How to convert Sprint koz music files to mp3?

Wel my mother just got an iPhone 4s and she wants to transfer the music from her old phone to her iPhone. After struggling to figure out how to get my computer to read the card reader that I put my mom's sim in, now the sim card has come up and I can see all the data files. Now I've run into another problem. Most of the music files, downloaded from the Sprint store (legally purchased) are in folders.koz. I've never even heard of that before. A couple of the songs that were downloaded elsewhere… Are in normal mp3 format. How can I convert koz to mp3? I've googled plenty of times, with no luck. No ehow.com links please, it didn't work. My mom spent $300+ on these songs and definitely doesn't want to have to repurchase them…

Goto filestube.com and search for the AVS Audio converter, there you'll get the link for the downloads, if you're a torrent user seek that on thepiratebay.se or kat.ph and get that software, import your KOZ file and convert your preferred mp3 format. AVS supports KOZ extension whereas most converter don't.