Formatting Numbers

Hey all, does anyone know how to format numbers.I have a cd playing application and the duration is in milliseconds.when i work it all out and i display it its minute:second:milisecond e.g. 5:5:5.how do i format the numbers so that they appear e.g. 05:05:05.i dont want to write if statements to check every time i open a file to see if the resulting minutes and seconds are less than 10!! plus when the seconds are changin it would have to be done too.its just a pain. Call me lazy. Ant ideas are appreciated Thanks.