When it comes to cell phones, the words "jailbreak" and "unlock" are often used interchangeably. However, you don't jailbreak your BlackBerry in the same sense that iPhone users jailbreak their devices. Unlike Apple, BlackBerry allows the use of third-party applications on its devices. iPhone users jailbreak their phones so they can have access to the type of applications that Blackberry users already have access to. Jailbreaking your BlackBerry lets you use it on any GSM network, even if your carrier doesn't make BlackBerrys available for use on its network.
Navigate to "SIM Card" under "Advanced Options." Click the menu button to pull up the menu. Scroll down to and click on "Options" or "Settings," then go to "Advanced Options." Highlight and click "SIM Card."
Type "MEPD" using your phone's keypad. Note that you will not see text appear on the screen while you are typing. You should see the words "Network as Active" displayed on your screen.
Hold "Alt" while typing in your MEP code. You can get this code by calling your carrier and asking for it. Alternatively, pay an unlocking service to provide you with the code.
After entering the code, you should see "Network Disabled" on your screen. This means you have successfully unlocked your Blackberry.