Q: how to unlock iphone 4 CDMA

My Verizon iPhone 4 is out of contract and i called them to unlock the phone so i can use in another country. Then i got surprised that its actually a CDMA without SIM card so they cannot unlock it. There was nothing they can do from their part and told me to goto itunes.com and download latest software and then install the version for the CDMA career that i intend to use in the other country. Problem is- they were not able to give me exact steps to unlock by going to itunes.com

2nd - i dont know what CDMA career i will use in the other country. I'm looking to get this iphone unlocked so that i can use any career abroad. Can anyone tell me how?