Palm Treo 750

I have a palm treo 750 running Mobile 6 Pro and my carrier is AT&T and I have the plan for mms and text messages but no internet on the phone. I cannot send or download mms messages. I went to the AT&T website and entered my device and did the whole manually edit the network configuration thing. when I would try to send it before, It would send me a text that said it could not send it and say that maybe I didn't have good connection(I did) and to make sure active sync was on (It was). But now that I have gone to the AT&T website and done what it says It will act like Its sending it and then after like 2 minutes I will get that text that I talked about earlier. If someone sends me a text and I try to download it does the same thing. I know no...
(continues)