You don't need to unlock it. You need the MSL number and you can get that by dialing ##000000. You will need to give that number to Cricket or MetroPCS as they generally allow other CDMA devices on their networks. However, I don't believe they offer BlackBerry service.
Good luck trying to get free service.
The difference between stupidity and genius is that genius has its limits.
When you take things for granted, the things you are granted, get taken.
Even a mosquito doesn't get a pat on the back until it starts to work.
Too many people miss the silver lining because they're expecting gold.
[BES 5.0.3 / GroupWise 2012 HP2]