In the arm stage3 for uclibc 2005.0 (not armeb) the following files are badly named.... In the directory.... /usr/lib/gcc/arm-gentoo-linux-uclibc/3.4.4/include/g++-v3/arm-gentoo-linux-uclibc/bits/ there are two files called... os_defines. ctype_base. these two files are missing the [h] at the end and therefore g++ programs fail to compile.
upgrade your toolchain, 3.4.6 works fine for me