It depends on which phone you're trying to unlock. Since it's in the RIM side, I'm guessing it's a Blackberry and since all the new Blackberrys have
GSM or
GSM &
CDMA capabilities, it should be pretty straight forward.
All you have to do is purchase an unlock code and then follow the simple how-to instructions. More details would make it easier to find the appropriate unlock option.
Let us know and we'll help you figure it out. Feel free to send me an e-mail or a PM if you'd like.