I bought my iphone off ebay a few months ago. It's a 2G version (i think thats what you call it) and it was unlocked. Are all unlocked iphones jail broken? I never really understood how all that works exactly to tell you the truth. All that I know is I can throw my T-mobile sim card in it and it works. As it did, but today I upgraded to 3.0 and in itunes I get this message "the sim card inserted in this iphone does not appear to be supported". I can't do anything with it now. Well damn. Is there anyway to go back to my older version and unlock it again?

Thanks for any help.
Thanks for any help.