This hint allows you to change your current displayed time format of the menubar clock to anything you like, i.e. instead of "1:40" you can have "13.02. 13:40" or "13 Feb 13:40". Compared to the modification mentioned above, this really allows full customization of the displayed time/date.
Read the rest of the article for the how-to...
Instructions
- Start Terminal.app
- cd ~/Library/Preferences (i.e. navigate to your private Preferences directory).
- Open the file .GlobalPreferences.plist To do this, you can just enter open .GlobalPreferences.plist at the prompt. If you have the Developer Tools installed, this will open the file in PropertyListEditor.app. I am not sure what happens if you don't have the DeveloperTools, but I would assume the file is opened in TextEdit.app. You can also use Marcel Bresink's PrefEdit to edit the file.
- Locate the key with the label NSTimeFormatString. If you have opened the file in TextEdit.app, this will look something like
NSTimeFormatString
if your current clock format is "13:40"
%H:%M
- Edit the format string any way you like. To get the "13.02. 13:40" format, the format string should be "%d.%m. %H:%M" (without the quotes). For a complete list of format string possibilities, see Dates to Strings in Apple's Developer Documentation.
- Kill the SystemUIServer process to see the updated time/date format in the menubar (or logout/login). For this, you must have the Menu Bar Clock enabled in System Preferences -> Date & Time -> Menu Bar Clock.
NOTE: I do not know what consequences this hack has other than changing the menu bar time format. Since NSTimeFormatString is a global option, it is possible that some other apps use this in a way which is incompatible with a format containing dates and other stuff. Use at you own risk! I have this running a few days now without any problems.

