just an FYI, if you already dont know, you cant utilize the UMA function on a unlocked bb (non provider phone). Another words, my T-Mobile unlocked 8900 will not work on Rogers UMA service, everything else works -> wifi browsing, calling, mms, sms, etc.
As dmattox mentioned, in wifi diagnostics, it shows the phone is trying to connect to tmo network even though i am on rogers. I have looked everywhere on the phone and net and have come to this conclusion... no UMA for me