You're going to need to use a timeout, or something similar. Since seconds are your smallest unit, make the 'jail time' count in seconds; e.g., 1 hour in jail would be 3600 seconds. Store that somewhere, like a clientr. variable.
Then, format those seconds into the hh:mm:ss format. There are functions in the Code Gallery for that, I think. But it's pretty easy math:
hours = jailTimeinSeconds / 3600
minutes = (jailTimeinSeconds % 3600) / 60
seconds = (jailTimeinSeconds % 3600) % 60
After that, you're going to need to do some special formatting to put zeros in front of single-digit numbers. (As simple as checking if the number < 10.)
Then just display that however you want.