Asks for pin # when I try to make a call on my new Blackberry Torch 9800

Hi all!
I just bought a new Blackberry torch 9800 (unlocked)
My previous phone was the same exact phone (I loved my old phone so much that I wanted a new one since the screen and roller button didn't always work).
When I put my old sim card in my new phone and tried to make a call, it asked for me to enter a pin number??
Please help! :(

Hi, how do you confirm that this device indeed unlocked? Goto Options-Device-Advanced System Settings-SIM Card-Type MEPD, If it says DISABLED next to Network, then it is unlocked.