Android API 16 NDK cwctype and string build errors

Question

Android NDK newbie question.

I'm trying to compile a library using the Android NDK. I'm building for API16 and get the following errors in the build:

In file included from /Volumes/MacAirExt/Android/android-ndk-r10e/sources/cxx-stl/llvm-libc++/libcxx/include/cwchar:107: /Volumes/MacAirExt/Android/android-ndk-r10e/sources/cxx-stl/llvm-libc++/libcxx/include/cwctype:88:9: error: no member named 'iswblank' in the global namespace; did you mean 'isblank'? using ::iswblank;

AND

In file included from /Volumes/MacAirExt/Android/android-ndk-r10e/sources/cxx-stl/llvm-libc++/libcxx/include/string:438: /Volumes/MacAirExt/Android/android-ndk-r10e/sources/cxx-stl/llvm-libc++/libcxx/include/cwchar:132:9: error: no member named 'vfwscanf' in the global namespace using ::vfwscanf;

etc

If I build for API21, I don't get any build errors. I guess the library (LibMailCore) is utilising string functions only available in the latest Android API.

Any experts out there know how to get around this?

Thanks.