My AT&T phone recently died. I took my sim card out of it and put it into another at&t phone. it's by motorola, but still AT&T. when I turned in on it said, "SIM card is removed or changed. Log in to your MOTOBLUR account to unlock." Then it has a spot for my motoblur ID and password. I don't have an account, but still want to use the phone...how can I get past this?

Thanks.

Make note that I cannot do anything on the phone but turn it on. I received texts but cannot read them because I'm stuck on this screen with the account of the previous owner.