Mp3 question

Quick question for the technically enlightened.

Im wondering if it is at all possible to alter an mp3 file such that you can place something that signals a loop and if so, what type of program I would need. An ideal example of what I would be looking for would be for instance you have an mp3 file that is 5:42 in length and when it reaches say 4:57, it loops back to 1:35 and continues playing. (Mind you this is just an example I made up on the fly.)

If this is not an option, could anyone point me in the right direction or something similar? I have great faith in you all!

Jam it back in, in the dark.