My Iphone freezes "Loading sms"

[Jumbexx]

Hi! This is my first try here so please don't get mad if i post this at the wrong place.. Well i have this big problem and i can't figure it out where it came from! When i get a text message and i try to open it (the usual green button) then a window fills the screen where it says " Loading sms " and something with " Risinground "!? Well, now it freezes for about 30 sec and then back to desktop. I can't get to my messages at all exept for once in a while when i restart my iphone. That window pops up quickly and then i get to my messages. I have tried looking it up but no good resaults.. Please can anyone help me?

Thanks
//Andy