Returning null connection

[the.question]

I had to call T-mobile for some technical help this morning. They had me, among other things, wipe my Blackberry. Now when trying to use JiveTalk or WeatherBug, I get a message saying "Malformed Address. Returning null connection". Does anyone know what would be causing this and how to fix it?

Also, the reason that I had called T-mobile in the first place is due to the fact that my Curve keeps dropping my Wi-Fi connection. I was told by the T-mobile rep that this was a known issue with the Curve and that the next release of software will solve the problem. Does anyone else have this problem? It is mostly when I make and receive phone calls. Initially, everything is fine, but after about two minutes the call gets dropped and the phone says "Call Failed". T-mobile is sending out a new Curve, which is my third now, and told me that if the next one does not work, I may have to switch to another Wi-Fi phone.