The international settings worked for the time displays in applications such as Mail, etc. But the clock on the menu bar still does not show a leading zero.
As I said before, you need to explore. I was able to add it in less than 30 seconds. Let me try to explain. It is easy to do, but more difficult to explain. Go to Sys Prefs/Int'l/Formats pane. Choose Custom in the Times area. Choose Medium in the Show drop down menu. (Medium seems to be the one used by OS X for the menu bar clock.) Here you can arrange the order of the different components as you like. Notice they have little arrows indicating drop down menus. Most of the optional formats offer a leading zero. Even though you have formatted it in the Int'l pane, you must choose for some of your formating to show in the Date & Time/Clock pane. Good Luck.
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leading zero on 24 hour clock
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