I googled this same problem and was linked to this site, so here I am new register!
I'm receiving the same indication as others EXCEPT.. My iPad is not jail broken, only my iPhone is. I started getting this indication on my iPad just recently and I haven't sync any of my iOS devices in about two months. I'm wondering if the app picked up my jail broken device on my iPhone and is now not letting me on through my non jail broken iPad as well
My gf signs on under my user name on her own non jb iPad and she gets on fine. She has not upgraded to the latest optimum version.
I don't understand why I'm getting this "unauthorized" indication if my iPad is not jail broken. I'm currently running 4.3.3. I should note that my iPad was once jail broken on versions 4.0-4.1 but that was ages ago.