cot: std::string doesn't work?

Gives linker errors:
external/stlport/stlport/stl/_alloc.h:161: error: undefined reference to 'std::__node_alloc::_M_deallocate(void*, unsigned int)'
external/stlport/stlport/stl/_alloc.h:158: error: undefined reference to 'std::__node_alloc::_M_allocate(unsigned int&)'
external/stlport/stlport/stl/_string.c:600: error: undefined reference to 'std::__stl_throw_length_error(char const*)'