SDL_TTF underline of wrapped text is not implemented?

apparently, this code is commented out in SDL_ttf.c in the function

SDL_Surface *TTF_RenderUTF8_Blended_Wrapped(TTF_Font *font, const char *text, SDL_Color fg, Uint32 wrapLength)

at line 2082 in

http://hg.libsdl.org/SDL_ttf/file/514e61338063/SDL_ttf.c

does anyone have any ideas how to fix this ? I peeked at the sources but it seems a tad complicated for the non-informed? maybe someone has more experience ?