T-Mobile has roaming agreements with Cingular to use their towers. You can try turning off your phone for an hour. Or you can take out the battery while the phone is still on and put it back after around 5 minutes. But it just may be your phone. I was also thinking about getting an unlocked T809 or D807, but like you said reception can be an issue.

so, heres the story. i bought an unlocked t809 on ebay to use with cingular. the thing is, which i have read on some reviews, is that the reception is horrible. it drops calls, and gets no service in areas where my old phones got great service. the question is, even though its unlocked, is it searchign for the wrong towers or something. i heard that cingular and tmobile share the same towers, but im not sure of this. so, could it be a posibility that my phone is searching for cingular towers but it cant use them or something....? either that or my phone's reception is crap