Unlicensed Mobile Access requires a dedicated server to monitor cellular vs Wifi signal strength. Unless you have an account of that server, you will not be seeing uma/UMA.
Your Browser will continue to work with Wifi, but not BlackBerry data or voice.
Rogers now supports UMA on the 8320, but I (like others) have an unlocked t-mobile branded phone. Has anybody figured out a way to change the server addresses in the phone to the ones used by Rogers? Still impossible?
I updated to the latest Rogers OS today, but the phone still shows the t-mobile servers outlined earlier in this thread.