Update GCC version to use wchar_t.

I’m working on a Q2687 v7.46. My toolchain is using GCC 4.0.1.
I would like to use in my application : wchar_t type, L"String whith french char like é è à …", wstream, swsprintf, …
It seems this is impossible with GCC 4.0.1 and the actual C++ librairie.
I have tried to compile with toolchains from CodeSourcery which have the 4.7.2 version of GCC. It solves all my compilation problems with wchar_t. But I have link problems with the ARM_GNU version, and EABI mismatch version with the ARM_EABI version.

Is it possible to make a toolchain with GCC 4.7.2 ?
How can I do it ?
Or should I avoid the wchar_t type ?
Thank you.

We already made some tests with the latest distribution from CodeSourcery, and it appeared that… it is indeed not working correctly “out of the box” with the Open AT environment…
We’re planning to push a little bit more the study (probably something to tune in the linker script).
We’ll keep you updated if we find a solution.