expects people to know their birthdays in the Gregorian calendar. After I had signed in, I scanned down the recent joiners for a Muhammad or Ali or Husayn - or a Miriam or Fatimah. Narry a one did I find, which is odd since it is late-afternoon and evening in the Middle East at the moment. I think that just the year, without the month and day, would suffice, and that would allow room for the yea…