I'm using the Boost.DateTime IO system to create customized date/time strings. While the library supports quite a lot of format flags out of the box I'm missing a format flag to print a single-digit hour. There is the format flag %k though (see http://www.boost.org/doc/html/date_time/date_time_io.html#date_time.format_f...) - however it adds a preceding blank for single-digit hours. I guess there is currently no format flag for single-digit hours? Is it possible then to extend the Boost.DateTime IO system somehow to add your own format flag? While I could use another library like Boost.Format additionally I prefer to stick to one (it might make more sense then to switch to Boost.Format completely)? Boris