time_format in field type "text_time"

In your Wiki i found this in the example of field "text_time": // 'time_format' => 'h:i:s A',

But when I change the format to 24h like this "H:i" or "G:i" it will not affect anything.
The time_format is always the same..

I hope this feature will be fixed soon, or you can tell me what I'm doing wrong now.