I had this when i got a tour 9630 to use in the uk, when i put my sim card in "My number" was some odd no ive never seen, i found on another forum to dail ##000000 then send, it takes you to th CDMA service edit screen, i cahnged the mobile directory number to my uk number and the IMSIS to my uk number and now it shows me the correct phone o, Im not too sure what consequences this may have an a us network but works fine for me !!!! may be worth writing down what the orig nos were and if you have a prob just re input them ??
below is the post given by the original person and a link to that post (USER NAME JRSCCivic98) Credit where Credit is due !!
wrong phone number on " my number" - BlackBerry Forums at CrackBerry.com
"Dial ##000000 Send and then edit the number at the top with your own. This however doesn't really matter as it's just the CDMA programming on the phone.... something not being used since you're with a GSM provider (T-Mobile). You can Zero out the number of put your own number in and then hit Menu/Save and it'll reboot. Once it's back up it'll have your number in there. Also, as of OS5, you can turn off the My Number option under Phone/Menu/Options and not have it display on the Phone screen. That way you won't see it no matter what number it is set to."