A portable, std::string-like string class which is not std::string

For various (C++11 std::string-change-related) reasons I would like to use a non-std::string string class in some places in my C++11-ish code, which need to be agreeable with several versions of several C++ compilers.

Now, I don't really mind whether my strings behave in pre-C++11-style or post-C++11 way; and I don't care about performance either. I just want a nice reliable string class which under no circumstances gives me errors involving std::__cxx11::string and other such voodoo.

What are my options? Can I/should I replicate some single compiler's implementation in my own header files? Is GCC's vstring an option? Something else?