
../../../gcc/fixinc/fixincl.c:317: error: for each function it appears
in.)
../../../gcc/fixinc/fixincl.c:326: error: `SIGALRM' undeclared (first
use in this function)

and the follow mistake occurs:

../../../gcc/fixinc/fixincl.c: In function `internal_fix':
../../../gcc/fixinc/fixincl.c:812: warning: implicit declaration of
function `pipe'
../../../gcc/fixinc/fixincl.c:820: warning: implicit declaration of
function `fork'
../../../gcc/fixinc/fixincl.c:849: warning: implicit declaration of
function `sleep'
../../../gcc/fixinc/fixincl.c:864: warning: implicit declaration of
function `fcntl'
../../../gcc/fixinc/fixincl.c:864: error: `F_DUPFD' undeclared (first
use in this function)
../../../gcc/fixinc/fixincl.c: In function `process':
../../../gcc/fixinc/fixincl.c:1394: warning: implicit declaration of
function `wait'
make[2]: *** [fixincl.o] Error 1
make[2]: Leaving directory `/GCC_3.4.5_Sorgenti/gcc/gcc/fixinc'
make[1]: *** [fixinc.sh] Error 2
make[1]: Leaving directory `/GCC_3.4.5_Sorgenti/gcc/gcc'
make: *** [all-gcc] Error 2


It sounds as the vxWorks configuration isn't correct!
Have you any idea or suggests?

Thanks
Massimo