I ran into problems when I tried to unlock my T-Mobile US Blackberry Curve 8320. I tried two places and neither could unlock it using traditional methods. They claimed they could not find subsidy (or remote unlock) codes because my phone’s IMIE was not found. As blackberryfaq.com suggests, there are cases when a blackberry cannot be unlocked using remote unlock codes.
The good news is that there are other methods to unlock a phone. http://www.universal-sim.org offers a hardware and firmware solution that worked for me. It involves inserting an additional card into the SIM compartment and cutting away some plastic from your carrier’s SIM card to make more room.
If you want to do this yourself you will also need a ISO card reader and must be willing to run programming software for it. After the whole process is done, when you check if the phone is unlocked it shows that the subsidy lock is ACTIVE but my 8320 still works perfectly on the Rogers Wireless network.