Please Indicate One: * [ ] Editorial * [X] Question * [ ] Feedback * [ ] Blocking Issue * [ ] Non-Blocking Issue Please Describe the Issue: for ABNF in Date and Time : as2-partial-time = time-hour ":" time-minute [":" time-second] [time-secfrac] shouldn't it be as2-partial-time = time-hour ":" time-minute [":" time-second [time-secfrac] ] since time-secfrac has few interest if time-second is not provided.